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  • 1.
    Aguilar-Calvo, Patricia
    et al.
    Univ Calif San Diego, CA 92093 USA; Pfizer, CA USA.
    Malik, Adela
    Univ Calif San Diego, CA 92093 USA; Fate Therapeut, CA USA.
    Sandoval, Daniel R.
    Univ Calif San Diego, CA USA; GSK plc, PA USA.
    Barback, Christopher
    Univ Calif San Diego, CA USA; Univ Colorado, CO USA.
    Orru, Christina D.
    NIAID, MT USA.
    Standke, Heidi G.
    Case Western Reserve Univ, OH USA.
    Thomas, Olivia R.
    Case Western Reserve Univ, OH USA.
    Dwyer, Chrissa A.
    Univ Calif San Diego, CA USA.
    Pizzo, Donald P.
    Univ Calif San Diego, CA 92093 USA.
    Bapat, Jaidev
    Univ Calif San Diego, CA 92093 USA.
    Soldau, Katrin
    Univ Calif San Diego, CA 92093 USA.
    Ogawa, Ryotaro
    Univ Calif San Diego, CA USA.
    Riley, Mckenzie B.
    Univ Alabama Birmingham, AL USA.
    Nilsson, Peter
    Linköping University, Department of Physics, Chemistry and Biology, Chemistry. Linköping University, Faculty of Science & Engineering.
    Kraus, Allison
    Case Western Reserve Univ, OH USA.
    Caughey, Byron
    NIAID, MT USA.
    Iliff, Jeffrey J.
    VA Puget Sound Hlth Care Syst, WA USA; Univ Washington, WA USA.
    Vera, David R.
    Univ Calif San Diego, CA USA.
    Esko, Jeffrey D.
    Univ Calif San Diego, CA USA.
    Sigurdson, Christina J.
    Univ Calif San Diego, CA 92093 USA; UC San Diego Hlth, CA 92093 USA; Bristol Myers Squibb, CA USA.
    Neuronal Ndst1 depletion accelerates prion protein clearance and slows neurodegeneration in prion infection2023In: PLoS Pathogens, ISSN 1553-7366, E-ISSN 1553-7374, Vol. 19, no 9, article id e1011487Article in journal (Refereed)
    Abstract [en]

    Select prion diseases are characterized by widespread cerebral plaque-like deposits of amyloid fibrils enriched in heparan sulfate (HS), a major extracellular matrix component. HS facilitates fibril formation in vitro, yet how HS impacts fibrillar plaque growth within the brain is unclear. Here we found that prion-bound HS chains are highly sulfated, and that the sulfation is essential for accelerating prion conversion in vitro. Using conditional knockout mice to deplete the HS sulfation enzyme, Ndst1 (N-deacetylase / N-sulfotransferase), from neurons or astrocytes, we then investigated how reducing HS sulfation impacts survival and prion aggregate distribution during a prion infection. Neuronal Ndst1-depleted mice survived longer and showed fewer and smaller parenchymal plaques, shorter fibrils, and increased vascular amyloid, consistent with enhanced aggregate transit toward perivascular drainage channels. The prolonged survival was strain-dependent, only affecting mice infected with extracellular, plaque-forming, but not membrane bound, prions. Live PET imaging revealed rapid clearance of recombinant prion protein monomers into the CSF of mice expressing unsulfated HS, further suggesting that HS sulfate groups hinder transit of extracellular prion protein monomers. Our results directly show how a host cofactor slows the spread of prion protein through the extracellular space and identify an enzyme to target to facilitate aggregate clearance. Prions cause a rapidly progressive neurologic disease and death with no curative treatment available. Prion aggregates accumulate exponentially in the brain of affected individuals triggering neuronal loss and neuroinflammation, yet the molecules that facilitate prion protein aggregation are largely unknown. We have found that prions in the brain preferentially bind to a highly sulfated endogenous polysaccharide, known as heparan sulfate (HS). Here we use genetically modified mice that express poorly sulfated, neuron-derived HS, and infect mice with different prions strains. We find that mice infected with a plaque-forming prion strain show a prolonged survival and fewer plaques compared to controls. We also found that recombinant prion protein was efficiently transported within the interstitial fluid of mice having poorly sulfated HS, suggesting more efficient clearance from the brain. Our study provides insight into how HS retains prion aggregates in the brain to accelerate disease and indicates a specific HS biosynthetic enzyme to target to enhance protein clearance.

  • 2.
    Aguilar-Calvo, Patricia
    et al.
    Univ Calif, CA 92093 USA.
    Sevillano, Alejandro M.
    Univ Calif, CA 92093 USA.
    Bapat, Jaidev
    Univ Calif, CA 92093 USA.
    Soldau, Katrin
    Univ Calif, CA 92093 USA.
    Sandoval, Daniel R.
    Univ Calif, CA USA.
    Altmeppen, Hermann C.
    Univ Med Ctr Hamburg, Germany.
    Linsenmeier, Luise
    Univ Med Ctr Hamburg, Germany.
    Pizzo, Donald P.
    Univ Calif, CA 92093 USA.
    Geschwind, Michael D.
    Univ Calif San Francisco, CA USA.
    Sanchez, Henry
    Univ Calif San Francisco, CA USA.
    Appleby, Brian S.
    Case w Reserve Univ, OH USA.
    Cohen, Mark L.
    Case w Reserve Univ, OH USA.
    Safar, Jiri G.
    Case w Reserve Univ, OH USA.
    Edland, Steven D.
    Univ Calif, CA USA.
    Glatzel, Markus
    Univ Med Ctr Hamburg, Germany.
    Nilsson, Peter
    Linköping University, Department of Physics, Chemistry and Biology, Chemistry. Linköping University, Faculty of Science & Engineering.
    Esko, Jeffrey D.
    Univ Calif, CA USA.
    Sigurdson, Christina J.
    Univ Calif, CA USA.
    Shortening heparan sulfate chains prolongs survival and reduces parenchymal plaques in prion disease caused by mobile, ADAM10-cleaved prions2020In: Acta Neuropathologica, ISSN 0001-6322, E-ISSN 1432-0533, Vol. 139, no 3, p. 527-546Article in journal (Refereed)
    Abstract [en]

    Cofactors are essential for driving recombinant prion protein into pathogenic conformers. Polyanions promote prion aggregation in vitro, yet the cofactors that modulate prion assembly in vivo remain largely unknown. Here we report that the endogenous glycosaminoglycan, heparan sulfate (HS), impacts prion propagation kinetics and deposition sites in the brain. Exostosin-1 haploinsufficient (Ext1(+/-)) mice, which produce short HS chains, show a prolonged survival and a redistribution of plaques from the parenchyma to vessels when infected with fibrillar prions, and a modest delay when infected with subfibrillar prions. Notably, the fibrillar, plaque-forming prions are composed of ADAM10-cleaved prion protein lacking a glycosylphosphatidylinositol anchor, indicating that these prions are mobile and assemble extracellularly. By analyzing the prion-bound HS using liquid chromatography-mass spectrometry (LC-MS), we identified the disaccharide signature of HS differentially bound to fibrillar compared to subfibrillar prions, and found approximately 20-fold more HS bound to the fibrils. Finally, LC-MS of prion-bound HS from human patients with familial and sporadic prion disease also showed distinct HS signatures and higher HS levels associated with fibrillar prions. This study provides the first in vivo evidence of an endogenous cofactor that accelerates prion disease progression and enhances parenchymal deposition of ADAM10-cleaved, mobile prions.

  • 3.
    Alberti, Esteban
    et al.
    Department of Neurobiology, International Center of Neurological Restoration, CIREN, Havana, Cuba..
    Los, Marek Jan
    Interfaculty Institute for Biochemistry, University of Tübingen, Germany; BioApplications Enterprises, Winnipeg, MB, Canada.
    Garcia, Rocio
    Department of Neurobiology, International Center of Neurological Restoration, CIREN, Havana, Cuba..
    Fraga, JL
    Department of Neurobiology, International Center of Neurological Restoration, CIREN, Havana, Cuba..
    Serrano, T.
    Department of Neurobiology, International Center of Neurological Restoration, CIREN, Havana, Cuba..
    Hernandez, E.
    Department of Neurobiology, International Center of Neurological Restoration, CIREN, Havana, Cuba..
    Klonisch, Thomas
    Department of Human Anatomy and Cell Sciences, and Manitoba Institute of Child Health, Winnipeg, Canada.
    Macías, R.
    Department of Neurobiology, International Center of Neurological Restoration, CIREN, Havana, Cuba..
    Martinez, L.
    Department of Neurobiology, International Center of Neurological Restoration, CIREN, Havana, Cuba..
    Castillo, L.
    Department of Neurobiology, International Center of Neurological Restoration, CIREN, Havana, Cuba..
    de la Cuétara, K.
    Department of Neurobiology, International Center of Neurological Restoration, CIREN, Havana, Cuba.
    Prolonged Survival and expression of neural markers by bone marrow-derived stem cells transplanted into brain lesions2009In: Medical Science Monitor, ISSN 1234-1010, E-ISSN 1643-3750, Vol. 15, no 2, p. BR47-BR54Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Bone marrow-derived stem cell transplantation is a potentially viable therapeutic option for the treatment of neurodegenerative disease. MATERIAL/METHODS: We have isolated bone marrow stem cells by standard method. We then evaluated the survival of rats' bone marrow mononuclear cells implanted in rats' brain. The cells were extracted from rats' femurs, and marked for monitoring purposes by adenoviral transduction with Green Fluorescent Protein (GFP). Labeled cells were implanted within the area of rats' striatum lesions that were induced a month earlier employing quinolinic acid-based method. The implants were phenotyped by monitoring CD34; CD38; CD45 and CD90 expression. Bone marrow stromal cells were extracted from rats' femurs and cultivated until monolayer bone marrow stromal cells were obtained. The ability of bone marrow stromal cells to express NGF and GDNF was evaluated by RT-PCR. RESULTS: Implanted cells survived for at least one month after transplantation and dispersed from the area of injection towards corpus callosum and brain cortex. Interestingly, passaged rat bone marrow stromal cells expressed NGF and GDNF mRNA. CONCLUSIONS: The bone marrow cells could be successfully transplanted to the brain either for the purpose of trans-differentiation, or for the expression of desired growth factors.

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  • 4.
    Alexander, Helen K.
    et al.
    Cancer Care Manitoba, Manitoba Institute of Cell Biology, University of Manitoba.
    Booy, Evan P.
    Cancer Care Manitoba, Manitoba Institute of Cell Biology, University of Manitoba; Department of Biochemistry and Medical Genetics, University of Manitoba, Winnipeg, Canada .
    Xiao, Wenyan
    Cancer Care Manitoba, Manitoba Institute of Cell Biology, University of Manitoba.
    Ezzati, Peyman
    Cancer Care Manitoba, Manitoba Institute of Cell Biology, University of Manitoba.
    Baust, Heinrich
    Department of Radiooncology, University of Erlangen, Erlangen, Germany .
    Los, Marek Jan
    Manitoba Institute of Cell Biology, Cancer Care Manitoba; Manitoba Institute of Child Health; Department of Biochemistry and Medical Genetics; Department of Human Anatomy and Cell Science, University Manitoba, Winnipeg, Canada, .
    Selected technologies to control genes and their products for experimental and clinical purposes2007In: Archivum Immunologiae et Therapiae Experimentalis, ISSN 0004-069X, E-ISSN 1661-4917, Vol. 55, no 3, p. 139-149Article in journal (Refereed)
    Abstract [en]

    "On-demand" regulation of gene expression is a powerful tool to elucidate the functions of proteins and biologically-active RNAs. We describe here three different approaches to the regulation of expression or activity of genes or proteins. Promoter-based regulation of gene expression was among the most rapidly developing techniques in the 1980s and 1990s. Here we provide basic information and also some characteristics of the metallothionein-promoter-based system, the tet-off system, Muristerone-A-regulated expression through the ecdysone response element, RheoSwitch (R), coumermycin/novobiocin-regulated gene expression, chemical dimerizer-based promoter activation systems, the "Dual Drug Control" system, "constitutive androstane receptor"-based regulation of gene expression, and RU486/mifepristone-driven regulation of promoter activity. A large part of the review concentrates on the principles and usage of various RNA interference techniques (RNAi: siRNA, shRNA, and miRNA-based methods). Finally, the last part of the review deals with historically the oldest, but still widely used, methods of temperature-dependent regulation of enzymatic activity or protein stability (temperature-sensitive mutants). Due to space limitations we do not describe in detail but just mention the tet-regulated systems and also fusion-protein-based regulation of protein activity, such as estrogen-receptor fusion proteins. The information provided below is aimed to assist researchers in choosing the most appropriate method for the planned development of experimental systems with regulated expression or activity of studied proteins.

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  • 5.
    Aman, Malin
    et al.
    Swedish Sch Sport and Hlth Sci, Sweden.
    Larsen, Karin
    Swedish Sch Sport and Hlth Sci, Sweden; Umea Univ, Sweden.
    Forssblad, Magnus
    Swedish Sch Sport and Hlth Sci, Sweden; Karolinska Inst, Sweden.
    Näsmark, Annica
    Swedish Sch Sport and Hlth Sci, Sweden; Capio Artro Clin, Sweden.
    Waldén, Markus
    Linköping University, Department of Medical and Health Sciences, Division of Community Medicine. Linköping University, Faculty of Medicine and Health Sciences. Swedish Sch Sport and Hlth Sci, Sweden.
    Hägglund, Martin
    Linköping University, Department of Medical and Health Sciences, Division of Physiotherapy. Linköping University, Faculty of Medicine and Health Sciences. Swedish Sch Sport and Hlth Sci, Sweden.
    A Nationwide Follow-up Survey on the Effectiveness of an Implemented Neuromuscular Training Program to Reduce Acute Knee Injuries in Soccer Players2018In: The Orthopaedic Journal of Sports Medicine, ISSN 2325-9671, Vol. 6, no 12, article id 2325967118813841Article in journal (Refereed)
    Abstract [en]

    Background: A cruciate ligament (CL) injury is a severe injury in soccer. Neuromuscular training programs have a well-documented preventive effect, but there are few studies on the effectiveness of such a program at a national level. The Swedish Knee Control Program (KCP) was found to be effective in preventing CL injuries in youth female soccer players. The KCP was implemented nationwide in Sweden in 2010. Purpose: To evaluate the effectiveness of the Swedish KCP in reducing acute knee injuries in soccer players at a nationwide level. Study Design: Descriptive epidemiology study. Methods: All licensed soccer players in Sweden are covered by the same insurance company. Using this insurance database, around 17,500 acute knee injuries that were reported to the insurance company between 2006 and 2015 were included in the study. By matching the number of licensed soccer players with the number of reported injuries each year, the annual incidence of knee and CL injuries was able to be calculated. To evaluate the spread of the KCP nationally, a questionnaire was sent to all 24 Swedish district football associations (FAs) with questions regarding KCP education. The number of downloads of the KCP mobile application (app) was obtained. Results: The incidence of CL injuries decreased during the study period for both male (from 2.9 to 2.4 per 1000 player-years) and female players (from 4.9 to 3.9 per 1000 player-years). The overall incidence of knee injuries decreased in both male (from 5.6 to 4.6 per 1000 player-years) and female players (from 8.7 to 6.4 per 1000 player-years). Comparing before and after the nationwide implementation of the KCP, there was a decrease in the incidence of CL injuries by 6% (rate ratio [RR], 0.94 [95% CI, 0.89-0.98]) in male players and 13% (RR, 0.87 [95% CI, 0.81-0.92]) in female players and a decrease in the incidence of knee injuries by 8% (RR, 0.92 [95% CI, 0.89-0.96]) and 21% (RR, 0.79 [95% CI, 0.75-0.83]), respectively (P amp;lt; .01 for all). This trend corresponded to a reduction of approximately 100 CL injuries each year in Sweden. A total of 21 of 24 district FAs held organized KCP educational courses during the study period. The percentage of district FAs holding KCP courses was between 46% and 79% each year. There were 101,236 downloads of the KCP app. Conclusion: The KCP can be considered partially implemented nationwide, and the incidence of knee and CL injuries has decreased in both sexes at a nationwide level.

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  • 6.
    Anderson, Judy E.
    et al.
    Department of Human Anatomy and Cell Science, University of Manitoba, Winnipeg, Canada; Manitoba Institute of Child's Health (MICH), University of Manitoba, Winnipeg, Canada.
    Hansen, Lise Lotte
    Institute of Human Genetics, University of Aarhus, Denmark.
    Mooren, Frank C.
    Department of Sports Medicine, Institute of Sport Sciences, University Giessen, Germany.
    Post, Markus
    Department of Sports Medicine, Institute of Sport Sciences, University Giessen, Germany.
    Hug, Hubert
    DSM Nutritional Products Ltd, Research & Development, Kaiseraugst, Switzerland.
    Zuse, Anne
    Manitoba Institute of Cell Biology (MICB), CancerCare Manitoba, 675 McDermot Ave. Rm. ON6010, Winnipeg, Man. R3E 0V9, Canada.
    Los, Marek Jan
    Manitoba Institute of Cell Biology, Cancer Care Manitoba; Manitoba Institute of Child Health; Department of Biochemistry and Medical Genetics; Department of Human Anatomy and Cell Science, University Manitoba, Winnipeg, Canada, .
    Methods and biomarkers for the diagnosis and prognosis of cancer and other diseases: Towards personalized medicine2006In: Drug resistance updates, ISSN 1368-7646, E-ISSN 1532-2084, Vol. 9, no 4-5, p. 198-210Article in journal (Refereed)
    Abstract [en]

    The rapid development of new diagnostic procedures, the mapping of the human genome, progress in mapping genetic polymorphisms, and recent advances in nucleic acid- and protein chip technologies are driving the development of personalized therapies. This breakthrough in medicine is expected to be achieved largely due to the implementation of "lab-on-the-chip" technology capable of performing hundreds, even thousands of biochemical, cellular and genetic tests on a single sample of blood or other body fluid. Focusing on a few disease-specific examples, this review discusses selected technologies and their combinations likely to be incorporated in the "lab-on-the-chip" and to provide rapid and versatile information about specific diseases entities. Focusing on breast cancer and after an overview of single-nucleofide polymorphism (SNP)-screening methodologies, we discuss the diagnostic and prognostic importance of SNPs. Next, using Duchenne muscular dystrophy (DMD) as an example, we provide a brief overview of powerful and innovative integration of traditional immuno-histochemistry techniques with advanced biophysical methods such as NMR-spectroscopy or Fourier-transformed infrared (FT-IR) spectroscopy. A brief overview of the challenges and opportunities provided by protein and aptamer microarrays follows. We conclude by highlighting novel and promising biochemical markers for the development of personalized treatment of cancer and other diseases: serum cytochrome c, cytokeratin-18 and -19 and their proteolytic fragments for the detection and quantitation of malignant tumor mass, tumor cell turn-over, inflammatory processes during hepatitis and Epstein-Barr virus (EBV)-induced hemophagocytic lymphohistiocytosis and apoptotic/necrotic cancer cell death. (c) 2006 Elsevier Ltd. All rights reserved.

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  • 7.
    Andersson, Jonny K.
    et al.
    Aspetar Orthopaedic and Sports Medicine Hospital, Doha, Qatar.
    Bengtsson, Håkan
    Linköping University, Department of Health, Medicine and Caring Sciences, Division of Prevention, Rehabilitation and Community Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Waldén, Markus
    Linköping University, Department of Health, Medicine and Caring Sciences, Division of Society and Health. Linköping University, Faculty of Medicine and Health Sciences. Hassleholm Kristianstad Hosp, Sweden.
    Karlsson, Jon
    Linköping University, Faculty of Medicine and Health Sciences. Univ Gothenburg, Sweden; Sahlgrens Univ Hosp, Sweden.
    Ekstrand, Jan
    Linköping University, Department of Health, Medicine and Caring Sciences, Division of Society and Health. Linköping University, Faculty of Medicine and Health Sciences.
    Hand, Wrist, and Forearm Injuries in Male Professional Soccer Players: A Prospective Cohort Study of 558 Team-Seasons From 2001-2002 to 2018-20192021In: The Orthopaedic Journal of Sports Medicine, ISSN 2325-9671, Vol. 9, no 1, article id 2325967120977091Article in journal (Refereed)
    Abstract [en]

    Background: The literature on upper extremity injuries in professional soccer players is scarce, and further insight into the onset and cause of these injuries as well as potential differences between goalkeepers and outfield players is important. Purpose: To investigate the epidemiology of hand, wrist, and forearm injuries in male professional soccer players between 2001 and 2019. Study Design: Descriptive epidemiology study. Methods: Between the 2001-2002 and 2018-2019 seasons, 120 European male soccer teams were followed prospectively for a varying number of seasons (558 team-seasons in total). Time-loss injuries and player-exposures to training sessions and matches were recorded on an individual basis in 6754 unique players. Injury incidence was reported as the number of injuries per 1000 player-hours, and between-group differences were analyzed using Z statistics and rate ratios (RRs) with 95% CIs. Between-group differences in layoff time were analyzed. Results: In total, 25,462 injuries were recorded, with 238 (0.9%) of these affecting the hand (71.4%; n = 170), wrist (16.8%; n = 40), and forearm (11.8%; n = 28), producing an incidence of 0.065 injuries per 1000 hours. A majority of the injuries were traumatic with an acute onset (98.7%; n = 235). Fractures were the most common injuries recorded (58.8%; n = 140), often involving the metacarpal bones (25.2%; n = 60) and phalanges (10.1%; n = 24). The injury incidence was significantly higher for goalkeepers (115 injuries; 0.265 per 1000 hours) compared with outfield players (123 injuries; 0.038 per 1000 hours) (RR, 7.0 [95% CI, 5.4-9.0]). Goalkeepers also had a significantly longer mean layoff time than outfield players (23 +/- 27 vs 15 +/- 27 days; P = .016). Conclusion: Injuries to the hand, wrist, and forearm constituted less than 1% of all time-loss injuries in male professional soccer players. Fractures were most common and constituted more than half of all injuries. Goalkeepers had a 7-fold higher incidence and an over 1-week longer mean layoff time compared with outfield players.

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  • 8.
    Arefin, Md Badrul
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Hematopoiesis and Developmental Biology. Linköping University, Faculty of Medicine and Health Sciences.
    Parvin, Farjana
    Linköping University, Department of Clinical and Experimental Medicine, Division of Hematopoiesis and Developmental Biology. Linköping University, Faculty of Medicine and Health Sciences.
    Bahrampour, Shahrzad
    Linköping University, Department of Clinical and Experimental Medicine, Division of Hematopoiesis and Developmental Biology. Linköping University, Faculty of Medicine and Health Sciences. Hosp Sick Children, Canada; Karolinska Inst, Sweden.
    Bivik Stadler, Caroline
    Linköping University, Department of Clinical and Experimental Medicine, Division of Hematopoiesis and Developmental Biology. Linköping University, Faculty of Medicine and Health Sciences.
    Thor, Stefan
    Linköping University, Department of Clinical and Experimental Medicine, Division of Hematopoiesis and Developmental Biology. Linköping University, Faculty of Medicine and Health Sciences. Univ Queensland, Australia; Univ Queensland, Australia.
    Drosophila Neuroblast Selection Is Gated by Notch, Snail, SoxB, and EMT Gene Interplay2019In: Cell Reports, E-ISSN 2211-1247, Vol. 29, no 11, p. 3636-3651.e3Article in journal (Refereed)
    Abstract [en]

    In the developing Drosophila central nervous system (CNS), neural progenitor (neuroblast [NB]) selection is gated by lateral inhibition, controlled by Notch signaling and proneural genes. However, proneural mutants still generate many NBs, indicating the existence of additional proneural genes. Moreover, recent studies reveal involvement of key epithelial-mesenchymal transition (EMT) genes in NB selection, but the regulatory interplay between Notch signaling and the EMT machinery is unclear. We find that SoxNeuro (SoxB family) and worniu (Snail family) are integrated with the Notch pathway, and constitute the missing proneural genes. Notch signaling, the proneural, SoxNeuro, and worniu genes regulate key EMT genes to orchestrate the NB selection process. Hence, we uncover an expanded lateral inhibition network for NB selection and demonstrate its link to key players in the EMT machinery. The evolutionary conservation of the genes involved suggests that the Notch-SoxB-Snail-EMT network may control neural progenitor selection in many other systems.

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  • 9.
    Astori, Audrey
    et al.
    Univ Hlth Network, Canada.
    Tingvall-Gustafsson, Johanna
    Lund Univ, Sweden.
    Kuruvilla, Jacob
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Molecular Medicine and Virology. Linköping University, Faculty of Medicine and Health Sciences.
    Coyaud, Etienne
    Univ Hlth Network, Canada.
    Laurent, Estelle M. N.
    Univ Hlth Network, Canada.
    Sunnerhagen, Maria
    Linköping University, Department of Physics, Chemistry and Biology, Chemistry. Linköping University, Faculty of Science & Engineering.
    Åhsberg, Josefine
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Molecular Medicine and Virology. Linköping University, Faculty of Medicine and Health Sciences.
    Ungerback, Jonas
    Lund Univ, Sweden.
    Strid, Tobias
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Cell Biology. Linköping University, Faculty of Medicine and Health Sciences.
    Sigvardsson, Mikael
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Molecular Medicine and Virology. Linköping University, Faculty of Medicine and Health Sciences. Lund Univ, Sweden.
    Raught, Brian
    Univ Hlth Network, Canada; Univ Toronto, Canada.
    Somasundaram, Rajesh
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Molecular Medicine and Virology. Linköping University, Faculty of Medicine and Health Sciences.
    ARID1a Associates with Lymphoid-Restricted Transcription Factors and Has an Essential Role in T Cell Development2020In: Journal of Immunology, ISSN 0022-1767, E-ISSN 1550-6606, Vol. 205, no 5, p. 1419-1432Article in journal (Refereed)
    Abstract [en]

    Maturation of lymphoid cells is controlled by the action of stage and lineage-restricted transcription factors working in concert with the general transcription and chromatin remodeling machinery to regulate gene expression. To better understand this functional interplay, we used Biotin Identification in human embryonic kidney cells to identify proximity interaction partners for GATA3, TCF7 (TCF1), SPI1, HLF, IKZF1, PAX5, ID1, and ID2. The proximity interaction partners shared among the lineagerestricted transcription factors included ARID1a, a BRG1-associated factor complex component. CUT&RUN analysis revealed that ARID1a shared binding with TCF7 and GATA3 at a substantial number of putative regulatory elements in mouse T cell progenitors. In support of an important function for ARID1a in lymphocyte development, deletion of Aridla in early lymphoid progenitors in mice resulted in a pronounced developmental arrest in early T cell development with a reduction of CD4(+)CD8(+) cells and a 20-fold reduction in thymic cellularity. Exploring gene expression patterns in DN3 cells from Wt and Aridla-deficient mice suggested that the developmental block resided in the DN3a to DN3b transition, indicating a deficiency in beta-selection. Our work highlights the critical importance of functional interactions between stage and lineage-restricted factors and the basic transcription machinery during lymphocyte differentiation.

  • 10.
    Atikuzzaman, Mohammad
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Medicine and Health Sciences.
    Sanz, Libia
    Instituto de Biomedicina de Valencia, CSIC, Valencia, Spain.
    Pla, Davinia
    Instituto de Biomedicina de Valencia, CSIC, Valencia, Spain.
    Alvarez-Rodriguez, Manuel
    Linköping University, Department of Clinical and Experimental Medicine, Division of Children's and Women's health. Linköping University, Faculty of Medicine and Health Sciences.
    Rubér, Marie
    Linköping University, Department of Clinical and Experimental Medicine, Division of Children's and Women's health. Linköping University, Faculty of Medicine and Health Sciences.
    Wright, Dominic
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Calvete, Juan J.
    Instituto de Biomedicina de Valencia, CSIC, Valencia, Spain.
    Rodriguez-Martinez, Heriberto
    Linköping University, Department of Clinical and Experimental Medicine, Division of Children's and Women's health. Linköping University, Faculty of Medicine and Health Sciences.
    Selection for higher fertility reflects in the seminal fluid proteome of modern domestic chicken2017In: Comparative Biochemistry and Physiology - Part D: Genomics and Proteomics, ISSN 1744-117X, E-ISSN 1878-0407, Vol. 21, p. 27-40Article in journal (Refereed)
    Abstract [en]

    The high egg-laying capacity of the modern domestic chicken (i.e. White Leghorn, WL) has arisen from the low egg-laying ancestor Red Junglefowl (RJF) via continuous trait selection and breeding. To investigate whether this long-term selection impacted the seminal fluid (SF)-proteome, 2DE electrophoresis-based proteomic analyses and immunoassays were conducted to map SF-proteins/cytokines in RJF, WL and a 9th generation Advanced Intercross Line (AIL) of RJF/WL-L13, including individual SF (n = 4, from each RJF, WL and AIL groups) and pools of the SF from 15 males of each group, analyzed by 2DE to determine their degree of intra-group (AIL, WL, and RJF) variability using Principal Component Analysis (PCA); respectively an inter-breed comparative analysis of intergroup fold change of specific SF protein spots intensity between breeds. The PCA clearly highlighted a clear intra-group similarity among individual roosters as well as a clear inter-group variability (e.g. between RJF, WL and AIL) validating the use of pools to minimize confounding individual variation. Protein expression varied considerably for processes related to sperm motility, nutrition, transport and survival in the female, including signaling towards immunomodulation. The major conserved SF-proteins were serum albumin and ovotransferrin. Aspartate aminotransferase, annexin A5, arginosuccinate synthase, glutathione S-transferase 2 and l-lactate dehydrogenase-A were RJF-specific. Glyceraldehyde-3-phosphate dehydrogenase appeared specific to the WL-SF while angiotensin-converting enzyme, γ-enolase, coagulation factor IX, fibrinogen α-chain, hemoglobin subunit α-D, lysozyme C, phosphoglycerate kinase, Src-substrate protein p85, tubulins and thioredoxin were AIL-specific. The RJF-SF contained fewer immune system process proteins and lower amounts of the anti-inflammatory/immunomodulatory TGF-β2 compared to WL and AIL, which had low levels- or lacked pro-inflammatory CXCL10 compared to RJF. The seminal fluid proteome differs between ancestor and modern chicken, with a clear enrichment of proteins and peptides related to immune-modulation for sperm survival in the female and fertility.

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  • 11.
    Azevedo, Carla
    et al.
    Lund Univ, Sweden.
    Teku, Gabriel
    Lund Univ, Sweden.
    Pomeshchik, Yuriy
    Lund Univ, Sweden.
    Reyes, Juan F.
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Neurobiology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Clinical pathology.
    Chumarina, Margarita
    Lund Univ, Sweden.
    Russ, Kaspar
    H Lundbeck & Co AS, Denmark; Lund Univ, Sweden.
    Savchenko, Ekaterina
    Lund Univ, Sweden.
    Hammarberg, Anna
    Lund Univ, Sweden.
    Lamas, Nuno Jorge
    Univ Minho, Portugal; PT Govt Associate Lab, Portugal; Ctr Hosp & Univ Porto, Portugal.
    Collin, Anna
    Reg Skane Off Med Serv, Sweden.
    Gouras, Gunnar K.
    Lund Univ, Sweden.
    Klementieva, Oxana
    Lund Univ, Sweden.
    Hallbeck, Martin
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Neurobiology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Clinical pathology.
    Taipa, Ricardo
    Ctr Hosp Univ Porto, Portugal.
    Vihinen, Mauno
    Lund Univ, Sweden.
    Roybon, Laurent
    Lund Univ, Sweden.
    Parkinsons disease and multiple system atrophy patient iPSC-derived oligodendrocytes exhibit alpha-synuclein-induced changes in maturation and immune reactive properties2022In: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 119, no 12, article id e2111405119Article in journal (Refereed)
    Abstract [en]

    Limited evidence has shed light on how aSYN proteins affect the oligodendrocyte phenotype and pathogenesis in synucleinopathies that include Parkinsons disease (PD) and multiple system atrophy (MSA). Here, we investigated early transcriptomic changes within PD and MSA O4(+) oligodendrocyte lineage cells (OLCs) generated from patient-induced pluripotent stem cells (iPSCs). We found impaired maturation of PD and MSA O4(+) OLCs compared to controls. This phenotype was associated with changes in the human leukocyte antigen (HLA) genes, the immunoproteasome subunit PSMB9, and the complement component C4b for aSYN p.A53T and MSA O4(+) OLCs, but not in SNCA(trip) O4(+) OLCs despite high levels of aSYN assembly formation. Moreover, SNCA overexpression resulted in the development of O4(+) OLCs, whereas exogenous treatment with aSYN species led to significant toxicity. Notably, transcriptome profiling of genes encoding proteins forming Lewy bodies and glial cytoplasmic inclusions revealed clustering of PD aSYN p.A53T O4(+) OLCs with MSA O4(+) OLCs. Our work identifies early phenotypic and pathogenic changes within human PD and MSA O4(+) OLCs.

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  • 12.
    Aziz, Mubashir
    et al.
    Islamia Univ Bahawalpur, Pakistan.
    Ejaz, Syeda Abida
    Islamia Univ Bahawalpur, Pakistan.
    Zargar, Seema
    King Saud Univ, Saudi Arabia.
    Akhtar, Naveed
    Islamia Univ Bahawalpur, Pakistan.
    Aborode, Abdullahi Tunde
    Mississippi State Univ, MS 39759 USA.
    Wani, Tanveer A.
    King Saud Univ, Saudi Arabia.
    Batiha, Gaber El-Saber
    Damanhour Univ, Egypt.
    Siddique, Farhan
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering. Royal Inst Med Sci RIMS, Pakistan.
    Alqarni, Mohammed
    Taif Univ, Saudi Arabia.
    Akintola, Ashraf Akintayo
    Kyungpook Natl Univ, South Korea.
    Deep Learning and Structure-Based Virtual Screening for Drug Discovery against NEK7: A Novel Target for the Treatment of Cancer2022In: Molecules, ISSN 1431-5157, E-ISSN 1420-3049, Vol. 27, no 13, article id 4098Article in journal (Refereed)
    Abstract [en]

    NIMA-related kinase7 (NEK7) plays a multifunctional role in cell division and NLRP3 inflammasone activation. A typical expression or any mutation in the genetic makeup of NEK7 leads to the development of cancer malignancies and fatal inflammatory disease, i.e., breast cancer, non-small cell lung cancer, gout, rheumatoid arthritis, and liver cirrhosis. Therefore, NEK7 is a promising target for drug development against various cancer malignancies. The combination of drug repurposing and structure-based virtual screening of large libraries of compounds has dramatically improved the development of anticancer drugs. The current study focused on the virtual screening of 1200 benzene sulphonamide derivatives retrieved from the PubChem database by selecting and docking validation of the crystal structure of NEK7 protein (PDB ID: 2WQN). The compounds library was subjected to virtual screening using Auto Dock Vina. The binding energies of screened compounds were compared to standard Dabrafenib. In particular, compound 762 exhibited excellent binding energy of -42.67 kJ/mol, better than Dabrafenib (-33.89 kJ/mol). Selected drug candidates showed a reactive profile that was comparable to standard Dabrafenib. To characterize the stability of protein-ligand complexes, molecular dynamic simulations were performed, providing insight into the molecular interactions. The NEK7-Dabrafenib complex showed stability throughout the simulated trajectory. In addition, binding affinities, pIC50, and ADMET profiles of drug candidates were predicted using deep learning models. Deep learning models predicted the binding affinity of compound 762 best among all derivatives, which supports the findings of virtual screening. These findings suggest that top hits can serve as potential inhibitors of NEK7. Moreover, it is recommended to explore the inhibitory potential of identified hits compounds through in-vitro and in-vivo approaches.

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  • 13.
    Babacic, Haris
    et al.
    Karolinska Inst, Sweden.
    Christ, Wanda
    Karolinska Inst, Sweden.
    Araujo, Jose Eduardo
    Karolinska Inst, Sweden.
    Mermelekas, Georgios
    Karolinska Inst, Sweden.
    Sharma, Nidhi
    Karolinska Inst, Sweden.
    Tynell, Janne
    Karolinska Inst, Sweden.
    Garcia, Marina
    Karolinska Inst, Sweden.
    Varnaite, Renata
    Karolinska Inst, Sweden.
    Asgeirsson, Hilmir
    Karolinska Univ Hosp, Sweden; Karolinska Inst, Sweden.
    Glans, Hedvig
    Karolinska Inst, Sweden; Karolinska Univ Hosp, Sweden.
    Lehtioe, Janne
    Karolinska Inst, Sweden.
    Gredmark-Russ, Sara
    Karolinska Inst, Sweden; Karolinska Univ Hosp, Sweden; Lab Mol Infect Med Sweden MIMS, Sweden.
    Klingström, Jonas
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Molecular Medicine and Virology. Linköping University, Faculty of Medicine and Health Sciences. Karolinska Inst, Sweden.
    Pernemalm, Maria
    Karolinska Inst, Sweden; Karolinska Inst, Sweden.
    Comprehensive proteomics and meta-analysis of COVID-19 host response2023In: Nature Communications, E-ISSN 2041-1723, Vol. 14, no 1, article id 5921Article in journal (Refereed)
    Abstract [en]

    COVID-19 is characterised by systemic immunological perturbations in the human body, which can lead to multi-organ damage. Many of these processes are considered to be mediated by the blood. Therefore, to better understand the systemic host response to SARS-CoV-2 infection, we performed systematic analyses of the circulating, soluble proteins in the blood through global proteomics by mass-spectrometry (MS) proteomics. Here, we show that a large part of the soluble blood proteome is altered in COVID-19, among them elevated levels of interferon-induced and proteasomal proteins. Some proteins that have alternating levels in human cells after a SARS-CoV-2 infection in vitro and in different organs of COVID-19 patients are deregulated in the blood, suggesting shared infection-related changes.The availability of different public proteomic resources on soluble blood proteome alterations leaves uncertainty about the change of a given protein during COVID-19. Hence, we performed a systematic review and meta-analysis of MS global proteomics studies of soluble blood proteomes, including up to 1706 individuals (1039 COVID-19 patients), to provide concluding estimates for the alteration of 1517 soluble blood proteins in COVID-19. Finally, based on the meta-analysis we developed CoViMAPP, an open-access resource for effect sizes of alterations and diagnostic potential of soluble blood proteins in COVID-19, which is publicly available for the research, clinical, and academic community. Baba & ccaron;ic et al. performed systematic analyses of blood proteins in COVID-19 patients through mass-spectrometry proteomics, showing that a large part of the soluble blood proteome is altered. The authors then developed an open-access resource, CoViMAPP, for meta-analysis of MS proteomics studies of COVID-19 patients.

  • 14.
    Baeza, Gabriela
    Linköping University, Department of Physics, Chemistry and Biology.
    X-ray Crystallographic Structure of theMurine Norovirus protease at 1.66 Å Resolutionand Functional Studies of the β-ribbon2011Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In humans, noroviruses (NVs) cause acute epidemic and viral gastroenteritis. NVs do not only infect humans; viruseshave also been found in pigs, cows, sheep, mice and dogs. The focus in this project has been on the murine norovirus(MNV). MNV is a member of the viral family Caliciviridae and it consists of a single-stranded, positive sense RNAgenome. The genome includes three open reading frames (ORFs), ORF1 encodes for a polyprotein that consists of theprecursor to the 6-7 non-structural (NS) proteins. The polyprotein is cleaved by the NS6 protease. The NS6 isresponsible for all the cleaving in ORF1 and that makes it an attractive target for antiviral drugs. The NS6 proteinstructure has been determined at 1.66 Å resolution using X-ray diffraction techniques. Surprisingly, the electrondensity map revealed density for a peptide bound in the active site. The peptide had a length of 7 residues andoriginated from the C-terminus of another chain in an adjacent asymmetric unit. The active site triad was composed ofthe conserved residues; histidine 30, aspargine 54 and cysteine 139, however in the structure the cysteine 139 ismutated to an alanine to inactivate the protease. Activity assays were performed to probe the importance of the residuein position 109 in the β-ribbon located close to the active site. The three full-length constructs with the mutations;I109A, I109S and I109T were found to have less activity than the full-length wt (1-183). A truncated protease, lacking9 residues in the C-terminus, also had less activity. This indicates that the terminal residues are also important foractivity.

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  • 15. Order onlineBuy this publication >>
    Bahrampour, Shahrzad
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Genetic mechanisms regulating proliferation and cell specification in the Drosophila embryonic CNS2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The central nervous system (CNS) consists of an enormous number of cells, and large cellular variance, integrated into an elaborate network. The CNS is the most complex animal organ, and therefore its establishment must be controlled by many different genetic programs. Considering the high level of complexity in the human CNS, addressing issues related to human neurodevelopment represents a major challenge. Since comparative studies have revealed that neurodevelopmental programs are well conserved through evolution, on both the genetic and functional levels, studies on invertebrate neurodevelopmental programs are often translatable to vertebrates. Indeed, the basis of our current knowledge about vertebrate CNS development has been greatly aided by studies on invertebrates, and in particular on the Drosophila melanogaster (fruit fly) model system.

    This thesis attempted to identify novel genes regulating neural cell specification and proliferation in the CNS, using the Drosophila model system. Moreover, I aimed to address how those genes govern neural progenitor cells (neuroblasts; NBs) to obtain/maintain their stemness identity and proliferation capacity, and how they drive NBs through temporal windows and series of programmed asymmetric division, which gradually reduces their stemness identity in favor of neural differentiation, resulting in appropriate lineage progression. In the first project, we conducted a forward genetic screen in Drosophila embryos, aimed at isolating genes involved in regulation of neural proliferation and specification, at the single cell resolution. By taking advantage of the restricted expression of the neuropeptide FMRFa in the last-born cell of the NB lineage 5-6T, the Ap4 neuron, we could monitor the entire lineage progression. This screen succeeded in identifying 43 novel genes controlling different aspects of CNS development. One of the genes isolated, Ctr9, displayed extra Ap4/FMRFa neurons. Ctr9 encodes a component of the RNA polymerase II complex Paf1, which is involved in a number of transcriptional processes. The Paf1C, including Ctr9, is highly conserved from yeast to human, and in the past couple of years, its importance for transcription has become increasingly appreciated. However, studies in the Drosophila system have been limited. In the screen, we isolated the first mutant of Drosophila Ctr9 and conducted the first detailed phenotypic study on its function in the Drosophila embryonic CNS. Loss of function of Ctr9 leads to extra NB numbers, higher proliferation ratio and lower expression of neuropeptides. Gene expression analysis identified several other genes regulated by Ctr9, which may explain the Ctr9 mutant phenotypes. In summary, we identified Ctr9 as an essential gene for proper CNS development in Drosophila, and this provides a platform for future study on the Drosophila Paf1C. Another interesting gene isolated in the screen was worniou (wor), a member of the Snail family of transcription factors. In contrast to Ctr9, whichdisplayed additional Ap4/FMRFa neurons, wor mutants displayed a loss of these neurons. Previous studies in our group have identified many genes acting to stop NB lineage progression, but how NBs are pushed to proliferate and generate their lineages was not well known. Since wor may constitute a “driver” of proliferation, we decided to study it further. Also, we identified five other transcription factors acting together with Wor as pro-proliferative in both NBs and their daughter cells. These “drivers” are gradually replaced by the previously identified late-acting “stoppers.” Early and late factors regulate each other and the cell cycle, and thereby orchestrate proper neural lineage progression.

    List of papers
    1. Novel Genes Involved in Controlling Specification of Drosophila FMRFamide Neuropeptide Cells
    Open this publication in new window or tab >>Novel Genes Involved in Controlling Specification of Drosophila FMRFamide Neuropeptide Cells
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    2015 (English)In: Genetics, ISSN 0016-6731, E-ISSN 1943-2631, Vol. 200, no 4, p. 1229-1244Article in journal (Refereed) Published
    Abstract [en]

    The expression of neuropeptides is often extremely restricted in the nervous system, making them powerful markers for addressing cell specification . In the developing Drosophila ventral nerve cord, only six cells, the Ap4 neurons, of some 10,000 neurons, express the neuropeptide FMRFamide (FMRFa). Each Ap4/FMRFa neuron is the last-born cell generated by an identifiable and well-studied progenitor cell, neuroblast 5-6 (NB5-6T). The restricted expression of FMRFa and the wealth of information regarding its gene regulation and Ap4 neuron specification makes FMRFa a valuable readout for addressing many aspects of neural development, i.e., spatial and temporal patterning cues, cell cycle control, cell specification, axon transport, and retrograde signaling. To this end, we have conducted a forward genetic screen utilizing an Ap4-specific FMRFa-eGFP transgenic reporter as our readout. A total of 9781 EMS-mutated chromosomes were screened for perturbations in FMRFa-eGFP expression, and 611 mutants were identified. Seventy-nine of the strongest mutants were mapped down to the affected gene by deficiency mapping or whole-genome sequencing. We isolated novel alleles for previously known FMRFa regulators, confirming the validity of the screen. In addition, we identified novel essential genes, including several with previously undefined functions in neural development. Our identification of genes affecting most major steps required for successful terminal differentiation of Ap4 neurons provides a comprehensive view of the genetic flow controlling the generation of highly unique neuronal cell types in the developing nervous system.

    Place, publisher, year, edition, pages
    Genetics Society of America, 2015
    Keywords
    Drosophila; CNS development; neural cell fate specification; forward genetic screening; FMRFamide
    National Category
    Clinical Medicine
    Identifiers
    urn:nbn:se:liu:diva-121318 (URN)10.1534/genetics.115.178483 (DOI)000359917000020 ()26092715 (PubMedID)
    Available from: 2015-09-16 Created: 2015-09-14 Last updated: 2019-03-13Bibliographically approved
    2. Ctr9, a Key Component of the Paf1 Complex, Affects Proliferation and Terminal Differentiation in the Developing Drosophila Nervous System
    Open this publication in new window or tab >>Ctr9, a Key Component of the Paf1 Complex, Affects Proliferation and Terminal Differentiation in the Developing Drosophila Nervous System
    2016 (English)In: G3: Genes, Genomes, Genetics, E-ISSN 2160-1836, Vol. 6, no 10, p. 3229-3239Article in journal (Refereed) Published
    Abstract [en]

    The Paf1 protein complex (Paf1C) is increasingly recognized as a highly conserved and broadly utilized regulator of a variety of transcriptional processes. These include the promotion of H3K4 and H3K36 trimethylation, H2BK123 ubiquitination, RNA Pol II transcriptional termination, and also RNA-mediated gene silencing. Paf1C contains five canonical protein components, including Paf1 and Ctr9, which are critical for overall complex integrity, as well as Rtf1, Leo1, and Cdc73/Parafibromin(Hrpt2)/Hyrax. In spite of a growing appreciation for the importance of Paf1C from yeast and mammalian studies, there has only been limited work in Drosophila. Here, we provide the first detailed phenotypic study of Ctr9 function in Drosophila. We found that Ctr9 mutants die at late embryogenesis or early larval life, but can be partly rescued by nervous system reexpression of Ctr9. We observed a number of phenotypes in Ctr9 mutants, including increased neuroblast numbers, increased nervous system proliferation, as well as downregulation of many neuropeptide genes. Analysis of cell cycle and regulatory gene expression revealed upregulation of the E2f1 cell cycle factor, as well as changes in Antennapedia and Grainy head expression. We also found reduction of H3K4me3 modification in the embryonic nervous system. Genome-wide transcriptome analysis points to additional downstream genes that may underlie these Ctr9 phenotypes, revealing gene expression changes in Notch pathway target genes, cell cycle genes, and neuropeptide genes. In addition, we find significant effects on the gene expression of metabolic genes. These findings reveal that Ctr9 is an essential gene that is necessary at multiple stages of nervous system development, and provides a starting point for future studies of the Paf1C in Drosophila.

    Place, publisher, year, edition, pages
    Genetics Society of America, 2016
    Keywords
    neuroblast, lineage tree, cell cycle, epigenetics, terminal differentiation, FlyBook
    National Category
    Genetics
    Identifiers
    urn:nbn:se:liu:diva-132856 (URN)10.1534/g3.116.034231 (DOI)000386581200018 ()27520958 (PubMedID)
    Note

    Funding Agencies|Swedish Research Council [621-2013-5258]; Knut and Alice Wallenberg Foundation [KAW2011.0165]; Swedish Cancer Foundation [120531]; Swedish Royal Academy of Sciences

    Available from: 2016-12-06 Created: 2016-11-30 Last updated: 2024-01-17
    3. Neural Lineage Progression Controlled by a Temporal Proliferation Program.
    Open this publication in new window or tab >>Neural Lineage Progression Controlled by a Temporal Proliferation Program.
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    2017 (English)In: Developmental Cell, ISSN 1534-5807, E-ISSN 1878-1551, Vol. 43, no 3, p. 332-348Article in journal (Refereed) Published
    Abstract [en]

    Great progress has been made in identifying transcriptional programs that establish stem cell identity. In contrast, we have limited insight into how these programs are down-graded in a timely manner to halt proliferation and allow for cellular differentiation. Drosophila embryonic neuroblasts undergo such a temporal progression, initially dividing to bud off daughters that divide once (type I), then switching to generating non-dividing daughters (type 0), and finally exiting the cell cycle. We identify six early transcription factors that drive neuroblast and type I daughter proliferation. Early factors are gradually replaced by three late factors, acting to trigger the type I→0 daughter proliferation switch and eventually to stop neuroblasts. Early and late factors regulate each other and four key cell-cycle genes, providing a logical genetic pathway for these transitions. The identification of this extensive driver-stopper temporal program controlling neuroblast lineage progression may have implications for studies in many other systems.less thanbr /greater than (Copyright © 2017 Elsevier Inc. All rights reserved.)

    Place, publisher, year, edition, pages
    Cell Press, 2017
    National Category
    Developmental Biology
    Identifiers
    urn:nbn:se:liu:diva-143117 (URN)10.1016/j.devcel.2017.10.004 (DOI)000414584300011 ()29112852 (PubMedID)
    Note

    Funding agencies: Swedish Research Council [621-2013-5258]; Knut and Alice Wallenberg Foundation [KAW2011.0165, KAW2012.0101]; Swedish Cancer Foundation [140780, 150633]

    Available from: 2017-11-20 Created: 2017-11-20 Last updated: 2017-11-20Bibliographically approved
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  • 16.
    Banerji, Shantanu
    et al.
    Manitoba Institute of Cell Biology, Winnipeg, Manitoba, Canada .
    Los, Marek Jan
    Manitoba Institute of Cell Biology, Cancer Care Manitoba; Manitoba Institute of Child Health; Department of Biochemistry and Medical Genetics; Department of Human Anatomy and Cell Science, University Manitoba, Winnipeg, Canada.
    Important differences between topoisomerase-I and -II targeting agents2006In: Cancer Biology & Therapy, ISSN 1538-4047, E-ISSN 1555-8576, Vol. 5, no 8, p. 965-966Article in journal (Other academic)
    Abstract [en]

    Commentary to: Activation of ATM and Histone H2AX Phosphorylation Induced by Mitoxantrone But Not by Topotecan is Prevented by the Antioxidant N-acetyl-L-Cysteine Xuan Huang, Akira Kurose, Toshiki Tanaka, Frank Traganos, Wei Dai and Zbigniew Darzynkiewicz

     

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  • 17. Order onlineBuy this publication >>
    Bergkvist, Liza
    Linköping University, Department of Physics, Chemistry and Biology, Chemistry. Linköping University, Faculty of Science & Engineering.
    Amyloid-β and lysozyme proteotoxicity in Drosophila: Beneficial effects of lysozyme and serum amyloid P component in models of Alzheimer’s disease and lysozyme amyloidosis2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In the work presented this thesis, two different conditions that are classified as protein misfolding diseases: Alzheimer's disease and lysozyme amyloidosis and proteins that could have a beneficial effect in these diseases, have been studied using Drosophila melanogaster, commonly known as the fruit fly. The fruit fly has been used for over 100 years to study and better understand fundamental biological processes. Although the fruit fly, unlike humans, is an invertebrate, many of its central biological mechanisms are very similar to ours. The first transgenic flies were designed in the early 1980s, and since then, the fruit fly has been one of the most widely used model organisms in studies on the effects of over-expressed human proteins in a biological system; one can regard the fly as a living, biological test tube. For  most proteins, it is necessary that they fold into a three-dimensional structure to function properly. But sometimes the folding goes wrong; this may be due to mutations that make the protein unstable and subject to misfolding. A misfolded protein molecule can then aggregate with other misfolded proteins. In Alzheimer's disease, which is the most common form of dementia, protein aggregates are present in the brains of patients. These aggregates are composed of the amyloid-β (Aβ) peptide, a small peptide of around 42 amino acids which is cleaved from the larger, membrane-bound, protein AβPP by two different enzymes, BACE1 and γ-secretase. In the first part of this thesis, two different fly models for Alzheimer’s disease were used: the Aβ fly model, which directly expresses the Aβ peptide, and the AβPP-BACE1 fly model, in which all the components necessary to produce the Aβ peptide in the fly are expressed in the fly central nervous system (CNS). The two different fly models were compared and the results show that a significantly smaller amount of the Aβ peptide is needed to achieve the same, or an even greater, toxic effect in the AβPP-BACE1 model compared to the Aβ model. In the second part of the thesis, these two fly models for Alzheimer’s disease were again used, but now to investigate whether lysozyme, a protein involved in our innate immune system, can counteract the toxic effect of Aβ generated in the fly models. And indeed, lysozyme is able to save the flies from Aβ-induced toxicity. Aβ and lysozyme were found to interact with each other in vivo. The second misfolding disease studied in this thesis is lysozyme amyloidosis. It is a rare, dominantly inherited amyloid disease in which mutant variants of lysozyme give rise to aggregates, weighing up to several kilograms, that accumulate around the kidneys and liver, eventually leading to organ failure. In the third part of this thesis, a fly model for lysozyme amyloidosis was used to study the effect of co-expressing the serum amyloid P component (SAP), a protein that is part of all protein aggregates found within this disease class. SAP is able to rescue the toxicity induced by expressing the mutant variant of lysozyme, F57I, in the fly's CNS. To further investigate how SAP was able to do this, double-expressing lysozyme flies, which exhibit stronger disease phenotypes than those of the single-expressing lysozyme flies previously studied, were used in the fourth part of this thesis. SAP was observed to reduce F57I toxicity and promote F57I to form aggregates with more distinct amyloid characteristics. In conclusion, the work included in this thesis demonstrates that: i) Aβ generated from AβPP processing in the fly CNS results in higher proteotoxicity compared with direct expression of Aβ from the transgene, ii) lysozyme can prevent Aβ proteotoxicity in Drosophila and could thus be a potential therapeutic molecule to treat Alzheimer’s disease and iii) in a Drosophila model of lysozyme amyloidosis, SAP can prevent toxicity from the disease-associated lysozyme variant F57I and promote formation of aggregated lysozyme morphotypes with amyloid properties; this is important to take into account when a reduced level of SAP is considered as a treatment strategy for lysozyme amyloidosis.

    List of papers
    1. A beta PP processing results in greater toxicity per amount of A beta(1-42) than individually expressed and secreted A beta(1-42) in Drosophila melanogaster
    Open this publication in new window or tab >>A beta PP processing results in greater toxicity per amount of A beta(1-42) than individually expressed and secreted A beta(1-42) in Drosophila melanogaster
    2016 (English)In: BIOLOGY OPEN, ISSN 2046-6390, Vol. 5, no 8, p. 1030-1039Article in journal (Refereed) Published
    Abstract [en]

    The aggregation of the amyloid-beta (A beta) peptide into fibrillar deposits has long been considered the key neuropathological hallmark of Alzheimers disease (AD). A beta peptides are generated from proteolytic processing of the transmembrane A beta precursor protein (A beta PP) via sequential proteolysis through the beta-secretase activity of beta-site A beta PP-cleaving enzyme (BACE1) and by the intramembranous enzyme gamma-secretase. For over a decade, Drosophila melanogaster has been used as a model organism to study AD, and two different approaches have been developed to investigate the toxicity caused by AD-associated gene products in vivo. In one model, the A beta peptide is directly over-expressed fused to a signal peptide, allowing secretion of the peptide into the extracellular space. In the other model, human A beta PP is co-expressed with human BACE1, resulting in production of the A beta peptide through the processing of A beta PP by BACE1 and by endogenous fly gamma-secretase. Here, we performed a parallel study of flies that expressed the A beta(1-42) peptide alone or that co-expressed A beta PP and BACE1. Toxic effects (assessed by eye phenotype, longevity and locomotor assays) and levels of the A beta(1-42), A beta(1-40) and A beta(1-38) peptides were examined. Our data reveal that the toxic effect per amount of detected A beta(1-42) peptide was higher in the flies co-expressing A beta PP and BACE1 than in the A beta(1-42)-expressing flies, and that the co-existence of A beta(1-42) and A beta(1-40) in the flies co-expressing A beta PP and BACE1 could be of significant importance to the neurotoxic effect detected in these flies. Thus, the toxicity detected in these two fly models seems to have different modes of action and is highly dependent on how and where the peptide is generated rather than on the actual level of the A beta(1-42) peptide in the flies. This is important knowledge that needs to be taken into consideration when using Drosophila models to investigate disease mechanisms or therapeutic strategies in AD research.

    Place, publisher, year, edition, pages
    COMPANY OF BIOLOGISTS LTD, 2016
    Keywords
    Alzheimers disease; Amyloid-beta (A beta); A beta PP processing; Drosophila melanogaster; Proteotoxicity
    National Category
    Medical Biotechnology (with a focus on Cell Biology (including Stem Cell Biology), Molecular Biology, Microbiology, Biochemistry or Biopharmacy)
    Identifiers
    urn:nbn:se:liu:diva-131685 (URN)10.1242/bio.017194 (DOI)000382304400003 ()27387531 (PubMedID)
    Note

    Funding Agencies|Torsten Soderbergs Stiftelse [M26/11]; Alzheimer Foundation [03-069]; Dementia Foundation; Ahlen Foundation; Gamla Tjanarinnor [2015-00187]

    Available from: 2016-10-03 Created: 2016-09-30 Last updated: 2017-05-16
    2. Beneficial effects of increased lysozyme levels in Alzheimer’s disease modelled in Drosophila melanogaster
    Open this publication in new window or tab >>Beneficial effects of increased lysozyme levels in Alzheimer’s disease modelled in Drosophila melanogaster
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    2016 (English)In: The FEBS Journal, ISSN 1742-464X, E-ISSN 1742-4658, Vol. 283, no 19, p. 3508-3522Article in journal (Refereed) Published
    Abstract [en]

    Genetic polymorphisms of immune genes that associate with higher risk to develop Alzheimer’s disease (AD) have led to an increased research interest on the involvement of the immune system in AD pathogenesis. A link between amyloid pathology and immune gene expression was suggested in a genome-wide gene expression study of transgenic amyloid mouse models. In this study, the gene expression of lysozyme, a major player in the innate immune system, was found to be increased in a comparable pattern as the amyloid pathology developed in transgenic mouse models of AD. A similar pattern was seen at protein levels of lysozyme in human AD brain and CSF, but this lysozyme pattern was not seen in a tau transgenic mouse model. Lysozyme was demonstrated to be beneficial for different Drosophila melanogaster models of AD. In flies that expressed Aβ1-42 or AβPP together with BACE1 in the eyes, the rough eye phenotype indicative of toxicity was completely rescued by coexpression of lysozyme. In Drosophila flies bearing the Aβ1-42 variant with the Arctic gene mutation, lysozyme increased the fly survival and decreased locomotor dysfunction dose dependently. An interaction between lysozyme and Aβ1-42 in the Drosophila eye was discovered. We propose that the increased levels of lysozyme, seen in mouse models of AD and in human AD cases, were triggered by Aβ1-42 and caused a beneficial effect by binding of lysozyme to toxic species of Aβ1-42, which prevented these from exerting their toxic effects. These results emphasize the possibility of lysozyme as biomarker and therapeutic target for AD.

    Place, publisher, year, edition, pages
    John Wiley & Sons, 2016
    Keywords
    Alzheimer’s disease, amyloid-β, Drosophila, lysozyme
    National Category
    Genetics Medical Genetics Developmental Biology Bioinformatics and Systems Biology Medical Biotechnology (with a focus on Cell Biology (including Stem Cell Biology), Molecular Biology, Microbiology, Biochemistry or Biopharmacy)
    Identifiers
    urn:nbn:se:liu:diva-131796 (URN)10.1111/febs.13830 (DOI)000386033700001 ()27562772 (PubMedID)
    Available from: 2016-10-07 Created: 2016-10-07 Last updated: 2018-03-20Bibliographically approved
    3. Serum Amyloid P Component Ameliorates Neurological Damage Caused by Expressing a Lysozyme Variant in the Central Nervous System of Drosophila melanogaster
    Open this publication in new window or tab >>Serum Amyloid P Component Ameliorates Neurological Damage Caused by Expressing a Lysozyme Variant in the Central Nervous System of Drosophila melanogaster
    2016 (English)In: PLOS ONE, E-ISSN 1932-6203, Vol. 11, no 7, p. e0159294-Article in journal (Refereed) Published
    Abstract [en]

    Lysozyme amyloidosis is a hereditary disease in which mutations in the gene coding for lysozyme leads to misfolding and consequently accumulation of amyloid material. To improve understanding of the processes involved we expressed human wild type (WT) lysozyme and the disease-associated variant F57I in the central nervous system (CNS) of a Drosophila melanogaster model of lysozyme amyloidosis, with and without co-expression of serum amyloid p component (SAP). SAP is known to be a universal constituent of amyloid deposits and to associate with lysozyme fibrils. There are clear indications that SAP may play an important role in lysozyme amyloidosis, which requires further elucidation. We found that flies expressing the amyloidogenic variant F57I in the CNS have a shorter lifespan than flies expressing WT lysozyme. We also identified apoptotic cells in the brains of F57I flies demonstrating that the flies neurological functions are impaired when F57I is expressed in the nerve cells. However, co-expression of SAP in the CNS prevented cell death and restored the F57I flies lifespan. Thus, SAP has the apparent ability to protect nerve cells from damage caused by F57I. Furthermore, it was found that co-expression of SAP prevented accumulation of insoluble forms of lysozyme in both WT- and F57I-expressing flies. Our findings suggest that the F57I mutation affects the aggregation process of lysozyme resulting in the formation of cytotoxic species and that SAP is able to prevent cell death in the F57I flies by preventing accumulation of toxic F57I structures.

    Place, publisher, year, edition, pages
    PUBLIC LIBRARY SCIENCE, 2016
    National Category
    Developmental Biology
    Identifiers
    urn:nbn:se:liu:diva-131183 (URN)10.1371/journal.pone.0159294 (DOI)000380169300043 ()27428539 (PubMedID)
    Note

    Funding Agencies|Swedish Research Council; Soderberg foundation [M26/11]; Linkoping University Neurobiology Center

    Available from: 2016-09-19 Created: 2016-09-12 Last updated: 2021-06-14
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    Amyloid-β and lysozyme proteotoxicity in Drosophila: Beneficial effects of lysozyme and serum amyloid P component in models of Alzheimer’s disease and lysozyme amyloidosis
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  • 18.
    Bergkvist, Liza
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Chemistry. Linköping University, Faculty of Science & Engineering.
    Sandin, Linnea
    Linköping University, Department of Clinical and Experimental Medicine, Division of Cell Biology. Linköping University, Faculty of Medicine and Health Sciences.
    Kågedal, Katarina
    Linköping University, Department of Clinical and Experimental Medicine, Division of Cell Biology. Linköping University, Faculty of Medicine and Health Sciences.
    Brorsson, Ann-Christin
    Linköping University, Department of Physics, Chemistry and Biology, Chemistry. Linköping University, Faculty of Science & Engineering.
    A beta PP processing results in greater toxicity per amount of A beta(1-42) than individually expressed and secreted A beta(1-42) in Drosophila melanogaster2016In: BIOLOGY OPEN, ISSN 2046-6390, Vol. 5, no 8, p. 1030-1039Article in journal (Refereed)
    Abstract [en]

    The aggregation of the amyloid-beta (A beta) peptide into fibrillar deposits has long been considered the key neuropathological hallmark of Alzheimers disease (AD). A beta peptides are generated from proteolytic processing of the transmembrane A beta precursor protein (A beta PP) via sequential proteolysis through the beta-secretase activity of beta-site A beta PP-cleaving enzyme (BACE1) and by the intramembranous enzyme gamma-secretase. For over a decade, Drosophila melanogaster has been used as a model organism to study AD, and two different approaches have been developed to investigate the toxicity caused by AD-associated gene products in vivo. In one model, the A beta peptide is directly over-expressed fused to a signal peptide, allowing secretion of the peptide into the extracellular space. In the other model, human A beta PP is co-expressed with human BACE1, resulting in production of the A beta peptide through the processing of A beta PP by BACE1 and by endogenous fly gamma-secretase. Here, we performed a parallel study of flies that expressed the A beta(1-42) peptide alone or that co-expressed A beta PP and BACE1. Toxic effects (assessed by eye phenotype, longevity and locomotor assays) and levels of the A beta(1-42), A beta(1-40) and A beta(1-38) peptides were examined. Our data reveal that the toxic effect per amount of detected A beta(1-42) peptide was higher in the flies co-expressing A beta PP and BACE1 than in the A beta(1-42)-expressing flies, and that the co-existence of A beta(1-42) and A beta(1-40) in the flies co-expressing A beta PP and BACE1 could be of significant importance to the neurotoxic effect detected in these flies. Thus, the toxicity detected in these two fly models seems to have different modes of action and is highly dependent on how and where the peptide is generated rather than on the actual level of the A beta(1-42) peptide in the flies. This is important knowledge that needs to be taken into consideration when using Drosophila models to investigate disease mechanisms or therapeutic strategies in AD research.

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  • 19. Order onlineBuy this publication >>
    Bivik Stadler, Caroline
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Genetic pathways controlling CNS development: The role of Notch signaling in regulating daughter cell proliferation in Drosophila2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The human central nervous system (CNS) displays the greatest cellular diversity of any organ system, consisting of billions of neurons, of numerous cell sub-types, interconnected in a vast network. Given this enormous complexity, decoding the genetic programs controlling the multistep process of CNS development remains a major challenge. While great progress has been made with respect to understanding sub-type specification, considerably less is known regarding how the generation of the precise number of each sub-type is controlled.

    The aim of this thesis was to gain deeper knowledge into the regulatory programs controlling cell specification and proliferation. To address these questions I have studied the Drosophila embryonic CNS as a model system, to thereby be able to investigate the genetic mechanisms at high resolution. Despite the different size and morphology between the Drosophila and the mammalian CNS, the lineages of their progenitors share similarity. Importantly for this thesis, both species progenitors show elaborate variations in their proliferation modes, either giving rise to daughters that can directly differentiate into neurons or glia (type 0), divide once (type I), or multiple times (type II).

    The studies launched off with a comprehensive chemical forward genetic screen, for the very last born cell in the well-studied lineage of progenitor NB5-6T: the Ap4 neuron, which expresses the neuropeptide FMRFa. NB5-6T is a powerful model to use, because it undergoes a programmed type I>0 daughter cell proliferation switch. An FMRF-eGFP transgenic reporter was utilized as readout for successful terminal differentiation of Ap4/FMRFa and thereby proper lineage progression of the ∼20 cells generated. The strongest mutants were mapped to genes with both known and novel essential functions e.g., spatial and temporal patterning, cell cycle control, cell specification and chromatin modification. Subsequently, we focused on some of the genes that showed a loss of function phenotype with an excess of lineage cells. We found that Notch is critical for the type I>0 daughter cell proliferation switch in the NB5-6T lineage and globally as well. When addressing the broader relevance of these findings, and to further decipher the Notch pathway, we discovered that selective groups of E(spl) genes is controlling the switch in a close interplay with four key cell cycle factors: Cyclin E, String, E2F and Dacapo, in most if not all embryonic progenitors. The Notch mediation of the switch is likely to be by direct transcriptional regulation. Furthermore, another gene identified in the screen, sequoia, was investigated. The analysis revealed that sequoia is also controlling the daughter cell switch in the CNS, and this partly through context dependent interactions with the Notch pathway.

    Taken together, the findings presented in this thesis demonstrate that daughter cell proliferation switches in Drosophila neural lineages are genetically programmed, and that Notch contributes to the triggering of these events. Given that early embryonic processes is frequently shown to be evolutionary conserved, you can speculate that changeable daughter proliferation programs could be applied to mammals, and contribute to a broader understanding of proliferation processes in humans as well.

     

    List of papers
    1. Novel Genes Involved in Controlling Specification of Drosophila FMRFamide Neuropeptide Cells
    Open this publication in new window or tab >>Novel Genes Involved in Controlling Specification of Drosophila FMRFamide Neuropeptide Cells
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    2015 (English)In: Genetics, ISSN 0016-6731, E-ISSN 1943-2631, Vol. 200, no 4, p. 1229-1244Article in journal (Refereed) Published
    Abstract [en]

    The expression of neuropeptides is often extremely restricted in the nervous system, making them powerful markers for addressing cell specification . In the developing Drosophila ventral nerve cord, only six cells, the Ap4 neurons, of some 10,000 neurons, express the neuropeptide FMRFamide (FMRFa). Each Ap4/FMRFa neuron is the last-born cell generated by an identifiable and well-studied progenitor cell, neuroblast 5-6 (NB5-6T). The restricted expression of FMRFa and the wealth of information regarding its gene regulation and Ap4 neuron specification makes FMRFa a valuable readout for addressing many aspects of neural development, i.e., spatial and temporal patterning cues, cell cycle control, cell specification, axon transport, and retrograde signaling. To this end, we have conducted a forward genetic screen utilizing an Ap4-specific FMRFa-eGFP transgenic reporter as our readout. A total of 9781 EMS-mutated chromosomes were screened for perturbations in FMRFa-eGFP expression, and 611 mutants were identified. Seventy-nine of the strongest mutants were mapped down to the affected gene by deficiency mapping or whole-genome sequencing. We isolated novel alleles for previously known FMRFa regulators, confirming the validity of the screen. In addition, we identified novel essential genes, including several with previously undefined functions in neural development. Our identification of genes affecting most major steps required for successful terminal differentiation of Ap4 neurons provides a comprehensive view of the genetic flow controlling the generation of highly unique neuronal cell types in the developing nervous system.

    Place, publisher, year, edition, pages
    Genetics Society of America, 2015
    Keywords
    Drosophila; CNS development; neural cell fate specification; forward genetic screening; FMRFamide
    National Category
    Clinical Medicine
    Identifiers
    urn:nbn:se:liu:diva-121318 (URN)10.1534/genetics.115.178483 (DOI)000359917000020 ()26092715 (PubMedID)
    Available from: 2015-09-16 Created: 2015-09-14 Last updated: 2019-03-13Bibliographically approved
    2. Control of neuronal cell fate and number by integration of distinct daughter cell proliferation modes with temporal progression
    Open this publication in new window or tab >>Control of neuronal cell fate and number by integration of distinct daughter cell proliferation modes with temporal progression
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    2012 (English)In: Development, ISSN 0950-1991, E-ISSN 1477-9129, Vol. 139, no 4, p. 678-689Article in journal (Refereed) Published
    Abstract [en]

    During neural lineage progression, differences in daughter cell proliferation can generate different lineage topologies. This is apparent in the Drosophila neuroblast 5-6 lineage (NB5-6T), which undergoes a daughter cell proliferation switch from generating daughter cells that divide once to generating neurons directly. Simultaneously, neural lineages, e.g. NB5-6T, undergo temporal changes in competence, as evidenced by the generation of different neural subtypes at distinct time points. When daughter proliferation is altered against a backdrop of temporal competence changes, it may create an integrative mechanism for simultaneously controlling cell fate and number. Here, we identify two independent pathways, Prospero and Notch, which act in concert to control the different daughter cell proliferation modes in NB5-6T. Altering daughter cell proliferation and temporal progression, individually and simultaneously, results in predictable changes in cell fate and number. This demonstrates that different daughter cell proliferation modes can be integrated with temporal competence changes, and suggests a novel mechanism for coordinately controlling neuronal subtype numbers.

    Place, publisher, year, edition, pages
    Company of Biologists, 2012
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-74790 (URN)10.1242/dev.074500 (DOI)000300259800005 ()
    Note

    funding agencies|Swedish Research Council||Knut and Alice Wallenberg foundation||Swedish Cancer Foundation||

    Available from: 2012-02-08 Created: 2012-02-08 Last updated: 2019-03-13
    3. Control of Neural Daughter Cell Proliferation by Multi-level Notch/Su(H)/E(spl)-HLH Signaling
    Open this publication in new window or tab >>Control of Neural Daughter Cell Proliferation by Multi-level Notch/Su(H)/E(spl)-HLH Signaling
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    2016 (English)In: PLOS Genetics, ISSN 1553-7390, E-ISSN 1553-7404, Vol. 12, no 4, article id e1005984Article in journal (Refereed) Published
    Abstract [en]

    The Notch pathway controls proliferation during development and in adulthood, and is frequently affected in many disorders. However, the genetic sensitivity and multi-layered transcriptional properties of the Notch pathway has made its molecular decoding challenging. Here, we address the complexity of Notch signaling with respect to proliferation, using the developing Drosophila CNS as model. We find that a Notch/Su(H)/E(spl)-HLH cascade specifically controls daughter, but not progenitor proliferation. Additionally, we find that different E(spl)-HLH genes are required in different neuroblast lineages. The Notch/Su(H)/E(spl)-HLH cascade alters daughter proliferation by regulating four key cell cycle factors: Cyclin E, String/Cdc25, E2f and Dacapo (mammalian p21(CIP1)/p27(KIP1)/p57(Kip2)). ChIP and DamID analysis of Su(H) and E(spl)-HLH indicates direct transcriptional regulation of the cell cycle genes, and of the Notch pathway itself. These results point to a multi-level signaling model and may help shed light on the dichotomous proliferative role of Notch signaling in many other systems.

    Place, publisher, year, edition, pages
    PUBLIC LIBRARY SCIENCE, 2016
    National Category
    Clinical Medicine
    Identifiers
    urn:nbn:se:liu:diva-128759 (URN)10.1371/journal.pgen.1005984 (DOI)000375231900032 ()27070787 (PubMedID)
    Note

    Funding Agencies|Knut and Alice Wallenberg Foundation [KAW2012.0101]; Swedish Research Council [621-2010-5214]; Swedish Cancer Foundation [120531]

    Available from: 2016-05-31 Created: 2016-05-30 Last updated: 2022-09-13
    4. sequoia controls the type I>0 daughter proliferation switch in the developing Drosophila nervous system
    Open this publication in new window or tab >>sequoia controls the type I>0 daughter proliferation switch in the developing Drosophila nervous system
    2016 (English)In: Development, ISSN 0950-1991, E-ISSN 1477-9129, Vol. 143, no 20, p. 3774-3784Article in journal (Refereed) Published
    Abstract [en]

    Neural progenitors typically divide asymmetrically to renew themselves, while producing daughters with more limited potential. In the Drosophila embryonic ventral nerve cord, neuroblasts initially produce daughters that divide once to generate two neurons/glia (type I proliferation mode). Subsequently, many neuroblasts switch to generating daughters that differentiate directly (type 0). This programmed type I>0 switch is controlled by Notch signaling, triggered at a distinct point of lineage progression in each neuroblast. However, how Notch signaling onset is gated was unclear. We recently identified Sequoia (Seq), a C2H2 zinc-finger transcription factor with homology to Drosophila Tramtrack (Ttk) and the positive regulatory domain (PRDM) family, as important for lineage progression. Here, we find that seq mutants fail to execute the type I>0 daughter proliferation switch and also display increased neuroblast proliferation. Genetic interaction studies reveal that seq interacts with the Notch pathway, and seq furthermore affects expression of a Notch pathway reporter. These findings suggest that seq may act as a context-dependent regulator of Notch signaling, and underscore the growing connection between Seq, Ttk, the PRDM family and Notch signaling.

    Place, publisher, year, edition, pages
    The Company of Biologists Ltd, 2016
    Keywords
    Lineage tree, Cell cycle, Asymmetric division, Combinatorial control, Notch
    National Category
    Cell and Molecular Biology Biochemistry and Molecular Biology Cell Biology Medical Biotechnology
    Identifiers
    urn:nbn:se:liu:diva-132739 (URN)10.1242/dev.139998 (DOI)000393452500013 ()27578794 (PubMedID)
    Note

    Funding agencies: Swedish Research Council (Vetenskapsradet); Knut and Alice Wallenberg Foundation (Knut och Alice Wallenbergs Stiftelse); Swedish Cancer Foundation (Cancerfonden)

    Available from: 2016-11-22 Created: 2016-11-22 Last updated: 2019-03-13Bibliographically approved
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    Genetic pathways controlling CNS development: The role of Notch signaling in regulating daughter cell proliferation in Drosophila
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  • 20. Order onlineBuy this publication >>
    Blissing, Annica
    Linköping University, Department of Physics, Chemistry and Biology, Chemistry. Linköping University, Faculty of Science & Engineering.
    Thiopurine S-methyltransferase - characterization of variants and ligand binding2017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Thiopurine S-methyltransferase (TPMT) belongs to the Class I S-adenosylmethionine-dependent methyltransferase (SAM-MT) super family of structurally related proteins. Common to the members of this large protein family is the catalysis of methylation reactions using S-adenosylmethionine (SAM) as a methyl group donor, although SAM-MTs act on a wide range of different substrates and carry out numerous biologically important functions. While the natural function of TPMT is unknown, this enzyme is involved in the metabolism of thiopurines, a class of pharmaceutical substances administered in treatment of immune-related disorders. Specifically, methylation by TPMT inactivates thiopurines and their metabolic intermediates, which reduces the efficacy of clinical treatment and increases the risk of adverse side effects. To further complicate matters, TPMT is a polymorphic enzyme with over 40 naturally occurring variants known to date, most of which exhibit lowered methylation activity towards thiopurines. Consequently, there are individual variations in TPMTmediated thiopurine inactivation, and the administered dose has to be adjusted prior to clinical treatment to avoid harmful side effects.

    Although the clinical relevance of TPMT is well established, few studies have investigated the molecular causes of the reduced methylation activity of variant proteins. In this thesis, the results of biophysical characterization of two variant proteins, TPMT*6 (Y180F) and TPMT*8 (R215H), are presented. While the properties of TPMT*8 were indistinguishable from those of the wild-type protein, TPMT*6 was found to be somewhat destabilized. Interestingly, the TPMT*6 amino acid substitution did not affect the functionality or folding pattern of the variant protein. Therefore, the decreased in vivo functionality reported for TPMT*6 is probably caused by increased proteolytic degradation in response to the reduced stability of this protein variant, rather than loss of function.

    Also presented herein are novel methodological approaches for studies of TPMT and its variants. Firstly, the advantages of using 8-anilinonaphthalene-1-sulfonic acid (ANS) to probe TPMT tertiary structure and active site integrity are presented. ANS binds exclusively to the native state of TPMT with high affinity (KD ~ 0.2 μm) and a 1:1 ratio. The stability of TPMT was dramatically increased by binding of ANS, which was shown to co-localize with the structurally similar adenine moiety of the cofactor SAM. Secondly, an enzyme activity assay based on isothermal titration calorimetry (ITC) is presented. Using this approach, the kinetics of 6-MP and 6-TG methylation by TPMT has been characterized.

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  • 21.
    Boberg, Andreas
    et al.
    Department of Microbiology, Tumor and Cell Biology, Karolinska Institute, Stockholm, Sweden.
    Stålnacke, Alexandra
    Etvax AB, Solna, Sweden.
    Bråve, Andreas
    Department of Microbiology, Tumor and Cell Biology, Karolinska Institute, Stockholm, Sweden.
    Hinkula, Jorma
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology. Linköping University, Faculty of Health Sciences.
    Wahren, Britta
    Department of Microbiology, Tumor and Cell Biology, Karolinska Institute, Stockholm, Sweden.
    Carlin, Nils
    Etvax AB, Solna, Sweden.
    Receptor binding by cholera toxin B-subunit and amino acid modification improves minimal peptide immunogenecity2012In: ISRN Molecular Biology, ISSN 2090-7907, Vol. 2012, article id 170676Article in journal (Refereed)
    Abstract [en]

    We increase our understanding of augmenting a cellular immune response, by using an HIV-1 protease-derived epitope (PR7584), and variants thereof, coupled to the C-terminal, of the B subunit of cholera toxin (CTB). Fusion proteins were used for immunizations of HLA-A0201 transgenic C57BL/6 mice. We observed different capacities to elicit a cellular immune response by peptides with additions of five to ten amino acids to the PR epitope. There was a positive correlation between the magnitude of the elicited cellular immune response and the capacity of the fusion protein to bind GM-1. This binding capacity is affected by its ability to form natural pentamers of CTB. Our results suggest that functional CTB pentamers containing a foreign amino acid-modified epitope is a novel way to overcome the limited cellular immunogenicity of minimal peptide antigens. This way of using a functional assay as readout for improved cellular immunogenicity might become highly valuable for difficult immunogens such as short peptides (epitopes).

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  • 22.
    Bohannon, Briana M.
    et al.
    Univ Miami, FL 33136 USA.
    de la Cruz, Alicia
    Univ Miami, FL 33136 USA.
    Wu, Xiaoan
    Univ Miami, FL 33136 USA.
    Jowais, Jessica J.
    Univ Miami, FL 33136 USA.
    Perez, Marta E.
    Univ Miami, FL 33136 USA.
    Liin, Sara
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Neurobiology. Linköping University, Faculty of Medicine and Health Sciences.
    Larsson, H. Peter
    Univ Miami, FL 33136 USA.
    Polyunsaturated fatty acid analogues differentially affect cardiac Na-V, Ca-V, and K-V channels through unique mechanisms2020In: eLIFE, E-ISSN 2050-084X, Vol. 9, article id e51453Article in journal (Refereed)
    Abstract [en]

    The cardiac ventricular action potential depends on several voltage-gated ion channels, including Na-V, Ca-V, and K-V channels. Mutations in these channels can cause Long QT Syndrome (LQTS) which increases the risk for ventricular fibrillation and sudden cardiac death. Polyunsaturated fatty acids (PUFAs) have emerged as potential therapeutics for LQTS because they are modulators of voltage-gated ion channels. Here we demonstrate that PUFA analogues vary in their selectivity for human voltage-gated ion channels involved in the ventricular action potential. The effects of specific PUFA analogues range from selective for a specific ion channel to broadly modulating cardiac ion channels from all three families (Na-V, Ca-V, and K-V). In addition, a PUFA analogue selective for the cardiac IKs channel (Kv7.1/KCNE1) is effective in shortening the cardiac action potential in human-induced pluripotent stem cell-derived cardiomyocytes. Our data suggest that PUFA analogues could potentially be developed as therapeutics for LQTS and cardiac arrhythmia.

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  • 23.
    Bojmar, Linda
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Medicine and Health Sciences.
    Metastatic Mechanisms in Malignant Tumors2015Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The ultimate cause of cancer related deaths is metastasis. This thesis is about three of the main human cancers; breast, colorectal and pancreatic cancer, that together account for more than 25% of the cancer-related deaths worldwide. The focus of the thesis is the spread of cancer, metastasis, and the aim was to investigate mechanisms that can be of importance for this process. We analyzed patient samples to validate the role of epithelialto-mesenchymal transition in vivo and found regulations of many related factors. However, these changes tend to fluctuate along the metastatic process, something which makes targeting complicated. We, moreover, focused on the influence of the tumor microenvironment for metastatic spread. In pancreatic cancer, the stroma constitutes the main part of many tumors. We analyzed the crosstalk between tumor and stromal cell and focused on the mediating inflammatory factor interleukin-1 (IL-1) and regulation of microRNAs. The results showed that the most commonly mutated factor in pancreatic cancer, KRAS, associates with the expression of IL-1 and subsequent activation of stromal cells. Blocking KRAS signaling together with IL-1 blockage give a more pronounced effect on in vitro proliferation and migration of cancer cells and suggests the use of a combination therapy. The cancer-associated activation of the stroma was found to be related to changes in microRNA expression. microRNA was analyzed separately in epithelial cells and stromal cells after microdissection of matched samples of primary and secondary tumors of breast and colorectal cancers. miR-214 and miR-199a were upregulated in stroma associated with progressive tumors and in pancreatic cancer stroma we could show that their expression alters the activation of stromal cells and thereby the growth and migratory ability of associated pancreatic tumor cells. In  breast and colorectal cancers we found several common microRNAs to be up- or downregulated in line with progression. We could show that one of these candidates, miR-18a, had a prognostic value in metastatic breast cancer. To further develop these studies we analyzed this microRNA in circulating microvesicles, i.e. exosomes, and investigated their role in the preparation of a pre-metastatic niche. MicroRNAs are stable biomarkers in the circulation, especially protected in exosomes, which can moreover specifically deliver their message to recipient cells. These studies facilitate the understanding of metastatic behavior and suggest new targets to stop cancer metastasis.

    List of papers
    1. The Role of MicroRNA-200 in Progression of Human Colorectal and Breast Cancer
    Open this publication in new window or tab >>The Role of MicroRNA-200 in Progression of Human Colorectal and Breast Cancer
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    2013 (English)In: PLOS ONE, E-ISSN 1932-6203, Vol. 8, no 12, p. 84815-Article in journal (Refereed) Published
    Abstract [en]

    The role of the epithelial-mesenchymal transition (EMT) in cancer has been studied extensively in vitro, but involvement of the EMT in tumorigenesis in vivo is largely unknown. We investigated the potential of microRNAs as clinical markers and analyzed participation of the EMT-associated microRNA-200 ZEB E-cadherin pathway in cancer progression. Expression of the microRNA-200 family was quantified by real-time RT-PCR analysis of fresh-frozen and microdissected formalin-fixed paraffin-embedded primary colorectal tumors, normal colon mucosa, and matched liver metastases. MicroRNA expression was validated by in situ hybridization and after in vitro culture of the malignant cells. To assess EMT as a predictive marker, factors considered relevant in colorectal cancer were investigated in 98 primary breast tumors from a treatment-randomized study. Associations between the studied EMTmarkers were found in primary breast tumors and in colorectal liver metastases. MicroRNA-200 expression in epithelial cells was lower in malignant mucosa than in normal mucosa, and was also decreased in metastatic compared to non-metastatic colorectal cancer. Low microRNA-200 expression in colorectal liver metastases was associated with bad prognosis. In breast cancer, low levels of microRNA-200 were related to reduced survival and high expression of microRNA-200 was predictive of benefit from radiotheraphy. MicroRNA-200 was associated with ER positive status, and inversely correlated to HER2 and overactivation of the PI3K/AKT pathway, that was associated with high ZEB1 mRNA expression. Our findings suggest that the stability of microRNAs makes them suitable as clinical markers and that the EMT-related microRNA-200 - ZEB - E-cadherin signaling pathway is connected to established clinical characteristics and can give useful prognostic and treatment-predictive information in progressive breast and colorectal cancers.

    Place, publisher, year, edition, pages
    Public Library of Science, 2013
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-103717 (URN)10.1371/journal.pone.0084815 (DOI)000328745100188 ()
    Available from: 2014-01-24 Created: 2014-01-24 Last updated: 2021-06-14
    2. IL-1α Expression in Pancreatic Ductal Adenocarcinoma Affects the Tumor Cell Migration and Is Regulated by the p38MAPK Signaling Pathway
    Open this publication in new window or tab >>IL-1α Expression in Pancreatic Ductal Adenocarcinoma Affects the Tumor Cell Migration and Is Regulated by the p38MAPK Signaling Pathway
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    2013 (English)In: PLOS ONE, E-ISSN 1932-6203, Vol. 8, no 8Article in journal (Refereed) Published
    Abstract [en]

    The interplay between the tumor cells and the surrounding stroma creates inflammation, which promotes tumor growth and spread. The inflammation is a hallmark for pancreatic adenocarcinoma (PDAC) and is to high extent driven by IL-1α. IL-1α is expressed and secreted by the tumor cells and exerting its effect on the stroma, i.e. cancer associated fibroblasts (CAF), which in turn produce massive amount of inflammatory and immune regulatory factors. IL-1 induces activation of transcription factors such as nuclear factor-κβ (NF-κβ), but also activator protein 1 (AP-1) via the small G-protein Ras. Dysregulation of Ras pathways are common in cancer as this oncogene is the most frequently mutated in many cancers. In contrast, the signaling events leading up to the expression of IL-1α by tumor cells are not well elucidated. Our aim was to examine the signaling cascade involved in the induction of IL-1α expression in PDAC. We found p38MAPK, activated by the K-Ras signaling pathway, to be involved in the expression of IL-1α by PDAC as blocking this pathway decreased both the gene and protein expression of IL-1α. Blockage of the P38MAPK signaling in PDAC also dampened the ability of the tumor cell to induce inflammation in CAFs. In addition, the IL-1α autocrine signaling regulated the migratory capacity of PDAC cells. Taken together, the blockage of signaling pathways leading to IL-1α expression and/or neutralization of IL-1α in the PDAC microenvironment should be taken into consideration as possible treatment or complement to existing treatment of this cancer.

    Place, publisher, year, edition, pages
    Public Library of Science, 2013
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-97445 (URN)10.1371/journal.pone.0070874 (DOI)000323097300061 ()
    Note

    Funding Agencies|Swedish Research Council|AI52731|VINNMER (Vinnova)||Medical Research Council of Southeast Sweden||Swedish Society of Medicine||

    Available from: 2013-09-12 Created: 2013-09-12 Last updated: 2021-06-14
    3. MicroRNA-199a and -214 as potential therapeutic targets in pancreatic stellate cells in pancreatic tumor
    Open this publication in new window or tab >>MicroRNA-199a and -214 as potential therapeutic targets in pancreatic stellate cells in pancreatic tumor
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    2016 (English)In: Oncotarget, E-ISSN 1949-2553, Vol. 7, no 13, p. 16396-16408Article in journal (Refereed) Published
    Abstract [en]

    Pancreatic stellate cells (PSCs) are the key precursor cells for cancer-associated fibroblasts (CAFs) in pancreatic tumor stroma. Although depletion of tumor stroma is debatable, attenuation of PSC activity is still an interesting strategy to treat pancreatic cancer. In this study, we explored miRNA as therapeutic targets in tumor stroma and found miR-199a-3p and miR-214-3p induced in patient-derived pancreatic CAFs as well as in TGF-β-activated human PSCs (hPSCs). Inhibition of miR-199a or miR-214 using their hairpin inhibitors in hPSCs significantly inhibited their TGFβ-induced differentiation (gene and protein levels of α-SMA, Collagen, PDGFβR), migration and proliferation. Furthermore, heterospheroids of Panc-1 and hPSCs were prepared, which attained smaller size when hPSCs were transfected with anti-miR-199a or -214 than those transfected with control anti-miR. The conditioned medium obtained from TGFβ-activated hPSCs induced tumor cell proliferation and endothelial cell tube formation, but these effects were abrogated when hPSCs were transfected with anti-miR-199a or miR-214. Moreover, IPA analyses revealed signaling pathways related to miR-199a (TP53, mTOR, Smad1) and miR-214 (PTEN, Bax, ING4). Taken together, this study reveals miR-199a-3p and miR-214-3p as major regulators of PSC activation and PSC-induced pro-tumoral effects, representing them as key therapeutic targets in PSCs in pancreatic cancer.

    Place, publisher, year, edition, pages
    Impact press, 2016
    National Category
    Cancer and Oncology Cell and Molecular Biology Medical Biotechnology (with a focus on Cell Biology (including Stem Cell Biology), Molecular Biology, Microbiology, Biochemistry or Biopharmacy)
    Identifiers
    urn:nbn:se:liu:diva-122828 (URN)10.18632/oncotarget.7651 (DOI)000375692900085 ()
    Note

    Funding agencies: Swedish Research Council, Stockholm, Sweden [K7/60501283]

    Vid tiden för disputationen förelåg publikationen endast som manuskript

    Available from: 2015-11-26 Created: 2015-11-26 Last updated: 2024-01-17
    4. miR-18a is regulated between progressive compartments of cancers, and incorporated in exosomes with the potential of creating premetastatic niches and predict cancer outcome
    Open this publication in new window or tab >>miR-18a is regulated between progressive compartments of cancers, and incorporated in exosomes with the potential of creating premetastatic niches and predict cancer outcome
    Show others...
    2015 (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    The ultimate cause of death for many cancer patients is the spread of the cancer via metastasis. Even so, there are still a lack of knowledge regarding the metastasis process. This study was performed to investigate the role of metastamirs in exosomes and their metastatic patterns. We used the well-established isogeneic murine cancer model of low metastatic 67NR cells, mimicking luminal/basal breast tumors, and highly metastatic 4T1 cells with characteristics of basal breast  tumors. We studied the exosomal properties and pre-metastatic effects in this metastasis model and compared human materials and exosomes of several other tumor types. Our data clearly demonstrated that exosomes from the highly metastatic cells home to the metastatic organs of their parental cells whereas exosomes from cells with low metastatic potential mostly located to lymph nodes. The exosome protein cargos also resembled their parental cells and potentially affects their target organs, and cells, differently. Furthermore, the exosomes from the highly metastatic cells had a more pronounced effect on tumor growth and pre-metastatic changes than the low metastatic exosomes. The microRNA-18a, a predictor of metastasis, was present to a higher extent in metastatic exosomes as compared to low metastatic exosomes, and altered the tumor progressive properties. Our findings support the role of exomirs as important players in the metastatic process, the value as biomarkers and potential therapeutic targets.

    National Category
    Cancer and Oncology Cell and Molecular Biology Medical Biotechnology (with a focus on Cell Biology (including Stem Cell Biology), Molecular Biology, Microbiology, Biochemistry or Biopharmacy)
    Identifiers
    urn:nbn:se:liu:diva-122829 (URN)
    Available from: 2015-11-26 Created: 2015-11-26 Last updated: 2018-01-10Bibliographically approved
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  • 24.
    Bojmar, Linda
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Medicine and Health Sciences.
    Zhang, Haiying
    Children’s Cancer and Blood Foundation Laboratories, Departments of Pediatrics, and Cell and Developmental Biology, Drukier Institute for Children’s Health, Meyer Cancer Center, Weill Cornell Medical College, New York, USA.
    Costa da Silva, Bruno
    Children’s Cancer and Blood Foundation Laboratories, Departments of Pediatrics, and Cell and Developmental Biology, Drukier Institute for Children’s Health, Meyer Cancer Center, Weill Cornell Medical College, New York, USA.
    Karlsson, Elin
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Oncology.
    Olsson, Hans
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Pathology and Clinical Genetics.
    Vincent, Theresa
    Departments of Physiology and Biophysics and Cell and Developmental Biology, Weill Cornell Medical College, New York, USA / Department of Medicine, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden.
    Larsson, Marie
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Stål, Olle
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Oncology.
    Lyden, David
    Children’s Cancer and Blood Foundation Laboratories, Departments of Pediatrics, and Cell and Developmental Biology, Drukier Institute for Children’s Health, Meyer Cancer Center, Weill Cornell Medical College, New York, USA.
    Sandström, Per
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Surgery in Linköping.
    miR-18a is regulated between progressive compartments of cancers, and incorporated in exosomes with the potential of creating premetastatic niches and predict cancer outcome2015Manuscript (preprint) (Other academic)
    Abstract [en]

    The ultimate cause of death for many cancer patients is the spread of the cancer via metastasis. Even so, there are still a lack of knowledge regarding the metastasis process. This study was performed to investigate the role of metastamirs in exosomes and their metastatic patterns. We used the well-established isogeneic murine cancer model of low metastatic 67NR cells, mimicking luminal/basal breast tumors, and highly metastatic 4T1 cells with characteristics of basal breast  tumors. We studied the exosomal properties and pre-metastatic effects in this metastasis model and compared human materials and exosomes of several other tumor types. Our data clearly demonstrated that exosomes from the highly metastatic cells home to the metastatic organs of their parental cells whereas exosomes from cells with low metastatic potential mostly located to lymph nodes. The exosome protein cargos also resembled their parental cells and potentially affects their target organs, and cells, differently. Furthermore, the exosomes from the highly metastatic cells had a more pronounced effect on tumor growth and pre-metastatic changes than the low metastatic exosomes. The microRNA-18a, a predictor of metastasis, was present to a higher extent in metastatic exosomes as compared to low metastatic exosomes, and altered the tumor progressive properties. Our findings support the role of exomirs as important players in the metastatic process, the value as biomarkers and potential therapeutic targets.

  • 25.
    Bolshakova, A.V.
    et al.
    Institute of Cytology, Russian Academy of Sciences, St. Petersburg, Russia.
    Petukhova, O.A.
    Institute of Cytology, Russian Academy of Sciences, St. Petersburg, Russia.
    Pinaev, G.P.
    Institute of Cytology, Russian Academy of Sciences, St. Petersburg, Russia.
    Magnusson, Karl-Erik
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Comparative analysis of subcellular fractionation methods for revealing a-actinin 1 and a-actinin 4 in A431 cells2009In: Cell and Tissue Biology, ISSN 1990-519X, Vol. 3, no 2, p. 188-197Article in journal (Refereed)
    Abstract [en]

    a-Actinin 1 and a-actinin 4 are actin-binding proteins with shared structural functions that are responsible for the regulation of several processes in the cell. Based on previous data on the different distribution of these proteins in the nucleus and cytoplasm, we have studied in detail the presence of a-actinin 1 and a-actinin 4 in subcellular fractions in the A431 cells spread on fibronectin. The detection of a-actinins in some particular fractions has been shown to depend on the method of lysis, as well as whether the preliminary low-temperature freezing of cells was used. The application of various fractionation methods has allowed us to conclude that a-actinin 4 is present in all cytoplasmic and nuclear subfractions, whereas, in addition to in the cytoplasm, a-actinin 1 can also be revealed in the nuclear envelope fraction.

  • 26.
    Booy, Evan P.
    et al.
    Manitoba Institute of Cell Biology, and Department of Biochemistry and Medical Genetics, Univ. Manitoba, Winnipeg, Canada.
    Johar, Dina
    Manitoba Institute of Cell Biology,CancerCare Manitoba, University of Manitoba, ON6010-675 McDermot Ave., Winnipeg, MB, R3E 0V9, Canada; Department of Biochemistry and Medical Genetics, University of Manitoba, Winnipeg, Canada .
    Maddika, Srilekha
    Manitoba Institute of Cell Biology,CancerCare Manitoba, University of Manitoba, ON6010-675 McDermot Ave., Winnipeg, MB, R3E 0V9, Canada; Department of Biochemistry and Medical Genetics, University of Manitoba, Winnipeg, Canada .
    Pirzada, Hasan
    Manitoba Institute of Cell Biology,CancerCare Manitoba, University of Manitoba, ON6010-675 McDermot Ave., Winnipeg, MB, R3E 0V9, Canada.
    Sahib, Mickey M.
    Department of Oral Biology, University of Manitoba, Winnipeg, Canada .
    Gehrke, Iris
    Manitoba Institute of Cell Biology,CancerCare Manitoba, University of Manitoba, ON6010-675 McDermot Ave., Winnipeg, MB, R3E 0V9, Canada.
    Loewen, Shauna
    Manitoba Institute of Cell Biology,CancerCare Manitoba, University of Manitoba, ON6010-675 McDermot Ave., Winnipeg, MB, R3E 0V9, Canada; Department of Biochemistry and Medical Genetics, University of Manitoba, Winnipeg, Canada .
    Louis, Sherif F.
    Manitoba Institute of Cell Biology,CancerCare Manitoba, University of Manitoba, ON6010-675 McDermot Ave., Winnipeg, MB, R3E 0V9, Canada.
    Kadkhoda, Kamran
    Manitoba Institute of Cell Biology,CancerCare Manitoba, University of Manitoba, ON6010-675 McDermot Ave., Winnipeg, MB, R3E 0V9, Canada; Department of Biochemistry and Medical Genetics, University of Manitoba, Winnipeg, Canada .
    Mowat, Michael
    Manitoba Institute of Cell Biology,CancerCare Manitoba, University of Manitoba, ON6010-675 McDermot Ave., Winnipeg, MB, R3E 0V9, Canada; Department of Biochemistry and Medical Genetics, University of Manitoba, Winnipeg, Canada .
    Los, Marek Jan
    Manitoba Institute of Cell Biology, Cancer Care Manitoba; Manitoba Institute of Child Health; Department of Biochemistry and Medical Genetics; Department of Human Anatomy and Cell Science, University Manitoba, Winnipeg, Canada, .
    Monoclonal and bispecific antibodies as novel therapeutics2006In: Archivum Immunologiae et Therapiae Experimentalis, ISSN 0004-069X, E-ISSN 1661-4917, Vol. 54, no 2, p. 85-101Article in journal (Refereed)
    Abstract [en]

    Gene amplification, over-expression, and mutation of growth factors, or the receptors themselves, causes increased signaling through receptor kinases, which has been implicated in many human cancers and is associated with poor prognosis. Tumor growth has been shown to be decreased by interrupting this process of extensive growth factor-mediated signaling by directly targeting either the surface receptor or the ligand and thereby preventing cell survival and promoting apoptosis. Monoclonal antibodies have long been eyed as a potential new class of therapeutics targeting cancer and other diseases. Antibody-based therapy initially entered clinical practice when trastuzumab/Herceptin became the first clinically approved drug against an oncogene product as a well-established blocking reagent for tumors with hyperactivity of epidermal growth factor signaling pathways. In the first part of this review we explain basic terms related to the development of antibody-based drugs, give a brief historic perspective of the field, and also touch on topics such as the "humanization of antibodies" or creation of hybrid antibodies. The second part of the review gives an overview of the clinical usage of bispecific antibodies and antibodies "armed" with cytotoxic agents or enzymes. Further within this section, cancer-specific, site-specific, or signaling pathway-specific therapies are discussed in detail. Among other antibody-based therapeutic products, we discuss: Avastin (bevacizumab), CG76030, Theragyn (pemtumomab), daclizumab (Zenapax), TriAb, MDX-210, Herceptin (trastuzumab), panitumumab (ABX-EGF), mastuzimab (EMD-72000), Erbitux (certuximab, IMC225), Panorex (edrecolomab), STI571, CeaVac, Campath (alemtuizumab), Mylotarg (gemtuzumab, ozogamicin), and many others. The end of the review deliberates upon potential problems associated with cancer immunotherapy.

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  • 27.
    Borg, Mathias
    Linköping University, Department of Physics, Chemistry and Biology.
    Study of the insulin-like peptide 3 in human platelets2009Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The insulin-like 3 peptide is autocrine/paracrine insulin-related hormone with a size of approximately 6kDa [1]. It mediates through a leucine richG-coupled receptor named LGR8. INSL3 is mainly expressed in human Leydig cells and is directly responsible for migration of the testis during the pre-natal period in maledevelopment. [2]

    INSL3 mRNA has recently been verified in human platelets whereas no mRNA has been detected for LGR8 (by Sanofi-Aventis GmbH in Frankfurt,Germany), indicating that INSL3 might be released through paracrine functions at sites of platelet adhesion and aggregation upon a vascular injury.Furthermore, has activated platelets been shown to translate essential proteins upon activation, in a term called “signal-dependent protein synthesis”.The B-Cell lymphoma-3 protein (BCL-3) is an example of such a protein [3], and there is a possibility that INSL3 might be also.

    In this thesis we wanted to detect the relaxin- like peptide 3 hormone (INSL3). (Its function, location and the timeframe of its release, when/if it issecreated in stimulated platelets).The source of platelet-derived INSL3 can be found with Western blotting and Enzyme immunoassay.

    Detection of the insulin-like 3 peptide in human platelets turned out to be a difficult challenge due to the small amount of INSL3 secretion uponplatelet activation; hence the total amount of INSL3 produced might be below detection limit.

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  • 28.
    Borsa, Baris Ata
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Hernandez, Luiza I.
    Linköping University, Department of Biomedical and Clinical Sciences. Linköping University, Faculty of Medicine and Health Sciences. SOMAprobes, Science and Technology Park of Gipuzkoa, Donostia-San Sebastian, Spain.
    Jiménez, Tania
    SOMAprobes, Science and Technology Park of Gipuzkoa, Donostia-San Sebastian, Spain.
    Tellapragada, Chaitanya
    Division of Clinical Microbiology, Department of Laboratory Medicine, Karolinska Institutet, Stockholm, Sweden; Clinical Microbiology, Karolinska University Hospital, Stockholm, Sweden.
    Giske, Christian G
    Division of Clinical Microbiology, Department of Laboratory Medicine, Karolinska Institutet, Stockholm, Sweden; Clinical Microbiology, Karolinska University Hospital, Stockholm, Sweden.
    Hernandez, Frank J
    Linköping University, Faculty of Science & Engineering. Linköping University, Department of Physics, Chemistry and Biology, Biology.
    Therapeutic-oligonucleotides activated by nucleases (TOUCAN): A nanocarrier system for the specific delivery of clinical nucleoside analogues.2023In: Journal of Controlled Release, ISSN 0168-3659, E-ISSN 1873-4995, Vol. 361, p. 260-269Article in journal (Refereed)
    Abstract [en]

    Nucleoside analogues have been in clinical use since 1960s and they are still used as the first therapeutic option for several cancers and viral infections, due to their high therapeutic efficacy. However, their wide clinical acceptance has been limited due to their high toxicity and severe side effects to patients. Herein, we report on a nanocarrier system that delivers nucleosides analogues in a target-specific manner, making nucleoside-based therapeutics safer and with the possibility to be used in other human conditions. This system, named, Therapeutic OligonUCleotides Activated by Nucleases" (TOUCAN) combines: i) the recognition power of oligonucleotides as substrates, ii) the use of nucleases as enzymatic biomarkers and iii) the clinical efficacy of nucleoside analogues, in a single approach. As a proof-of-concept, we report on a TOUCAN that is activated by a specific nuclease produced by bacteria and releases a therapeutic nucleoside, floxuridine. We demonstrate, for the first time, that, by incorporating a therapeutic nucleoside analogue into oligonucleotide probes, we can specifically inhibit bacterial growth in cultures. In this study, Staphylococcus aureus was selected as the targeted bacteria and the TOUCAN strategy successfully inhibited its growth with minimal inhibitory concentration (MIC) values ranging from 0.62 to 40 mg/L across all tested strains. Moreover, our results indicate that the intravenous administration of TOUCANs at a dose of 20 mg/kg over a 24-h period is a highly effective method for treating bacterial infections in a mouse model of pyomyositis. Importantly, no signs of toxicity were observed in our in vitro and in vivo studies. This work can significantly impact the current management of bacterial infections, laying the grounds for the development of a different class of antibiotics. Furthermore, it can provide a safer delivery platform for clinical nucleoside therapeutics in any human conditions, such as cancer and viral infection, where specific nuclease activity has been reported.

  • 29.
    Brewer-Jensen, Paul D.
    et al.
    Univ N Carolina, NC 27599 USA.
    Reyes, Yaoska
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Molecular Medicine and Virology. Linköping University, Faculty of Medicine and Health Sciences. Natl Autonomous Univ Nicaragua, Nicaragua.
    Becker-Dreps, Sylvia
    Univ N Carolina, NC 27599 USA; Univ N Carolina, NC 27599 USA.
    Gonzalez, Fredman
    Natl Autonomous Univ Nicaragua, Nicaragua.
    Mallory, Michael L.
    Univ N Carolina, NC 27599 USA.
    Gutierrez, Lester
    Natl Autonomous Univ Nicaragua, Nicaragua.
    Zepeda, Omar
    Natl Autonomous Univ Nicaragua, Nicaragua.
    Centeno, Edwing
    Natl Autonomous Univ Nicaragua, Nicaragua.
    Vielot, Nadja
    Univ N Carolina, NC 27599 USA.
    Diez-Valcarce, Marta
    US Ctr Dis Control & Prevent, GA 30329 USA.
    Vinje, Jan
    US Ctr Dis Control & Prevent, GA 30329 USA.
    Baric, Ralph
    Univ N Carolina, NC 27599 USA.
    Lindesmith, Lisa C.
    Univ N Carolina, NC 27599 USA.
    Bucardo, Filemon
    Natl Autonomous Univ Nicaragua, Nicaragua.
    Norovirus Infection in Young Nicaraguan Children Induces Durable and Genotype-Specific Antibody Immunity2022In: Viruses, E-ISSN 1999-4915, Vol. 14, no 9, article id 2053Article in journal (Refereed)
    Abstract [en]

    There are significant challenges to the development of a pediatric norovirus vaccine, mainly due to the antigenic diversity among strains infecting young children. Characterizing human norovirus serotypes and understanding norovirus immunity in naive children would provide key information for designing rational vaccine platforms. In this study, 26 Nicaraguan children experiencing their first norovirus acute gastroenteritis (AGE) episode during the first 18 months of life were investigated. We used a surrogate neutralization assay that measured antibodies blocking the binding of 13 different norovirus virus-like particles (VLPs) to histo-blood group antigens (HBGAs) in pre- and post-infection sera. To assess for asymptomatic norovirus infections, stools from asymptomatic children were collected monthly, screened for norovirus by RT-qPCR and genotyped by sequencing. Seroconversion of an HBGA-blocking antibody matched the infecting genotype in 25 (96%) of the 26 children. A subset of 13 (50%) and 4 (15%) of the 26 children experienced monotypic GII and GI seroconversion, respectively, strongly suggesting a type-specific response in naive children, and 9 (35%) showed multitypic seroconversion. The most frequent pairing in multitypic seroconversion (8/12) were GII.4 Sydney and GII.12 noroviruses, both co-circulating at the time. Blocking antibody titers to these two genotypes did not correlate with each other, suggesting multiple exposure rather than cross-reactivity between genotypes. In addition, GII titers remained consistent for at least 19 months post-infection, demonstrating durable immunity. In conclusion, the first natural norovirus gastroenteritis episodes in these young children were dominated by a limited number of genotypes and induced responses of antibodies blocking binding of norovirus VLPs in a genotype-specific manner, suggesting that an effective pediatric norovirus vaccine likely needs to be multivalent and include globally dominant genotypes. The duration of protection from natural infections provides optimism for pediatric norovirus vaccines administered early in life.

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  • 30.
    Burek, M.
    et al.
    Department of Immunology and Cell Biology, University of Münster, Münster, Germany.
    Maddika, Subbareddy
    Manitoba Institute of Cell Biology, Cancer Care Manitoba; Department of Biochemistry and Medical Genetics,University of Manitoba, Winnipeg, Canada .
    Burek, C. J.
    Department of Immunology and Cell Biology, University of Münster, Münster, Germany.
    Daniel, P. T.
    Department of Hematology, Oncology and Tumor Immunology, Charité, Berlin, Germany.
    Schulze-Osthoff, Klaus
    nstitute of Molecular Medicine, University of Düsseldorf, Düsseldorf, Germany .
    Los, Marek Jan
    Manitoba Institute of Cell Biology, Cancer Care Manitoba; Manitoba Institute of Child Health; Department of Biochemistry and Medical Genetics; Department of Human Anatomy and Cell Science, University Manitoba, Winnipeg, Canada, .
    Apoptin-induced cell death is modulated by Bcl-2 family members and is Apaf-1dependent2006In: Oncogene, ISSN 0950-9232, E-ISSN 1476-5594, Vol. 25, no 15, p. 2213-2222Article in journal (Refereed)
    Abstract [en]

    Apoptin, a chicken anemia virus-derived protein, selectively induces apoptosis in transformed but not in normal cells, thus making it a promising candidate as a novel anticancer therapeutic. The mechanism of apoptin-induced apoptosis is largely unknown. Here, we report that contrary to previous assumptions, Bcl-2 and Bcl-x(L) inhibit apoptin-induced cell death in several tumor cell lines. In contrast, deficiency of Bax conferred resistance, whereas Bax expression sensitized cells to apoptin-induced death. Cell death induction by apoptin was associated with cytochrome c release from mitochondria as well as with caspase-3 and -7 activation. Benzyloxy-carbonyl-Val-Ala-Asp-fluoromethyl ketone, a broad spectrum caspase inhibitor, was highly protective against apoptin-induced cell death. Apoptosis induced by apoptin required Apaf-1, as immortalized Apaf-1-deficient fibroblasts as well as tumor cells devoid of Apaf-1 were strongly protected. Thus, our data indicate that apoptin-induced apoptosis is not only Bcl-2- and caspase dependent, but also engages an Apaf-1 apoptosome-mediated mitochondrial death pathway.

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  • 31.
    Burocziova, Monika
    et al.
    Czech Acad Sci, Czech Republic.
    Burdova, Kamila
    Czech Acad Sci, Czech Republic.
    Martinikova, Andra S.
    Czech Acad Sci, Czech Republic.
    Kasparek, Petr
    Czech Acad Sci, Czech Republic.
    Kleiblova, Petra
    Charles Univ Prague, Czech Republic.
    Danielsen, Stine A.
    Oslo Univ Hosp, Norway; Oslo Univ Hosp, Norway.
    Borecka, Marianna
    Charles Univ Prague, Czech Republic.
    Jenikova, Gabriela
    Czech Acad Sci, Czech Republic.
    Janeckova, Lucie
    Czech Acad Sci, Czech Republic.
    Pavel, Jozef
    Czech Acad Sci, Czech Republic.
    Zemankova, Petra
    Charles Univ Prague, Czech Republic.
    Schneiderova, Michaela
    Charles Univ Prague, Czech Republic; Gen Fac Hosp Prague, Czech Republic.
    Schwarzova, Lucie
    Gen Fac Hosp Prague, Czech Republic; Charles Univ Prague, Czech Republic.
    Ticha, Ivana
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Medicine and Health Sciences. Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Oncology. Gen Fac Hosp Prague, Czech Republic; Charles Univ Prague, Czech Republic.
    Sun, Xiao-Feng
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Oncology.
    Jiraskova, Katerina
    ASCR, Czech Republic.
    Liska, Vaclav
    Charles Univ Prague, Czech Republic.
    Vodickova, Ludmila
    ASCR, Czech Republic; Charles Univ Prague, Czech Republic; Charles Univ Prague, Czech Republic.
    Vodicka, Pavel
    ASCR, Czech Republic; Charles Univ Prague, Czech Republic; Charles Univ Prague, Czech Republic.
    Sedlacek, Radislav
    Czech Acad Sci, Czech Republic.
    Kleibl, Zdenek
    Charles Univ Prague, Czech Republic.
    Lothe, Ragnhild A.
    Oslo Univ Hosp, Norway; Oslo Univ Hosp, Norway.
    Korinek, Vladimir
    Czech Acad Sci, Czech Republic.
    Macurek, Libor
    Czech Acad Sci, Czech Republic.
    Truncated PPM1D impairs stem cell response to genotoxic stress and promotes growth of APC-deficient tumors in the mouse colon2019In: Cell Death and Disease, ISSN 2041-4889, E-ISSN 2041-4889, Vol. 10, article id 818Article in journal (Refereed)
    Abstract [en]

    Protein phosphatase magnesium-dependent 1 delta (PPM1D) terminates cell response to genotoxic stress by negatively regulating the tumor suppressor p53 and other targets at chromatin. Mutations in the exon 6 of the PPM1D result in production of a highly stable, C-terminally truncated PPM1D. These gain-of-function PPM1D mutations are present in various human cancers but their role in tumorigenesis remains unresolved. Here we show that truncated PPM1D impairs activation of the cell cycle checkpoints in human non-transformed RPE cells and allows proliferation in the presence of DNA damage. Next, we developed a mouse model by introducing a truncating mutation in the PPM1D locus and tested contribution of the oncogenic PPM1D(T) allele to colon tumorigenesis. We found that p53 pathway was suppressed in colon stem cells harboring PPM1D(T) resulting in proliferation advantage under genotoxic stress condition. In addition, truncated PPM1D promoted tumor growth in the colon in Apc(min) mice and diminished survival. Moreover, tumor organoids derived from colon of the Apc(min)Ppm1d(T/+) mice were less sensitive to 5-fluorouracil when compared to Apc(min)Ppm1d(+/+)and the sensitivity to 5-fluorouracil was restored by inhibition of PPM1D. Finally, we screened colorectal cancer patients and identified recurrent somatic PPM1D mutations in a fraction of colon adenocarcinomas that are p53 proficient and show defects in mismatch DNA repair. In summary, we provide the first in vivo evidence that truncated PPM1D can promote tumor growth and modulate sensitivity to chemotherapy.

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  • 32.
    Butina, Karen
    et al.
    Karolinska Inst, Sweden; KTH Royal Inst Technol, Sweden; Karolinska Inst, Sweden.
    Tomac, Ana
    Karolinska Inst, Sweden; KTH Royal Inst Technol, Sweden; Karolinska Inst, Sweden.
    Choong, Ferdinand X.
    Karolinska Inst, Sweden; KTH Royal Inst Technol, Sweden; Karolinska Inst, Sweden.
    Shirani, Hamid
    Linköping University, Department of Physics, Chemistry and Biology, Chemistry. Linköping University, Faculty of Science & Engineering.
    Nilsson, Peter
    Linköping University, Department of Physics, Chemistry and Biology, Chemistry. Linköping University, Faculty of Science & Engineering. Karolinska Inst, Sweden; KTH Royal Inst Technol, Sweden.
    Loffler, Susanne
    Karolinska Inst, Sweden; KTH Royal Inst Technol, Sweden; Karolinska Inst, Sweden.
    Richter-Dahlfors, Agneta
    Karolinska Inst, Sweden; KTH Royal Inst Technol, Sweden; Karolinska Inst, Sweden.
    Optotracing for selective fluorescence-based detection, visualization and quantification of liveS. aureusin real-time2020In: npj Biofilms and Microbiomes, E-ISSN 2055-5008, Vol. 6, no 1, article id 35Article in journal (Refereed)
    Abstract [en]

    Methods for bacterial detection are needed to advance the infection research and diagnostics. Based on conformation-sensitive fluorescent tracer molecules, optotracing was recently established for dynamic detection and visualization of structural amyloids and polysaccharides in the biofilm matrix of gram-negative bacteria. Here, we extend the use of optotracing for detection of gram-positive bacteria, focussing on the clinically relevant opportunistic human pathogenStaphylococcus aureus. We identify a donor-acceptor-donor-type optotracer, whose binding-induced fluorescence enables real-time detection, quantification, and visualization ofS. aureusin monoculture and when mixed with gram-negativeSalmonellaEnteritidis. An algorithm-based automated high-throughput screen of 1920S. aureustransposon mutants recognized the cell envelope as the binding target, which was corroborated by super-resolution microscopy of bacterial cells and spectroscopic analysis of purified cell wall components. The binding event was essentially governed by hydrophobic interactions, which permitted custom-designed tuning of the binding selectivity towardsS. aureusversusEnterococcus faecalisby appropriate selection of buffer conditions. Collectively this work demonstrates optotracing as an enabling technology relevant for any field of basic and applied research, where visualization and detection ofS. aureusis needed.

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  • 33.
    Cambra, Josep M.
    et al.
    Univ Murcia, Spain; Inst Biomed Res Murcia IMIB Arrixaca, Spain.
    Martinez, Emilio A.
    Univ Murcia, Spain; Inst Biomed Res Murcia IMIB Arrixaca, Spain.
    Rodriguez-Martinez, Heriberto
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Children's and Women's Health. Linköping University, Faculty of Medicine and Health Sciences.
    Gil, Maria A.
    Univ Murcia, Spain; Inst Biomed Res Murcia IMIB Arrixaca, Spain.
    Cuello, Cristina
    Univ Murcia, Spain; Inst Biomed Res Murcia IMIB Arrixaca, Spain.
    Transcriptional Profiling of Porcine Blastocysts Produced In Vitro in a Chemically Defined Culture Medium2021In: Animals, E-ISSN 2076-2615, Vol. 11, no 5, article id 1414Article in journal (Refereed)
    Abstract [en]

    Simple Summary The development of chemically defined media has become a particularly important task for in vitro embryo production systems, which require maintained reproducible results when new additives are tested for culture, beyond observational studies. Specifically, we need studies measuring the impact of these media on the embryonic transcriptome, particularly those negatively affecting embryo quality. Consequently, this study evaluated by using a microarray approach the transcriptome of porcine embryos produced in vitro, cultured in a defined vs. an undefined medium and contrasted with in vivo-derived embryos. No significantly altered genes were found between in vitro-produced embryos, despite the theoretical limitations that usually accompany defined media. However, when they were compared with in vivo-derived embryos, many altered genes were observed, reflecting how current culture conditions deeply modify the embryonic transcriptome. A better understanding of these alterations may offer new ways to improve in vitro embryo production systems. Likewise, developing a chemically defined medium capable of producing embryos of a similar quality to traditional media may contribute to this task. The development of chemically defined media is a growing trend in in vitro embryo production (IVP). Recently, traditional undefined culture medium with bovine serum albumin (BSA) has been successfully replaced by a chemically defined medium using substances with embryotrophic properties such as platelet factor 4 (PF4). Although the use of this medium sustains IVP, the impact of defined media on the embryonic transcriptome has not been fully elucidated. This study analyzed the transcriptome of porcine IVP blastocysts, cultured in defined (PF4 group) and undefined media (BSA group) by microarrays. In vivo-derived blastocysts (IVV group) were used as a standard of maximum embryo quality. The results showed no differentially expressed genes (DEG) between the PF4 and BSA groups. However, a total of 2780 and 2577 DEGs were detected when comparing the PF4 or the BSA group with the IVV group, respectively. Most of these genes were common in both in vitro groups (2132) and present in some enriched pathways, such as cell cycle, lysosome and/or metabolic pathways. These results show that IVP conditions strongly affect embryo transcriptome and that the defined culture medium with PF4 is a guaranteed replacement for traditional culture with BSA.

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  • 34.
    Cardona Gomez, Maria Eugenia
    et al.
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Molecular Medicine and Virology. Linköping University, Faculty of Medicine and Health Sciences. Karolinska Inst, Sweden.
    Hinkula, Jorma
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Molecular Medicine and Virology. Linköping University, Faculty of Medicine and Health Sciences.
    Gustafsson, Kristin
    Karolinska Inst, Sweden.
    Christensson, Birger
    Karolinska Univ Hosp, Sweden.
    Wahren, Britta
    Karolinska Inst, Sweden.
    Mohamed, Abdalla J.
    Karolinska Inst, Sweden.
    Smith, C. I. Edvard
    Karolinska Inst, Sweden.
    Arteaga, H. Jose
    Karolinska Inst, Sweden; Univ Ind Santander, Colombia.
    Specific properties of shRNA-mediated CCR5 downregulation that enhance the inhibition of HIV-1 infection in combination with shRNA targeting HIV-1 rev2022In: Molecular Biology Reports, ISSN 0301-4851, E-ISSN 1573-4978, Vol. 49, p. 11187-11192Article in journal (Refereed)
    Abstract [en]

    Treatment with RNAi against HIV-1 transcripts efficiently inhibits viral replication but induces selection of escape mutants; therefore, the CCR5 coreceptor was suggested as an additional target. Blocking viral and host transcripts improved the antiviral effect. We have used short hairpin RNA (shRNA) targeting the human CCR5 (shCCR5) or the HIV-1 rev (shRev) transcripts to demonstrate distinctive properties of anti-CCR5 shRNA: shCCR5 induced more sustained protection than shRev; partial reduction in CCR5 expression substantially decreased HIV-1 infection, and shCCR5 performed better than shRev in the mixed shRNA-treated and untreated cultures. These observations indicate that CCR5 inhibitors should be conveniently included in HIV-1 gene silencing treatment schedules when only a certain cell fraction is protected to further reduce endogenous virus in a properly ART-treated HIV-1 infected individual.

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  • 35.
    Carlsson, Uno
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biochemistry. Linköping University, The Institute of Technology.
    Magnusson, Thomas
    Linköping University, Department of Management and Engineering, Project management, Innovations and Entrepreneurship . Linköping University, The Institute of Technology.
    Mårtensson, Lars-Göran
    Linköping University, Department of Physics, Chemistry and Biology, Biochemistry. Linköping University, The Institute of Technology.
    Sunnerhagen, Maria
    Linköping University, Department of Physics, Chemistry and Biology, Biochemistry. Linköping University, The Institute of Technology.
    Svensson, Magdalena
    Linköping University, Department of Physics, Chemistry and Biology, Biochemistry. Linköping University, The Institute of Technology.
    Tibell, Lena
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    To design a novel protein: A CDIO experience in Molecular Biotechnology at Linköping University2006Conference paper (Other academic)
  • 36.
    Carrasco Del Amor, Ana Maria
    et al.
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Cell Biology. Linköping University, Faculty of Medicine and Health Sciences.
    Bautista, Rene Hernandez
    Helmholtz Ctr Munich, Germany.
    Ussar, Siegfried
    Helmholtz Ctr Munich, Germany.
    Cristobal, Susana
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Cell Biology. Linköping University, Faculty of Medicine and Health Sciences. Univ Basque Country UPV EHU, Spain.
    Urbatzka, Ralph
    Univ Porto, Portugal.
    Insights into the mechanism of action of the chlorophyll derivative<i> 13-2-hydroxypheophytine</i> a on reducing neutral lipid reserves in zebrafish larvae and mice adipocytes2023In: European Journal of Pharmacology, ISSN 0014-2999, E-ISSN 1879-0712, Vol. 960, article id 176158Article in journal (Refereed)
    Abstract [en]

    Obesity is a worldwide epidemic and natural products may hold promise in its treatment. The chlorophyll derivative 13-2-hydroxypheophytine (hpa) was isolated in a screen with zebrafish larvae to identify lipid reducing molecules from cyanobacteria. However, the mechanisms underlying the lipid-reducing effects of hpa in zebrafish larvae remain poorly understood. Thus, investigating the mechanism of action of hpa and validation in other model organisms such as mice represents important initial steps.In this study, we identified 14 protein targets of hpa in zebrafish larvae by thermal proteome profiling, and selected two targets (malate dehydrogenase and pyruvate kinase) involved in cellular metabolism for further validation by enzymatic measurements. Our findings revealed a dose-dependent inhibition of pyruvate kinase by hpa exposure using protein extracts of zebrafish larvae in vitro, and in exposure experiments from 3 to 5 days post fertilization in vivo. Analysis of untargeted metabolomics of zebrafish larvae detected 940 mass peaks (66 increased, 129 decreased) and revealed that hpa induced the formation of various phospholipid species (phosphoinositol, phosphoethanolamine, phosphatidic acid). Inter-species validation showed that brown adipocytes exposed to hpa significantly reduced the size of lipid droplets, increased maximal mitochondrial respiratory capacity, and the expression of PPARy during adipocyte differentiation.In line with our data, previous work described that reduced pyruvate kinase activity lowered hepatic lipid content via reduced pyruvate and citrate, and improved mitochondrial function via phospholipids. Thus, our data provide new insights into the molecular mechanism underlying the lipid reducing activities of hpa in zebrafish larvae, and species overlapping functions in reduction of lipids.

  • 37.
    Chamoun, Sherley
    et al.
    Linköping University, Department of Biomedical and Clinical Sciences. Linköping University, Faculty of Medicine and Health Sciences.
    Welander, Jenny
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Inflammation and Infection. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Microbiology.
    Martis, Mihaela-Maria
    Linköping University, Department of Biomedical and Clinical Sciences. Linköping University, Faculty of Medicine and Health Sciences. National Bioinformatics Infrastructure Sweden, Bioinformatics Platform, Science for Life Laboratory, Solna, Sweden.
    Ntzouni, Maria
    Linköping University, Faculty of Medicine and Health Sciences, Core Facility.
    Claesson, Carina
    Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Microbiology. Linköping University, Department of Biomedical and Clinical Sciences, Division of Clinical Chemistry and Pharmacology.
    Vikström, Elena
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Inflammation and Infection. Linköping University, Faculty of Medicine and Health Sciences.
    Turkina, Maria V
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Neurobiology. Linköping University, Faculty of Medicine and Health Sciences.
    Colistin Dependence in Extensively Drug-Resistant Acinetobacter baumannii Strain Is Associated with ISAjo2 and ISAba13 Insertions and Multiple Cellular Responses2021In: International Journal of Molecular Sciences, ISSN 1661-6596, E-ISSN 1422-0067, Vol. 22, no 2, article id 576Article in journal (Refereed)
    Abstract [en]

    The nosocomial opportunistic Gram-negative bacterial pathogen Acinetobacter baumannii is resistant to multiple antimicrobial agents and an emerging global health problem. The polymyxin antibiotic colistin, targeting the negatively charged lipid A component of the lipopolysaccharide on the bacterial cell surface, is often considered as the last-resort treatment, but resistance to colistin is unfortunately increasing worldwide. Notably, colistin-susceptible A. baumannii can also develop a colistin dependence after exposure to this drug in vitro. Colistin dependence might represent a stepping stone to resistance also in vivo. However, the mechanisms are far from clear. To address this issue, we combined proteogenomics, high-resolution microscopy, and lipid profiling to characterize and compare A. baumannii colistin-susceptible clinical isolate (Ab-S) of to its colistin-dependent subpopulation (Ab-D) obtained after subsequent passages in moderate colistin concentrations. Incidentally, in the colistin-dependent subpopulation the lpxA gene was disrupted by insertion of ISAjo2, the lipid A biosynthesis terminated, and Ab-D cells displayed a lipooligosaccharide (LOS)-deficient phenotype. Moreover, both mlaD and pldA genes were perturbed by insertions of ISAjo2 and ISAba13, and LOS-deficient bacteria displayed a capsule with decreased thickness as well as other surface imperfections. The major changes in relative protein abundance levels were detected in type 6 secretion system (T6SS) components, the resistance-nodulation-division (RND)-type efflux pumps, and in proteins involved in maintenance of outer membrane asymmetry. These findings suggest that colistin dependence in A. baumannii involves an ensemble of mechanisms seen in resistance development and accompanied by complex cellular events related to insertional sequences (ISs)-triggered LOS-deficiency. To our knowledge, this is the first study demonstrating the involvement of ISAjo2 and ISAba13 IS elements in the modulation of the lipid A biosynthesis and associated development of dependence on colistin.

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  • 38.
    Cholujová, Dana
    et al.
    Laboratory of Molecular Oncology, Cancer Research Institute, Slovak Academy of Sciences, Vlárska 7, Bratislava, Slovakia.
    Jakubíková, Jana
    Laboratory of Tumor Immunology, Cancer Research Institute, Slovak Academy of Sciences, Vlárska 7, Bratislava, Slovakia.
    Kubeš, Miroslav
    Institute of Virology, Slovak Academy of Sciences, Dubravska cesta 9, Bratislava, Slovakia.
    Arendacká, Barbora
    Institute of Measurement Science, Slovak Academy of Sciences, Dubravska cesta 9, Bratislava, Slovakia.
    Sapák, Michal
    Institute of Immunology, Medical Faculty of Comenius University, Sasinkova 4, Bratislava, Slovakia.
    Ihnatko, Robert
    Institute of Virology, Slovak Academy of Sciences, Dubravska cesta 9, Bratislava, Slovakia.
    Sedlák, Ján
    Laboratory of Tumor Immunology, Cancer Research Institute, Slovak Academy of Sciences, Vlárska 7, Bratislava, Slovakia.
    Comparative study of four fluorescent probes for evaluation of natural killer cell cytotoxicity assays2008In: Immunobiology, ISSN 0171-2985, E-ISSN 1878-3279, Vol. 213, no 8, p. 629-640Article in journal (Refereed)
    Abstract [en]

    Cytotoxicity is one of the major defence mechanisms against both virus-infected and tumor cells. Radioactive 51chromium (51Cr) release assay is a “gold standard” for assessment of natural killer (NK) cytolytic activity in vitro. Several disadvantages of this assay led us to design alternative tools based on flow cytometry analysis. Four different fluorescent dyes, calcein acetoxymethyl ester (CAM), carboxyfluorescein succinimidyl ester (CFSE), Vybrant DiO (DiO) and MitoTracker Green (MTG) were tested for labeling of NK target K-562 cells. Target staining stability, spontaneous release of fluorochromes and subsequent accumulation in bystander unstained cells were measured using fluorimetry and flow cytometry. Healthy donor peripheral blood mononuclear cells and affinity column purified NK cells were used as effectors coincubated with target K-562 cells at different E:T ratios for 3h and 90min, respectively. Fluorescent probe 7-amino-actinomycin D was used for live and dead cell discrimination. Bland–Altman statistical method was applied to measure true agreement for all CAM–51Cr, CFSE–51Cr, DiO–51Cr and MTG–51Cr pairs analyzed. Based on the data, none of the four proposed methods can be stated equivalent to the standard 51Cr release assay. Considering linear relationships between data obtained with four fluorochromes and 51Cr release assay as well as linear regression analysis with R2=0.9393 value for CAM–51Cr pair, we found the CAM assay to be the most closely related to the 51Cr assay.

  • 39.
    Choong, Ferdinand
    et al.
    Karolinska Institutet, Stockholm, Sweden.
    Bäck, Marcus
    Linköping University, Department of Physics, Chemistry and Biology, Chemistry. Linköping University, Faculty of Science & Engineering.
    Fahlen, Sara
    Karolinska Institutet, Stockholm, Sweden.
    Johansson, Leif B. G.
    Linköping University, Department of Physics, Chemistry and Biology, Chemistry. Linköping University, Faculty of Science & Engineering.
    Melican, Keira
    Karolinska Institutet, Stockholm, Sweden.
    Rhen, Mikael
    Karolinska Institutet, Stockholm, Sweden.
    Nilsson, Peter
    Linköping University, Department of Physics, Chemistry and Biology, Chemistry. Linköping University, Faculty of Science & Engineering.
    Richter-Dahlfors, Agneta
    Karolinska Institutet, Stockholm, Sweden.
    Real-time opto-tracing of curli and cellulose in live Salmonella biofilms using conjugated oligothiophenes2016In: npj Biofilms and Microbiomes, E-ISSN 2055-5008, Vol. 2, article id 16024Article in journal (Refereed)
    Abstract [en]

    Extracellular matrix (ECM) is the protein- and polysaccharide-rich backbone of bacterial biofilms that provides a defensive barrier in clinical, environmental and industrial settings. Understanding the dynamics of biofilm formation in native environments has been hindered by a lack of research tools. Here we report a method for simultaneous, real-time, in situ detection and differentiation of the Salmonella ECM components curli and cellulose, using non-toxic, luminescent conjugated oligothiophenes (LCOs). These flexible conjugated polymers emit a conformation-dependent fluorescence spectrum, which we use to kinetically define extracellular appearance of curli fibres and cellulose polysaccharides during bacterial growth. The scope of this technique is demonstrated by defining biofilm morphotypes of Salmonella enterica serovars Enteritidis and Typhimurium, and their isogenic mutants in liquid culture and on solid media, and by visualising the ECM components in native biofilms. Our reported use of LCOs across a number of platforms, including intracellular cellulose production in eukaryotic cells and in infected tissues, demonstrates the versatility of this optotracing technology, and its ability to redefine biofilm research.

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  • 40.
    Christoffersson, Jonas
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biotechnology. Linköping University, Faculty of Science & Engineering.
    Aronsson, Christopher
    Linköping University, Department of Physics, Chemistry and Biology, Molecular Physics. Linköping University, Faculty of Science & Engineering.
    Jury, Michael
    Linköping University, Department of Physics, Chemistry and Biology, Molecular Physics. Linköping University, Faculty of Science & Engineering.
    Selegård, Robert
    Linköping University, Department of Physics, Chemistry and Biology, Molecular Physics. Linköping University, Faculty of Science & Engineering.
    Aili, Daniel
    Linköping University, Department of Physics, Chemistry and Biology, Molecular Physics. Linköping University, Faculty of Science & Engineering.
    Mandenius, Carl-Fredrik
    Linköping University, Department of Physics, Chemistry and Biology, Biotechnology. Linköping University, Faculty of Science & Engineering.
    Fabrication of modular hyaluronan-PEG hydrogels to support 3D cultures of hepatocytes in a perfused liver-on-a-chip device2019In: Biofabrication, ISSN 1758-5082, E-ISSN 1758-5090, Vol. 11, no 1, p. 1-13, article id 015013Article in journal (Refereed)
    Abstract [en]

    Liver cell culture models are attractive in both tissue engineering and for development of assays for drug toxicology research. To retain liver specific cell functions, the use of adequate cell types and culture conditions, such as a 3D orientation of the cells and a proper supply of nutrients and oxygen, are critical. In this article, we show how extracellular matrix mimetic hydrogels can support hepatocyte viability and functionality in a perfused liver-on-a-chip device. A modular hydrogel system based on hyaluronan and poly(ethylene glycol) (HA-PEG), modified with cyclooctyne moieties for bioorthogonal strain-promoted alkyne-azide 1, 3-dipolar cycloaddition (SPAAC), was developed, characterized, and compared for cell compatibility to hydrogels based on agarose and alginate. Hepatoma cells (HepG2) formed spheroids with viable cells in all hydrogels with the highest expression of albumin and urea in alginate hydrogels. By including an excess of cyclooctyne in the HA backbone, azide-modified cell adhesion motifs (linear and cyclic RGD peptides) could be introduced in order to enhance viability and functionality of human induced pluripotent stem cell derived hepatocytes (hiPS-HEPs). In the HA-PEG hydrogels modified with cyclic RGD peptides hiPS-HEPs migrated and grew in 3D and showed an increased viability and higher albumin production compared to when cultured in the other hydrogels. This flexible SPAAC crosslinked hydrogel system enabled fabrication of perfused 3D cell culture of hiPS-HEPs and is a promising material for further development and optimization of liver-on-a-chip devices.

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    Fabrication of modular hyaluronan-PEG hydrogels to support 3D cultures of hepatocytes in a perfused liver-on-a-chip device
  • 41.
    Christoffersson, Jonas
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biotechnology. Linköping University, Faculty of Science & Engineering.
    Meier, Florian
    Boehringer Ingelheim Pharma GmbH and Co. KG, Nonclinical Drug Safety Germany, D-88397 Biberach an der Riss, Germany.
    Kempf, Henning
    Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.
    Schwanke, Kristin
    Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.
    Coffee, Michelle
    Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.
    Beilmann, Mario
    Boehringer Ingelheim Pharma GmbH and Co. KG, Nonclinical Drug Safety Germany, D-88397 Biberach an der Riss, Germany.
    Zweigerdt, Robert
    Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.
    Mandenius, Carl-Fredrik
    Linköping University, Department of Physics, Chemistry and Biology, Biotechnology. Linköping University, Faculty of Science & Engineering.
    A Cardiac Cell Outgrowth Assay for Evaluating Drug Compounds Using a Cardiac Spheroid-on-a-Chip Device2018In: Bioengineering, E-ISSN 2306-5354, Vol. 5, no 2, p. 1-13, article id 36Article in journal (Refereed)
    Abstract [en]

    Three-dimensional (3D) models with cells arranged in clusters or spheroids have emerged as valuable tools to improve physiological relevance in drug screening. One of the challenges with cells cultured in 3D, especially for high-throughput applications, is to quickly and non-invasively assess the cellular state in vitro. In this article, we show that the number of cells growing out from human induced pluripotent stem cell (hiPSC)-derived cardiac spheroids can be quantified to serve as an indicator of a drug&rsquo;s effect on spheroids captured in a microfluidic device. Combining this spheroid-on-a-chip with confocal high content imaging reveals easily accessible, quantitative outgrowth data. We found that effects on outgrowing cell numbers correlate to the concentrations of relevant pharmacological compounds and could thus serve as a practical readout to monitor drug effects. Here, we demonstrate the potential of this semi-high-throughput &ldquo;cardiac cell outgrowth assay&rdquo; with six compounds at three concentrations applied to spheroids for 48 h. The image-based readout complements end-point assays or may be used as a non-invasive assay for quality control during long-term culture.

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  • 42. Order onlineBuy this publication >>
    Cros, Olivier
    Linköping University, Department of Biomedical Engineering. Linköping University, Faculty of Science & Engineering.
    Structural properties of the mastoid using image analysis and visualization2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The mastoid, located in the temporal bone, houses an air cell system whose cells have a variation in size that can go far below current conventional clinical CT scanner resolution. Therefore, the mastoid air cell system is only partially represented in a CT scan. Where the conventional clinical CT scanner lacks level of minute details, micro-CT scanning provides an overwhelming amount of ne details. The temporal bone being one of the most complex in the human body, visualization of micro-CT scanning of this boneawakens the curiosity of the experimenter, especially with the correct visualization settings.

    This thesis first presents a statistical analysis determining the surface area to volume ratio of the mastoid air cell system of human temporal bone, from micro-CT scanning using methods previously applied for conventional clinical CT scans. The study compared current results with previous studies, with successive downsampling the data down to a resolution found in conventional clinical CT scanning. The results from the statistical analysis showed that all the small mastoid air cells, that cannot be detected in conventional clinical CT scans, do heavily contribute to the estimation of the surface area, and in consequence to the estimation of the surface area to volume ratio by a factor of about 2.6. Such a result further strengthens the idea of the mastoid to play an active role in pressure regulation and gas exchange.

    Discovery of micro-channels through specific use of a non-traditional transfer function was then reported, where a qualitative and a quantitative pre-analysis were performed and reported. To gain more knowledge about these micro-channels, a local structure tensor analysis was applied where structures are described in terms of planar, tubular, or isotropic structures. The results from this structural tensor analysis suggest these microchannels to potentially be part of a more complex framework, which hypothetically would provide a separate blood supply for the mucosa lining the mastoid air cell system.

    The knowledge gained from analysing the micro-channels as locally providing blood to the mucosa, led to the consideration of how inflammation of the mucosa could impact the pneumatization of the mastoid air cell system. Though very primitive, a 3D shape analysis of the mastoid air cell system was carried out. The mastoid air cell system was first represented in a compact form through a medial axis, from which medial balls could be used. The medial balls, representative of how large the mastoid air cells can be locally, were used in two complementary clustering methods, one based on the size diameter of the medial balls and one based on their location within the mastoid air cell system. From both quantitative and qualitative statistics, it was possible to map the clusters based on pre-defined regions already described in the literature, which opened the door for new hypotheses concerning the effect of mucosal inflammation on the mastoid pneumatization.

    Last but not least, discovery of other structures, previously unreported in the literature, were also visually observed and briefly discussed in this thesis. Further analysis of these unknown structures is needed.

    List of papers
    1. Determination of the mastoid surface area and volume based on micro-CT scanning of human temporal bone: Geometrical parameters dependence on scanning resolutions
    Open this publication in new window or tab >>Determination of the mastoid surface area and volume based on micro-CT scanning of human temporal bone: Geometrical parameters dependence on scanning resolutions
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    2016 (English)In: Hearing Research, ISSN 0378-5955, E-ISSN 1878-5891, Vol. 340, p. 127-134Article in journal (Refereed) Published
    Abstract [en]

    The mastoid air cell system (MACS) with its large complex of interconnected air cells reflects an enhanced surface area (SA) relative to its volume (V), which may indicate that the MACS is adapted to gas exchange and has a potential role in middle ear pressure regulation. Thus, these geometric parameters of the MACS have been studied by high resolution clinical CT scanning. However, the resolution of these scans is limited to a voxel size of around 0.6 mm in all dimensions, and so, the geometrical parameters are also limited. Small air cells may appear below the resolution and cannot be detected. Such air cells may contribute to a much higher SA than the V, and thus, also the SA/V ratio. More accurate parameters are important for analysis of the function of the MACS including physiological modeling.

    Our aim was to determine the SA, V, and SA/V ratio in MACS in human temporal bones at highest resolution by using micro-CT-scanning. Further, the influence of the resolution on these parameters was investigated by downsampling the data. Eight normally aerated temporal bones were scanned at the highest possible resolution (30-60 μm). The SA was determined using a triangular mesh fitted onto the segmented MACS. The V was determined by summing all the voxels containing air. Downsampling of the original data was applied four times by a factor of 2.

    The mean SA was 194 cm2, the mean V was 9 cm3, and the mean SA/V amounted to 22 cm-1. Decreasing the resolution resulted in a non-linear decrement of SA and SA/V, whereas V was mainly independent of the resolution.

    The current study found significantly higher SA and SA/V compared with previous studies using clinical CT scanning at lower resolutions. These findings indicate a separate role of the MACS compared with the tympanum, and the results are important for a more accurate modeling of the middle ear physiology.

    Keywords
    Mastoid air cells; medical imaging; micro-CT; surface area; volume
    National Category
    Radiology, Nuclear Medicine and Medical Imaging
    Identifiers
    urn:nbn:se:liu:diva-122176 (URN)10.1016/j.heares.2015.12.005 (DOI)000386417900016 ()
    Available from: 2015-10-23 Created: 2015-10-23 Last updated: 2019-12-02Bibliographically approved
    2. Micro-channels in the mastoid anatomy. Indications of a separate blood supply of the air cell system mucosa by micro-CT scanning
    Open this publication in new window or tab >>Micro-channels in the mastoid anatomy. Indications of a separate blood supply of the air cell system mucosa by micro-CT scanning
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    2013 (English)In: Hearing Research, ISSN 0378-5955, E-ISSN 1878-5891, Vol. 301, p. 60-65Article in journal (Refereed) Published
    Abstract [en]

    The mastoid air cell system has traditionally been considered to have a passive role in gas exchange and pressure regulation of the middle ear possibly with some acoustic function. However, more evidence has focused on the mucosa of the mastoid, which may play a more active role in regulation of middle ear pressure.

    In this study we have applied micro-CT scanning on a series of three human temporal bones. This approach greatly enhances the resolution (40–60 μm), so that we have discovered anatomical details, which has not been reported earlier. Thus, qualitative analysis using volume rendering has demonstrated notable micro-channels connecting the surface of the compact bone directly to the mastoid air cells as well as forming a network of connections between the air cells. Quantitative analysis on 2D slices was employed to determine the average diameter of these micro-channels (158 μm; range = 40–440 μm) as well as their density at a localized area (average = 75 cm−2; range = 64–97 cm−2).

    These channels are hypothesized to contain a separate vascular supply for the mastoid mucosa. However, future studies of the histological structure of the micro-channels are warranted to confirm the hypothesis. Studies on the mastoid mucosa and its blood supply may improve our knowledge of its physiological properties, which may have important implications for our understanding of the pressure regulation of the middle ear.

    Place, publisher, year, edition, pages
    Elsevier, 2013
    Keywords
    mastoid, micro CT, middle ear
    National Category
    Otorhinolaryngology Radiology, Nuclear Medicine and Medical Imaging Medical Image Processing
    Identifiers
    urn:nbn:se:liu:diva-92813 (URN)10.1016/j.heares.2013.03.002 (DOI)000320478100009 ()23518400 (PubMedID)
    Available from: 2013-05-22 Created: 2013-05-22 Last updated: 2017-12-06Bibliographically approved
    3. Structural Analysis of Micro-channels in Human Temporal Bone
    Open this publication in new window or tab >>Structural Analysis of Micro-channels in Human Temporal Bone
    2015 (English)In: IEEE 12th International Symposium on Biomedical Imaging (ISBI), 2015 IEEE 12th International Symposium on, Institute of Electrical and Electronics Engineers (IEEE), 2015, p. 9-12Conference paper, Published paper (Refereed)
    Abstract [en]

    Recently, numerous micro-channels have been discovered in the human temporal bone by micro-CT-scanning. Preliminary structure of these channels has suggested they contain a new separate blood supply for the mucosa of the mastoid air cells, which may have important functional implications. This paper proposes a structural analysis of the microchannels to corroborate this role. A local structure tensor is first estimated. The eigenvalues obtained from the estimated local structure tensor were then used to build probability maps representing planar, tubular, and isotropic tensor types. Each tensor type was assigned a respective RGB color and the full structure tensor was rendered along with the original data. Such structural analysis provides new and relevant information about the micro-channels but also their connections to mastoid air cells. Before carrying a future statistical analysis, a more accurate representation of the micro-channels in terms of local structure tensor analysis using adaptive filtering is needed.

    Place, publisher, year, edition, pages
    Institute of Electrical and Electronics Engineers (IEEE), 2015
    Series
    IEEE International Symposium on Biomedical Imaging, ISSN 1945-7928
    Keywords
    Human temporal bone, mastoid, microchannels, quadrature filters, structure tensor, visualization
    National Category
    Radiology, Nuclear Medicine and Medical Imaging
    Identifiers
    urn:nbn:se:liu:diva-122177 (URN)10.1109/ISBI.2015.7163804 (DOI)000380546000003 ()978-1-4799-2374-8 (ISBN)
    Conference
    IEEE 12th International Symposium on Biomedical Imaging (ISBI), 2015 IEEE 12th International Symposium on, 16-19 April, New York, USA
    Available from: 2015-10-23 Created: 2015-10-23 Last updated: 2017-05-10Bibliographically approved
    4. Enhancement of micro-channels within the human mastoid bone based on local structure tensor analysis
    Open this publication in new window or tab >>Enhancement of micro-channels within the human mastoid bone based on local structure tensor analysis
    2016 (English)In: Image Proceessing Theory, Tools and Apllications, IEEE, 2016Conference paper, Published paper (Refereed)
    Abstract [en]

    Numerous micro-channels have recently been discovered in the human temporal bone by x-ray micro-CT-scanning. After a preliminary study suggesting that these micro-channels form a separate blood supply for the mucosa of the mastoid air cells, a structural analysis of the micro-channels using a local structure tensor was carried out. Despite the high-resolution of the micro-CT scan, presence of noise within the air cells along with missing information in some micro-channels suggested the need of image enhancement. This paper proposes an adaptive enhancement of the micro-channels based on a local structure analysis while minimizing the impact of noise on the overall data. Comparison with an anisotropic diffusion PDE based scheme was also performed.

    Place, publisher, year, edition, pages
    IEEE, 2016
    Series
    International Conference on Image Processing Theory Tools and Applications (IPTA), E-ISSN 2154-512X
    Keywords
    Micro-channels, Structure tensor analysis, Image enhancement, Adaptive filtering, Human temporal bone, Mastoid bone
    National Category
    Medical Engineering
    Identifiers
    urn:nbn:se:liu:diva-134434 (URN)10.1109/IPTA.2016.7821019 (DOI)000393589800071 ()9781467389105 (ISBN)9781467389112 (ISBN)
    Conference
    6th International Conference on Image Processing Theory Tools and Applications (IPTA), Oulu, Finland, 12-15 December 2016
    Note

    Funding agencies: Obel Family Foundation (Denmark)

    Available from: 2017-02-13 Created: 2017-02-13 Last updated: 2017-06-21
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  • 43.
    Dassie, Justin P.
    et al.
    Department of Internal Medicine, University of of Iowa, 375 Newton Rd, 5202 MERF, Iowa City, IA, United States.
    Hernandez, Luiza I.
    Department of Internal Medicine, University of of Iowa, 375 Newton Rd, 5202 MERF, Iowa City, IA, United States.
    Thomas, Gregory S.
    Department of Internal Medicine, University of of Iowa, 375 Newton Rd, 5202 MERF, Iowa City, IA, United States.
    Long, Matthew E.
    Molecular and Cellular Biology Program, University of of Iowa, Iowa City, IA, United States; Inflammation Program, University of of Iowa, Iowa City, IA, United States.
    Rockey, William M.
    Department of Radiation Oncology, University of of Iowa, Iowa City, IA, United States.
    Howell, Craig A.
    Department of Internal Medicine, University of of Iowa, 375 Newton Rd, 5202 MERF, Iowa City, IA, United States.
    Chen, Yani
    Department of Internal Medicine, University of of Iowa, 375 Newton Rd, 5202 MERF, Iowa City, IA, United States.
    Hernandez, Frank J
    Department of Internal Medicine, University of of Iowa, 375 Newton Rd, 5202 MERF, Iowa City, IA, United States.
    Liu, Xiu Y.
    Department of Internal Medicine, University of of Iowa, 375 Newton Rd, 5202 MERF, Iowa City, IA, United States.
    Wilson, Mary E.
    Department of Internal Medicine, University of of Iowa, 375 Newton Rd, 5202 MERF, Iowa City, IA, United States; Department of Microbiology, University of of Iowa, Iowa City, IA, United States; Veterans Affairs Medical Center, University of of Iowa, Iowa City, IA, United States.
    Allen, Lee-Ann
    Department of Internal Medicine, University of of Iowa, 375 Newton Rd, 5202 MERF, Iowa City, IA, United States; Molecular and Cellular Biology Program, University of of Iowa, Iowa City, IA, United States; Inflammation Program, University of of Iowa, Iowa City, IA, United States; Department of Microbiology, University of of Iowa, Iowa City, IA, United States; Veterans Affairs Medical Center, University of of Iowa, Iowa City, IA, United States.
    Vaena, Daniel A.
    Department of Internal Medicine, University of of Iowa, 375 Newton Rd, 5202 MERF, Iowa City, IA, United States.
    Meyerholz, David K.
    Department of Pathology, University of of Iowa, Iowa City, IA, United States.
    Giangrande, Paloma H.
    Department of Internal Medicine, University of of Iowa, 375 Newton Rd, 5202 MERF, Iowa City, IA, United States; Molecular and Cellular Biology Program, University of of Iowa, Iowa City, IA, United States; Department of Radiation Oncology, University of of Iowa, Iowa City, IA, United States.
    Targeted inhibition of prostate cancer metastases with an RNA aptamer to prostate-specific membrane antigen2014In: Molecular Therapy, ISSN 1525-0016, E-ISSN 1525-0024, Vol. 22, no 11, p. 1910-1922Article in journal (Refereed)
    Abstract [en]

    Cell-targeted therapies (smart drugs), which selectively control cancer cell progression with limited toxicity to normal cells, have been developed to effectively treat some cancers. However, many cancers such as metastatic prostate cancer (PC) have yet to be treated with current smart drug technology. Here, we describe the thorough preclinical characterization of an RNA aptamer (A9g) that functions as a smart drug for PC by inhibiting the enzymatic activity of prostate-specific membrane antigen (PSMA). Treatment of PC cells with A9g results in reduced cell migration/invasion in culture and metastatic disease in vivo. Importantly, A9g is safe in vivo and is not immunogenic in human cells. Pharmacokinetic and biodistribution studies in mice confirm target specificity and absence of non-specific on/off-target effects. In conclusion, these studies provide new and important insights into the role of PSMA in driving carcinogenesis and demonstrate critical endpoints for the translation of a novel RNA smart drug for advanced stage PC. © The American Society of Gene amp; Cell Therapy.

  • 44.
    Diczfalusy, Elin
    et al.
    Linköping University, Department of Physics, Chemistry and Biology.
    Broberg, Sarah
    Linköping University, Department of Physics, Chemistry and Biology.
    Non-Invasive Methods for Detecting Drug and Alcohol Impaired Drivers: - a Study of Alcohol and Drug Biomarkers and Optical Detection Techniques2009Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In recent years, the use of alcohol and psychoactive drugs in combination withdriving has recieved increased attention. The lack of in-vehicle devices capable ofdetecting recent drug consumption and the difficulties associated with the breathbasedalcolocks in use today makes it interesting to investigate methods that areable to non-invasivelly measure analytes directly in the blood.

    The assignment of this project, commissioned by Volvo Technology Corporationand Volvo Car Corporation, is to map substances that constitute a possible threatto traffic safety, identify suitable detection markers as a proof of administrationof these substances, and study possible non-invasive techniques to detect thesemarkers. The objective is to present for Volvo if and how to continue evaluatingand developing a non-invasive detection device.

    The project has been carried out by performing an extensive literature study and averification experiment. From the literature review, a number of substances affectingdriving performance could be identified, and a metabolic study was performedfor each drug to map suitable biomarkers. Furthermore, two potential techniquesfor non-invasive detection, near-infrared Raman spectroscopy and near-infraredspectroscopy, were found and evaluated. The experiment was conducted usingnear-infrared Raman spectroscopy, with the aim of investigating the sensitivityand linearity of the method for ethanol detection.

    Based on the theoretical evaluation, both near-infrared Raman spectroscopy andnear-infrared spectroscopy are expected to have potential for non-invasive detectionof ethanol. The experiment further proved the theoretical conclusionsmade for near-infrared Raman spectroscopy. However, neither of the techniquesis thought to have potential for drug detection.Altogether, we believe that non-invasive ethanol detection is possible, but suggestfurther experiments in order to determine which technique to be preferred.

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  • 45.
    Dong, Yibing
    et al.
    Nanyang Technol Univ, Singapore.
    Suryani, Luvita
    Nanyang Technol Univ, Singapore.
    Zhou, Xinran
    Nanyang Technol Univ, Singapore.
    Muthukumaran, Padmalosini
    Nanyang Technol Univ, Singapore.
    Rakshit, Moumita
    Nanyang Technol Univ, Singapore.
    Yang, Fengrui
    Nanyang Technol Univ, Singapore.
    Wen, Feng
    Nanyang Technol Univ, Singapore.
    Hassanbhai, Ammar Mansoor
    Nanyang Technol Univ, Singapore.
    Parida, Kaushik
    Nanyang Technol Univ, Singapore.
    Simon, Daniel
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Iandolo, Donata
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering. Mines-Saint-Étienne, Campus Santé Innovations, 10 rue de la Marandière, Saint-Priest-en-Jarez, France.
    Lee, Pooi See
    Nanyang Technol Univ, Singapore.
    Ng, Kee Woei
    Nanyang Technol Univ, Singapore; Harvard Univ, MA 02115 USA; Nanyang Technol Univ, Singapore.
    Teoh, Swee Hin
    Nanyang Technol Univ, Singapore; Nanyang Technol Univ, Singapore.
    Synergistic Effect of PVDF-Coated PCL-TCP Scaffolds and Pulsed Electromagnetic Field on Osteogenesis2021In: International Journal of Molecular Sciences, ISSN 1661-6596, E-ISSN 1422-0067, Vol. 22, no 12, article id 6438Article in journal (Refereed)
    Abstract [en]

    Bone exhibits piezoelectric properties. Thus, electrical stimulations such as pulsed electromagnetic fields (PEMFs) and stimuli-responsive piezoelectric properties of scaffolds have been investigated separately to evaluate their efficacy in supporting osteogenesis. However, current understanding of cells responding under the combined influence of PEMF and piezoelectric properties in scaffolds is still lacking. Therefore, in this study, we fabricated piezoelectric scaffolds by functionalization of polycaprolactone-tricalcium phosphate (PCL-TCP) films with a polyvinylidene fluoride (PVDF) coating that is self-polarized by a modified breath-figure technique. The osteoinductive properties of these PVDF-coated PCL-TCP films on MC3T3-E1 cells were studied under the stimulation of PEMF. Piezoelectric and ferroelectric characterization demonstrated that scaffolds with piezoelectric coefficient d(33) = -1.2 pC/N were obtained at a powder dissolution temperature of 100 degrees C and coating relative humidity (RH) of 56%. DNA quantification showed that cell proliferation was significantly enhanced by PEMF as low as 0.6 mT and 50 Hz. Hydroxyapatite staining showed that cell mineralization was significantly enhanced by incorporation of PVDF coating. Gene expression study showed that the combination of PEMF and PVDF coating promoted late osteogenic gene expression marker most significantly. Collectively, our results suggest that the synergistic effects of PEMF and piezoelectric scaffolds on osteogenesis provide a promising alternative strategy for electrically augmented osteoinduction. The piezoelectric response of PVDF by PEMF, which could provide mechanical strain, is particularly interesting as it could deliver local mechanical stimulation to osteogenic cells using PEMF.

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  • 46.
    Doumpas, Nikolaos
    et al.
    Univ Zurich, Switzerland.
    Söderholm, Simon
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Molecular Medicine and Virology. Linköping University, Faculty of Medicine and Health Sciences.
    Narula, Smarth
    McMaster Univ, Canada.
    Moreira, Steven
    McMaster Univ, Canada.
    Doble, Bradley W.
    McMaster Univ, Canada; Univ Manitoba, Canada; Univ Manitoba, Canada.
    Cantù, Claudio
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Molecular Medicine and Virology. Linköping University, Faculty of Medicine and Health Sciences.
    Basler, Konrad
    Univ Zurich, Switzerland.
    TCF/LEF regulation of the topologically associated domain ADI promotes mESCs to exit the pluripotent ground state2021In: Cell Reports, E-ISSN 2211-1247, Vol. 36, no 11, article id 109705Article in journal (Refereed)
    Abstract [en]

    Mouse embryonic stem cells (mESCs) can bemaintained in vitro in defined N2B27 medium supplemented with two chemical inhibitors for GSK3 and MEK (2i) and the cytokine leukemia inhibitory factor (LIF), which act synergistically to promote self-renewal and pluripotency. Here, we find that genetic deletion of the four genes encoding the TCF/LEF transcription factors confersm ESCs with the ability to self-renew in N2B27 medium alone. TCF/LEF quadruple knockout (qKO) mESCs display dysregulation of several genes, including Aire, Dnmt3l, and IcosL, located adjacent to each other within a topologically associated domain (TAD). Aire, Dnmt3l, and IcosL appear to be regulated by TCF/LEF in a beta-catenin independent manner. Moreover, downregulation of Aire and Dnmt3l in wild-type mESCs mimics the loss of TCF/LEF and increases mESC survival in the absence of 2iL. Hence, this study identifies TCF/LEF effectors that mediate exit from the pluripotent state.

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  • 47.
    Duran Rosich, David
    et al.
    ViRVIG Group, UPC Barcelona, Barcelona, Spain.
    Hermosilla, Pedro
    Visual Computing Group, U. Ulm, Ulm, Germany.
    Ropinski, Timo
    Visual Computing Group, U. Ulm, Ulm, Germany.
    Kozlikova, Barbora
    Masaryk University, Brno, Czech Republic.
    Vinacua, Àlvar
    ViRVIG Group, UPC Barcelona, Barcelona, Spain.
    Vazquez, Pere-Pau
    ViRVIG Group, UPC Barcelona, Barcelona, Spain.
    Visualization of Large Molecular Trajectories2018In: IEEE Transactions on Visualization and Computer Graphics, ISSN 1077-2626, E-ISSN 1941-0506Article in journal (Refereed)
    Abstract [en]

    The analysis of protein-ligand interactions is a time-intensive task. Researchers have to analyze multiple physico-chemical properties of the protein at once and combine them to derive conclusions about the protein-ligand interplay. Typically, several charts are inspected, and 3D animations can be played side-by-side to obtain a deeper understanding of the data. With the advances in simulation techniques, larger and larger datasets are available, with up to hundreds of thousands of steps. Unfortunately, such large trajectories are very difficult to investigate with traditional approaches. Therefore, the need for special tools that facilitate inspection of these large trajectories becomes substantial. In this paper, we present a novel system for visual exploration of very large trajectories in an interactive and user-friendly way. Several visualization motifs are automatically derived from the data to give the user the information about interactions between protein and ligand. Our system offers specialized widgets to ease and accelerate data inspection and navigation to interesting parts of the simulation. The system is suitable also for simulations where multiple ligands are involved. We have tested the usefulness of our tool on a set of datasets obtained from protein engineers, and we describe the expert feedback.

  • 48.
    El-Serafi, Ahmed T.
    et al.
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Hand and Plastic Surgery.
    El-Serafi, Ibrahim
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Hand and Plastic Surgery. Ajman Univ, U Arab Emirates.
    Steinvall, Ingrid
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Hand and Plastic Surgery.
    Sjöberg, Folke
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Hand and Plastic Surgery.
    Elmasry, Moustafa
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Hand and Plastic Surgery.
    A Systematic Review of Keratinocyte Secretions: A Regenerative Perspective2022In: International Journal of Molecular Sciences, ISSN 1661-6596, E-ISSN 1422-0067, Vol. 23, no 14, article id 7934Article, review/survey (Refereed)
    Abstract [en]

    Cell regenerative therapy is a modern solution for difficult-to-heal wounds. Keratinocytes, the most common cell type in the skin, are difficult to obtain without the creation of another wound. Stem cell differentiation towards keratinocytes is a challenging process, and it is difficult to reproduce in chemically defined media. Nevertheless, a co-culture of keratinocytes with stem cells usually achieves efficient differentiation. This systematic review aims to identify the secretions of normal human keratinocytes reported in the literature and correlate them with the differentiation process. An online search revealed 338 references, of which 100 met the selection criteria. A total of 80 different keratinocyte secretions were reported, which can be grouped mainly into cytokines, growth factors, and antimicrobial peptides. The growth-factor group mostly affects stem cell differentiation into keratinocytes, especially epidermal growth factor and members of the transforming growth factor family. Nevertheless, the reported secretions reflected the nature of the involved studies, as most of them focused on keratinocyte interaction with inflammation. This review highlights the secretory function of keratinocytes, as well as the need for intense investigation to characterize these secretions and evaluate their regenerative capacities.

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  • 49.
    Elserafy, Ahmed Taher
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences.
    Stem Cells, From A to B [Arabic]2024Book (Other (popular science, discussion, etc.))
    Abstract [en]

    Have you ever thought about how our body compensates for lost cells? Have you heard about a new management line for several diseases using so-called stem cells? You may have heard about some pa<ents being defrauded with claims of stem cell therapy. 

    When these magical cells and their therapeutic ability were discovered, many researchers and doctors believed that we found a cure for cureless conditions. Stem cells have amazing abilities to differentiate into various cells of the body, which is an indisputable fact, replacing damaged tissues in a manner similar to human spare parts. Thus, a new branch of medicine known as regenerative medicine has been emerged. The challenge is to harness these cells to respond adequately to the differentiation triggers. Also, the development of the protocols to introduce these cells into the body is a complex process. The mistake that a few medicals made was to rush the use of stem cells before establishing the conditions for treatment, including laboratory experiments and studies on experimental animals and groups of patients. These validations are required for licensing these cells as a medical treatment.

    This book aims at providing basic information about stem cells and regenerative medicine from their scientific sources. In addition, the book highlights the current clinical studies, as well as future trends in this field.

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  • 50.
    Erdtman, Edvin
    et al.
    Institutionen för naturvetenskap and Modelling and Simulation Research Center, Örebro University, Sweden.
    dos Santos, Daniel J. V. A.
    i. Med. UL/Institute for Medicine and Pharmaceutical Sciences, Faculty of Pharmacy, University of Lisbon. Av. Prof. Gama Pinto, Lisbon, Portugal.
    Löfgren, Lennart
    Head- and Neck Oncology Center, Örebro University Hospital, Örebro, Sweden.
    Eriksson, Leif A.
    Örebro universitet, Institutionen för naturvetenskap.
    Modelling the behavior of 5-aminolevulinic acid and its alkyl esters in a lipid bilayer2008In: Chemical Physics Letters, ISSN 0009-2614, E-ISSN 1873-4448, Vol. 463, no 1-3, p. 178-182Article in journal (Refereed)
    Abstract [en]

    5-Aminolevulinic acid (5ALA) and ester derivates thereof are used as prodrugs in photodynamic therapy (PDT). The behavior of 5ALA and three esters of 5ALA in a DPPC lipid bilayer is investigated. In particular, the methyl ester displays a very different free energy profile, where the highest barrier is located in the region with highest lipid density, while the others have their peak in the middle of the membrane, and also displays a considerably lower permeability coefficient than neutral 5ALA and the ethyl ester. The zwitterion of 5ALA has the highest permeability constant, but a significant free energy minimum in the polar head-group region renders an accumulation in this region.

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