The specific granule glycoprotein olfactomedin-4 (Olfm4) marks a subset (1-70%) of human neutrophils and the Olfm4-high (Olfm4-H) proportion has been found to correlate with septic shock severity. The aim of this study was to decipher proteomic differences between the subsets in healthy individuals, hypothesizing that Olfm4-H neutrophils have a proteomic profile distinct from that of Olfm4 low (Olfm4-L) neutrophils. We then extended the investigation to septic shock. A novel protocol for the preparation of fixed, antibody-stained, and sorted neutrophils for LC-MS/MS was developed. In healthy individuals, 39 proteins showed increased abundance in Olfm4-H, including the small GTPases Rab3d and Rab11a. In Olfm4-L, 52 proteins including neutrophil defensin alpha 4, CXCR1, Rab3a, and S100-A7 were more abundant. The data suggest differences in important neutrophil proteins that might impact immunological processes. However, in vitro experiments revealed no apparent difference in the ability to control bacteria nor produce oxygen radicals. In subsets isolated from patients with septic shock, 24 proteins including cytochrome b-245 chaperone 1 had significantly higher abundance in Olfm4-H and 30 in Olfm4-L, including Fc receptor proteins. There was no correlation between Olfm4-H proportion and septic shock severity, but plasma Olfm4 concentration was elevated in septic shock. Thus, the Olfm4-H and Olfm4-L neutrophils have different proteomic profiles, but there was no evident functional significance of the differences in septic shock.

Background: Previous studies have found an increase in cardiac troponins (cTns) and echocardiographic abnormalities in patients with COVID-19 and reported their association with poor clinical outcomes. Whether acute injury occurs during the course of critical care and if it is associated with cardiac function is unknown.

The purpose of this study was to document the incidence of acute myocardial injury (AMInj) and echocardiographically defined left ventricular (LV) and right ventricular (RV) systolic dysfunction in consecutive patients admitted to an intensive care unit (ICU) for COVID-19. The relationship between AMInj and echocardiographic abnormalities during the first 14 days of ICU admission was studied. Finally, the association between echocardiographic findings, AMInj and clinical outcome was evaluated.

Methods: Seventy-four consecutive patients (≥18 years) admitted to the ICU at Linköping University Hospital between 19 Mar 2020 and 31 Dec 2020 for COVID-19 were included. High-sensitivity troponin-T (hsTnT) was measured daily for up to 14 days. Transthoracic echocardiography was conducted within 72 h of ICU admission. Acute myocardial injury was defined as an increased hsTnT > 14ng/l and a > 20% absolute change with or without ischaemic symptoms. LV and RV systolic dysfunction was defined as at least 2 abnormal indicators of systolic function specified by consensus guidelines.

Results: Increased hsTnT was observed in 59% of patients at ICU admission, and 82% developed AMInj with peak levels at 8 (3–13) days after ICU admission. AMInj was not statistically significantly associated with 30-day mortality but was associated with an increased duration of invasive mechanical ventilation (10 (3–13) vs. 5 days (0–9), p=0.001) as well as ICU length of stay (LOS) (19.5 (11–28) vs. 7 days (5–13), p=0.015). After adjustment for SAPS-3 and admission SOFA score, the effect of AMInj was significant only for the duration of mechanical ventilation (p=0.030).

The incidence of LV and RV dysfunction was 28% and 22%, respectively. Only indices of LV and RV longitudinal contractility (mitral and tricuspid annular plane systolic excursion) were associated with AMInj. Echocardiographic parameters were not associated with clinical outcome.

Conclusions: Myocardial injury is common in critically ill patients with COVID-19, with AMInj developing in more than 80% after ICU admission. In contrast, LV and RV dysfunction occurred in approximately one-quarter of patients. AMInj was associated with an increased need for mechanical ventilation and ICU LOS but neither AMInj nor ventricular dysfunction was significantly associated with mortality.

[No abstract available]

Background: Cell fusion is a natural process in normal development and tissue regeneration. Fusion between cancer cells and macrophages generates metastatic hybrids with genetic and phenotypic characteristics from both maternal cells. However, there are no clinical markers for detecting cell fusion in clinical context. Macrophage-specific antigen CD163 expression in tumor cells is reported in breast and colorectal cancers and proposed being caused by macrophages-cancer cell fusion in tumor stroma. The purpose of this study is to examine the cell fusion process as a biological explanation for macrophage phenotype in breast. Methods: Monocytes, harvested from male blood donor, were activated to M2 macrophages and co-cultured in ThinCert transwell system with GFP-labeled MCF-7 cancer cells. MCF7/macrophage hybrids were generated by spontaneous cell fusion, isolated by fluorescence-activated cell sorting and confirmed by fluorescence microscopy, short tandem repeats analysis and flow cytometry. CD163 expression was evaluated in breast tumor samples material from 127 women by immunohistochemistry. Results: MCF-7/macrophage hybrids were generated spontaneously at average rate of 2 % and showed phenotypic and genetic traits from both maternal cells. CD163 expression in MCF-7 cells could not be induced by paracrine interaction with M2-activated macrophages. CD163 positive cancer cells in tumor sections grew in clonal collection and a cutoff point greater than25 % of positive cancer cells was significantly correlated to disease free and overall survival. Conclusions: In conclusion, macrophage traits in breast cancer might be caused by cell fusion rather than explained by paracrine cellular interaction. These data provide new insights into the role of cell fusion in breast cancer and contributes to the development of clinical markers to identify cell fusion.

Propofol activates the gamma-aminobutyric acid type A receptor (GABA(A)R) and causes a reversible neurite retraction, leaving a thin, thread-like structure behind; it also reverses the transport of vesicles in rat cortical neurons. The awakening peptide orexin A (OA) inhibits this retraction via phospholipase D (PLD) and protein kinase CE (PKCE). The human SH-SY5Y cells express both GABA(A)Rs and orexin 1 and 2 receptors. These cells are used to examine the interaction between OA and the GABAAR. The effects of OA are studied with flow cytometry and immunoblotting. This study shows that OA stimulates phosphorylation on the serine residues of the GABA(A)R beta(2) subunit and that the phosphorylation is caused by the activation of PLD and PKCE. OA administration followed by propofol reduces the cell surface expression of the GABA(A)R, whereas propofol stimulation before OA increases the surface expression. The GABA(A)R beta(2) subunit is important for receptor recirculation, and the effect of OA on propofol-stimulated cells may be due to a disturbed recirculation of the GABA(A)R. (C) 2015 Wiley Periodicals, Inc.

Ethnopharmacological relevance: The emergence of multidrug-resistant strains of Mycobacterium tuberculosis underscores the need for continuous development of new and efficient methods to determine the susceptibility of isolates of Mycobacterium tuberculosis in the search for novel antimycobacterial agents. Natural products constitute an important source of new drugs, and design and implementation of antimycobacterial susceptibility testing methods are necessary to evaluate the different extracts and compounds. In this study we have explored the antimycobacterial properties of 50 ethanolic extracts from different parts of 46 selected medicinal plants traditionally used in Sudan to treat infectious diseases. Materials and methods: Plants were harvested and ethanolic extracts were prepared. For selected extracts, fractionation with hydrophilic and hydrophobic solvents was undertaken. A luminometry-based assay was used for determination of mycobacterial growth in broth cultures and inside primary human macrophages in the presence or absence of plant extracts and fractions of extracts. Cytotoxicity was also assessed for active fractions of plant extracts. Results: Of the tested extracts, three exhibited a significant inhibitory effect on an avirulent strain of Mycobacterium tubercluosis (H37Ra) at the initial screening doses (125 and 6.25 mu g/ml). These were bark and leaf extracts of Khaya senegalensis and the leaf extract of Rosmarinus officinalis L. Further fractions of these plant extracts were prepared with n-hexane, chloroform, ethyl acetate, n-butanol, ethanol and water, and the activity of these extracts was retained in hydrophobic fractions. Cytotoxicity assays revealed that the chloroform fraction of Khaya senegalensis bark was non-toxic to human monocyte-derived macrophages and other cell types at the concentrations used and hence, further analysis, including assessment of IC50 and intracellular activity was done with this fraction. Conclusion: These results encourage further investigations to identify the active compound(s) within the chloroform fraction of Khaya senegalensis bark. (C) 2014 Elsevier Ireland Ltd. All rights reserved.

Macrophages in the lung are the primary cells being infected by Mycobacterium tuberculosis (Mtb) during tuberculosis. Innate immune cells such as macrophages and neutrophils are first recruited to the site of infection, and mount the early immune protection against this intracellular pathogen. Neutrophils are short-lived cells and removal of apoptotic cells by resident macrophages is a key event in the resolution of inflammation and tissue repair. Such anti-inflammatory activity is not compatible with effective immunity to intracellular pathogens. We therefore investigated how uptake of apoptotic neutrophils by Mtb-activated human monocyte-derived macrophages modulates their function. We show that Mtb infection exerts a potent pro-inflammatory activation of human macrophages with enhanced gene activation and release of several cytokines (TNF, IL-1ß, IL-6, IL-18 and IL-10). This response was augmented by apoptotic neutrophils. Macrophages containing both Mtb and apoptotic cells showed a stronger cytokine expression than non-infected cells. The enhanced macrophage response is linked to apoptotic neutrophil-driven activation of the NLRP3 inflammasome and subsequent IL-1β signalling. We also demonstrate that apoptotic neutrophils not only modulate the inflammatory response, but also enhance the capacity of infected macrophages to control intracellular growth of virulent Mtb. Taken together, these results suggest a novel role for apoptotic neutrophils in the modulation of the macrophage-dependent inflammatory response, which can contribute to the early control of Mtb infection.

Activation of the NLRP3 inflammasome and subsequent generation of IL-1β is initiated in macrophages upon recognition of several stimuli. In the present work, we show that gain-of-function gene variants of inflammasome components known to predispose individuals to inflammatory disorders have a host-protective role during infection with Mycobacterium tuberculosis. By isolation of macrophages from patients and healthy blood donors with genetic variants in NLRP3 and CARD8 and subsequently infecting the cells by virulent M. tuberculosis, we show that these gene variants, combined, are associated with increased control of bacterial growth in human macrophages.

The standard treatment of tuberculosis (TB) takes six to nine months to complete and this lengthy therapy contributes to the emergence of drug-resistant TB. TB is caused by Mycobacterium tuberculosis (Mtb) and the ability of this bacterium to switch to a dormant phenotype has been suggested to be responsible for the slow clearance during treatment. A recent study showed that the replication rate of a non-virulent mycobacterium, Mycobacterium smegmatis, did not correlate with antibiotic susceptibility. However, the question whether this observation also holds true for Mtb remains unanswered. Here, in order to mimic physiological conditions of TB infection, we established a protocol based on long-term infection of primary human macrophages, featuring Mtb replicating at different rates inside the cells. During conditions that restricted Mtb replication, the bacterial phenotype was associated with reduced acid-fastness. However, these phenotypically altered bacteria were as sensitive to isoniazid, pyrazinamide and ethambutol as intracellularly replicating Mtb. In support of the recent findings with M. smegmatis, we conclude that replication rates of Mtb do not correlate with antibiotic tolerance.

Human embryonic stem cell (hESC) derived cardiomyocytes are in the present study being used for testing drug-induced cardiotoxicity in a biosensor set-up. The design of an in vitro testing alternative provides a novel opportunity to surpass previous methods based on rodent cells or cell lines due to its significantly higher toxicological relevance. In this report we demonstrate how hESC-derived cardiomyocytes release detectable levels of two clinically decisive cardiac biomarkers, cardiac troponin T and fatty acid binding protein 3, when the cardiac cells are exposed to the well-known cardioactive drug compound. doxorubicin. The release is monitored by the immuno-biosensor technique surface plasmon resonance, particularly appropriate due to its capacity for parallel and high-throughput analysis in complex media.