liu.seSearch for publications in DiVA
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Autoantibodies related to type 1 diabetes in children
Linköping University, Department of Clinical and Experimental Medicine, Pediatrics. Linköping University, Faculty of Health Sciences.
2011 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Type 1 diabetes is an autoimmune disease resulting from destruction of the insulin producing beta cells in the pancreas. The patients need life-long heavy treatment and still complications, both acute and later in life, are common. The incidence of type 1 diabetes has increased rapidly during the last decades, especially among young children. The disease can be predicted by genes predisposing type 1 diabetes, mainly human leukocyte antigen (HLA) genes, together with presence of autoantibodies to beta-cell antigens, where multiple autoantibodies confer the highest risk. A number of immune system intervention trials are now ongoing aiming to halt the progression of the inflammatory process in the beta cells.

This thesis aimed to investigate the prevalence and levels of autoantibodies in healthy children and in children with type 1 diabetes. Another aim was to study different properties of one of these autoantibodies, such as to which epitopes the antibodies bind and the distribution of immunoglobulin (Ig)-G subclasses, after immunomodulatory treatment in children with type 1 diabetes.

We found that positivity to autoantibodies against glutamic acid decarboxylase (GADA) and tyrosine phosphatase like protein islet antigen-2 (IA-2A) was associated with HLA risk genotypes in 5-year old children from the general population. HLA risk genotypes seemed important for persistence of autoantibodies and for development of type 1 diabetes, while emergence of autoantibodies, especially transient autoantibodies, seemed to be more influenced by environmental factors. Improved methods for detection of autoantibodies are needed, for prediction of diabetes and for identification of high-risk individuals suitable for prevention treatments. Therefore, an assay for measurement of insulin autoantibodies (IAA), based on surface plasmon resonance (SPR), was developed. The main advantages of this method are that there is no need for labelling and that it is time-saving compared to the traditionally used radioimmunoassay (RIA), but further development of the method is needed.

Treatment with GAD-alum (Diamyd) in children with type 1 diabetes has shown to preserve residual insulin secretion. This clinical effect was accompanied by an increase in GADA levels. We investigated the epitope reactivity of GADA in both GAD-alum and placebo treated children, and found that binding to one of the tested epitopes was temporarily increased after injection of GAD-alum. This result suggests that the quality of GADA was, to some extent, transiently affected by the treatment. On the other hand, no changes in binding to epitopes associated with stiff person syndrome (SPS) were observed, which together with the lack of change in GAD65 enzyme activity further strengthens the safety of the treatment. We also observed that the distribution of IgG subclasses was changed by GAD-alum treatment, with a lower proportion of IgG1 and higher IgG3 and IgG4. Lower IgG1 and higher IgG4 suggest a temporary switch towards a protective Th2 immune response, which has previously been observed in the same individuals for other immunological markers.

In conclusion, measurement of autoantibodies related to type 1 diabetes is an important tool for studying the autoimmune process in pre-diabetic and type 1 diabetic children. In addition to the use as markers of disease progression, the autoantibodies may be used for studying the effects of immunomodulatory treatments on the humoral immune response.

Place, publisher, year, edition, pages
Linköping: Linköping University Electronic Press , 2011. , p. 116
Series
Linköping University Medical Dissertations, ISSN 0345-0082 ; 1218
National Category
Medical and Health Sciences
Identifiers
URN: urn:nbn:se:liu:diva-64593ISBN: 978-91-7393-276-9 (print)OAI: oai:DiVA.org:liu-64593DiVA, id: diva2:392919
Public defence
2011-02-18, Berzeliussalen, Hälsouniversitetet, Campus US, Linköpings universitet, Linköping, 09:00 (English)
Opponent
Supervisors
Available from: 2011-01-28 Created: 2011-01-28 Last updated: 2020-02-03Bibliographically approved
List of papers
1. Progression to type 1 diabetes and autoantibody positivity in relation to HLA-risk genotypes in children participating in the ABIS study
Open this publication in new window or tab >>Progression to type 1 diabetes and autoantibody positivity in relation to HLA-risk genotypes in children participating in the ABIS study
Show others...
2008 (English)In: Pediatric Diabetes, ISSN 1399-543X, E-ISSN 1399-5448, Vol. 9, no 3 PART 1, p. 182-190Article in journal (Refereed) Published
Abstract [en]

Background: Autoantibodies against beta-cell antigens together with human leukocyte antigen (HLA)-risk genotypes are used as predictive markers for type 1 diabetes (T1D). In this study, we have investigated the role of HLA-risk and -protective genotypes for development of beta-cell autoantibodies and progression to T1D in healthy children. Methods: T1D-related HLA genotypes and autoantibodies against glutamic acid decarboxylase [glutamic acid decarboxylase antibodies (GADA)] and islet antigen-2 (IA-2A) were studied at 1, 2.5 and 5 yr of age in unselected healthy children and children with T1D participating in the All Babies In Southeast Sweden (ABIS) study. Results: GADA or IA-2A positivity at 5 yr of age was associated with DR4-DQ8 haplotype and DR3-DQ2/DR4-DQ8 genotype. By the age of 6-7 yr, we identified 32 children with T1D among the 17 055 participants in the ABIS study. Eight of 2329 (0.3%) non-diabetic children had permanent autoantibodies, and 143 of 2329 (6%) children had transient autoantibodies. HLA-risk genotypes associated with T1D, whereas protective genotypes were seldom found in children with T1D. Children with permanent autoantibodies had more often risk-associated DR4-DQ8 haplotype than autoantibody-negative children. No associations with HLA-risk or -protective genotypes were found for transient autoantibodies. Conclusions: The strong relation between HLA-risk alleles and T1D once again confirmed that HLA-risk genotypes play an important role for development of T1D. However, HLA genotypes seem not to explain induction of autoantibodies, especially transient autoantibodies, in the general population, emphasizing the role of environmental factors in the initiation of autoimmunity. It seems that HLA-risk genotypes are responsible for maturation of the permanent autoantibody response. © 2008 The Authors Journal compilation © 2008 Blackwell Munksgaard.

National Category
Medical and Health Sciences
Identifiers
urn:nbn:se:liu:diva-42864 (URN)10.1111/j.1399-5448.2008.00369.x (DOI)69621 (Local ID)69621 (Archive number)69621 (OAI)
Available from: 2009-10-10 Created: 2009-10-10 Last updated: 2017-12-13
2. An indirect competitive immunoassay for insulin autoantibodies based on surface plasmon resonance
Open this publication in new window or tab >>An indirect competitive immunoassay for insulin autoantibodies based on surface plasmon resonance
Show others...
2008 (English)In: Biosensors and Bioelectronics, ISSN 0956-5663, Vol. 24, no 4, p. 876-881Article in journal (Refereed) Published
Abstract [en]

We have developed a sensitive and specific method based on surface plasmon resonance (SPR) for detection of insulin autoantibodies (IAA) in serum samples from individuals at high risk of developing type 1 diabetes (T1D). When measuring trace molecules in undiluted sera with label-free techniques like SPR, non-specific adsorption of matrix proteins to the sensor surface is often a problem, since it causes a signal that masks the analyte response. The developed method is an indirect competitive immunoassay designed to overcome these problems. Today, IAA is mainly measured in radio immunoassays (RIAs), which are time consuming and require radioactively labeled antigen. With our SPR-based immunoassay the overall assay time is reduced by a factor of >100 (4 days to 50 min), while sensitivity is maintained at a level comparable to that offered by RIA.

Keywords
SPR, Type 1 diabetes, Insulin autoantibodies, Indirect competitive immunoassay, RIA
National Category
Other Basic Medicine
Identifiers
urn:nbn:se:liu:diva-12469 (URN)10.1016/j.bios.2008.07.018 (DOI)
Note
The status of article IV on the day of defence was: Accepted.Available from: 2008-09-06 Created: 2008-09-06 Last updated: 2018-01-13Bibliographically approved
3. GAD autoantibody epitope pattern after GAD-alum treatment in children and adolescents with type 1 diabetes
Open this publication in new window or tab >>GAD autoantibody epitope pattern after GAD-alum treatment in children and adolescents with type 1 diabetes
Show others...
2012 (English)In: Pediatric Diabetes, ISSN 1399-543X, E-ISSN 1399-5448, Vol. 13, no 3, p. 244-250Article in journal (Refereed) Published
Abstract [en]

Aims/hypothesis. Previously we have shown that two injections of glutamic acid decarboxylase formulated in alum (GAD-alum) preserved residual insulin secretion in children and adolescents with recent onset type 1 diabetes (T1D), and was accompanied by an increase in GAD autoantibody (GADA) titers. The aim of the present study was to investigate whether GAD-alum treatment affected the GADA epitope pattern.

Methods. Serum samples of patients treated with GAD-alum (n=33) or placebo (n=27), at baseline and 1, 3, 9, and 15 months after initiation of treatment, were tested for their binding capacity to specific GADA epitopes in an epitope specific radioligand-binding assay with six GAD65-specific recombinant Fab (rFab) (b96.11, DPA, DPD, MICA3, b78 and N-GAD65 mAb).

Results. For the period included in this study (baseline to 15 months) no difference in variability of binding to any of the tested rFab were observed. However, a higher median response to the b96.11-defined epitope in the first 3 months after the initial injection was observed in GAD-alum treated patients (-8.1%, min -72.4%, max 39.6%) compared to patients receiving placebo (1.5%, min -28.3%, max 28.6%) (p=0.02). This effect was especially evident in GAD-alum treated patients who experienced an increase of more than 100% in their GADA titer from baseline to 3 months (n=27), where we observed an 10.8% (-10.8%, min -72.4%, max 30.5%) increase in binding to the b96.11 epitope over the  first 3 months post initial injection (p=0.04). Subsequently the recognition of the b96.11-defined epitope in the GAD-alum group decreased between 3 and 15 months (8.3%, min -17.1%, max 36.7%) compared to the placebo group (-2.4%, min -32.8%, max 30.1%) (p<0.05) and returned to levels similar to that observed at baseline. Correlations between GADA titer and epitope binding for b96.11 and DPD were observed in the placebo group, but not in the GADalum group, at 3 and 15 months after initial treatment.

Conclusions/interpretation. We conclude that administration of GAD-alum temporarily induced increased binding to one epitope specificity of GADA.

Place, publisher, year, edition, pages
John Wiley & Sons, 2012
Keywords
Type 1 diabetes, autoantibody, epitope, GAD
National Category
Medical and Health Sciences
Identifiers
urn:nbn:se:liu:diva-64592 (URN)10.1111/j.1399-5448.2011.00802.x (DOI)000303194000004 ()
Note
funding agencies|Swedish Child Diabetes Foundation (Barndiabetesfonden)||Medical Research Council of Southeast Sweden||Diamyd Medical AB||National Institutes of Health| DK26190 DK53004 DK17047 |American Diabetes Association||Available from: 2011-01-28 Created: 2011-01-28 Last updated: 2017-12-11Bibliographically approved
4. GAD-alum treatment in patients with type 1 diabetes and the subsequent effect on GADA IgG subclass distribution, GAD(65) enzyme activity and humoral response
Open this publication in new window or tab >>GAD-alum treatment in patients with type 1 diabetes and the subsequent effect on GADA IgG subclass distribution, GAD(65) enzyme activity and humoral response
Show others...
2010 (English)In: Clinical Immunology, ISSN 1521-6616, E-ISSN 1521-7035, Vol. 137, no 1, p. 31-40Article in journal (Refereed) Published
Abstract [en]

We have previously shown that two injections of 20 mu g GAD-alum to recent onset type 1 diabetic children induced GADA levels in parallel to preservation of insulin secretion. Here we investigated if boosted GADA induced changes in IgG1, 2, 3 and 4 subclass distributions or affected GAD(65) enzyme activity. We further studied the specific effect of GAD-alum through analyses of IA-2A, tetanus toxoid and total IgE antibodies. Serum from children receiving GAD alum or placebo was collected pre-treatment and after 3, 9, 15 and 21 months. At 3 months a reduced percentage of IgG1 and increased IgG3/IgG4 were detected in GAD-alum treated. Further, IA-2A, IgE and tetanus toxoid antibodies, as well as GAD(65) enzyme activity, were unaffected confirming the specific effect of treatment. In the GAD-alum group, higher pretreatment GADA were associated to more pronounced C-peptide preservation. The induced IgG3/IgG4 and reduced IgG1 suggest a Th2 deviation of the immune response.

Place, publisher, year, edition, pages
Elsevier Science B.V., Amsterdam, 2010
Keywords
Immunotherapy, GAD(65), GAD-alum, GADA, Type 1 diabetes, T1D, IgG, IgG subclass
National Category
Medical and Health Sciences
Identifiers
urn:nbn:se:liu:diva-60511 (URN)10.1016/j.clim.2010.06.001 (DOI)000282204900005 ()
Note

Original Publication: Mikael Chéramy, Camilla Skoglund, Ingela Johansson, Johnny Ludvigsson, Christiane S Hampe and Rosaura Casas, GAD-alum treatment in patients with type 1 diabetes and the subsequent effect on GADA IgG subclass distribution, GAD(65) enzyme activity and humoral response, 2010, CLINICAL IMMUNOLOGY, (137), 1, 31-40. http://dx.doi.org/10.1016/j.clim.2010.06.001 Copyright: Elsevier Science B.V., Amsterdam http://www.elsevier.com/

Available from: 2010-10-15 Created: 2010-10-15 Last updated: 2017-12-12Bibliographically approved

Open Access in DiVA

Autoantibodies related to type 1 diabetes in childre(1728 kB)5236 downloads
File information
File name FULLTEXT01.pdfFile size 1728 kBChecksum SHA-512
619c9ab2e2f303a74d54fb13bf4f2db98196c6c4a88a2caff1920c1f47ecef130a3b98be520d24ccd5a58f3821d11adc41c6fe2f735fcaa20acac5219ce56b09
Type fulltextMimetype application/pdf
cover(73 kB)134 downloads
File information
File name COVER01.pdfFile size 73 kBChecksum SHA-512
a59797a99b900f25aac6f1e3ddffaa7f5cf7444881d72cc4859be3e79cc2adbb1a72b62f6c3a32b44c94f58697ac16b01b2fc8be292c40834833fcffcad7437a
Type coverMimetype application/pdf
Order online >>

Authority records

Skoglund, Camilla

Search in DiVA

By author/editor
Skoglund, Camilla
By organisation
PediatricsFaculty of Health Sciences
Medical and Health Sciences

Search outside of DiVA

GoogleGoogle Scholar
Total: 5237 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

isbn
urn-nbn

Altmetric score

isbn
urn-nbn
Total: 1376 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf