| 1. |
- Axelsson, Stina, et al.
(författare)
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Cellular and Humoral Immune responses in Type 1 Diabetic patients participating in a Phase III GAD-alum Intervention Trial
- 2013
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Ingår i: Diabetes Care. - : American Diabetes Association. - 0149-5992 .- 1935-5548. ; 36:11, s. 3418-3424
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVEGAD formulated in aluminum hydroxide (GAD-alum) has previously been shown to induce preservation of residual insulin secretion in recent-onset type 1 diabetes, but recent phase II and III GAD-alum trials failed to reach primary outcomes. The European phase III study was therefore closed after 15 months, and only a minority of patients completed the 30 months of follow-up.RESEARCH DESIGN AND METHODSThis study aimed to characterize cellular and humoral responses in the Swedish patients (n = 148) participating in the phase III trial, receiving four (4D) or two (2D) GAD-alum doses or placebo. Serum GAD(65) antibody (GADA) levels, GADA IgG1-4 subclass distribution, cytokine secretion, and proliferative responses in peripheral blood mononuclear cells (PBMCs) were analyzed.RESULTSThe GAD(65)-induced cytokine profile tended to switch toward a predominant Th2-associated profile over time both in the 2D and 4D group. The groups also displayed increased GADA levels and PBMC proliferation compared with placebo, whereas GADA IgG subclass distribution changed in 4D patients.CONCLUSIONSBoth 2D and 4D patients displayed GAD(65)-specifc cellular and humoral effects after GAD-alum treatment, but at different time points and magnitudes. No specific immune markers could be associated with treatment efficacy.
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| 2. |
- Axelsson, Stina, et al.
(författare)
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Cryopreserved peripheral blood mononuclear cells are suitable for the assessment of immunological markers in type 1 diabetic children
- 2008
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Ingår i: Cryobiology. - : Elsevier BV. - 0011-2240 .- 1090-2392. ; 57:3, s. 201-208
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Tidskriftsartikel (refereegranskat)abstract
- Cryopreserved peripheral blood mononuclear cells (PBMC) are commonly used when assessing immune responses in clinical trials, both for practical reasons and to minimize interassay variation, as samples are often collected and studied over time. This study investigated the effect of cryopreservation on cytokine and chemokine secretion, and on expression of regulatory T-cell associated markers, in samples from children with type 1 diabetes. PBMC were cultured before and after cryopreservation either with GAD(65) or PHA. Secretion of cytokines (IL-5, -6, -10, -12, -13 -17, IFN-gamma and TNF-alpha) and chemokines (IP-10, MCP-1, MIP-1 alpha, MIP-1 beta and RANTES) was analysed in cell supernatants using multiplex fluorochrome technique (Luminex). Expression of FOXP3 and TGF-beta mRNA was detected by multiplex real-time RT-PCR. Increased spontaneous secretion of IL-6, -10, -12, -13, IFN-gamma and MCP-1, and mRNA expression of FOXP3 and TGF-beta, was detected after cryopreservation. Stimulation with GAD65 induced higher levels of IL-6, IFN-gamma, TNF-alpha and MIP-1 alpha, whereas lower secretion was found for IL-10 and IL-13 in cryopreserved PBMC. Stimulation with PHA induced lower secretion of IP-10, MCPA and RANTES and FOXP3 mRNA expression after cryopreservation. Thus, cryopreserved PBMC were suitable to assess the immunological markers included in this study, even though their expression could differ from freshly handled cells.
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| 3. |
- Axelsson, Stina, et al.
(författare)
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Decreased GAD(65) -specific Th1/Tc1 phenotype in children with Type 1 diabetes treated with GAD-alum.
- 2012
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Ingår i: Diabetic Medicine. - : Wiley-Blackwell. - 0742-3071 .- 1464-5491. ; 29:10, s. 1272-1278
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Tidskriftsartikel (refereegranskat)abstract
- Aim The balance between T helper cell subsets is an important regulator of the immune system and is often examined after immune therapies. We aimed to study the immunomodulatory effect of glutamic acid decarboxylase (GAD) 65 formulated with aluminium hydroxide (GAD-alum) in children with Type 1 diabetes, focusing on chemokines and their receptors. Methods Blood samples were collected from 70 children with Type 1 diabetes included in a phase II clinical trial with GAD-alum. Expression of CC chemokine receptor 5 (CCR5) and CCR4 was analysed on CD4+ and CD8+ lymphocytes after in vitro stimulation with GAD(65) using flow cytometry, and secretion of the chemokines CCL2, CCL3 and CCL4 was detected in peripheral blood mononuclear cell supernatants with Luminex. Results Expression of Th1-associated CCR5 was down-regulated following antigen challenge, together with an increased CCR4/CCR5 ratio and CCL2 secretion in GAD-alum-treated patients, but not in the placebo group. Conclusion Our results suggest that GAD-alum treatment has induced a favourable immune modulation associated with decreased Th1/Tc1 phenotypes upon antigen re-challenge, which may be of importance for regulating GAD(65) immunity. © 2012 The Authors. Diabetic Medicine © 2012 Diabetes UK.
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| 4. |
- Axelsson, Stina, et al.
(författare)
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Early induction of GAD(65)-reactive Th2 response in type 1 diabetic children treated with alum-formulated GAD(65)
- 2010
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Ingår i: Diabetes/Metabolism Research Reviews. - : John Wiley and Sons. - 1520-7552 .- 1520-7560. ; 26:7, s. 559-568
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Tidskriftsartikel (refereegranskat)abstract
- Background We have previously shown that two injections of 20 mu g alum-formulated glutamic acid decarboxylase 65 (GAD(65)) (GAD-alum; Diamyd (R)) in children with recent-onset type 1 diabetes lead to preservation of residual insulin secretion. In vitro cytokine production at the 15 months follow-up indicated immunomodulation. In the present study, we took advantage of peripheral blood mononuclear cells, cryopreserved during early follow-ups, to investigate whether the immunomodulatory effect of GAD-alum was apparent earlier after treatment, preceding the changes previously reported at 15 months.Methods Peripheral blood mononuclear cells from 70 type 1 diabetic children, randomly assigned GAD-alum (n = 35) or placebo (n = 35), that had been frozen at baseline (n = 27) and after 1 (n = 58), 3 (n = 67) and 9 (n = 66) months, were stimulated in vitro with GAD(65), tyrosine phosphatase-like protein IA-2 peptide, insulin peptide, GAD-alum, alum formulation or phytohaemagglutinin. Interleukin (IL)-5, -6, -10, -12, -13, -17, tumour necrosis factor and interferon-gamma were measured in cell supernatants and serum samples using Luminex. Expression of FOXP3 and transforming growth factor-beta was determined by real-time reverse transcription polymerase chain reaction.Results Already 1 month after the first injection, GAD(65)-induced IL-5 and IL-13 together with FOXP3 were enhanced in GAD-alum-treated patients compared to those with placebo. The in vitro response at 3 and 9 months was characterized by a broader range of cytokines in the treated group. Notably, only the T-helper 2-associated cytokines IL-5 and IL-13 together with FOXP3 increased continuously over time.Conclusions Treatment with GAD-alum in type 1 diabetic children induced an early T-helper 2 immune enhanced response to GAD(65), followed by a wider spectrum of cytokines at 3 and 9 months. Copyright (C) 2010 John Wiley & Sons, Ltd.
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| 5. |
- Axelsson, Stina, 1981-
(författare)
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GAD65 An Immunomodulator in Type 1 Diabetes
- 2012
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Type 1 diabetes (T1D) is caused by a deficiency of insulin as a result of an autoimmune destruction of the pancreatic ² -cells. A possibility to preserve remaining ² -cells in children with newly diagnosed T1D is of great importance since sustained ² -cell function is recognized to result in reduced end-organ complications. Glutamic acid decarboxylase 65 (GAD65) is one of the major antigens targeted by self-reactive T cells in T1D, and immunomodulation with GAD65 formulated in aluminum (GAD-alum) has been considered both in prevention and treatment of T1D. Results from a Phase II trial have shown clinical effect of subcutaneous injections with GAD-alum, this was unfortunately not fully confirmed in the following larger Phase III trial which therefore was closed after 15 months. The general aim of this thesis was to study the immunomodulatory effect of GAD-alum-treatment in children with T1D participating in the Phase II and Phase III trials. We hypothesized that treatment with GAD-alum contributes to the preservation of residual insulin secretion through deviation of the GAD65-specific immune response from a destructive to a protective process, accompanied by a shift from T helper (Th) 1 towards a predominant Th2 profile. In the Phase II trial, GAD-alum-treated patients responded with an early GAD65-specific Th2 skewed cytokine secretion, with highest IL-5 and IL-13 secretion in clinical responders. Also, the CCR4/CCR5 ratio indicating balance between Th2/Tc2 and Th1/Tc1 responses, increased in treated patients. The recall response to GAD65 was characterized by a wide range of cytokines, but the relative contribution of each cytokine suggests a shift towards a more pronounced Th2-associated profile over time. Induction of a CD4+ cell subset upon GAD65-stimulation 4 years after treatment, suggesting clonal expansion of the memory T-cell compartment upon antigen re-challenge, was seen in parallel to a persistent GAD65-specific cytokine response. Finally, even if the phase III trial failed to reach the primary endpoint at 15 months, a subgroup analysis showed that the treatment had an effect on preservation of residual insulin secretion, but the effect was not seen until after 30 months. Taken together, these results suggest that GAD-alum treatment might exert its effect through induction of an early Th2 skewed immune response which tends to deviate away from a destructive Th1/Tc1 response upon GAD65 re-challenge, and generation of GAD65-specific memory T cells that produce cytokines and exert effector responses which may be important for regulating GAD65 immunity. Continued research to better understand how immunomodulation with autoantigen modifies T-cell responses and also which patients are suitable for treatment, is crucial for optimizing future intervention trials using ² -cell antigens.
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| 6. |
- Axelsson, Stina, et al.
(författare)
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Long-Lasting Immune Responses 4 Years after GAD-Alum Treatment in Children with Type 1 Diabetes
- 2011
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Ingår i: PLOS ONE. - : Public Library of Science. - 1932-6203. ; 6:12
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Tidskriftsartikel (refereegranskat)abstract
- A phase II clinical trial with glutamic acid decarboxylase (GAD) 65 formulated with aluminium hydroxide (GAD-alum) has shown efficacy in preserving residual insulin secretion in children and adolescents with recent-onset type 1 diabetes (T1D). We have performed a 4-year follow-up study of 59 of the original 70 patients to investigate long-term cellular and humoral immune responses after GAD-alum-treatment. Peripheral blood mononuclear cells (PBMC) were stimulated in vitro with GAD(65). Frequencies of naive, central and effector memory CD4+ and CD8+ T cells were measured, together with cytokine secretion, proliferation, gene expression and serum GAD(65) autoantibody (GADA) levels. We here show that GAD-alum-treated patients display increased memory T-cell frequencies and prompt T-cell activation upon in vitro stimulation with GAD(65), but not with control antigens, compared with placebo subjects. GAD(65)-induced T-cell activation was accompanied by secretion of T helper (Th) 1, Th2 and T regulatory cytokines and by induction of T-cell inhibitory pathways. Moreover, post-treatment serum GADA titres remained persistently increased in the GAD-alum arm, but did not inhibit GAD(65) enzymatic activity. In conclusion, memory T- and B-cell responses persist 4 years after GAD-alum-treatment. In parallel to a GAD(65)-induced T-cell activation, our results show induction of T-cell inhibitory pathways important for regulating the GAD(65) immunity.
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| 7. |
- Axelsson, Stina, et al.
(författare)
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Preserved C-peptide 30 months after GAD-alum treatment of children and adolescents with recent-onset type 1 diabetes, and its relation to immune markers
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Glutamic acid decarboxylase 65 kDa isoform (GAD65) is a major autoantigen in type 1 diabetes (T1D). Although alum-formulated GAD65 (GAD-alum) induced preservation of residual insulin secretion in a previous clinical Phase II trial, recent Phase II and Phase III trials failed to reach their primary end-points. The European Phase III trial was therefore closed after 15 months, and the 30 months follow-up period was completed only for a minority of the patients. This study aimed to assess whether GAD-alum preserved β-cell function in those recent-onset T1D patients who completed their 30 months visit in the European Phase III trial, and to characterize their GAD65-induced cytokine secretion and proliferation. Peripheral blood mononuclear cells (PBMC) were isolated at baseline and after 1, 3, 9, 15 and 21 months from the 148 Swedish subjects included in the Phase III GAD-alum trial, and also at 30 months from 45 patients who had reached the final visit before the trial was closed. Patients had been randomly assigned into three arms: 4 doses of GAD-alum (4D), 2 doses of GAD-alum followed by two doses of placebo (2D), or 4 doses of placebo. Cytokine secretion was detected in cell culture supernatants by Luminex, after 7 days of in vitro culture. Cell proliferation was determined by 3H thymidine incorporation assay. Fasting and stimulated C-peptide was analysed in serum. Patients treated with 2 doses of GAD-alum had less decline of both fasting (p=0.040) and stimulated C-peptide (p=0.012) after 30 months, and a larger proportion of these patients preserved >25% of their initial stimulated C-peptide AUC compared to placebo (p=0.012). Both 2D and 4D patients showed increased PBMC proliferation to GAD65 and a cytokine profile that tended to switch towards a more predominant Th2 associated profile over time. The results support the concept of GAD-alum treatment, but no specific immune markers have been identified.
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| 8. |
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| 9. |
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| 10. |
- Chéramy, Mikael, et al.
(författare)
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GAD65 autoantibody (GADA) responses in Type 1 diabetes patients participating in a phase III GAD-alum intervention trial
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Glutamic acid decarboxylase 65 kDa isoform (GAD65) is a major autoantigen in type 1 diabetes (T1D). Although aluminum-formulated GAD65 (GAD-alum) induced preservation of residual insulin secretion in a previous clinical phase II trial, recent phase II and III trials failed to reach their primary end-points. The European phase III trial was therefore closed after 15 months, and the entire study period was completed only for a minority of the patients. This study aimed to characterize GAD65 autoantibodies (GADA) and Tyrosine phosphatase IA-2 autoantibody (IA-2A) levels, GADA IgG1-4 subclass distribution, B-cell frequencies/phenotypes and cytokine secretion. We also assessed whether GAD-alum preserved β-cell function in the small subgroup of Swedish patients who completed the 30 months visit. Serum samples and peripheral blood mononuclear cells (PBMC) were collected at baseline and after 1, 3, 9, 15 and 21 months from the 148 Swedish subjects included in the trial, and also at 30 months from the 45 patients who reached the final visit. Patients were randomly assigned to; i) 4 doses of GAD-alum (4D), ii) 2 doses of GAD-alum followed by two doses of placebo (2D), or iii) 4 doses of placebo.GADA titers were induced both in the 4D and 2D group compared to placebo, and 4D patients also displayed a higher GADA fold-change after receiving the two additional injections compared to the 2D group. The 4D group switched to a higher frequency of GADA IgG4, associated to a Th2 type response at 9 months, whereas an association between GADA fold-change and GAD65-induced in vitro cytokine secretion was observed in the 2D group. These findings suggest that the humoral response, induced by the 2D treatment, seems to be associated with a GAD65-specific cellular response, while 4D induces a distinct humoral response. Even though GADA titers were elevated, no changes in B-cell frequencies or phenotype were observed in any group. IA-2A levels declined at a similar rate in all groups during the trial.The subgroup of patients who completed the 30 month visit receiving 2 doses of GAD-alum had less decline of both fasting and stimulated C-peptide after 30 months compared to placebo. These results support the concept of GAD-alum treatment, but no specific immune markers have been identified.
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