The encounter of disorders associated with antibodies to neuronal enzymes caused a paradigm shift in understanding the CNS autoimmunity.The autoimmune disorders targeting the 65kDa isoform of glutamic acid decarboxylase (GAD65) not only comprehends type 1 diabetes mellitus (T1DM), but also rather rare neurological disorders, including stiff-person syndrome (SPS), cerebellar ataxia, limbic encephalitis, and epilepsy.The patients with these autoimmune neurological disorders usually present with T1DM and suggests the presence of GAD65 antibodies.This is suggestive of autoimmune mechanisms for the development and worsening of these disorders.For better prognosis, its advanced screening and swift treatment are essential.Mesenchymal stem cells (MSCs) can be a promising salvage to these autoimmune disorders as they have proven hypoimmunogenic and immunomodulatory properties along with excellent regenerative ability.These self-renewing progenitor cells can differentiate into numerous cell types under explicit conditions, which includes neurons and pancreatic beta cells.MSCs annul the proinflammatory response in autoimmune disorders, may be through paracrine secretions, and hence, can help managing the hurricane of disturbed immunity.We present a link between the mechanisms driving autoimmune neurological diseases and T1DM in this review, based on the existence of GAD65 antibodies and an MSC-mediated solution for their treatment.

A T1DM-et az inzulint termelő hasnyálmirigy β-sejtjeinek T-sejt-függő pusztulása jellemzi. A feltételezett célantigének száma továbbra is növekszik, de nincs egyetértés az elsődleges antigén természetével kapcsolatban. Legnagyobb valószínűséggel ez az antigén maga az inzulin vagy a proinzulin. A teljes hosszúságú inzulin nagy dózisban nem alkalmazható intervenciós vizsgálatokban, annak metabolikus hatása miatt, ezért a pontos epitóp azonosítása elengedhetetlen. Korábban a hasnyálmirigyet körülvevő nyirokcsomókból izoláltak és oligoklonálisan tenyésztettek T-sejteket, amelyek felismerték az inzulin A-láncának 1–15. aminosavát. A diabetesspecifikus autoantigéneket azonosító publikációk száma nagyon korlátozott. Ennek ellenére több klinikai vizsgálat során számos különféle antigént alkalmaztak a β-sejtek pusztulásának lassítása vagy blokkolása céljából. Feltételeztük, hogy újonnan diagnosztizált T1DM-es betegek perifériás véréből ezen auto­reaktív T-sejtek azonosíthatóak. Célul tűztük ki továbbá, hogy meghatározzuk ezen sejtek antigénspecificitását.

Discovery of insulin in 1921 changed the lives of patients with type 1 diabetes (T1DM) forever. What had been a death sentence became a manageable, albeit chronic, disease. Insulin did not cure the disease, as it did not address the actual disease process, but instead treated its sequelae, namely elevated blood sugars. Importantly, insulin administration fails to ensure normoglycaemia. Even with the most sophisticated ‘near closed-loop’ methods, glucose homeostasis is not restored to normal. T1DM patients face complications, both short-term, such as hypo- and hyperglycaemia, and long-term, with increased glycosylation of proteins leading to eye, kidney, nervous system and other sequelae. These complications are associated with significant morbidity and mortality even after intensive insulin treatment. Nearly 100 years after the discovery of insulin, we continue to face the challenge of addressing the disease process itself, in order to fundamentally improve the life of these patients. There are major efforts to achieve just that: to completely arrest the autoimmune process destroying the insulin-producing cells in the pancreas, or at least significantly slow the process to blunt and delay short- and long-term complications. The aim of this Communication is to propose a novel assessment tool that would serve as a quantitative outcome measure by which therapies, short of clinical cure, may be compared and their true benefit to the treatment of diabetes assessed.

We previously reported that continuous 24-month costimulation blockade by abatacept significantly slows the decline of β-cell function after diagnosis of type 1 diabetes. In a mechanistic extension of that study, we evaluated peripheral blood immune cell subsets (CD4, CD8-naive, memory and activated subsets, myeloid and plasmacytoid dendritic cells, monocytes, B lymphocytes, CD4+CD25high regulatory T cells, and invariant NK T cells) by flow cytometry at baseline and 3, 6, 12, 24, and 30 months after treatment initiation to discover biomarkers of therapeutic effect. Using multivariable analysis and lagging of longitudinally measured variables, we made the novel observation in the placebo group that an increase in central memory (CM) CD4 T cells (CD4+CD45R0+CD62L+) during a preceding visit was significantly associated with C-peptide decline at the subsequent visit. These changes were significantly affected by abatacept treatment, which drove the peripheral contraction of CM CD4 T cells and the expansion of naive (CD45R0−CD62L+) CD4 T cells in association with a significantly slower rate of C-peptide decline. The findings show that the quantification of CM CD4 T cells can provide a surrogate immune marker for C-peptide decline after the diagnosis of type 1 diabetes and that costimulation blockade may exert its beneficial therapeutic effect via modulation of this subset.

To determine whether serum levels of 25-hydroxyvitamin D (25(OH)D) in young adults are associated with risk of type 1 diabetes mellitus (T1D), we conducted a prospective, nested case-control study among US active-duty military personnel with serum in the US Department of Defense Serum Repository, identifying 310 T1D cases diagnosed between 1997 and 2009 with at least 2 serum samples collected before disease onset and 613 controls matched to cases on age, sex, race/ethnicity, branch of military service, and dates of serum collection. Conditional logistic regression was used to estimate rate ratios and 95% confidence intervals. Among non-Hispanic whites, those with average 25(OH)D levels of ≥100 nmol/L had a 44% lower risk of developing T1D than those with average 25(OH)D levels <75 nmol/L (rate ratio = 0.56, 95% confidence interval: 0.35, 0.90, P for trend = 0.03) over an average follow-up of 5.4 years. In quintile analyses, T1D risk was highest among individuals whose 25(OH)D levels were in the lowest 20% of those measured. There was no association between 25(OH)D levels and risk of T1D among non-Hispanic blacks or Hispanics. Low 25(OH)D levels may predispose healthy, young, non-Hispanic white adults to the development of T1D.

OBJECTIVE We previously reported that 2 years of costimulation modulation with abatacept slowed decline of β-cell function in recent-onset type 1 diabetes (T1D). Subsequently, abatacept was discontinued and subjects were followed to determine whether there was persistence of effect. RESEARCH DESIGN AND METHODS Of 112 subjects (ages 6-36 years) with T1D, 77 received abatacept and 35 received placebo infusions intravenously for 27 infusions over 2 years. The primary outcome-baseline-adjusted geometric mean 2-h area under the curve (AUC) serum C-peptide during a mixed-meal tolerance test (MMTT) at 2 years-showed higher C-peptide with abatacept versus placebo. Subjects were followed an additional year, off treatment, with MMTTs performed at 30 and 36 months. RESULTS C-peptide AUC means, adjusted for age and baseline C-peptide, at 36 months were 0.217 nmol/L (95% CI 0.168-0.268) and 0.141 nmol/L (95% CI 0.071-0.215) for abatacept and placebo groups, respectively (P = 0.046). The C-peptide decline from baseline remained parallel with an estimated 9.5 months' delay with abatacept. Moreover, HbA1c levels remained lower in the abatacept group than in the placebo group. The slightly lower (nonsignificant) mean total insulin dose among the abatacept group reported at 2 years was the same as the placebo group by 3 years. CONCLUSIONS Costimulation modulation with abatacept slowed decline of β-cell function and improved HbA1c in recent-onset T1D. The beneficial effect was sustained for at least 1 year after cessation of abatacept infusions or 3 years from T1D diagnosis.

Abatacept delayed progression of type 1 diabetes (T1D) when administered soon after diagnosis. Its use in T1D is expanding to prevention trials and, therefore, it is important to fully characterize its immunosuppressive effect. We compared antibody responses to trivalent inactivated influenza vaccine (TIIV) administered during 2 consecutive seasons and to tetanus toxoid (TT) vaccine administered after 24 months of treatment in115 early onset T1D subjects randomly assigned to 24 months of abatacept (N=71) or placebo (N=34). Anti-influenza titers before TIIV were similar between the 2 treatment groups and both groups had significant increases after vaccination. Although the magnitude of antibody responses against some influenza serotypes was significantly lower (p<0.05) in abatacept compared with placebo recipients, no differences were observed in the proportion of subjects with protective titers against influenza after vaccination. The magnitude of antibody responses against TT also tended to be lower (p=0.06) in abatacept compared with placebo recipients, without affecting the proportion of subjects who achieved protective titers. We conclude that abatacept moderately decreases the magnitude of antibody responses to recall vaccination. Further studies are needed to assess its effect on primary immunization.

OBJECTIVE We examined changes in GAD65 and ICA-512 autoantibodies (GADA and IA-2A) during progression to type 1 diabetes (T1D). RESEARCH DESIGN AND METHODS Diabetes Prevention Trial–Type 1 (DPT-1) participants were assessed for changes in positivity and titers of GADA and IA-2A during the progression to T1D. RESULTS Among 99 progressors to T1D with GADA and IA-2A measurements at baseline and diagnosis (mean interval = 3.3 ± 1.5 years), GADA positivity changed little and GADA titers decreased (P < 0.01). In contrast, both IA-2A positivity and titers increased substantially (P < 0.001). Even among those positive at baseline, IA-2A titers increased from baseline to diagnosis (n = 57; P < 0.001), whereas GADA titers decreased (n = 80; P < 0.01). The same patterns of change were also evident among those positive for both autoantibodies (n = 48) at baseline. CONCLUSIONS IA-2A titers increase during the years before the diagnosis of T1D, even among those positive for IA-2A. In contrast, GADA titers tend to decline during those years.

Recently described forkhead box protein 3 (FoxP3) transcription factor is a key molecule in CD4+ CD25hi+ T-cell characterization. Invariant NK T (iNKT) cells are also characterized as regulatory cells modulating the immune response by rapidly producing T(h)1 and T(h)2 cytokines. We aimed to analyze cellular markers important in regulatory features of human iNKT cells and to study their role in functional assays. iNKT cells were single cell sorted from peripheral mononuclear cells of healthy individuals after immunostaining of invariant TCR α-chain. We found FoxP3 expression in human iNKT clones. Randomly selected iNKT cell clones (CD4+, double negative, CD8+) expressed FoxP3 mRNA and protein at different levels upon stimulation as supported by various approaches. FoxP3 mRNA and protein expression was detected in unstimulated iNKT cells as well. Furthermore, different stimulations changed the FoxP3 expression in iNKT cells over time and the most dramatic changes were observed upon anti-CD3 stimulation. Both the supernatant of iNKT cells and iNKT cells themselves exerted similar stimulation effects on PBMC proliferation in functional assays and these stimulations showed a negative correlation with FoxP3 expression. Our data indicate that the FoxP3 expression in iNKT cells may be a key transcriptional factor in controlling the regulatory function of the iNKT cells.

Background Glutamic acid decarboxylase (GAD) is a major target of the autoimmune response that occurs in type 1 diabetes mellitus. In animal models of autoimmunity, treatment with a target antigen can modulate aggressive autoimmunity. We aimed to assess whether immunisation with GAD formulated with aluminum hydroxide (GAD-alum) would preserve insulin production in recent-onset type 1 diabetes.Methods Patients aged 3-45 years who had been diagnosed with type 1 diabetes for less than 100 days were enrolled from 15 sites in the USA and Canada, and randomly assigned to receive one of three treatments: three injections of 20 mu g GAD-alum, two injections of 20 mu g GAD-alum and one of alum, or 3 injections of alum. Injections were given subcutaneously at baseline, 4 weeks later, and 8 weeks after the second injection. The randomisation sequence was computer generated at the TrialNet coordinating centre. Patients and study personnel were masked to treatment assignment. The primary outcome was the baseline-adjusted geometric mean area under the curve (AUC) of serum C-peptide during the first 2 h of a 4-h mixed meal tolerance test at 1 year. Secondary outcomes included changes in glycated haemoglobin A(1c) (HbA(1c)) and insulin dose, and safety. Analysis included all randomised patients with known measurements. This trial is registered with ClinicalTrials.gov, number NCT00529399.Findings 145 patients were enrolled and treated with GAD-alum (n=48), GAD-alum plus alum (n=49), or alum (n=48). At 1 year, the 2-h AUC of C-peptide, adjusted for age, sex, and baseline C-peptide value, was 0.412 nmol/L (95% CI 0.349-0.478) in the GAD-alum group, 0.382 nmol/L (0.322-0.446) in the GAD-alum plus alum group, and 0.413 nmol/L (0.351-0.477) in the alum group. The ratio of the population mean of the adjusted geometric mean 2-h AUC of C-peptide was 0.998 (95% CI 0.779-1.22; p=0.98) for GAD-alum versus alum, and 0.926 (0.720-1.13; p=0.50) for GAD-alum plus alum versus alum. HbA(1c), insulin use, and the occurrence and severity of adverse events did not differ between groups.Interpretation Antigen-based immunotherapy therapy with two or three doses of subcutaneous GAD-alum across 4-12 weeks does not alter the course of loss of insulin secretion during 1 year in patients with recently diagnosed type 1 diabetes. Although antigen-based therapy is a highly desirable treatment and is effective in animal models, translation to human autoimmune disease remains a challenge.

BACKGROUND:The immunopathogenesis of type 1 diabetes mellitus is associated with T-cell autoimmunity. To be fully active, immune T cells need a co-stimulatory signal in addition to the main antigen-driven signal. Abatacept modulates co-stimulation and prevents full T-cell activation. We evaluated the effect of abatacept in recent-onset type 1 diabetes. METHODS:In this multicentre, double-blind, randomised controlled trial, patients aged 6-45 years recently diagnosed with type 1 diabetes were randomly assigned (2:1) to receive abatacept (10 mg/kg, maximum 1000 mg per dose) or placebo infusions intravenously on days 1, 14, 28, and monthly for a total of 27 infusions over 2 years. Computer-generated permuted block randomisation was used, with a block size of 3 and stratified by participating site. Neither patients nor research personnel were aware of treatment assignments. The primary outcome was baseline-adjusted geometric mean 2-h area-under-the-curve (AUC) serum C-peptide concentration after a mixed-meal tolerance test at 2 years' follow-up. Analysis was by intention to treat for all patients for whom data were available. This trial is registered at ClinicalTrials.gov, NCT00505375. FINDINGS:112 patients were assigned to treatment groups (77 abatacept, 35 placebo). Adjusted C-peptide AUC was 59% (95% CI 6·1-112) higher at 2 years with abatacept (n=73, 0·378 nmol/L) than with placebo (n=30, 0·238 nmol/L; p=0·0029). The difference between groups was present throughout the trial, with an estimated 9·6 months' delay (95% CI 3·47-15·6) in C-peptide reduction with abatacept. There were few infusion-related adverse events (36 reactions occurred in 17 [22%] patients on abatacept and 11 reactions in six [17%] on placebo). There was no increase in infections (32 [42%] patients on abatacept vs 15 [43%] on placebo) or neutropenia (seven [9%] vs five [14%]). INTERPRETATION:Co-stimulation modulation with abatacept slowed reduction in β-cell function over 2 years. The beneficial effect suggests that T-cell activation still occurs around the time of clinical diagnosis of type 1 diabetes. Yet, despite continued administration of abatacept over 24 months, the decrease in β-cell function with abatacept was parallel to that with placebo after 6 months of treatment, causing us to speculate that T-cell activation lessens with time. Further observation will establish whether the beneficial effect continues after cessation of abatacept infusions. FUNDING:US National Institutes of Health.

There is a growing body of evidence to suggest that the autoimmunity observed in type 1 diabetes mellitus (T1DM) is the result of an imbalance between autoaggressive and regulatory cell subsets. Therapeutics that supplement or enhance the existing regulatory subset are therefore a much sought after goal in this indication. Here, we report the results of a double blind, placebo controlled, phase I clinical trial of a novel antigen-specific therapeutic in 12 subjects with recently diagnosed T1DM. Our primary objective was to test its safety. The study drug, human insulin B-chain in incomplete Freund's adjuvant (IFA) was administered as a single intramuscular injection, with subjects followed for 2 years. All subjects completed therapy and all follow-up visits. The therapy was generally safe and well-tolerated. Mixed meal stimulated C-peptide responses, measured every 6 months, showed no statistical differences between arms. All patients vaccinated with the autoantigen, but none who received placebo, developed robust insulin-specific humoral and T cell responses. Up to two years following the single injection, in peripheral blood from subjects in the experimental arm, but not the control arm, insulin B-chain-specific CD4+ T cells could be isolated and cloned that showed phenotypic and functional characteristics of regulatory T cells. The induction of a lasting, robust immune response generating autoantigen-specific regulatory T cells provides strong justification for further testing of this therapy in type 1 diabetes. (clinicaltrials.gov identifier NCT00057499).

Type 1 diabetes mellitus (T1DM) affects 1 in 300 people and the incidence of the disease is rising worldwide. T1DM is caused by chronic autoimmune destruction of the insulin-producing β-cells. The exact etiology and primary auto-antigen are not yet known. The autoimmune, chronic, and progressive nature of the disease raises the possibility of intervention, preferably by slowing down or stopping the destruction of the β-cells as early as the prediabetic stage. Since the 1980s, several attempts have been made to maintain β-cell function using immunosuppressive agents, immune modulation such as plasmapheresis, cytokine therapy, or antibody treatment. These agents were not diabetes specific; the occasionally observed beneficial effect did not compensate for the often very severe side effects. According to the latest assumption, the administration of diabetes-specific auto-antigens can elicit tolerance, which can prevent the destruction of the β-cells, hopefully without serious side effects. The authors summarize current understanding of the immunology of T1DM, review the trials on prevention, and discuss their vaccination study.

The secretion of IL-9, initially recognized as a Th2 cytokine, was recently attributed to a novel CD4 T cell subset termed Th9 in the murine system. However, IL-9 can also be secreted by mouse Th17 cells and may mediate aspects of the proinflammatory activities of Th17 cells. Here we report that IL-9 is secreted by human naive CD4 T cells in response to differentiation by Th9 (TGF-beta and IL-4) or Th17 polarizing conditions. Yet, these differentiated naive cells did not coexpress IL-17 and IL-9, unless they were repeatedly stimulated under Th17 differentiation-inducing conditions. In contrast to the naive cells, memory CD4 T cells were induced to secrete IL-9 by simply providing TGF-beta during stimulation, as neither IL-4 nor proinflammatory cytokines were required. Furthermore, the addition of TGF-beta to the Th17-inducing cytokines (IL-1beta, IL-6, IL-21, IL-23) that induce memory cells to secrete IL-17, resulted in the marked coexpression of IL-9 in IL-17 producing memory cells. The proinflammatory cytokine mediating TGF-beta-dependent coexpression of IL-9 and IL-17 was identified to be IL-1beta. Moreover, circulating monocytes were potent costimulators of IL-9 production by Th17 cells via their capacity to secrete IL-1beta. Finally, to determine whether IL-9/IL-17 coproducing CD4 cells were altered in an inflammatory condition, we examined patients with autoimmune diabetes and demonstrated that these subjects exhibit a higher frequency of memory CD4 cells with the capacity to transition into IL-9(+)IL-17(+) cells. These data demonstrate the presence of IL-17(+)IL-9(+) CD4 cells induced by IL-1beta that may play a role in human autoimmune disease.