Onset Type 1 Diabetes Patients Research Articles

Monocytes in type 1 diabetes families exhibit high cytolytic activity and subset abundances that correlate with clinical progression.

Monocytes are immune regulators implicated in the pathogenesis of type 1 diabetes (T1D), an autoimmune disease that targets insulin-producing pancreatic β cells. We determined that monocytes of recent onset (RO) T1D patients and their healthy siblings express proinflammatory/cytolytic transcriptomes and hypersecrete cytokines in response to lipopolysaccharide exposure compared to unrelated healthy controls (uHCs). Flow cytometry measured elevated circulating abundances of intermediate monocytes and >2-fold more CD14+CD16+HLADR+KLRD1+PRF1+ NK-like monocytes among patients with ROT1D compared to uHC. The intermediate to nonclassical monocyte ratio among ROT1D patients correlated with the decline in functional β cell mass during the first 24 months after onset. Among sibling nonprogressors, temporal decreases were measured in the intermediate to nonclassical monocyte ratio and NK-like monocyte abundances; these changes coincided with increases in activated regulatory T cells. In contrast, these monocyte populations exhibited stability among T1D progressors. This study associates heightened monocyte proinflammatory/cytolytic activity with T1D susceptibility and progression and offers insight to the age-dependent decline in T1D susceptibility.

1286-P: Plasma-Induced Signatures Measured at Type 1 Diabetes (T1D) Onset Correlate with Post-onset Beta-Cell Function

Significant phenotypic diversity exists among T1D patients, supporting the existence of distinct disease endotypes (e.g. duration of the post-onset partial remission period) . To broaden our understanding of T1D heterogeneity and its relationship to disease progression and therapeutic responsiveness, we studied 566 new onset T1D patients (241 females, 325 males; mean age 16.5 +/- 8.2 years) that had participated in TrialNet clinical trials: TN02/MMF DZB; TN05/anti-CD20; TN08/GAD-alum; TN09/CTLA4-Ig; TN14/Canakinumab; and TN19/ATG-GCSF. Baseline samples were analyzed with a sensitive bioassay, where subject plasma is used to induce transcription in a well-controlled peripheral blood mononuclear cell population. The response was measured with a microarray, data were normalized, and transcripts exhibiting the highest median absolute deviation within each trial were identified. Weighted gene correlation network analysis was used to cluster patterns of variation into modules of co-expressed transcripts. Co-expression networks were correlated with clinical data collected over the 24-months following clinical onset. In the placebo arms of all 6 trials, we identified modules that significantly correlated with post-onset C-peptide AUC, post-onset insulin dose, Insulin-Dose Adjusted A1c, and/or the rate of C-peptide decline. This suggests that the baseline analyses identified modules that differentiated subjects in terms of post-onset beta-cell function, supporting the existence of T1D endotypes. While TN02, TN08, and TN14 did not show overall efficacy in slowing post-onset C-peptide decline, the module correlations with phenotypes related to beta-cell function were fewer in number and of lesser statistical significance in the treatment arms of all 6 trials. This suggests that there was greater beta-cell function in the treatment arms of all trials, and that varying degrees of immunomodulation had occurred even in those trials that did not show efficacy. Disclosure A.Bedrat: None. S.Jia: None. M.Roethle: None. K.Dew: None. S.M.Cabrera: None. C.Lin: None. M.Hessner: None. Funding National Institutes of Health (R01DK121528)

185-OR: T-Cell Receptor Repertoires during Type 1 Diabetes Development

In type 1 diabetes (T1D) , T cells target and destroy pancreatic beta cells. T cells express T cell receptors (TCRs) which recognize peptide antigens, and each TCR is unique to a given T cell. To understand the TCR repertoire during T1D development, we used next generation sequencing to detect TCRβ chains from longitudinal peripheral blood DNA samples at four time points from genetically at-risk cases (n=29) who progressed to T1D and age/sex/HLA matched controls (n=25) beginning early in life (median age 1.4 years) in the Diabetes Autoimmunity Study in the Young (DAISY) . Over 50 million TCRβ chains were sequenced, and the repertoires became less diverse (i.e., more clonal) over time with age in both groups (p<0.001) . Principal component analyses of TCRβ V gene usage identified a subset of cases (n=11) that had higher frequencies of specific V genes beginning early in life before islet autoantibody seroconversion compared to the remaining cases and controls. The subset of cases were more likely to be double positive for GADA and IA-2A compared to the remaining cases (p=0.008) . Previously, we sequenced ∼3,500 αβTCRs from the residual islets of T1D organ donors (n=9) and identified 44 TCRs that recognize preproinsulin (PPI) . We searched for the PPI-reactive TCRβs (identical V gene, J gene, and CDR3) , and 15 TCRβs (6 CD4 and 9 CD8) were found to be shared in DAISY participants. The PPI CD4 TCRβ sequences (templates) were more frequent in cases compared to controls, 180 vs. 14 (p<0.001) , but CD8 PPI templates were similar between cases and controls, 29 vs. 25. Using an algorithm to identify additional TCRs predicted to recognize similar PPI peptides, we found that these TCR clusters were more frequent in cases compared to controls and accumulated after islet autoantibody seroconversion. Lastly, PPI TCRs and clusters were identified in a separate cohort of new onset T1D patients (n=143, mean age 12.5 years) . Our results demonstrate that islet-derived TCR clusters have the potential to be a biomarker prior to clinical T1D onset. Disclosure A.M.Mitchell: None. M.Nakayama: None. A.W.Michels: Employee; ImmunoMolecular Therapeutics, Stock/Shareholder; ImmunoMolecular Therapeutics. E.E.Baschal: None. K.Mcdaniel: None. L.Pyle: None. K.Waugh: None. A.Steck: None. L.Yu: None. P.Gottlieb: Advisory Panel; Janssen Research & Development, LLC, ViaCyte, Inc., Other Relationship; IM Therapeutics, Research Support; Caladrius Biosciences, Inc., Immune Tolerance Network, National Institute of Diabetes and Digestive and Kidney Diseases, Novo Nordisk, Precigen, Inc., Tolerion, Inc. M.Rewers: Consultant; Janssen Research & Development, LLC, Medscape, Provention Bio, Inc., Research Support; Dexcom, Inc., JDRF, Roche Diagnostics USA. Funding National Institutes of Health (DK108868, DK110845, DK032083, DK032493, DK116073) Juvenile Diabetes Research Foundation (3-PDF-2020-943-A-N) Leona M. & Harry B. Helmsley Charitable Trust (2103-05093) Colorado Clinical and Translational Science Institute (TR002535)

Pancreas Whole Tissue Transcriptomics Highlights the Role of the Exocrine Pancreas in Patients With Recently Diagnosed Type 1 Diabetes.

Although type 1 diabetes (T1D) is primarily a disease of the pancreatic beta-cells, understanding of the disease-associated alterations in the whole pancreas could be important for the improved treatment or the prevention of the disease. We have characterized the whole-pancreas gene expression of patients with recently diagnosed T1D from the Diabetes Virus Detection (DiViD) study and non-diabetic controls. Furthermore, another parallel dataset of the whole pancreas and an additional dataset from the laser-captured pancreatic islets of the DiViD patients and non-diabetic organ donors were analyzed together with the original dataset to confirm the results and to get further insights into the potential disease-associated differences between the exocrine and the endocrine pancreas. First, higher expression of the core acinar cell genes, encoding for digestive enzymes, was detected in the whole pancreas of the DiViD patients when compared to non-diabetic controls. Second, In the pancreatic islets, upregulation of immune and inflammation related genes was observed in the DiViD patients when compared to non-diabetic controls, in line with earlier publications, while an opposite trend was observed for several immune and inflammation related genes at the whole pancreas tissue level. Third, strong downregulation of the regenerating gene family (REG) genes, linked to pancreatic islet growth and regeneration, was observed in the exocrine acinar cell dominated whole-pancreas data of the DiViD patients when compared with the non-diabetic controls. Fourth, analysis of unique features in the transcriptomes of each DiViD patient compared with the other DiViD patients, revealed elevated expression of central antiviral immune response genes in the whole-pancreas samples, but not in the pancreatic islets, of one DiViD patient. This difference in the extent of antiviral gene expression suggests different statuses of infection in the pancreas at the time of sampling between the DiViD patients, who were all enterovirus VP1+ in the islets by immunohistochemistry based on earlier studies. The observed features, indicating differences in the function, status and interplay between the exocrine and the endocrine pancreas of recent onset T1D patients, highlight the importance of studying both compartments for better understanding of the molecular mechanisms of T1D.

Elevated Biomarkers of NETosis in the Serum of Pediatric Patients With Type 1 Diabetes and Their First-Degree Relatives.

Type 1 diabetes (T1D) is an autoimmune disorder with unambiguous involvement of both innate and adaptive immune mechanisms in the destruction of pancreatic beta cells. Recent evidence demonstrated that neutrophils infiltrate the pancreas prior to disease onset and therein extrude neutrophil extracellular traps (NETs), web-like structures of DNA and nuclear proteins with a strong pro-inflammatory biologic activity. Our previous work showed that T1D NETs activate dendritic cells, which consequently induce IFNγ-producing Th1 lymphocytes. The aim of this study was to assess direct ex vivo biomarkers of NETosis in the serum of recent onset and long-term pediatric T1D patients, their first-degree relatives and healthy controls. To this end we evaluated serum levels of myeloperoxidase (MPO), neutrophil elastase (NE), proteinase 3 (PR3), protein arginine deiminase 4 (PAD4), LL37 and cell-free DNA-histone complexes in sex- and age-matched cohorts of T1D first-degree relatives, recent-onset T1D patients, and in patients 12 months after clinical manifestation of the disease. Our data shows that disease onset is accompanied by peripheral neutrophilia and significant elevation of MPO, NE, PR3, PAD4 and cell-free DNA-histone complexes. Most biomarkers subsequently decrease but do not always normalize in long-term patients. First-degree relatives displayed an intermediate phenotype, except for remarkably high levels of LL37. Together, this report provides evidence for the presence of ongoing NETosis in pediatric patients with T1D at time of clinical manifestation of the disease, which partly subsides in subsequent years.

159-LB: High-Affinity ZnT8 Autoantibodies by Electrochemiluminescence Assay Improve the Risk Prediction for Type 1 Diabetes

Background: A cohort of children with single ZnT8 autoantibody (ZnT8A) positivity were identified in two large clinical trials, Autoimmunity Screening for Kids (ASK) and Diabetes Autoimmunity Study in the Young (DAISY), and their risk of type 1 diabetes (T1D) have never been studied. Methods: Three cohorts were analyzed using a high-affinity electrochemiluminescence (ECL) ZnT8A assay including 302 new onset T1D patients, 135 children positive for ZnT8A by standard radio-binding assay (RBA) from 23400 children screened in ASK study, and 123 children with multiple autoantibodies or single ZnT8A by RBA from 2547 children in DAISY study. Results: ECL-ZnT8A had a similar sensitivity with RBA-ZnT8A in the cohort of 302 new onset T1D patients (62.3% vs. 61.9%). In ASK, 135/23400 of general population children were positive for RBA-ZnT8A and 64/135 were found as single ZnT8A only without other islet autoantibodies. Of 64 children with single ZnT8A, only 14.1% (9/64) were detectable by ECL-ZnT8A. Antibody-affinity analysis revealed that the ZnT8A in RBA but not confirmed by ECL were of low affinity and they were easily disappeared during the follow-up behaving as ‘transient’ positivity. In terms of T1D classification from stage 1 to stage 3, positive predictive value (PPV) of ECL-ZnT8A (61/70 [87.1%]) was significantly higher than that of RBA-ZnT8A (73/137 [53.3%]; P<0.0001). The cumulative risk of clinical T1D development with ZnT8A confirmed by ECL (16/66) was significantly enhanced during a short time of follow-up, compared with ZnT8A not confirmed by ECL (1/43; p=0.023). Similarly in DAISY participants, 11/2547 children were identified as single ZnT8A by RBA while only three who developed T1D were detected ECL-ZnT8A. Conclusions: Large proportion of ZnT8A by current standard RBA are single ZnT8A with majority at low risk in population-based screening while ECL-ZnT8A can discriminate high risk from low risk and are highly predictive for T1D development. Disclosure X. Jia: None. L. He: None. D. Miao: None. K. Waugh: None. C. Geno rasmussen: None. F. Dong: None. M. Rewers: Advisory Panel; Self; Provention Bio, Inc., Consultant; Self; RTI, Research Support; Self; Janssen Research & Development, LLC, JDRF. L. Yu: None. Funding Diabetes Research Center (P30DK116073); JDRF (2-SRA-2018-533-S-B, 2-SRA-2020-965-S-B, 1-SRA-2016-208-S-B); National Institutes of Health (DK32083)

High-Affinity ZnT8 Autoantibodies by Electrochemiluminescence Assay Improve the Risk Prediction for Type 1 Diabetes

Background: A cohort of children with single ZnT8 autoantibody (ZnT8A) positivity were identified in two large clinical trials, Autoimmunity Screening for Kids (ASK) and Diabetes Autoimmunity Study in the Young (DAISY), and their risk of type 1 diabetes (T1D) have never been studied. Methods: Three cohorts were analyzed using a high-affinity electrochemiluminescence (ECL) ZnT8A assay including 302 new onset T1D patients, children with positive ZnT8A (n=135) by radio-binding assay (RBA) from 23400 general population children screened in the ASK study, and children (n=123) with multiple islet autoantibodies (IAbs) or single ZnT8A by RBA identified from 2547 longitudinally followed cases in DAISY. In addition, 1098 samples with all IAbs negative were also analyzed for ECL-ZnT8A. Findings: In ASK study, 0.58% (135/23400) of children were detected ZnT8A by RBA and 47.4% (64/135) of these ZnT8A were unexpectedly found as ZnT8A alone. Of 64 children with single ZnT8A, only 9 were detectable by ECL-ZnT8A. ZnT8A by RBA not confirmed by ECL were found low affinity with low risk. Positive predictive value of ECL-ZnT8A, in terms of high risk from T1D stage 1 to stage 3, was significantly higher (P<0.0001) than that of RBA-ZnT8A. Similarly in 2547 children of DAISY cohort, 11 cases in total were identified as single ZnT8A while only three who developed clinical T1D were detected ECL-ZnT8A. Interpretation: Majority of single ZnT8A positivity detected in screening by RBA were of low affinity with low T1D risk while ZnT8A detected by ECL assay were of high-affinity with high prediction for T1D development. Funding: JDRF, NIH Declaration of Interests: The authors declare no conflict of interest related to this study. Ethics Approval Statement: All subjects were provided written or electronic informed consent and all studies were approved by the University of Colorado Institutional Review Board.

Analysis of Incident DKA in the Indiana New Onset T1D Patient Population

Background/Objective: Diabetic ketoacidosis (DKA) is a life-threatening complication of type 1 diabetes (T1D) resulting from ketone body production and metabolic acidosis occurring due to insulin deficiency. We sought to define the occurrence of DKA amongst pediatric patients presenting with new-onset T1D in Indiana and to determine whether patterns of DKA were affected by the COVID-19 pandemic. &#x0D; &#x0D; Methods: This was a retrospective chart review for patients &lt;18 years admitted to Riley Children’s Hospital with a clinical diagnosis of new onset T1D who had available chemistry values. Patients diagnosed from March 23- June 30, 2020 and over the same period in 2019 were included. DKA was classified as mild (bicarbonate 10-15 mmol/L) or severe (bicarbonate &lt;10 mmol/L). &#x0D; &#x0D; Results: Ninety-four patients met inclusion criteria. The total number of incident T1D cases in 2019 and 2020 were similar (48 vs. 46, respectively). Similarly, there was no significant difference in rates of DKA (21 in 2019 vs. 25 in 2020; p&gt;0.05). Of the 94 patients, 49% met criteria for DKA; 79% of cases were classified as severe and 21% as mild. More males were diagnosed with DKA in both 2019 and 2020 (61% of DKA cases). Non-Hispanic whites comprised 75% of all new onset T1D patients and no differences in race or ethnicity were present amongst those presenting in DKA. &#x0D; &#x0D; Conclusion: DKA was present in nearly half of all new onset pediatric T1D cases in Indiana in 2019 and 2020. There was no observed impact of the COVID-19 pandemic on T1D or DKA. &#x0D; &#x0D; Impact and Implications: DKA is common amongst pediatric patients with new onset T1D in Indiana. Prompt recognition of symptoms is needed to prevent this life-threatening complication of T1D.

Distinct two different ages associated with clinical profiles of acute onset type 1 diabetes in Chinese patients

There are abundant variations in the phenotypes and genetics of type 1 diabetes (T1D) patients across different races. This study aimed to assess differences between juvenile acute onset (JAO) and adult acute onset in Chinese T1D patients. Seven hundred and fifty-one acute onset T1D patients were divided into two groups by the patient onset age as follows: the juvenile acute onset group (≤20years, JAO group) and the adult acute onset group (>20years, AAO group). Clinical characteristics, islet autoantibodies, and HLA class II haplotypes and genotypes were compared between these two groups. In comparison with AAO patients, JAO patients had significantly lower relative weights and lower triglyceride levels (P<.001, P<.01, respectively) but higher frequency of ketoacidosis (P<.001), higher daily insulin dosage (Pc <.001), higher HbA1c (Pc <.05), and higher HDL-cholesterol levels (Pc <.01). The JAO group showed a higher prevalence of IA-2A, ZnT8A, and multiple autoantibodies than that in the AAO group (P<.001, P<.01, P<.001, respectively). Haplotypes for DRB1*0301-DQA1*03-DQB1*0201, DR3, DR4, DR9, and DR3/DR9 genotypes are highly associated with JAO susceptibility, whereas only DR3 and DR9 genotypes confer risk for AAO. In the JAO group but not the AAO group, DR3 is related to ZnT8A, and DR3/DR9 is related to IA-2A and multiple autoantibodies. These observations suggest that JAO patients markedly differ from AAO patients in their clinical manifestations and genetics in the Chinese T1D population. Notably, the DR3/DR9 genotype can facilitate the appearance of IA-2A or multiple autoantibodies in JAO patients.

Type 1 diabetes onset at young age is associated with compromised bone quality.

Women with type 1 diabetes (T1D) are at increased risk for fracture. We studied the association of T1D and young age at T1D onset (T1D onset before 20 years) on bone structural quality. 24 postmenopausal women with T1D (mean age 60.9 years, mean T1D duration 41.7 years) and 22 age, sex- and body mass index (BMI)-matched controls underwent dual X-ray absorptiometry (DXA) measured areal bone mineral density (aBMD) at the lumbar spine, hip and distal radius. Bone mass, geometry and estimated bone strength were assessed at distal and shaft of non-dominant radius and tibia using peripheral quantitative computed tomography (pQCT). Postmenopausal women with T1D had lower trabecular volumetric bone mineral density (vBMD) (LSM ± SEM; 166.1 ± 8.2 vs 195.9 ± 8.3 mg/cm3, p = 0.02) and compressive bone strength (24.6 ± 1.8 vs 30.1 ± 1.9 mg2/mm4, p = 0.04) at the distal radius compared to controls adjusting for age, BMI and radius length. At the distal radius, patients with young onset T1D had lower total vBMD (258.7 ± 19.7 vs 350.8 ± 26.1 mg/cm3, p = 0.02) and trabecular vBMD (141.4 ± 11.6 vs 213.6 ± 15.4 mg/cm3, p = 0.003) compared to adult onset T1D patients adjusting for age, BMI and the radius length. At the tibial shaft, young onset T1D patients had larger endosteal circumference (39.1 ± 1.2 vs 32.1 ± 1.6 mm, p = 0.005) with similar periosteal circumference (67.1 ± 0.9 vs 65.1 ± 1.2 mm, p = 0.2) resulting in reduced cortical thickness (4.4 ± 0.1 vs 5.2 ± 0.1 mm, p = 0.004) compared to adult onset T1D patients adjusting for age, BMI and the tibia length. There was no difference in the lumbar spine, femoral neck, total hip and distal radius DXA-measured aBMD between subjects with T1D and controls. T1D is associated with lower trabecular vBMD at the distal radius. T1D onset before age 20 is associated with cortical bone size deficits at the tibial shaft.

Insulin-Like Growth-Factor Axis Collectively Identifies Pre–Type 1 Diabetes

Autoantibodies (AAb) against beta cell antigens are useful biomarkers for type 1 diabetes (T1D) prediction; however, staging of pre-T1D requires lengthy and invasive glucose tolerance testing. A need exists for additional serum biomarkers reflective of metabolic and immunologic dysregulation to test concurrently with AAb. The insulin-like growth factor (IGF) family, consisting of IGF1 and IGF2, has been shown to promote insulin action and possess immunoregulatory properties. Their activity is regulated by at least seven IGF binding proteins (IGFBPs). We hypothesized that IGF1 and IGF2 levels or bioavailability are reduced during T1D development. Total serum IGF1, IGF2, and IGFBP1-7 levels were measured in an age-matched (12.0 ± 3.7 years), cross-sectional cohort of AAb negative (AAb-) controls (CTRL) (n=74); AAb- first-degree relatives (AAb- FDR, n=55); FDR positive (AAb+ FDR) for one (n=23) or multiple (n=26) of GAD65, IA-2, or ZnT8 AAbs; new onset (NO) T1D patients (n=63, duration 1.0 ± 0.7 months); and established T1D patients (n=68, duration 4.4 ± 3.7 years). IGF1 and IGF2 levels were significantly lower in AAb+ FDR compared to AAb- FDR (204 ± 117 vs. 346 ± 160 ng/mL, p&amp;lt;0.001; 701 ± 496 vs. 1054 ± 721 ng/mL, p&amp;lt;0.01). Lower IGF1 levels were noted in single AAb+ FDR (183 ± 112 ng/mL, p&amp;lt;0.0001), while lower IGF2 levels remained significant in multiple AAb+ FDR only (686 ± 535 ng/mL, p&amp;lt;0.05). IGFBP1 levels were increased in AAb+ FDR compared to AAb- FDR (3.6 ± 3.2 vs. 1.8 ± 1.7 ng/mL, p&amp;lt;0.01), and this was apparent in single AAb+ FDR (4.5 ± 4.0 ng/mL, p&amp;lt;0.001). IGFBP7 levels were significantly lower in multiple AAb+ FDR as compared to AAb- FDR (79 ± 21 vs. 95 ± 22 ng/mL, p&amp;lt;0.05). Additionally, we established a multiple logistic regression model evaluating age, IGFs, and IGFBPs (IGFBP1, -3, and -7), which could effectively discriminate AAb+ FDR from CTRL (AUC = 0.84). These data suggest a dysregulated IGF axis is present prior to symptomatic T1D and may provide new biomarkers to improve disease prediction. Disclosure M. Shapiro: None. C. Wasserfall: None. A.R. Schultz: None. S.M. McGrail: None. M.J. Haller: None. D. Schatz: None. M.A. Atkinson: Other Relationship; Self; Patent Issued. T.M. Brusko: Stock/Shareholder; Self; OneVax, LLC. Advisory Panel; Self; Caladrius Biosciences, Inc.. Consultant; Self; Merck &amp; Co., Inc., Sanofi-Aventis.

Mitochondrial bioenergetics of immune cells in Type 1 diabetes

Abstract Mitochondrial (mito) bioenergetics of circulating cells change as a function of disease in Alzheimer’s, fibromyalgia, cancer, and Type 2 diabetes. We are exploring the use of mito-bioenergetics as a biomarker of Type 1 diabetes (T1D) progression and immune cell activation. T1D is a polygenic autoimmune disease in which an inflammatory leukocytic infiltrate into pancreatic islets results in destruction of insulin-producing β-cells. Autoantibody synthesis is currently used as a biomarker, but is a poor predictor of T1D since the majority of β-cells are destroyed prior to autoantibody seroconversion. We hypothesize that T1D is a chronic inflammatory disease in which conditions of oxidative stress will diminish the mitochondrial reserve capacity of immune cells and provide a surrogate marker for T1D. We compared mito-bioenergetics of murine immune cells derived from the spleen, pancreatic lymph node and bone marrow between diabetic and pre-diabetic Non-Obese Diabetic (NOD) mice. We show that mitochondrial reserve capacity is reduced in circulating CD4+ T cells from diabetic mice, but not in pre-diabetic mice during T1D progression. To explore the role of mitochondrial oxidative stress on diabetogenic CD4+ T cell effector responses, we used mito-TEMPO to scavenge mitochondrial reactive oxygen species (mROS). Mito-TEMPO reduced IFNγ synthesis in a primary recall assay by 0.24-fold and the combination of mito and cytosolic TEMPO increased Treg-associated IL-2 by 2.5-fold, suggesting that mROS have a causal role in modulating T cell effector responses critical for T1D pathology. We plan to perform human translational studies on mito-bioenergetics of PBMCs from recent onset T1D patients and further dissect the role of mROS on T1D.

Circulating Differentially Methylated Amylin DNA as a Biomarker of β-Cell Loss in Type 1 Diabetes.

In type 1 diabetes (T1D), β-cell loss is silent during disease progression. Methylation-sensitive quantitative real-time PCR (qPCR) of β-cell-derived DNA in the blood can serve as a biomarker of β-cell death in T1D. Amylin is highly expressed by β-cells in the islet. Here we examined whether demethylated circulating free amylin DNA (cfDNA) may serve as a biomarker of β-cell death in T1D. β cells showed unique methylation patterns within the amylin coding region that were not observed with other tissues. The design and use of methylation-specific primers yielded a strong signal for demethylated amylin in purified DNA from murine islets when compared with other tissues. Similarly, methylation-specific primers detected high levels of demethylated amylin DNA in human islets and enriched human β-cells. In vivo testing of the primers revealed an increase in demethylated amylin cfDNA in sera of non-obese diabetic (NOD) mice during T1D progression and following the development of hyperglycemia. This increase in amylin cfDNA did not mirror the increase in insulin cfDNA, suggesting that amylin cfDNA may detect β-cell loss in serum samples where insulin cfDNA is undetected. Finally, purified cfDNA from recent onset T1D patients yielded a high signal for demethylated amylin cfDNA when compared with matched healthy controls. These findings support the use of demethylated amylin cfDNA for detection of β-cell-derived DNA. When utilized in conjunction with insulin, this latest assay provides a comprehensive multi-gene approach for the detection of β-cell loss.

Concise Review: Cell-Based Therapies and Other Non-Traditional Approaches for Type 1 Diabetes.

The evolution of Type 1 diabetes (T1D) therapy has been marked by consecutive shifts, from insulin replacement to immunosuppressive drugs and targeted biologics (following the understanding that T1D is an autoimmune disease), and to more disease‐specific or patient‐oriented approaches such as antigen‐specific and cell‐based therapies, with a goal to provide efficacy, safety, and long‐term protection. At the same time, another important paradigm shift from treatment of new onset T1D patients to prevention in high‐risk individuals has taken place, based on the hypothesis that therapeutic approaches deemed sufficiently safe may show better efficacy if applied early enough to maintain endogenous β cell function, a concept supported by many preclinical studies. This new strategy has been made possible by capitalizing on a variety of biomarkers that can more reliably estimate the risk and rate of progression of the disease. More advanced (“omic”‐based) biomarkers that also shed light on the underlying contributors of disease for each individual will be helpful to guide the choice of the most appropriate therapies, or combinations thereof. In this review, we present current efforts to stratify patients according to biomarkers and current alternatives to conventional drug‐based therapies for T1D, with a special emphasis on cell‐based therapies, their status in the clinic and potential for treatment and/or prevention. Stem Cells 2016;34:809–819

Updates on Immune Therapies in Type 1 Diabetes.

Multiple clinical trials investigating the efficacy and safety of immunotherapeutic interventions in new onset type 1 diabetes (T1D) have failed to yield long term clinical benefit. Lack of efficacy has frequently been attributed to an incomplete understanding of the pathways involved in T1D and the use of single immunotherapeutic agents. Recent mechanistic studies have improved our knowledge of the complex etiopathogenesis of T1D. This in turn has provided the framework for new and ongoing clinical trials in new onset T1D patients and at-risk subjects. Focus has also shifted towards the potential benefits of synergistic combinatorial approaches, both in terms of efficacy and the potential for reduced side effects. These efforts seek to develop intervention strategies that will preserve β-cell function, and ultimately prevent and reverse clinical disease.

CXCR3, CXCL10 and type 1 diabetes

Type 1 diabetes (T1D) is due to antigen-specific assaults on the insulin producing pancreatic β-cells by diabetogenic T-helper (Th)1 cells. (C-X-C motif) ligand (CXCL)10, an interferon-γ inducible Th1 chemokine, and its receptor, (C-X-C motif) receptor (CXCR)3, have an important role in different autoimmune diseases. High circulating CXCL10 levels were detected in new onset T1D patients, in association with a Th1 autoimmune response. Furthermore β-cells produce CXCL10, under the influence of Th1 cytokines, that suppresses their proliferation. Viral β-cells infections induce cytokines and CXCL10 expression, inducing insulin-producing cell failure in T1D. CXCL10/CXCR3 system plays a critical role in the autoimmune process and in β-cells destruction in T1D. Blocking CXCL10 in new onset diabetes seems a possible approach for T1D treatment.

B cell depletion in autoimmune diabetes: insights from murine models

Introduction: The incidence of type 1 diabetes (T1D) is rising for reasons that largely elude us. New strategies aimed at halting the disease process are needed. One type of immune cell thought to contribute to T1D is the B lymphocyte. The first Phase II trial of B cell depletion in new onset T1D patients indicated that this slowed the destruction of insulin-producing pancreatic beta cells. The mechanistic basis of the beneficial effects remains unclear.Areas covered: Studies of B cell depletion and deficiency in animal models of T1D. How B cells can influence T cell-dependent autoimmune diabetes in animal models. The heterogeneity of B cell populations and current evidence for the potential contribution of specific B cell subsets to diabetes, with emphasis on marginal zone B cells and B1 B cells.Expert opinion: B cells can influence the T cell response to islet antigens and B cell depletion or genetic deficiency is associated with decreased insulitis in animal models. New evidence suggests that B1 cells may contribute to diabetes pathogenesis. A better understanding of the roles of individual B cell subsets in disease will permit fine-tuning of therapeutic strategies to modify these populations.

Changes in GAD65Ab-specific antiidiotypic antibody levels correlate with changes in C-peptide levels and progression to islet cell autoimmunity.

The previously reported absence of 65-kDa glutamate decarboxylase antibody (GAD65Ab)-specific antiidiotypic antibodies (anti-Id) in type 1 diabetes (T1D) patients at clinical onset could be due to an inability to mount an antibody response to GAD65Ab or a longitudinal decline in anti-Id levels. We investigated anti-Id levels in longitudinal samples obtained from T1D patients (n = 41) (clinical diagnosis - 12 months), and latent autoimmune diabetes in adults (LADA) patients (n = 32) who received alum-formulated human recombinant GAD65 (baseline - 12 months). We also determined anti-Id levels in a small cohort of Type 2 diabetes patients during their development of autoimmune T cell responses. At clinical onset T1D patients presented no or low anti-Id levels. However, 22/41 T1D patients showed ≥50% increase in GAD65Ab-specific anti-Id levels during follow-up; peaking at 3 (n = 1), 6 (n = 10), 9 (n = 10), or 12 (n = 1) months. Increasing anti-Id levels marked patients who experienced a temporary increase in C-peptide levels. Anti-Id levels correlated significantly with glycated hemoglobin and C-peptide levels at 6 and 9 months (P values ranged from <0.001 to <0.05). In LADA patients receiving placebo, anti-Id levels declined in seven of nine patients, whereas four of five patients receiving 20 μg alum-formulated human recombinant GAD65 showed increasing anti-Id levels. Changes in anti-Id and C-peptide levels closely correlated (P < 0.0001). The significant decline in anti-Id levels (P = 0.03) in T2D patients developing T cell autoimmune responses supports our hypothesis that declining anti-Id levels are associated with developing islet autoimmunity. The close association between GAD65Ab-specific anti-Id levels and β-cell function may provide a novel marker for the progression of autoimmune diabetes.