Diabetes-associated Autoantibodies Research Articles

Features of Slowly Progressive Type 1 Diabetes Mellitus in Overweight Adolescents

Background: he obesity epidemic has led to an increase in the incidence of type 1 diabetes mellitus (T1DM) on the background of overweight. The combination of T1DM and obesity can lead to an erroneous diagnosis of type 2 diabetes (T2DM). Methods: The study included 35 adolescents with T1DM. Inclusion criteria were obesity at onset, high titer of diabetes-associated autoantibodies, and insulin requirement less than 0.5 U/kg with a diabetes duration of more than 6 months. We assessed the level of HbA1c, fasting level of insulin and c-peptide, and level during the Mixed-Meal Tolerance Test, the immunological status of GADA, IA-2, ZnT8, ICA. Results: The age of onset was 12.7 years [10.6; 14.5], the tanner stage of puberty was 4 [3; 5]. Sex distribution: boys (n = 25) - 71.5%, girls (n = 10) - 28.5%. HbA1c at the time of onset equaled 8,9% [7.4; 10.45]. Ketosis/diabetic ketoacidosis was registered in 47.8%. The duration of the diabetes was 1.7 years at the moment of examination [0.7; 2.9]. The fasting level of C-peptide - 1.37 mμg/ml [1.0.9; 2.19], insulin level (n = 26) - 13.93 uU/ml [9.57; 19.77]. The maximum level of stimulated secretion of C-peptide (n = 21) - 5.13 mμg/ml [3.05; 6.07], of insulin secretion (n = 21) - 58.59 uU/ml [31.02; 79.74]. Higher HOMA of insulin resistance (n = 25) was detected in 72% of the examined patients. In the study of pancreatic autoantibodies, an increase in ICA was detected in 57% (median of titer 1.68 [0.28;11.7]), IA-2 - 67% (192.8 ME/ml [65; 310.1]), GAD - 59% (90.25 ME/ml [32.27; 214.6]), ZnT8 - 82% (350.5 [90.4; 506.05]). The presence of 2 or more autoantibodies is found in 94% of cases. Dyslipidemia was observed in 34.8%, arterial hypertension was identified in 23% of patients. Received therapy: insulin 82%; metformin 0.02%; metformin + insulin 5.7%. Median daily dose per patient was 0.3 U/kg [0.2; 0.5]. Conclusion: T1DM in adolescents with obesity and overweight has a similar clinical picture both with T1DM (insulin dependence, high titer of autoantibodies, ketosis) and T2DM (slow progression of the disease, low insulin requirement, preserved secretion of c-peptide, and insulin for more than 1.5 years). We hypothesize that obesity and insulin resistance may contribute to DM onset at an earlier date, even if a satisfactory function of pancreatic beta-cells is still preserved. Given that the onset of the disease in our group falls on adolescence it seems that pubertal insulin resistance also contributes to the features of the course of the disease. Understanding the role of obesity in the progression of disorders of carbohydrate metabolism will allow postponing the acute manifestation of the disease and initiation of insulin therapy through lifestyle modifications in patients at risk. A long period of preserved insulin secretion opens up the possibility of new personalized therapies.

Autoantibodies against zinc transporter 8 further stratify the autoantibody-defined risk for type 1 diabetes in a general population of schoolchildren and have distinctive isoform binding patterns in different forms of autoimmune diabetes: results from the Karlsburg Type 1 Diabetes Risk Study.

To evaluate the diagnostic relevance of autoantibodies against zinc transporter 8 (ZnT8) in schoolchildren from the general population as well as in people with autoimmune diabetes. A total of 137 schoolchildren positive for at least one of the three major diabetes-associated autoantibodies, without diabetes heredity or preselection on HLA typing, from the Karlsburg Type 1 Diabetes Risk Study, as well as 102 people at type 1 diabetes onset, 88 people with latent autoimmune diabetes in adults and 119 people with type 2 diabetes, were analysed for different ZnT8 autoantibody variants. Zinc transporter 8 autoantibody positivity was found in 18% of autoantibody-positive schoolchildren, with a noticeable association with other autoantibodies associated with type 1 diabetes and disease progression. Furthermore, ZnT8 autoantibody positivity was associated with diabetes progression in schoolchildren positive for autoantibodies against insulinoma-associated antigen-2 (IA-2) and, importantly, in seven IA-2 autoantibody-negative schoolchildren. Additionally, ZnT8 autoantibodies were found in 56% of people with type 1 diabetes, predominantly directed against all three ZnT8 variants and comparable to schoolchildren with multiple autoantibodies. In contrast, ZnT8 autoantibodies were detected in 10% of people with latent autoimmune diabetes in adults, none of them with reactivity to all three isoforms. Zinc transporter 8 autoantibodies are useful markers for prediction of type 1 diabetes in a general population, further stratifying the risk of progression in autoantibody-positive children. ZnT8 autoantibodies are also important markers in adult-onset diabetes, with a completely different reaction pattern in type 1 diabetes in comparison to latent autoimmune diabetes in adults, and may therefore help to differentiate between the two forms.

The prevalence of newly diagnosed autoimmune diseases among patients with Graves' disease and autoimmune polyglandular syndrome of adults

The aim of this study was to determine the frequency of occurrence of APS type 2, 3 among patients with Graves disease. Sera of 94 patients with Gravess disease, 116 patients with APS 24 types and 80 healthy subjects were screened for 21-OH Ab, insulin-Ab (IAA), Islet Cell-Ab (ICA), glutamic acid decarboxylase-Ab (GADA), protein tyrosine phosphatase-Ab (IA2), Zinc Transporter 8-Ab (ZnT8), Anti-gliadin-Ab (IgA+IgG) (AGA), Anti-transglutaminase-Ab (IgA+IgG) (Anti-tTG), Anti-parietal cell-Ab (APCA), Intrinsic Factor-Ab (IF), Rheumatoid factor (RF), Anti Ovarian Antibodies (AOA). Serum cortisol, fasting plasma glucose levels were measured. The presence of Addisons disease and the onset of Type 1 DM was not determined among Graves disease patients. None of the patients with Graves disease and in the healthy control group had 21-OH-antibodies detected. The frequency of 21-OH-Ab was 4.2% in APS type 3 (p=0.07) and 91.6% in APS type 2, 4 (p0.001). The prevalence of diabetes-associated autoantibodies was 20.2% among Gravess disease patients against 8.75% in healthy subjects control group (p0.05); OR 2.64; 95% CI 1.056.66 and 30.2% in APS of adults (DM 1 negative group) (p=0.18). The prevalence of APCA-markers of autoimmune gastritis was 31.9% in Gravess disease, 48.3% in APS 24 types (p=0.01); OR 1.99; 95% CI 1.183.51, and 12.5% in control group (p0.01); OR 3.28; 95% CI 1.497.24. There were no significant differences in the frequency of occurrence of IF-Ab and RF-Ab in the groups. The frequency of AGA and ATA was 28.7% in Graves disease, 36.2% in APS types 24 (p=0.3), 10% in the control group ((р0.01); OR 3.63; 95% CI 1.548.54. Graves disease patients with risk of developing APS type 3 (positive diabetes-associated and other autoantibodies) had relatives with autoimmune diseases in 57.5% of cases (p=0.05); OR 2.18; 95% CI 1.034.63. Graves disease patients are at high risk for future development of APS 3 type, especially those with inheritance for autoimmune diseases. Screening for the immunological markers, pathognomonic for coexisting autoimmune diseases in such patients with Graves disease, as well as in patients with APS type 3, should be done regularly.

Prevalence of diabetes-associated autoantibodies among patients presenting with type 2 diabetes and related metabolic differences

BackgroundTo explores the prevalence of autoantibodies (zinc transporter 8 autoantibodies (ZnT8A), antibodies to insulin (IAAs), glutamic acid decarboxylase autoantibody (GAD65)), the relation of the type of positive autoantibody and the number of positive autoantibodies with the glycemic and lipid profile of the patients with LADA (Latent Autoimmune Diabetes in Adults) and compares it to the metabolic profile of patients presenting with type 2 diabetes (T2DM). Methods263 patients with T2DM were recruited for this cross-sectional study in Tehran, Iran. Data from patients included complete medical history, GAD65, ZnT8A, IAA and routine metabolic laboratory workup. Assay for autoantibodies were conducted using ELISA kits. The association between autoantibodies and glycemic and lipid profile of patients with diabetes was assessed using univariate and multivariate regression analysis. ResultsOur study revealed that among 263 patients with T2DM, 29 (11%) cases were positive for IAAs, 9 (3.4%) for ZnT8A, and 12 (4.6%) for GAD65. Six (2.3%) of the patients had triple positive antibodies. Patients with positive results were younger, had lower body mass index (BMI), c-peptide, triglyceride, low-density lipoprotein (LDL), and higher high-density lipoprotein (HDL), HbA1c and fasting blood glucose (FBG) levels. Triple antibody positivity was significantly associated with lower levels of C-Peptide, Triglycerides, FBG, and HbA1c compared to triple negative antibodies. ConclusionPatients with LADA positive for either of the autoantibodies (GAD65, ZnT8 and IAA) presented with worse glycemic control. Measurement of these autoantibodies can assist in discrimination of these patients and help with earlier control of glycemic profile.

Molecular and clinical characteristics of monogenic diabetes mellitus in southern Chinese children with onset before 3 years of age

IntroductionA specific molecular diagnosis of monogenic diabetes mellitus (MDM) will help to predict the clinical course and guide management. This study aims to identify the causative genes implicated in Chinese...

Type 1 diabetes in Africa: an immunogenetic study in the Amhara of North-West Ethiopia

Aims/hypothesisWe aimed to characterise the immunogenic background of insulin-dependent diabetes in a resource-poor rural African community. The study was initiated because reports of low autoantibody prevalence and phenotypic differences from European-origin cases with type 1 diabetes have raised doubts as to the role of autoimmunity in this and similar populations.MethodsA study of consecutive, unselected cases of recently diagnosed, insulin-dependent diabetes (n = 236, ≤35 years) and control participants (n = 200) was carried out in the ethnic Amhara of rural North-West Ethiopia. We assessed their demographic and socioeconomic characteristics, and measured non-fasting C-peptide, diabetes-associated autoantibodies and HLA-DRB1 alleles. Leveraging genome-wide genotyping, we performed both a principal component analysis and, given the relatively modest sample size, a provisional genome-wide association study. Type 1 diabetes genetic risk scores were calculated to compare their genetic background with known European type 1 diabetes determinants.ResultsPatients presented with stunted growth and low BMI, and were insulin sensitive; only 15.3% had diabetes onset at ≤15 years. C-peptide levels were low but not absent. With clinical diabetes onset at ≤15, 16–25 and 26–35 years, 86.1%, 59.7% and 50.0% were autoantibody positive, respectively. Most had autoantibodies to GAD (GADA) as a single antibody; the prevalence of positivity for autoantibodies to IA-2 (IA-2A) and ZnT8 (ZnT8A) was low in all age groups. Principal component analysis showed that the Amhara genomes were distinct from modern European and other African genomes. HLA-DRB1*03:01 (p = 0.0014) and HLA-DRB1*04 (p = 0.0001) were positively associated with this form of diabetes, while HLA-DRB1*15 was protective (p < 0.0001). The mean type 1 diabetes genetic risk score (derived from European data) was higher in patients than control participants (p = 1.60 × 10−7). Interestingly, despite the modest sample size, autoantibody-positive patients revealed evidence of association with SNPs in the well-characterised MHC region, already known to explain half of type 1 diabetes heritability in Europeans.Conclusions/interpretationThe majority of patients with insulin-dependent diabetes in rural North-West Ethiopia have the immunogenetic characteristics of autoimmune type 1 diabetes. Phenotypic differences between type 1 diabetes in rural North-West Ethiopia and the industrialised world remain unexplained.

Human enteroviral infection impairs autophagy in clonal INS(832/13) cells and human pancreatic islet cells

Aim/hypothesisHuman enteroviral infections are suggested to be associated with type 1 diabetes. However, the mechanism by which enteroviruses can trigger disease remains unknown. The present study aims to investigate the impact of enterovirus on autophagy, a cellular process that regulates beta cell homeostasis, using the clonal beta cell line INS(832/13) and human islet cells as in vitro models.MethodsINS(832/13) cells and human islet cells were infected with a strain of echovirus 16 (E16), originally isolated from the stool of a child who developed type 1 diabetes-associated autoantibodies. Virus production and release was determined by 50% cell culture infectious dose (CCID50) assay and FACS analysis. The occurrence of autophagy, autophagosomes, lysosomes and autolysosomes was detected by western blot, baculoviral-mediated expression of microtubule-associated protein light chain 3 (LC3)II-GFP and LysoTracker Red, and quantified by Cellomics ArrayScan. Autophagy was also monitored with a Cyto-ID detection kit. Nutrient deprivation (low glucose [2.8 mmol/l]), amino acid starvation (Earle’s Balanced Salt Solution [EBSS]) and autophagy-modifying agents (rapamycin and chloroquine) were used in control experiments. Insulin secretion and the expression of autophagy-related (Atg) genes and genes involved in autophagosome–lysosome fusion were determined.ResultsE16-infected INS(832/13) cells displayed an accumulation of autophagosomes, compared with non-treated (NT) cells (grown in complete RPMI1640 containing 11.1 mmol/l glucose) (32.1 ± 1.7 vs 21.0 ± 1.2 μm2/cell; p = 0.05). This was accompanied by increased LC3II ratio both in E16-infected cells grown in low glucose (LG) (2.8 mmol/l) (0.42 ± 0.03 vs 0.11 ± 0.04 (arbitrary units [a.u.]); p < 0.0001) and grown in media containing 11.1 mmol/l glucose (0.37 ± 0.016 vs 0.05 ± 0.02 (a.u.); p < 0.0001). Additionally, p62 accumulated in cells after E16 infection when grown in LG (1.23 ± 0.31 vs 0.36 ± 0.12 (a.u.); p = 0.012) and grown in media containing 11.1 mmol/l glucose (1.79 ± 0.39 vs 0.66 ± 0.15 (a.u.); p = 0.0078). mRNA levels of genes involved in autophagosome formation and autophagosome–lysosome fusion remained unchanged in E16-infected cells, except Atg7, which was significantly increased when autophagy was induced by E16 infection, in combination with LG (1.48 ± 0.08-fold; p = 0.02) and at 11.1 mmol/l glucose (1.26 ± 0.2-fold; p = 0.001), compared with NT controls. Moreover, autophagosomes accumulated in E16-infected cells to the same extent as when cells were treated with the lysosomal inhibitor, chloroquine, clearly indicating that autophagosome turnover was blocked. Upon infection, there was an increased viral titre in the cell culture supernatant and a marked reduction in glucose-stimulated insulin secretion (112.9 ± 24.4 vs 209.8 ± 24.4 ng [mg protein]–1 h–1; p = 0.006), compared with uninfected controls, but cellular viability remained unaffected. Importantly, and in agreement with the observations for INS(832/13) cells, E16 infection impaired autophagic flux in primary human islet cells (46.5 ± 1.6 vs 34.4 ± 2.1 μm2/cell; p = 0.01).Conclusions/interpretationEnteroviruses disrupt beta cell autophagy by impairing the later stages of the autophagic pathway, without influencing expression of key genes involved in core autophagy machinery. This results in increased viral replication, non-lytic viral spread and accumulation of autophagic structures, all of which may contribute to beta cell demise and type 1 diabetes.Graphical abstract

Saudi children with celiac disease: are they at risk of developing type-1 diabetes mellitus?

Objectives Patients with type-1 diabetes mellitus (T1DM) and celiac disease (CeD) share the same genetic susceptibility alleles. The diabetes-associated autoantibodies (DAA) may be detected in CeD patients. The aim of this study is to describe the prevalence of DAA in children with CeD. Methods This is a cross-sectional study of children with CeD. The CeD patients were divided into two groups; group 1 (n=23) included patients with isolated CeD and group 2 included patients with combined T1DM and CeD. The study was conducted at King Abdulaziz University Hospital (KAUH) in 2012-2014. DAA, including glutamic acid decarboxylase antibodies (GADA) and protein tyrosine phosphatase-2 antibodies (IA-2), were measured by enzyme-linked immunosorbent assay (ELISA) in both groups. Clinical, demographic, and laboratory data were collected from the patients' medical charts. Results DAA were determined in 23 patients in group-1 and 18 patients in group-2. Group-1 comprised 43.5% males and 56.5% females; the mean age was 15±3.7 years (with a range of 5-18 years). The prevalence of GADA and IA-2 was 69.6 and 4%, respectively. Group-2 comprised 55.6% males and 44.4% females; the mean age was 15.1±2.8 years (with a range of 7-18 years). The prevalence of GADA and IA-2 was 66.7 and 22.2%, respectively. No significant differences were found between both groups in the prevalence of GADA (p=1.0) or IA-2 (p=0.15). Conclusions Saudi children with CeD have higher prevalence of GADA than reported in a number of other Western studies. Long-term follow-up data is required before recommending routine screening for DAA.

114-OR: T1DM in the Chronically Undernourished: Rural Ethiopia

T1DM results from the interaction of genetic and environmental factors; the classical phenotype has been based largely on people of European background. However, Africa is a continent of enormous genetic diversity and extreme environmental conditions; do these differences have an impact on the T1DM phenotype? A consecutive series of recently diagnosed insulin-dependent diabetic subjects (n=236, ≤35 years) and controls (n=200), were recruited from the ethnic Amhara of rural NW Ethiopia. We assessed their demographic and socio-economic characteristics, measured non-fasting C-peptide, diabetes-associated autoantibodies, and HLA-DRB1 alleles. With genome-wide genotyping we performed principal component analysis (PCA) and a genome-wide association study (GWAS), and calculated a T1DM genetic risk scores (GRS) to compare their genetic background with known European T1DM determinants. Patients presented with low BMI, stunted growth, and were insulin sensitive; only 15.3% had diabetes onset ≤15 years. C-peptide levels were low but not absent (P=0.03). With clinical diabetes onset at ≤15, 16-25, and 26-35 years, 86.1%, 59.7% and 50.0% were autoantibody positive, respectively. Most had GADA as a single antibody; the prevalence of IA-2A and ZnT8A was low in all age groups. PCA showed that the Amhara genomes falls between those of ancestral European and ancestral African genomes. HLA-DRB1*03:01 and HLA-DRB1*04 were positively associated with diabetes while HLA-DRB1*15 was protective (P&amp;lt;0.0008 for each). The mean T1DM GRS (derived from European data) was higher in patients than controls (P=1.50x10-6). Autoantibody positive patients showed suggestive GWAS significance (P&amp;lt;5x10-6) with SNPs in the MHC region known to explain half of the T1DM heritability in Europeans. Thus, insulin-dependent diabetes in rural Ethiopia does have the immunogenetic characteristics of T1DM. The phenotypic differences between T1DM in rural Ethiopia and the industrialized world could be due, at least in part, to chronic undernourishment. Disclosure E.R. Trimble: None. S.A. Balcha: None. A.G. Demisse: None. D.L. Cousminer: None. R. Mishra: Employee; Self; GlaxoSmithKline plc. B.F. Voight: None. K. Lorenz: None. T. Vartak: None. S.T. Jerram: None. K.M. Hodge: None. S. Schwartz: Advisory Panel; Self; Intarcia Therapeutics, Janssen Pharmaceuticals, Inc. Speaker’s Bureau; Self; Boehringer Ingelheim Pharmaceuticals, Inc., Janssen Pharmaceuticals, Inc., Lilly Diabetes, Merck &amp; Co., Inc., Salix Pharmaceuticals. A. Holmes: None. A. Gamper: Stock/Shareholder; Self; GlaxoSmithKline plc., Unilever. H.F. Wilson: None. A.J. Williams: None. R.D. Leslie: None. S.F. Grant: None. D.I.W. Phillips: None. Funding American Diabetes Association (1-17-PDF-077 to D.L.C.); Association of Physicians of Great Britain and Ireland; National Institutes of Health (1K99HD099330-01, R01DK085212); Diabetes UK

Fungal Dysbiosis and Intestinal Inflammation in Children With Beta-Cell Autoimmunity.

Although gut bacterial dysbiosis is recognized as a regulator of beta-cell autoimmunity, no data is available on fungal dysbiosis in the children at the risk of type 1 diabetes (T1D). We hypothesized that the co-occurrence of fungal and bacterial dysbiosis contributes to the intestinal inflammation and autoimmune destruction of insulin-producing beta-cells in T1D. Fecal and blood samples were collected from 26 children tested positive for at least one diabetes-associated autoantibody (IAA, GADA, IA-2A or ICA) and matched autoantibody-negative children with HLA-conferred susceptibility to T1D (matched for HLA-DQB1 haplotype, age, gender and early childhood nutrition). Bacterial 16S and fungal ITS2 sequencing, and analyses of the markers of intestinal inflammation, namely fecal human beta-defensin-2 (HBD2), calprotectin and secretory total IgA, were performed. Anti-Saccharomyces cerevisiae antibodies (ASCA) and circulating cytokines, IFNG, IL-17 and IL-22, were studied. After these analyses, the children were followed for development of clinical T1D (median 8 years and 8 months). Nine autoantibody positive children were diagnosed with T1D, whereas none of the autoantibody negative children developed T1D during the follow-up. Fungal dysbiosis, characterized by high abundance of fecal Saccharomyces and Candida, was found in the progressors, i.e., children with beta-cell autoimmunity who during the follow-up progressed to clinical T1D. These children showed also bacterial dysbiosis, i.e., increased Bacteroidales and Clostridiales ratio, which was, however, found also in the non-progressors, and is thus a common nominator in the children with beta-cell autoimmunity. Furthermore, the progressors showed markers of intestinal inflammation detected as increased levels of fecal HBD2 and ASCA IgG to fungal antigens. We conclude that the fungal and bacterial dysbiosis, and intestinal inflammation are associated with the development of T1D in children with beta-cell autoimmunity.

Consumption of differently processed milk products in infancy and early childhood and the risk of islet autoimmunity.

Several prospective studies have shown an association between cows' milk consumption and the risk of islet autoimmunity and/or type 1 diabetes. We wanted to study whether processing of milk plays a role. A population-based birth cohort of 6081 children with HLA-DQB1-conferred risk to type 1 diabetes was followed until the age of 15 years. We included 5545 children in the analyses. Food records were completed at the ages of 3 and 6 months and 1, 2, 3, 4 and 6 years, and diabetes-associated autoantibodies were measured at 3-12-month intervals. For milk products in the food composition database, we used conventional and processing-based classifications. We analysed the data using a joint model for longitudinal and time-to-event data. By the age of 6 years, islet autoimmunity developed in 246 children. Consumption of all cows' milk products together (energy-adjusted hazard ratio 1·06; 95 % CI 1·02, 1·11; P = 0·003), non-fermented milk products (1·06; 95 % CI 1·01, 1·10; P = 0·011) and fermented milk products (1·35; 95 % CI 1·10, 1·67; P = 0·005) was associated with an increased risk of islet autoimmunity. The early milk consumption was not associated with the risk beyond 6 years. We observed no clear differences based on milk homogenisation and heat treatment. Our results are consistent with the previous studies, which indicate that high milk consumption may cause islet autoimmunity in children at increased genetic risk. The study did not identify any specific type of milk processing that would clearly stand out as a sole risk factor apart from other milk products.

Serum 25-hydroxyvitamin D concentration in childhood and risk of islet autoimmunity and type 1 diabetes: the TRIGR nested case\u2013control ancillary study

Aims/hypothesisOur aim was to study the association between serum 25-hydroxyvitamin D (25OHD) concentration and islet autoimmunity and type 1 diabetes in children with an increased genetic risk of type 1 diabetes.MethodsSerum samples for 25OHD measurements were obtained in the Trial to Reduce IDDM in the Genetically at Risk (TRIGR) ancillary study (Divia) from children in 15 countries. Case children (n = 244) were defined as having positivity for at least two out of four diabetes-associated autoantibodies measured at any one sample. For each case child, two control children were selected matched for country and date of birth (±1 year) (n = 488). Of the case children, 144 developed type 1 diabetes. Serum 25OHD was measured repeatedly in infancy and childhood and was compared according to age at the first seroconversion (at 6, 12 and 18 months prior to and at seroconversion) and calendar age (0, 6, 12 and 18 months).ResultsIn children with islet autoimmunity, mean serum 25OHD concentration was lower 18 months prior to the age of first seroconversion of the case children compared with the control children (57.7 vs 64.8 nmol/l, p = 0.007). In children with type 1 diabetes (n = 144), mean serum 25OHD concentration was lower 18 months prior to the age of the first seroconversion (58.0 vs 65.0 nmol/l, p = 0.018) and at the calendar age of 12 months (70.1 vs 75.9 nmol/l, p = 0.031) than in their control counterparts. Analyses were adjusted for month of sample collection, human leucocyte antigen genotype, maternal type 1 diabetes and sex.Conclusions/interpretationThe results suggest that early postnatal vitamin D may confer protection against the development of type 1 diabetes.Trial registrationClinicalTrials.gov NCT00179777

Glutamic Acid Decarboxylase Autoantibody Detection by Electrochemiluminescence Assay Identifies Latent Autoimmune Diabetes in Adults with Poor Islet Function.

BackgroundThe detection of glutamic acid decarboxylase 65 (GAD65) autoantibodies is essential for the prediction and diagnosis of latent autoimmune diabetes in adults (LADA). The aim of the current study was to compare a newly developed electrochemiluminescence (ECL)-GAD65 antibody assay with the established radiobinding assay, and to explore whether the new assay could be used to define LADA more precisely.MethodsSerum samples were harvested from 141 patients with LADA, 95 with type 1 diabetes mellitus, and 99 with type 2 diabetes mellitus, and tested for GAD65 autoantibodies using both the radiobinding assay and ECL assay. A glutamic acid decarboxylase antibodies (GADA) competition assay was also performed to assess antibody affinity. Furthermore, the clinical features of these patients were compared.ResultsEighty-eight out of 141 serum samples (62.4%) from LADA patients were GAD65 antibody-positive by ECL assay. Compared with ECL-GAD65 antibody-negative patients, ECL-GAD65 antibody-positive patients were leaner (P<0.0001), had poorer β-cell function (P<0.05), and were more likely to have other diabetes-associated autoantibodies. The β-cell function of ECL-GAD65 antibody-positive patients was similar to that of type 1 diabetes mellitus patients, whereas ECL-GAD65 antibody-negative patients were more similar to type 2 diabetes mellitus patients.ConclusionPatients with ECL-GAD65 antibody-negative share a similar phenotype with type 2 diabetes mellitus patients, whereas patients with ECL-GAD65 antibody-positive resemble those with type 1 diabetes mellitus. Thus, the detection of GADA using ECL may help to identify the subtype of LADA.

Insulin and glucose homeostasis in childhood cancer survivors treated with abdominal radiation: A pilot study

Background Childhood cancer survivors exposed to abdominal radiation (abdRT) are at increased risk for both insulin-dependent and non-insulin-dependent diabetes. We sought to clarify the pathophysiology of diabetes after abdRT by performing dynamic studies of insulin and glucose and testing for type 1 diabetes-associated autoantibodies. Procedure Cross-sectional analysis of 2-year childhood cancer survivors treated with abdRT at age ≤21 years who underwent oral glucose tolerance testing and assessment of diabetes-related autoantibodies from December 2014 to September 2016. Prevalence of insulin/glucose derangements, indices of insulin sensitivity/secretion (homeostatic model assessment of insulin resistance [HOMA-IR], whole-body insulin sensitivity, insulinogenic index), autoantibody positivity, and treatment/demographic factors associated with adverse metabolic outcomes were assessed. Results Among 40 participants previously exposed to abdRT (57.5% male; median age at cancer diagnosis, 3.3 years [range, 0.5-20.1]; median age at study 14.3 years [range, 8.3-49.8]; none with obesity), 9 (22.5%) had glucose derangements (n = 4 with impaired fasting glucose [≥100 mg/dL]; n = 4 with impaired glucose tolerance [2-hour glucose 140-199 mg/dL]; n = 1 with previously unrecognized diabetes [2-hour glucose ≥200 mg/dL]). Three of the four individuals with impaired fasting glucose also had insulin resistance, as measured by HOMA-IR; an additional four subjects with normal glucose tolerance were insulin resistant. The subject with diabetes had normal HOMA-IR. No participant had absolute insulinopenia or >1 positive diabetes-related autoantibody. Conclusions This study suggests that radiation-induced damage to the insulin-producing β-cells is an unlikely explanation for the early derangements in glucose metabolism observed after abdRT. Research into alternative pathways leading to diabetes after abdRT is needed.

A Joint Modeling Approach for Childhood Meat, Fish and Egg Consumption and the Risk of Advanced Islet Autoimmunity

Several dietary factors have been suspected to play a role in the development of advanced islet autoimmunity (IA) and/or type 1 diabetes (T1D), but the evidence is fragmentary. A prospective population-based cohort of 6081 Finnish newborn infants with HLA-DQB1-conferred susceptibility to T1D was followed up to 15 years of age. Diabetes-associated autoantibodies and diet were assessed at 3- to 12-month intervals. We aimed to study the association between consumption of selected foods and the development of advanced IA longitudinally with Cox regression models (CRM), basic joint models (JM) and joint latent class mixed models (JLCMM). The associations of these foods to T1D risk were also studied to investigate consistency between alternative endpoints. The JM showed a marginal association between meat consumption and advanced IA: the hazard ratio adjusted for selected confounding factors was 1.06 (95% CI: 1.00, 1.12). The JLCMM identified two classes in the consumption trajectories of fish and a marginal protective association for high consumers compared to low consumers: the adjusted hazard ratio was 0.68 (0.44, 1.05). Similar findings were obtained for T1D risk with adjusted hazard ratios of 1.13 (1.02, 1.24) for meat and 0.45 (0.23, 0.86) for fish consumption. Estimates from the CRMs were closer to unity and CIs were narrower compared to the JMs. Findings indicate that intake of meat might be directly and fish inversely associated with the development of advanced IA and T1D, and that disease hazards in longitudinal nutritional epidemiology are more appropriately modeled by joint models than with naive approaches.

SUN-122 Latent Autoimmune Diabetes in Adults Presenting in a Geriatric Patient with Autoimmune Hypothyroidism

Objective We describe a case of a geriatric patient with autoimmune thyroid disease who at the age of 87 presented with Latent Autoimmune Diabetes in Adults (LADA) Case An 87-year-old Caucasian man with a history of HTN, HL, extensive CVD including CABG at age 39, multiple TIA/CVA’s, macular degeneration with legal blindness, hypothyroidism and tobacco dependence was referred to endocrine clinic for worsening diabetes. Two years prior to consultation, the patient had been diagnosed with diabetes based on a fasting blood glucose level of 156mg/dL (75-120 mg/dL) and an HbA1C of 6.7%. Patient was counseled on lifestyle modifications and started on metformin. Due to occasional episodes of hypoglycemia, with a repeat HbA1C of 6.4%, metformin was discontinued. Three months later, the patient presented with polyuria/polydipsia and unintentional weight loss, HbA1c 12.5%. The patient was started on a DDP-4 inhibitor and weight based insulin detemir and referred to endocrine clinic. At the time of encounter, the patient continued to report symptomatic hyperglycemia, but denied symptoms of stiff-man syndrome. He also denied prior hospitalizations for hyperglycemia or DKA and any family history of DM, thyroid or autoimmune diseases. Blood sugars at home were 300-400’s mg/dL. Physical exam was notable for a thin man (BMI 20). Blood tests included GAD65 autoantibody > 25,000 u/ml (0-5 u/ml), repeated and confirmed, insulin autoantibodies <5 uU/ml (<5 uU/ml) and negative anti-pancreatic islet cell antibodies (<1:1). Additional tests included anti-thyroglobulin >2250.0 IU/ml (0.0-0.9 IU/ml), TPO 272 IU/ml (0-34 IU/ml) and tissue transglutaminase IgA < 2 (0-3). The patient was diagnosed with LADA; oral antihyperglycemic agents were held and weight based mealtime insulin started. Four months later, a repeat HbA1c improved to 6.7%, however due to postprandial hypoglycemia, the patient stopped all insulin. Fasting blood labs were notable for plasma glucose 211 mg/dl with a preserved C-peptide 2.5ng/ml (1.1-4.4 ng/ml). Patient was advised to resume only the long acting insulin and to continue checking his blood sugars. Hypoglycemia resolved. Conclusion LADA is a subset of type 1 diabetes mellitus and is defined by adult age at diagnosis, the presence of diabetes-associated autoantibodies, and non-insulin requiring within the first 6 months of diagnosis. LADA is more prevalent in younger adults with a mean age of onset of 33.4 years and is a rare cause of diabetes in the elderly with the oldest reported case in a 94-year-old patient. Suspicion for LADA should be heightened among patients with a prior history of autoimmune disease, with Hashimoto’s thyroiditis being the most commonly associated. We report a case of a geriatric patient who based on his physical exam and known autoimmune thyroid disease prompted evaluation for LADA. Early identification can help direct timely therapies and improve glycemic control.

Analysis of diabetes-associated autoantibodies in children and adolescents with autoimmune thyroid diseases.

Background Zinc transporter 8 autoantibodies (ZnT8Abs) together with glutamic acid decarboxylase autoantibodies (GADAbs), insulinoma antigen 2 autoantibodies (IA-2Abs) and insulin autoantibodies (IAbs) are markers of type 1 diabetes mellitus (T1DM). We studied the prevalence of ZnT8Ab in children with autoimmune thyroid diseases (AITDs) to assess the association of AITDs and T1DM at the serological level. Methods The study groups consisted of 44 children with Graves' disease (GD), 65 children with Hashimoto's thyroiditis (HT), 199 children with T1DM with or without AITDs and 58 control children. ZnT8Ab, GADAb, IA-2Ab, IAb, 21-hydroxylase autoantibodies (21-OHAbs) and acetylcholine receptor autoantibodies (AChRAbs) were measured. Results ZnT8Abs were found in 4/44 (9.1%) patients with GD, and 4/44 (9.1%) patients with GD were positive for GADAb. Of the 65 HT patients, six (9.2%) were positive for ZnT8Ab, while four (6.2%) were positive for GADAb. In the T1DM group, 128/199 (64%) of the patients were positive for ZnT8Ab, 133/199 (67%) for GADAb and 109/199 (55%) for IA-2Ab. One GD patient and one HT patient were positive for all the four diabetes-associated autoantibodies. Two HT patients were positive for three diabetes autoantibodies. Two GD (4.5%) and five HT (7.7%) patients were positive for 21-OHAb only. None of the patients had AChRAb. In the control group, 2/58 (3.4%) were positive for GADAb and 2/58 (3.4%) were positive for ZnT8Ab. Conclusions Diabetes-associated autoantibodies including ZnT8Ab were found in children and adolescents with GD and HT.

Concentration of diabetes-associated autoantibodies against islet autoantigens (IA-2A, GADA, IAA), levels of basal and postprandial glycemia, and secretory state of basal and stimulated C-peptide in the preclinical period of type 1 diabetes development in children and adolescents as immunological, metabolic and hormonal predictors of the clinical onset of the disease

Materials and methods. Based on clinical and immunological studies, in this study, we present data on the establishment of mechanisms that are responsible for the development of early and late pre-clinical stages of the type 1 diabetes (T1D), obtained by studying diabetes-associated autoantibodies (DAAb) and the levels of basal and postprandial glycemia, and C-peptide secretion at the preclinical stage of T1D development in children and adolescents. Results. As a result we were able to form a group of marker-positive children with a genetic predisposition and an increased predicted risk of developing the diease. A total of 474 practically healthy normoglycemic children and adolescents aged 7 to 18 years were examined. An elevated titre of DAAb, mainly GADA and IA-2A was found in 94 (25.68 %) of 366 children with a genetic predisposition for at least of two determinants of DAAb, and the clinical onset of T1D manifesting in 68 (72.34 %) of them from 6 months to 15 years (30.9 ± 3.2 months). The formula of combined occurrence and values of simultaneously elevated titres of DAAb against islet autoantigens, namely, IA-2A + GADA, which is a predictor of the duration of the preclinical stage of T1D, was determined. Conclusions. It was established that the early preclinical development of T1D in DAAb + children was characterized by the presence of dysglycemia in the form of elevated glycemia 2 hours after the glucose tolerance test and a steady decrease in the secretion of stimulated C-peptide; additionally, dysglycemia was jointed as impaired fasting glycemia, and there was a decrease in both basal and stimulated secretions of C peptide, indicating the depletion of the potential of pancreatic beta-cells. Key words: type 1 diabetes (T1D), children and adolescents, diabetes-associated autoantibodies (DAAb), autoantibodies against glutamic acid decarboxylase (GADA), autoantibodies against tyrosine phosphatase (IA-2A), basal and postprandial glycemia, basal and stimulated C-peptide. For citation: Tronko MD, Mankovskyi BM, Popova VV, Zak KP. Concentration of diabetes-associated autoantibodies against islet autoantigens (IA-2A, GADA, IAA), levels of basal and postprandial glycemia, and secretory state of basal and stimulated C-peptide in the preclinical period of type 1 diabetes development in children and adolescents as immunological, metabolic and hormonal predictors of the clinical onset of the disease. Journal of the National Academy of Medical Sciences of Ukraine. 2019;25(3):285–95

Identification of autoimmune type 1 diabetes and multiple organ-specific autoantibodies in adult-onset non-insulin-requiring diabetes in China: A population-based multicentre nationwide survey.

To investigate the prevalence of adult-onset autoimmune diabetes (ADM) and predisposition to autoimmune diseases by quantifying serum organ-specific autoantibodies in people with phenotype of type 2 diabetes (T2D). We included a nationally representative sample of 46 239 adults aged ≥20 years from 14 provinces, of whom 4671 had diabetes, plus 1000 control subjects with normal glucose tolerance (NGT). Participants were screened centrally for autoantibodies to glutamic acid decarboxylase (GAD), islet antigen 2 (IA2) and zinc transporter isoform-8 (Znt8) and were defined as having ADM where positive for these antibodies. We then assayed thyroid peroxidase (TPO), tissue transglutaminase (tTG) and 21-hydroxylase (21-OH) autoantibodies in randomly selected participants with ADM and in age-matched, sex-matched and non-ADM controls with T2D plus controls with NGT. Post-normalization, the standardized prevalence rate of ADM was 6.0% (95% confidence interval [CI] 5.3-6.8) in initially non-insulin-requiring participants with ADM, corresponding to six million adults in China, in whom adjusted antibody positivity was: TPO autoantibodies 16.3% (95% CI 10.8-21.8), tTG autoantibodies 2.1% (95% CI 0.0-4.2), and 21-OH autoantibodies 1.8% (95% CI -0.2 to 3.8). Those participants with ADM who were GAD autoantibody-positive had high risk of TPO autoantibody positivity (odds ratio [OR] 2.39, P = 0.0031) and tTG autoantibody positivity (OR 6.98, P = 0.027), while those positive for IA2 autoantibodies had a high risk of tTG autoantibody positivity (OR 19.05, P = 0.001). A proportion of people with phenotype of T2D in China have ADM, with diabetes-associated autoantibodies, and may be at risk of developing other organ-specific autoimmune diseases; therefore, it may be clinically relevant to consider screening such Chinese populations.

No evidence of the role of early chemical exposure in the development of \u03b2-cell autoimmunity

Exposure to environmental chemicals can modulate the developing immune system, but its role in the pathogenesis of type 1 diabetes is largely unexplored. Our objective was to study the levels of circulating concentrations of environmental pollutants during the first years of life and their associations with the later risk of diabetes-predictive autoantibodies. From two birth-cohort studies including newborn infants with HLA-conferred susceptibility to type 1 diabetes (FINDIA and DIABIMMUNE), we identified case children with at least one biochemical diabetes-associated autoantibody (n = 30–40) and from one to four autoantibody-negative controls per each case child matched for age, gender, diabetes-related HLA-risk, delivery hospital, and, in FINDIA, also dietary intervention group. Plasma levels of 13 persistent organic pollutants and 14 per- and polyfluorinated substances were analyzed in cord blood and plasma samples taken at the age of 12 and 48 months. Both breastfeeding and the geographical living environment showed association with circulating concentrations of some of the chemicals. Breastfeeding-adjusted conditional logistic regression model showed association between decreased plasma HBC concentration at 12-month-old children and the appearance of diabetes-associated autoantibodies (HR, 0.989; 95% Cl, 0.978–1.000; P = 0.048). No association was found between the plasma chemical levels and the development of clinical type 1 diabetes. Our results do not support the view that exposure to the studied environmental chemicals during fetal life or early childhood is a significant risk factor for later development of β-cell autoimmunity and type 1 diabetes.