Time-Resolved Autoantibody Profiling Facilitates Stratification of Preclinical Type 1 Diabetes in Children.

Progression to clinical type 1 diabetes varies among children who develop ß-cell autoantibodies. Differences in autoantibody patterns could relate to disease progression and etiology. Here we modeled complex longitudinal autoantibody profiles by using a novel wavelet-based algorithm. We identified clusters of similar profiles associated with various types of progression among 600 children from The Environmental Determinants of Diabetes in the Young (TEDDY) birth cohort study; these children developed persistent insulin autoantibodies (IAA), GAD autoantibodies (GADA), insulinoma-associated antigen 2 autoantibodies (IA-2A), or a combination of these, and they were followed up prospectively at 3- to 6-month intervals (median follow-up 6.5 years). Children who developed multiple autoantibody types (n = 370) were clustered, and progression from seroconversion to clinical diabetes within 5 years ranged between clusters from 6% (95% CI 0, 17.4) to 84% (59.2, 93.6). Children who seroconverted early in life (median age <2 years) and developed IAA and IA-2A that were stable-positive on follow-up had the highest risk of diabetes, and this risk was unaffected by GADA status. Clusters of children who lacked stable-positive GADA responses contained more boys and lower frequencies of the HLA-DR3 allele. Our novel algorithm allows refined grouping of ß-cell autoantibody-positive children who distinctly progressed to clinical type 1 diabetes, and it provides new opportunities in searching for etiological factors and elucidating complex disease mechanisms.

Rapid decline in insulin antibodies and glutamic acid decarboxylase autoantibodies with ibrutinib therapy of chronic lymphocytic leukaemia.

WHAT IS KNOWN AND OBJECTIVE: Ibrutinib is inhibiting the Bruton's tyrosine kinase (BTK), thereby influencing B-cell development. We describe an unexpected side effect of ibrutinib in two patients with chronic lymphocytic leukaemia concerning the vigorous decrease of two different diabetes-associated antibodies. CASE DESCRIPTION: Two weeks after onset of ibrutinib therapy, patient A frequently noticed symptoms of hypoglycaemia such as dizziness and blurred vision. Blood glucose declined to 35-40 mg/dL. He had to lower his insulin dose step by step. High levels of insulin antibodies which had developed during insulin therapy were detected. Seven weeks after start of ibrutinib, his insulin antibodies level had dropped by 54.6%. Patient B had a 54.1% decrease in his glutamic acid decarboxylase autoantibodies level after 7 weeks. WHAT IS NEW AND CONCLUSION: The inhibitory effect of ibrutinib on the levels of insulin antibodies and glutamic acid decarboxylase autoantibodies is a novel finding and may have implications for diabetes care.

Histochemistry and immunolocalisation of glucokinin in antidiabetic plants used in traditional Mexican medicine.

Mexico is a megadiverse country that has 3,600 to 4,000 species of medicinal plants, of which approximately 800 are used to treat conditions related to diabetes mellitus (DM). DM is a chronic degenerative disease of energy metabolism that exists as two types: type 1 (DM1) and type 2 (DM2). DM is considered a public health problem that affects 7% of the Mexican population older than 20 years. DM is clinically controlled with hypoglycaemic drugs, alpha-glucosidase inhibitors, insulin secretion stimulants or the direct application of insulin. The hypoglycaemic effectiveness of specific molecules has been determined only for some medicinal plants in Mexico used to treat DM2. The presence of molecules called glucokinins, wich are similar to animal insulin molecules, has been reported in some plant species; glucokinins act as both growth factors and regulators of glucose metabolism in plants. Therefore, we hypothesized that the hypoglycaemic effectiveness of some of the popularly used species for the control of DM could be due to the presence of glucokinin, as reported for Bauhinia variegata. The goal of this work was to use histochemistry to detect, the accumulation of protein that is immunocytochemically compatible with glucokinin in slide sections of hypoglycaemic species used as remedies for DM2. The top fourteen most used medicinal plants in Mexico were selected for study via microscopic sections. Proteins were histochemically detected using naphthol blue black and Johansen's quadruple stain, and the immunocytochemical correspondence of the proteins with glucokinin was investigated using an insulin antibody. All species studied reacted positively to proteins and glucokinin in the same structures. The presence of glucokinin in these structures and the corresponding hypoglycaemic effects are discussed in the contex of the actions of other compounds.

Early prediction of autoimmune (type 1) diabetes.

Underlying type 1 diabetes is a genetic aetiology dominated by the influence of specific HLA haplotypes involving primarily the class II DR-DQ region. In genetically predisposed children with the DR4-DQ8 haplotype, exogenous factors, yet to be identified, are thought to trigger an autoimmune reaction against insulin, signalled by insulin autoantibodies as the first autoantibody to appear. In children with the DR3-DQ2 haplotype, the triggering reaction is primarily against GAD signalled by GAD autoantibodies (GADA) as the first-appearing autoantibody. The incidence rate of insulin autoantibodies as the first-appearing autoantibody peaks during the first years of life and declines thereafter. The incidence rate of GADA as the first-appearing autoantibody peaks later but does not decline. The first autoantibody may variably be followed, in an apparently non-HLA-associated pathogenesis, by a second, third or fourth autoantibody. Although not all persons with a single type of autoantibody progress to diabetes, the presence of multiple autoantibodies seems invariably to be followed by loss of functional beta cell mass and eventually by dysglycaemia and symptoms. Infiltration of mononuclear cells in and around the islets appears to be a late phenomenon appearing in the multiple-autoantibody-positive with dysglycaemia. As our understanding of the aetiology and pathogenesis of type 1 diabetes advances, the improved capability for early prediction should guide new strategies for the prevention of type 1 diabetes.

Insulin degludec does not increase antibody formation versus insulin glargine: an evaluation of phase IIIa trials.

We examined insulin antibody formation in patients with type 1 (T1D) or type 2 diabetes (T2D) treated with once-daily insulin degludec (IDeg) or insulin glargine (IGlar) to evaluate the impact of antibody formation on efficacy and safety. Insulin antibodies were measured using subtraction radioimmunoassays in six phase IIIa clinical trials using IDeg (n = 2250) and IGlar (n = 1184). Spearman's correlation coefficient was used to evaluate associations between cross-reacting antibodies and change from baseline glycated haemoglobin (HbA1c) and insulin dose. IDeg- and IGlar-specific antibodies remained low [<1% bound/total radioactivity (B/T)] and with low levels of antibodies cross-reacting with human insulin in patients with T1D (<20% B/T) and T2D (<6% B/T). Spearman's correlation coefficients between insulin antibody levels and change in HbA1c or insulin dose were low in both treatment groups. No clinically meaningful differences in adverse event (AE) rates were observed in patients with >10% B/T or without an absolute increase in antibodies cross-reacting with human insulin. IDeg treatment resulted in few immunogenic responses in patients with T1D and T2D; antibody formation was not associated with change in HbA1c, insulin dose or rates of AEs.

[B cells from streptozotocin-induced mouse diabetic model inhibit insulin secretion of MIN-6 cells and promote production of insulin autoantibody].

OBJECTIVE: To explore the role of B cells in the progression of mouse diabetes induced by streptozotocin (STZ). METHODS: The ICR mouse diabetic model was induced by low-dose STZ injection. Radioimmunoassay was performed to examine the serum levels of insulin, and ELISA was conducted to detect insulin autoantibody (IAA). B cells from STZ-treated mice and control group were sorted by CD19 magnetic activated cell sorting (MACS), and cell purity was verified by flow cytometry. The PBS-treated MIN-6 cells were used as blank control group (group A); the isolated normal mouse B cells were incubated with MIN-6 cells as group B; B cells isolated from normal mice were pre-stimulated with 20 µg/mL lipopolysaccharides (LPS), then were incubated with MIN-6 cells, as group C; and B cells isolated from STZ-treated mice were incubated with MIN-6 cells, as group D. The mRNA and protein levels of insulin were detected by quantitative real-time PCR (qRT-PCR) and radioimmunoassay, respectively. The levels of IAA and transforming growth factor ß(TGF-ß) were detected by ELISA. RESULTS: Compared with group A, STZ-treated mice showed reduced body mass and serum insulin, but increased blood glucose and IAA levels. Flow cytometry indicated that the proportion of CD19(+) B cells were 98%. Compared with group A or B, group C or D presented with decreased mRNA and protein levels of insulin in MIN-6 cells, simultaneously, increased expressions of IAA and TGF-ß. CONCLUSION: B cells isolated from STZ-treated mice promotes the production of IAA and inhibits the secretion of insulin in MIN-6 cells.

Predictors of Progression From the Appearance of Islet Autoantibodies to Early Childhood Diabetes: The Environmental Determinants of Diabetes in the Young (TEDDY).

OBJECTIVE: While it is known that there is progression to diabetes in <10 years in 70% of children with two or more islet autoantibodies, predictors of the progression to diabetes are only partially defined. RESEARCH DESIGN AND METHODS: The Environmental Determinants of Diabetes in the Young (TEDDY) study has observed 8,503 children who were at increased genetic risk for autoimmune diabetes. Insulin autoantibodies (IAAs), GAD65 autoantibodies (GADAs), and insulinoma-associated protein 2 autoantibodies (IA-2As) were measured every 3 months until 4 years of age and every 6 months thereafter; if results were positive, the autoantibodies were measured every 3 months. RESULTS: Life table analysis revealed that the cumulative incidence of diabetes by 5 years since the appearance of the first autoantibody differed significantly by the number of positive autoantibodies (47%, 36%, and 11%, respectively, in those with three autoantibodies, two autoantibodies, and one autoantibody, P < 0.001). In time-varying survival models adjusted for first-degree relative status, number of autoantibodies, age at first persistent confirmed autoantibodies, and HLA genotypes, higher mean IAA and IA-2A levels were associated with an increased risk of type 1 diabetes in children who were persistently autoantibody positive (IAAs: hazard ratio [HR] 8.1 [95% CI 4.6-14.2]; IA-2A: HR 7.4 [95% CI 4.3-12.6]; P < 0.0001]). The mean GADA level did not significantly affect the risk of diabetes. CONCLUSIONS: In the TEDDY study, children who have progressed to diabetes usually expressed two or more autoantibodies. Higher IAA and IA-2A levels, but not GADA levels, increased the risk of diabetes in those children who were persistently autoantibody positive.

Electrochemiluminescence assays for insulin and glutamic acid decarboxylase autoantibodies improve prediction of type 1 diabetes risk.

We recently developed new electrochemiluminescence (ECL) insulin autoantibody (IAA) and glutamic acid decarboxylase 65 autoantibody (GADA) assays that discriminate high-affinity, high-risk diabetes-specific autoantibodies from low-affinity, low-risk islet autoantibodies (iAbs) detected by radioassay (RAD). Here, we report a further validation of the ECL-IAA and -GADA assays in 3,484 TrialNet study participants. The ECL assay and RAD were congruent in those with prediabetes and in subjects with multiple autoantibodies, but only 24% (P<0.0001) of single RAD-IAA-positive and 46% (P<0.0001) of single RAD-GADA-positive were confirmed by the ECL-IAA and -GADA assays, respectively. During a follow-up (mean, 2.4 years), 51% of RAD-IAA-positive and 63% of RAD-GADA-positive subjects not confirmed by ECL became iAb negative, compared with only 17% of RAD-IAA-positive (P<0.0001) and 15% of RAD-GADA-positive (P<0.0001) subjects confirmed by ECL assays. Among subjects with multiple iAbs, diabetes-free survival was significantly shorter if IAA or GADA was positive by ECL and negative by RAD than if IAA or GADA was negative by ECL and positive by RAD (P<0.019 and P<0.0001, respectively). Both positive and negative predictive values in terms of progression to type 1 diabetes mellitus were superior for ECL-IAA and ECL-GADA, compared with RADs. The prevalence of the high-risk human leukocyte antigen-DR3/4, DQB1*0302 genotype was significantly higher in subjects with RAD-IAA or RAD-GADA confirmed by ECL. In conclusion, both ECL-IAA and -GADA are more disease-specific and better able to predict the risk of progression to type 1 diabetes mellitus than the current standard RADs.

Disease progression among 446 children with newly diagnosed type 1 diabetes located in Scandinavia, Europe, and North America during the last 27 yr.

OBJECTIVE: To clarify whether the rate of decline in stimulated C-peptide (SCP) from 2 to 15 months after diagnosis has changed over an interval of 27 yr. RESEARCH DESIGN AND METHODS: The rate of decline in SCP levels at 1, 2, 3, 6, 9, 12, and 15 months after diagnosis was compared in four paediatric cohorts from Scandinavian and European countries including 446 children with new onset type 1 diabetes (T1D, 1982-2004). Findings were evaluated against 78 children (2004-2009) from the TrialNet studies. RESULTS: The mean rate of decline [%/month (±SEM)] in SCP for a 10-yr-old child was 7.7%/month (±1.5) in the 1982-1985 Cohort, 6.3%/month (±1.7) in the 1995-1998 Cohort, 7.8%/month (±0.7) in the 1999-2000 Cohort, and 10.7%/month (±0.9) in the latest 2004-2005 Cohort (p = 0.05). Including the TrialNet Cohort with a rate of decline in SCP of 10.0%/month (±0.9) the differences between the cohorts are still significant (p = 0.039). The rate of decline in SCP was negatively associated with age (p < 0.0001), insulin antibodies (IA) (p = 0.003), and glutamic acid decarboxylase-65 (GAD65A) (p = 0.03) initially with no statistically significant effect of body mass index (BMI) Z-score at 3 months. Also, at 3 months the time around partial remission, the effect of age on SCP was significantly greater in children ≤5 yr compared with older children (p ≤ 0.0001). CONCLUSIONS: During the past 27 yr, initial C-peptide as well as the rate of C-peptide decline seem to have increased. The rate of decline was affected significantly by age, GAD65A, and IA, but not BMI Z-score or initial C-peptide.

Insulin immuno-neutralization in fed chickens: effects on liver and muscle transcriptome.

Chickens mimic an insulin-resistance state by exhibiting several peculiarities with regard to plasma glucose level and its control by insulin. To gain insight into the role of insulin in the control of chicken transcriptome, liver and leg muscle transcriptomes were compared in fed controls and "diabetic" chickens, at 5 h after insulin immuno-neutralization, using 20.7K-chicken oligo-microarrays. At a level of false discovery rate <0.01, 1,573 and 1,225 signals were significantly modified by insulin privation in liver and muscle, respectively. Microarray data agreed reasonably well with qRT-PCR and some protein level measurements. Differentially expressed mRNAs with human ID were classified using Biorag analysis and Ingenuity Pathway Analysis. Multiple metabolic pathways, structural proteins, transporters and proteins of intracellular trafficking, major signaling pathways, and elements of the transcriptional control machinery were largely represented in both tissues. At least 42 mRNAs have already been associated with diabetes, insulin resistance, obesity, energy expenditure, or identified as sensors of metabolism in mice or humans. The contribution of the pathways presently identified to chicken physiology (particularly those not yet related to insulin) needs to be evaluated in future studies. Other challenges include the characterization of "unknown" mRNAs and the identification of the steps or networks, which disturbed tissue transcriptome so extensively, quickly after the turning off of the insulin signal. In conclusion, pleiotropic effects of insulin in chickens are further evidenced; major pathways controlled by insulin in mammals have been conserved despite the presence of unique features of insulin signaling in chicken muscle.

Insulin autoantibodies with high affinity to the bovine milk protein alpha casein.

Insulin autoantibodies (IAA) can appear in children within months of introducing solid foods to the diet and before clinical type 1 diabetes. The aim of this study was to determine whether infant dietary antigens could be immunizing agents of IAA. To this end, IAA binding to [(125) I]insulin was competed with food preparations and extracts of foods encountered in the infant diet (milk formulas, bovine milk, wheat flour, fowl meal). Bovine milk powder extracts inhibited IAA-positive samples from six of 53 children (age 0·3-14·0 years) participating in German prospective cohorts. Inhibition in these sera ranged from 23 to 100%. Competition was abolished when hydrolyzed milk powder was used. Competition with protein components of bovine milk found that two of the six milk-reactive sera were inhibited strongly by alpha- and beta-casein; none were inhibited by the milk proteins bovine serum albumin or lactoglobulins. The two casein-reactive sera had high affinity to alpha-casein (1·7×10(9) ; 3·1×10(9) l/mol), and lesser affinity to beta-casein (4·0×10(8) ; 7·0×10(7) l/mol) and insulin (2·6×10(8) ; 1·6×10(8) l/mol). No children with milk-reactive IAA developed autoantibodies to other islet autoantigens or diabetes (median follow-up 9·8 years). These results suggest that autoimmunity to insulin can occur infrequently via cross-reactivity to food proteins, but this form of IAA immunization does not appear to be associated with progression to diabetes.

Reduced diabetes in btk-deficient nonobese diabetic mice and restoration of diabetes with provision of an anti-insulin IgH chain transgene.

Type 1 diabetes results from T cell-mediated destruction of insulin-producing beta cells. Although elimination of B lymphocytes has proven successful at preventing disease, modulation of B cell function as a means to prevent type 1 diabetes has not been investigated. The development, fate, and function of B lymphocytes depend upon BCR signaling, which is mediated in part by Bruton's tyrosine kinase (BTK). When introduced into NOD mice, btk deficiency only modestly reduces B cell numbers, but dramatically protects against diabetes. In NOD, btk deficiency mirrors changes in B cell subsets seen in other strains, but also improves B cell-related tolerance, as indicated by failure to generate insulin autoantibodies. Introduction of an anti-insulin BCR H chain transgene restores diabetes in btk-deficient NOD mice, indicating that btk-deficient B cells are functionally capable of promoting autoimmune diabetes if they have a critical autoimmune specificity. This suggests that the disease-protective effect of btk deficiency may reflect a lack of autoreactive specificities in the B cell repertoire. Thus, signaling via BTK can be modulated to improve B cell tolerance, and prevent T cell-mediated autoimmune diabetes.

Interleukin-21 is required for the development of type 1 diabetes in NOD mice.

OBJECTIVE: Interleukin (IL)-21 is a type 1 cytokine that has been implicated in the pathogenesis of type 1 diabetes via the unique biology of the nonobese diabetic (NOD) mouse strain. The aim of this study was to investigate a causal role for IL-21 in type 1 diabetes. RESEARCH DESIGN AND METHODS: We generated IL-21R-deficient NOD mice and C57Bl/6 mice expressing IL-21 in pancreatic beta-cells, allowing the determination of the role of insufficient and excessive IL-21 signaling in type 1 diabetes. RESULTS: Deficiency in IL-21R expression renders NOD mice resistant to insulitis, production of insulin autoantibodies, and onset of type 1 diabetes. The lymphoid compartment in IL-21R-/- NOD is normal and does not contain an increased regulatory T-cell fraction or diminished effector cytokine responses. However, we observed a clear defect in autoreactive effector T-cells in IL-21R-/- NOD by transfer experiments. Conversely, overexpression of IL-21 in pancreatic beta-cells induced inflammatory cytokine and chemokines, including IL-17A, IL17F, IFN-gamma, monocyte chemoattractant protein (MCP)-1, MCP-2, and interferon-inducible protein-10 in the pancreas. The ensuing leukocytic infiltration in the islets resulted in destruction of beta-cells and spontaneous type 1 diabetes in the normally diabetes-resistant C57Bl/6 and NOD x C57Bl/6 backgrounds. CONCLUSIONS: This work provides demonstration of the essential prodiabetogenic activities of IL-21 on diverse genetic backgrounds (NOD and C57BL/6) and indicates that IL-21 blockade could be a promising strategy for interventions in human type 1 diabetes.

Antibody response to insulin in children and adolescents with newly diagnosed Type 1 diabetes.

AIMS: To compare levels of insulin antibodies in children and adolescents after initiation of insulin therapy using either insulin aspart (IAsp) or human insulin (HI) in combination with Neutral Protamine Hagedorn (NPH) insulin, and to investigate the relationships between insulin antibodies and HbA(1c) and insulin dose. METHODS: IAsp-specific antibodies (IAsp-Ab) and antibodies cross-reacting with HI and IAsp (HI-cross-Ab) were analysed by radioimmunoassay at diagnosis of diabetes and every 3-6 months for 30 months. Seventy-two patients (HI = 30, IAsp = 42) with Type 1 diabetes, aged 2-17 years were included. Data on HbA(1c), insulin dose and serious adverse events (SAEs) were collected retrospectively. RESULTS: IAsp-Ab levels remained low throughout the study. After 9 months, the level of HI-cross-Ab increased [mean (SD) HI, 48.8% (21.53); IAsp, 40.2% (17.92)] and remained elevated. Repeated measurement analysis of HI-cross-Ab levels showed no significant difference between treatments (P = 0.16). HI-cross-Ab were significantly associated with total insulin dose (U/kg) (P = 0.001) and time (P < 0.0001), but not with HbA(1c) (P = 0.24). Mean (+/- SD) HbA(1c) was similar at diagnosis (HI 9.5 +/- 1.97%; IAsp 9.6 +/- 1.62%); HbA(1c) then decreased and stabilized to about 6.0% in both groups. Few SAEs were reported, the majority being hypoglycaemic episodes. CONCLUSIONS: Treatment with IAsp and with HI was associated with an increase in HI-cross-Ab in insulin-naive children, but this did not influence treatment efficacy or safety. These results support the safe use of IAsp in children and adolescents with Type 1 diabetes.

The natural history of type 1A diabetes.

We can now predict the development of Type 1A (Immune Mediated) diabetes primarily through the determination of four biochemically characterized islet autoantibodies [insulin, GAD65, IA-2 (ICA512) and (Znt8)]. Prediction is possible because beta-cell destruction is chronically progressive and very slow in most, but not all individuals. We can also prevent type 1A diabetes in animal models and a major goal is the prevention of type 1A diabetes in man with multiple clinical trials underway.

The natural history of type 1A diabetes

We can now predict the development of Type 1A (Immune Mediated) diabetes primarily through the determination of four biochemically characterized islet autoantibodies [insulin, GAD65, IA-2 (ICA512) and (Znt8)]. Prediction is possible because beta-cell destruction is chronically progressive and very slow in most, but not all individuals. We can also prevent type 1A diabetes in animal models and a major goal is the prevention of type 1A diabetes in man with multiple clinical trials underway.

Atualmente o desenvolvimento do diabetes melito tipo 1 A( imune mediado) pode ser predito através da determinação de quatro auto-anticorpos antiilhotas [antiinsulina, anti-GAD65, anti-IA2 (ICA512) e (anti-Znt8)] caracterizados bioquimicamente. A predição dessa doença é possível devido a destruição das células-beta, não em todos os indivíduos mas na sua maioria, ser crônica e lentamente progressiva. Também é possível prevenir o DM1 A em modelos animais e o objetivo maior é a prevenção dessa doença em humanos, para os quais vários protocolos clínicos estão em andamento.

Severe hypoglycaemia in a person with insulin autoimmune syndrome accompanied by insulin receptor anomaly type B.

AIMS: A rare case of the insulin autoimmune syndrome (IAS) accompanied by insulin receptor anomaly is reported. METHODS: Antibodies to insulin and insulin receptor were determined in the patient with severe hypoglycaemia before and after the treatment with prednisolone. RESULTS: Titers of antibody to insulin and insulin receptors were 73.0% and 41.5%, respectively. Drug-induced lymphocyte stimulation tests were all negative for the suspicious drugs. Her HLA-DR was DRB1*0403/04051. Following steroid therapy, the formation of antibodies was suppressed and alleviated her symptoms. Scatchard analysis yielded findings specific to polyclonal antibodies. CONCLUSIONS: The changes in autoantibodies resulted in alleviation of the hypoglycemic symptoms as a result of steroid therapy.

Identification of insulin autoantibodies of IgA isotype that preferentially target non-human insulin.

Insulin autoantibodies (IAA) precede clinical type 1 diabetes in children. Immunization events leading to IAA are unknown. The aim of this study was to determine whether some IAA result from mucosal immunization. IgA-IAA and binding of IAA to non-human insulin were examined in selected high and low affinity IAA-positive samples and in first IAA-positive samples from children aged <2 years. High affinity IAA (>10(9)L/mol) bound strongly to human insulin and poorly to chicken insulin. In contrast, 12/13 lower affinity IAA were chicken insulin-reactive, binding equally to human and chicken insulin (n=4), or preferentially binding chicken insulin (n=8). IgA-IAA were found in association with chicken insulin-reactive IAA, and included cases where IgA-IAA predominated over IgG-IAA. Among 20 IAA-positive children aged <2 years, one had early IgA-chicken insulin-reactive IAA that were replaced by high affinity IgG-IAA. The findings suggest that some IAA can result from immunization against molecules other than human insulin at mucosal sites.