A gluten-free diet lowers NKG2D and ligand expression in BALB/c and non-obese diabetic (NOD) mice.

The interplay between diet and immune parameters which could affect type 1 diabetes (T1D) pathogenesis is not sufficiently clarified. Intestinal up-regulation of the activating receptor natural killer group 2D (NKG2D) (CD314) and its ligands is a hallmark of coeliac disease. However, the direct effect of gluten on NKG2D expression is not known. We studied, by fluorescence activated cell sorter (lymphoid tissues) and reverse transcription-quantitative polymerase chain reaction (intestine and pancreatic islets), if a gluten-free diet (GF diet) from 4 weeks of age or a gluten-free diet introduced in breeding pairs (SGF diet), induced changes in NKG2D expression on DX5(+) (CD49b) natural killer (NK) cells, CD8(+) T cells and in intestinal and islet levels of NKG2D and ligands in BALB/c and non-obese diabetic (NOD) mice. Gluten-free NOD mice had lower insulitis (P < 0·0001); reduced expression of NKG2D on DX5(+) NK cells in spleen and auricular lymph nodes (P < 0·05); and on CD8(+) T cells in pancreas-associated lymph nodes (P = 0·04). Moreover, the level of CD71 on DX5(+) NK cells and CD8(+) T cells (P < 0·005) was markedly reduced. GF and SGF mice had reduced expression of NKG2D and DX5 mRNA in intestine (P < 0·05). Differences in intestinal mRNA expression were found in mice at 8, 13 and 20 weeks. Intestinal expression of NKG2D ligands was reduced in SGF mice with lower expression of all ligands. In isolated islets, a SGF diet induced a higher expression of specific NKG2D ligands. Our data show that a gluten-free diet reduces the level of NKG2D and the expression of NKG2D ligands. These immunological changes may contribute to the lower T1D incidence associated with a gluten-free diet.

Early life treatment with vancomycin propagates Akkermansia muciniphila and reduces diabetes incidence in the NOD mouse.

AIMS/HYPOTHESIS: Increasing evidence suggests that environmental factors changing the normal colonisation pattern in the gut strongly influence the risk of developing autoimmune diabetes. The aim of this study was to investigate, both during infancy and adulthood, whether treatment with vancomycin, a glycopeptide antibiotic specifically directed against Gram-positive bacteria, could influence immune homeostasis and the development of diabetic symptoms in the NOD mouse model for diabetes. METHODS: Accordingly, one group of mice received vancomycin from birth until weaning (day 28), while another group received vancomycin from 8 weeks of age until onset of diabetes. Pyrosequencing of the gut microbiota and flow cytometry of intestinal immune cells was used to investigate the effect of vancomycin treatment. RESULTS: At the end of the study, the cumulative diabetes incidence was found to be significantly lower for the neonatally treated group compared with the untreated group, whereas the insulitis score and blood glucose levels were significantly lower for the mice treated as adults compared with the other groups. Mucosal inflammation was investigated by intracellular cytokine staining of the small intestinal lymphocytes, which displayed an increase in cluster of differentiation (CD)4(+) T cells producing pro-inflammatory cytokines in the neonatally treated mice. Furthermore, bacteriological examination of the gut microbiota composition by pyrosequencing revealed that vancomycin depleted many major genera of Gram-positive and Gram-negative microbes while, interestingly, one single species, Akkermansia muciniphila, became dominant. CONCLUSIONS/INTERPRETATION: The early postnatal period is a critical time for microbial protection from type 1 diabetes and it is suggested that the mucolytic bacterium A. muciniphila plays a protective role in autoimmune diabetes development, particularly during infancy.

Association between age, IL-10, IFNγ, stimulated C-peptide and disease progression in children with newly diagnosed Type 1 diabetes.

AIMS: The relation of disease progression and age, serum interleukin 10 (IL-10) and interferon gamma (IFNγ) and their genetic correlates were studied in paediatric patients with newly diagnosed Type 1 diabetes. METHODS: Two hundred and twenty-seven patients from the Hvidoere Study Group were classified in four different progression groups as assessed by change in stimulated C-peptide from 1 to 6 months. CA repeat variants of the IL-10 and IFNγ gene were genotyped and serum levels of IL-10 and IFNγ were measured at 1, 6 and 12 months. RESULTS: IL-10 decreased (P < 0.001) by 7.7% (1 month), 10.4% (6 months) and 8.6% (12 months) per year increase in age of child, while a twofold higher C-peptide concentration at 1 month (p = 0.06), 6 months (P = 0.0003) and 12 months (P = 0.02) was associated with 9.7%, 18.6% and 9.7% lower IL-10 levels, independent of each other. IL-10 concentrations did not associate with the disease progression groups. By contrast, IFNγ concentrations differed between the four progression groups at 6 and 12 months (P = 0.02 and P = 0.01, respectively); patients with rapid progressing disease had the highest levels at both time points. Distribution of IL-10 and IFNγ genotypes was equal among patients from the progression groups. CONCLUSION: IL-10 serum levels associate inversely with age and C-peptide. As age and C-peptide also associate, a triangular association is proposed. Genetic influence on IL-10 production seems to be masked by distinct disease mechanisms. Increased serum IFNγ concentrations associate with rapid disease progression. Functional genetic variants do not associate with a single progression pattern group, implying that disease processes override genetically predisposed cytokine production.

Glucose activation of islets of Langerhans up-regulates Toll-like receptor 5: possible mechanism of protection.

Toll-like receptors are pattern-recognition receptors of the innate immune system that are activated during viral, bacterial or other infections, as well as during disease progression of type 1 and type 2 diabetes. Toll-like receptor 5 (TLR-5) specifically recognizes bacterial infection through binding of flagellin from pathogenic bacteria such as Salmonella and Listeria species. We have found that the expression of TLR5 is up-regulated by glucose activation of isolated islets of Langerhans, in contrast to other investigated TLRs (TLR-2, -3, -4, -6 and -9. Stimulation of islets with 10 mm glucose increased the levels of TLR5 mRNA 10-fold (P=0·03) and the TLR-5 protein levels twofold (P=0·04). Furthermore, the protein level of downstream signalling molecule myeloid differentiation primary response gene 88 (MyD88) increased 1·6-fold (P=0·01). Activation of TLR-5 in islets lead to a marked reduction of both stimulated and basal secretion of insulin, as well as an increase in production of nitric oxide, proinflammatory cytokines, anti-inflammatory heat-shock protein and major histocompatibility complex (MHC) class I transporter. We observe no effects of TLR-5 activation on islet survival. We suggest that this regulation by TLR-5 might be beneficial during serious infection such as sepsis by limiting the activity of beta cells during peaks of insulin demand to counteract beta cell damage.

Birthweight and the risk of childhood-onset type 1 diabetes: a meta-analysis of observational studies using individual patient data.

AIMS/HYPOTHESIS: We investigated whether children who are heavier at birth have an increased risk of type 1 diabetes. METHODS: Relevant studies published before February 2009 were identified from literature searches using MEDLINE, Web of Science and EMBASE. Authors of all studies containing relevant data were contacted and asked to provide individual patient data or conduct pre-specified analyses. Risk estimates of type 1 diabetes by category of birthweight were calculated for each study, before and after adjustment for potential confounders.Meta-analysis techniques were then used to derive combined ORs and investigate heterogeneity between studies. RESULTS: Data were available for 29 predominantly European studies (five cohort, 24 case-control studies), including 12,807 cases of type 1 diabetes. Overall, studies consistently demonstrated that children with birthweight from 3.5 to 4 kg had an increased risk of diabetes of 6% (OR 1.06 [95% CI 1.01-1.11]; p=0.02) and children with birthweight over 4 kg had an increased risk of 10% (OR 1.10 [95% CI 1.04-1.19]; p=0.003), compared with children weighing 3.0 to 3.5 kg at birth. This corresponded to a linear increase in diabetes risk of 3% per 500 g increase in birthweight (OR 1.03 [95% CI 1.00-1.06]; p=0.03). Adjustments for potential confounders such as gestational age, maternal age, birth order, Caesarean section, breastfeeding and maternal diabetes had little effect on these findings. CONCLUSIONS/INTERPRETATION: Children who are heavier at birth have a significant and consistent, but relatively small increase in risk of type 1 diabetes.

Association of adiponectin, interleukin (IL)-1ra, inducible protein 10, IL-6 and number of islet autoantibodies with progression patterns of type 1 diabetes the first year after diagnosis.

The progression of type 1 diabetes after diagnosis is poorly understood. Our aim was to assess the relation of disease progression of juvenile-onset type 1 diabetes, determined by preserved beta cell function the first year after diagnosis, with systemic cytokine concentrations and number of autoantibodies. Juvenile patients (n = 227) had a meal-stimulated C-peptide test 1 and 6 months after diagnosis. On the basis of the C-peptide course for the duration of 1-6 months, four progression groups were defined: patients with persistently low beta cell function ('stable-low'), rapid progressers, slow progressers and remitters. Serum concentrations of adiponectin, interleukin (IL)-1ra, inducible protein 10 (IP-10), IL-6 and glutamic acid decarboxylase (GAD), IA-2A and islet-cell antibodies (ICA) were measured at 1, 6 and 12 months. We found that adiponectin concentrations at 1 month predicted disease progression at 6 months (P = 0·04). Patients with low adiponectin had a higher probability of becoming remitters than rapid progressers, odds ratio 3·1 (1·3-7·6). At 6 and 12 months, adiponectin differed significantly between the groups, with highest concentrations among stable-low and rapid progressers patients (P = 0·03 and P = 0·006). IL-1ra, IP-10 and IL-6 did not differ between the groups at any time-point. The number of autoantibodies differed significantly between the groups at 1 month (P = 0·04), where rapid progressers had the largest number. There was no difference between the groups in human leucocyte antigen-associated risk. We define progression patterns distinguishing patients diagnosed with low beta cell function from those with rapid decline, slow decline or actual increase in beta cell function, pointing to different mechanisms of disease progression. We find that adiponectin concentration at 1 month predicts, and at 6 and 12 months associates with, distinct progression patterns.

The glycolipid sulfatide protects insulin-producing cells against cytokine-induced apoptosis, a possible role in diabetes.

AIMS/HYPOTHESIS: Cytokine-induced apoptosis is recognised as a major cause of the decline in ß-cell mass that ultimately leads to type 1 diabetes mellitus. Interleukin-1ß, interferon-γ and tumour necrosis factor-α in conjunction initiate a series of events that lead to ß-cell apoptosis; important among these is NO production. The glycosphingolipid sulfatide is present in ß-cells in the secretory granules in varying amounts and is secreted together with insulin. We now investigate whether sulfatide is able to protect insulin-producing cells against the pro-apoptotic effect of interleukin-1ß, interferon-γ and tumour necrosis factor-α. METHODS: INS-1E cells and genuine rat islets were incubated for 24 h exposed to interleukin-1ß, interferon-γ and tumour necrosis factor-α with or without sulfatide. The production of NO was monitored and the number of apoptotic cells was determined using terminal deoxynucleotidyl transferase-mediated dUTP Nick-End labelling and caspase-3/7 activity assays. In addition, the amount of iNOS mRNA was determined using real-time quantitative polymerase chain reaction. RESULTS: Cytokine-induced apoptosis was reduced to 27% of cytokine-treated controls with 30 µmol/L sulfatide treatment (p < 0.01). Likewise, sulfatide in concentrations of 3-30 µmol/L decreased NO production in a dose-dependent manner to 19-40% of cytokine-treated controls (overall p = 0.0007). The level of iNOS mRNA after cytokine exposure was reduced to 55% of cytokine-treated controls with 30 µmol/L of sulfatide. CONCLUSIONS/INTERPRETATION: In the present study, we report the ability of sulfatide to significantly reduce apoptosis, cellular leakage and NO production in insulin-producing cells. Data suggest this is not due to induction of ß-cell rest. Our findings indicate a possible implication for sulfatide in the pathogenesis of diabetes.

Dietary gluten reduces the number of intestinal regulatory T cells in mice.

It is well established that gluten-free diet reduces the incidence of type 1 diabetes mellitus (T1D) in non-obese diabetic (NOD) mice, though the mechanism is not known. However, regulatory T cells (Treg) are likely to play an important role. Also, it is known that dietary gluten induces an intestinal increase in the bacterium Lactococcus garvieae, but the importance of this phenomenon for T1D development is doubtful. Our hypothesis is that gluten is responsible for mediating its effect on T1D through the influence on Treg development independent of gluten-induced Lactococci. Four groups of female NOD and BALB/c mice of 3 week old were fed either a gluten-free diet or a standard diet. Lactococcus garvieae or saline water was administered per oral to one of each dietary group. Spleen and Peyer's patches were sampled from BALB/c mice for flow cytometric monitoring of IL-10 and Treg. NOD mice were diagnosed diabetic with blood glucose level >12 mmol/l. Dietary gluten significantly decreased the occurrence of Tregs by 10-15% (P < 0.05) in mice compared with those fed a standard diet. These results and the diabetes incidence were independent of the gluten-induced bacterial factor Lactococci. The prevalence of Treg was 5- to 10-fold more abundant in the Peyer's patches than in the spleen (P < 0.001). In conclusion, dietary gluten has a significant negative quantitative impact on the generation of Treg in mice, independent of gluten-induced Lactococcus garvieae, and Treg are far more abundant in Peyer's patches than in the spleen.

Reduced frequency of blood group Lewis a-b- in female Type 1 diabetes patients.

AIMS: To examine a disputed association between the Lewis(a(-)b(-)) phenotype and Type 1 diabetes (T1D). METHODS: Lewis red blood cell phenotyping was performed for 97 T1D White patients and 100 control subjects using monoclonal antibodies. Two historical cohorts were also included as a control population. RESULTS: T1D patients had a lower frequency (4.1%) of Lewis(a(-)b(-)) blood group compared with simultaneously tested healthy control subjects (10.0%) and the historical control group (11.1%, P = 0.02). Male T1D patients showed a Lewis(a(-)b(-)) frequency of 8.0%, which was similar to both matched healthy male donors (9.8%) and historical (9.5%) male control subjects. Unexpectedly, none of the female T1D patients displayed Lewis(a(-)b(-)) phenotype, vs. 10.3% and 10.8% of female control subjects (P = 0.039 and 0.017). CONCLUSIONS: The Lewis(a(-)b(-)) phenotype occurs less frequently in T1D compared with healthy control subjects with a strong female gender bias.

Differential responsiveness to interferon-alpha in beta-cells and non-beta cells.

Interferon-alpha (IFN-alpha) is important in the innate immune defense, particularly in viral infections. IFN-alpha induces 2',5'A synthetase, the products of which, 2',5'-oligoadenine nucleotides, activate mRNA degrading enzymes. IFN-alpha is the first detectable cytokine in the insulitis lesion seen in recent-onset IDDM, and insulin promoter directed expression of IFN-alpha in transgenic mice leads to development of IDDM. Here, we demonstrate that IFN-alpha induces 2',5'A synthetase activity only in insulin-producing betaTC3 cells and in isolated single rat beta-cells but not in alphaTC3 cells or in isolated rat non-beta-cells. The increased responsiveness of beta-cells but not non-beta-cells to IFN-alpha with the ensuing activation of the mRNA-degrading 2',5'A synthetase system suggests why only the beta-cells are destroyed in the diabetogenic process.

Linear correlation between the total islet mass and the volume-weighted mean islet volume.

To understand the dynamics of islet population, especially during conditions with growth of the total islet mass, it is important to have reliable estimators of parameters describing the quantitative appearance of the islet population. We describe a stereological estimator of the volume-weighted mean islet volume based on unbiased assumption-free stereological principles. The volume-weighted mean islet volume is the mean islet volume if the islets are weighted (sampled) proportional to their volume. This method allows simultaneously unbiased estimation of the total islet mass. With use of this method, 22 male Sprague-Dawley rats within the age span of 34-102 days old were investigated. We found a linear correlation (P < 0.001) between total islet mass and the volume-weighted mean islet volume. The results support models demonstrating that the physiological growth of the total islet mass in the period studied is totally or mainly caused by proportional growth of existing islets. The functional meaning of the volume-weighted mean islet volume is discussed, and previous methods to study the mean islet volume and islet number are critically evaluated. We propose the volume-weighted mean islet volume to be a biologically useful parameter when describing the mean volume of the pancreatic islets and investigating the differences between experimental groups.

Glucagon-like peptide I and glucose-dependent insulinotropic polypeptide stimulate Ca2+-induced secretion in rat alpha-cells by a protein kinase A-mediated mechanism.

High-resolution capacitance measurements were used to explore the effects of the gut hormones GLP-I(7-36) amide [glucagon-like peptide I(7-36) amide] and GIP (glucose-dependent insulinotropic polypeptide) on Ca2+-dependent exocytosis in glucagon-secreting rat pancreatic alpha-cells. Both peptides produced a greater than threefold potentiation of secretion evoked by voltage-clamp depolarizations, an effect that was associated with an approximately 35% increase of the Ca2+ current. The stimulatory actions of GLP-I(7-36) amide and GIP were mimicked by forskolin and antagonized by the protein kinase A (PKA)-inhibitor Rp-8-Br-cAMPS. The islet hormone somatostatin inhibited the stimulatory action of GLP-I(7-36) amide and GIP via a cyclic AMP-independent mechanism, whereas insulin had no effect on exocytosis. These data suggest that the alpha-cells are equipped with receptors for GLP-I and GIP and that these peptides, in addition to their well-established insulinotropic capacity, also stimulate glucagon secretion. We propose that the reported inhibitory action of GLP-I on glucagon secretion is accounted for by a paracrine mechanism (e.g., mediated by stimulated release of somatostatin that in turn suppresses exocytosis in the alpha-cell).

Efficient gene transfer to dispersed human pancreatic islet cells in vitro using adenovirus-polylysine/DNA complexes or polycationic liposomes.

The establishment of gene delivery systems that result in efficient transfection of the pancreatic beta-cells may generate an important tool for the study of IDDM and may also represent one critical step toward a clinical application of gene transfer for the prevention or early treatment of the disease. Using the reporter gene vectors pCAT and pCMV beta-gal, we have investigated the efficiency of transfection mediated by calcium phosphate precipitation, the monocationic liposome Lipofectin, the polycationic liposome Lipofectamine, and adenovirus-polylysine (AdpL) DNA complexes in human, mouse, rat, and fetal porcine islet cells. In all species studied, calcium phosphate-mediated transfection resulted in lower chloramphenicol acetyl transferase (CAT) activities than the other methods. Intact human, mouse, and rat islets were poorly transfected by Lipofectin, Lipofectamine, and AdpL. When dispersed by trypsin treatment, however, human, mouse, rat, and fetal pig islect cells were efficiently transfected by Lipofectamine. Moreover, transfection of dispersed human and mouse islet cells using AdpL, also resulted in high CAT activities. The percentage of cells staining positively for beta-galactosidase after transfection with Lipofectamine was 49% for mouse, 56% for rat, and 57% for dispersed human islet cells. Transfection of human islet cells using AdpL, however, yielded 70% beta-gal-positive cells. Fluorescence-activated cell sorting-purified rat islet alpha- and beta-cells were transfected with similar efficiency using Lipofectamine. CAT expression in human islet cells transfected with either Lipofectamine or AdpL reached a peak value after 5-7 days, followed by a gradual decline. It is concluded that transfection with AdpL or Lipofectamine are both efficient means to achieve transient expression of gene constructs in human and mouse islet cells, while for rat and fetal porcine islet cells, Lipofectamine is the most efficient of the agents investigated in this study.

Dependence of antigen expression on functional state of beta-cells.

Antigen expression corresponding to anti-islet cell surface monoclonal antibodies IC2 and A2B5 was studied. IC2 is a rat-rat hybridoma autoantibody produced from the BB rat; among islet cells, IC2 is beta-cell specific. A2B5 is an anti-ganglioside antibody described as labeling beta-cells. Islets of Langerhans from Lewis rats were isolated and cultured for 18 h in RPMI-1640 with five different glucose concentrations (2.2, 3.3, 5.5, 11.1, and 18.3 mM). In some experiments, islets were precultured for 2 or 3 days. After isolation of islet cells and antibody labeling, the percent of IC2+ beta-cells in the different groups increased from 33.3, 34.5, 40.9, and 57.2 to 58.6% (P less than 10(-6). For A2B5, the percent of labeled islet cells increased from 37.4, 41.8, 46.7, and 53.8 to 56.2% (P less than 10(-4). Thus, increasing glucose concentration leading to higher beta-cell activity implies an increase in antigen expression. Neither A2B5 nor IC2 reacts with insulin, as shown by absorption experiments and immune electron microscopy of binding sites. Electron microscopy of IC2-gold-labeled islet cells substantiated the beta-cell specificity of IC2. In conclusion, expression of the corresponding antigens to IC2 and A2B5 depends on the functional state of the beta-cells; because this has been shown to be an important factor in the development of insulin-dependent diabetes, our findings may be of potential pathogenetic interest.

Differential expression of glutamic acid decarboxylase in rat and human islets.

The GABA synthesizing enzyme GAD is a prominent islet cell autoantigen in type I diabetes. The two forms of GAD (GAD64 and GAD67) are encoded by different genes in both rats and humans. By in situ hybridization analysis of rat and human pancreases, expression of both genes was detected in rat islets, whereas only GAD64 mRNA was detected in human islets. Immunocytochemical analysis of rat and human pancreatic sections or isolated islets with antibodies to GAD64 and GAD67 in combination with antibodies to insulin, glucagon, or SRIF confirmed that a GAD64 and GAD67 expression were beta-cell specific in rat islets. In contrast, only GAD64 was detected in human islets and was, in addition to beta-cells, also surprisingly localized to some alpha-cells, delta-cells, and PP-cells. In long-term (4 wk) monolayer cultures of newborn rat islet cells, GAD64 expression remained beta-cell specific as observed in vivo, whereas GAD67 was localized not only to the beta-cells but also in the alpha-cells and delta-cells. A small but distinct fraction of GAD positive cells in these monolayer cultures did not accumulate GABA immunoreactivity, which may indicate cellular heterogeneity with respect to GABA catabolism or GAD enzyme activity. In a rat insulinoma cell line (NHI-6F) producing both glucagon and insulin depending on the culture conditions, GAD64 expression was detected only in cultures in which the insulin producing phenotype dominated. In conclusion, these data demonstrate that the two GAD isoforms are differentially expressed in rat and human islets but also that the expression differs according to culture conditions. These findings emphasize the need to consider both the species and culture conditions of islets.

Adrenaline stimulates glucagon secretion in pancreatic A-cells by increasing the Ca2+ current and the number of granules close to the L-type Ca2+ channels.

We have monitored electrical activity, voltage-gated Ca2+ currents, and exocytosis in single rat glucagon-secreting pancreatic A-cells. The A-cells were electrically excitable and generated spontaneous Na+- and Ca2+-dependent action potentials. Under basal conditions, exocytosis was tightly linked to Ca2+ influx through omega-conotoxin-GVIA-sensitive (N-type) Ca2+ channels. Stimulation of the A-cells with adrenaline (via beta-adrenergic receptors) or forskolin produced a greater than fourfold PKA-dependent potentiation of depolarization-evoked exocytosis. This enhancement of exocytosis was due to a 50% enhancement of Ca2+ influx through L-type Ca2+ channels, an effect that accounted for <30% of the total stimulatory action. The remaining 70% of the stimulation was attributable to an acceleration of granule mobilization resulting in a fivefold increase in the number of readily releasable granules near the L-type Ca2+ channels.

Previous maternal abortion, longer gestation, and younger maternal age decrease the risk of type 1 diabetes among male offspring.

OBJECTIVE: To identify possible influences and interactions of perinatal determinants in the subsequent development of type 1 diabetes. RESEARCH DESIGN AND METHODS: The data were obtained from children born in Denmark during the periods 1978-1982 and 1984-1986 and admitted to a Danish hospital with newly diagnosed type 1 diabetes between 1978 and 1995; 857 patients fulfilled the criteria. The study was conducted by combining and analyzing two national registries: the National Patient Registry and the Medical Birth Registry. For each diabetic child, two control children were randomly selected, matched by sex, time, and district of delivery. RESULTS: By multivariate logistic regression analysis, the following significant determinants were identified. Male offspring showed decreased risk when born of mothers who had had one or more abortions (odds ratio [OR] 0.66 [95% CI 0.48-0.92]) and with long duration of gestation (linearly with OR 0.91 per week [0.85-0.99]), while increased risk was found for high maternal age (linearly with OR 1.03 per year [1.00-1.06]). Female offspring showed no such association. No significant differences between diabetic patients and control subjects were found with respect to paternal age, maternal parity, placental weight or any of the birth size parameters, or interventions and complications during delivery. CONCLUSIONS: The findings show that perinatal determinants may influence the risk of subsequent development of type 1 diabetes in a sex-specific manner.

Perinatal determinants among children who later develop IDDM.

OBJECTIVE: The aim of this study was to investigate whether children who develop insulin-dependent diabetes mellitus (IDDM) differ in some aspects from a matched control group at the time of birth. RESEARCH DESIGN AND METHODS: We studied all children who were born in Denmark during the period 1973-1977 and admitted to a Danish hospital with a diagnosis of IDDM during 1978-1989. The study was conducted by combining two nationwide registries, The National Patient Registry and The Birth Registry. RESULTS: The criteria were fulfilled by 837 children. Data regarding the age of the parents, the number of previous pregnancies of the mother, the month of birth, and the birth weight and length of the children who developed IDDM were compared with the data of an age- and sex-matched control group of 837 children without IDDM. We did not detect any significant differences between the two groups with respect to the parameters studied. CONCLUSIONS: No differences in perinatal determinants could be demonstrated among Danish children who develop IDDM compared with children without diabetes.

A model for the study of autoimmune diseases applied to pemphigus: transplants of human oral mucosa to athymic nude mice binds pemphigus antibodies in vivo.

The present paper describes a new in vivo method to study the action of pemphigus antibodies against human tissue. Oral mucosal biopsies from healthy donors were transplanted to athymic nude mice, which, a week later, were injected with serum from pemphigus patients. From 1 to 5 days after the injection the epithelial transplants were removed and preparations were studied by immunofluorescence microscopy. Pemphigus antibodies were demonstrated in preparations from each of 23 mice which had received pemphigus serum, but in none of 6 which had received control serum. Transplants from about 2/3 of the experimental mice showed intercellular edema of the basal layers of the epithelium and in transplants from 3 mice supra-basilar splitting of the epithelium was found. None of these changes was seen in the control mice. Passive transfer of human serum or lymphocytes to nude mice transplanted with human tissue may be use in future studies of autoimmune diseases, including pemphigus.