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Artificial intelligence takes center stage: exploring the capabilities and implications of ChatGPT and other AI-assisted technologies in scientific research and education In the future, public and private organizations also face the possibility of cyberattacks that may target AI models and assistants, that could use AI jailbreaking techniques to try and coax AI assistants into revealing sensitive information or acting on the attacker's behalf by biasing the behavior of the model. (c) Considering this, in incorporating AI into routine science, the primary question for each scientist is to subjectively consider where they can leverage the increased productivity that AI provides without compromising or, best of all, while enhancing their abilities and accelerating their development. gl If we accept this generalization, then, for the foreseeable future, where is AI better than humans and where are humans better than AI? Keywords: AI; ChatGPT; education; ethics; LLM; research; science EN AI ChatGPT education ethics LLM research science 923 935 13 11/03/23 20231101 NES 231101 The emergence of large language models (LLMs) and assisted artificial intelligence (AI) technologies have revolutionized the way in which we interact with technology. [Extracted from the article]

Aims/Introduction: Autoantibodies to pancreatic islet antigens identify young children at high risk of type 1 diabetes. On a background of genetic susceptibility, islet autoimmunity is thought to be driven by environmental factors, of which enteric viruses are prime candidates. We sought evidence for enteric pathology in children genetically at‐risk for type 1 diabetes followed from birth who had developed islet autoantibodies ("seroconverted"), by measuring mucosa‐associated cytokines in their sera. Materials and Methods: Sera were collected 3 monthly from birth from children with a first‐degree type 1 diabetes relative, in the Environmental Determinants of Islet Autoimmunity (ENDIA) study. Children who seroconverted were matched for sex, age, and sample availability with seronegative children. Luminex xMap technology was used to measure serum cytokines. Results: Of eight children who seroconverted, for whom serum samples were available at least 6 months before and after seroconversion, the serum concentrations of mucosa‐associated cytokines IL‐21, IL‐22, IL‐25, and IL‐10, the Th17‐related cytokines IL‐17F and IL‐23, as well as IL‐33, IFN‐γ, and IL‐4, peaked from a low baseline in seven around the time of seroconversion and in one preceding seroconversion. These changes were not detected in eight sex‐ and age‐matched seronegative controls, or in a separate cohort of 11 unmatched seronegative children. Conclusions: In a cohort of children at risk for type 1 diabetes followed from birth, a transient, systemic increase in mucosa‐associated cytokines around the time of seroconversion lends support to the view that mucosal infection, e.g., by an enteric virus, may drive the development of islet autoimmunity. [ABSTRACT FROM AUTHOR]

Aims: Islet autoantibody screening of infants and young children in the Northern Hemisphere, together with semi‐annual metabolic monitoring, is associated with a lower risk of ketoacidosis (DKA) and improved glucose control after diagnosis of clinical (stage 3) type 1 diabetes (T1D). We aimed to determine if similar benefits applied to older Australians and New Zealanders monitored less rigorously. Methods: DKA occurrence and metabolic control were compared between T1D relatives screened and monitored for T1D and unscreened individuals diagnosed in the general population, ascertained from the Australasian Diabetes Data Network. Results: Between 2005 and 2019, 17,105 relatives (mean (SD) age 15.7 (10.8) years; 52% female) were screened for autoantibodies against insulin, glutamic acid decarboxylase, and insulinoma‐associated protein 2. Of these, 652 screened positive to a single and 306 to multiple autoantibody specificities, of whom 201 and 215, respectively, underwent metabolic monitoring. Of 178 relatives diagnosed with stage 3 T1D, 9 (5%) had DKA, 7 of whom had not undertaken metabolic monitoring. The frequency of DKA in the general population was 31%. After correction for age, sex and T1D family history, the frequency of DKA in screened relatives was >80% lower than in the general population. HbA1c and insulin requirements following diagnosis were also lower in screened relatives, consistent with greater beta cell reserve. Conclusions: T1D autoantibody screening and metabolic monitoring of older children and young adults in Australia and New Zealand, by enabling pre‐clinical diagnosis when beta cell reserve is greater, confers protection from DKA. These clinical benefits support ongoing efforts to increase screening activity in the region and should facilitate the application of emerging immunotherapies. [ABSTRACT FROM AUTHOR]

Background: Children born to larger households have less allergic disease. T regulatory cell (Treg) development may be a relevant mechanism, but this has not been studied longitudinally. Objective: We aim to (i) describe how prenatal and postnatal environmental factors are associated with Treg development and (ii) investigate whether serial Treg measures predict allergic outcomes at 1 year of age. Methods: A birth cohort (n = 1074) with information on prenatal and postnatal early life factors. Both naïve Treg (nTreg) and activated Treg (aTreg) cell populations (as a proportion of CD4+ T cells) were available in 463 infants at birth (cord blood), 600 at 6 months, and 675 at 12 months. 191 infants had serial measures. Measures of allergic status at 12 months were polysensitization (sensitization to 2 or more allergens), clinically proven food allergy, atopic eczema, and atopic wheeze. Results: Infants born to larger households (3 or more residents) had higher longitudinal nTreg proportions over the first postnatal year with a mean difference (MD) of 0.67 (95% CI 0.30–1.04)%. Higher nTreg proportions at birth were associated with a reduced risk of infant allergic outcomes. Childcare attendance and breastfeeding were associated with higher longitudinal nTreg proportions (MD 0.48 (95% CI 0.08–0.80)%. Conclusion: Multiple prenatal and postnatal microbial factors are associated with nTreg and aTreg development. Larger household size was associated with higher nTreg at birth which in turn was associated with reduced allergic sensitization and disease at 12 months of age. [ABSTRACT FROM AUTHOR]

Aim: We aimed to characterize associations between diet and the gut microbiome and short chain fatty acid (SCFA) products in youth with islet autoimmunity or type 1 diabetes (IA/T1D) in comparison with controls. Research design and methods: Eighty participants (25 diagnosed with T1D, 17 with confirmed IA, 38 sibling or unrelated controls) from the Australian T1D Gut Study cohort were studied (median [IQR] age 11.7 [8.9, 14.0] years, 43% female). A Food Frequency Questionnaire characterized daily macronutrient intake over the preceding 6 months. Plasma and fecal SCFA were measured by gas chromatography; gut microbiome composition and diversity by 16S rRNA gene sequencing. Results: A 10 g increase in daily carbohydrate intake associated with higher plasma acetate in IA/T1D (adjusted estimate +5.2 (95% CI 1.1, 9.2) μmol/L p = 0.01) and controls (adjusted estimate +4.1 [95% CI 1.7, 8.5] μmol/L p = 0.04). A 5 g increase in total fat intake associated with lower plasma acetate in IA/T1D and controls. A 5% increase in noncore (junk) food intake associated with reduced richness (adjusted estimate −4.09 [95%CI –7.83, −0.35] p =.03) and evenness (−1.25 [95% CI –2.00, −0.49] p < 0.01) of the gut microbiome in IA/T1D. Fiber intake associated with community structure of the microbiome in IA/T1D. Conclusions: Modest increments in carbohydrate and fat intake associated with plasma acetate in all youth. Increased junk food intake associated with reduced diversity of the gut microbiome in IA/T1D alone. These associations with the gut microbiome in IA/T1D support future efforts to promote SCFA by using dietary interventions. [ABSTRACT FROM AUTHOR]

Background: Microbial exposures in utero and early life shape the infant microbiome, which can profoundly impact on health. Compared to the bacterial microbiome, very little is known about the virome. We set out to characterize longitudinal changes in the gut virome of healthy infants born to mothers with or without type 1 diabetes using comprehensive virome capture sequencing. Methods: Healthy infants were selected from Environmental Determinants of Islet Autoimmunity (ENDIA), a prospective cohort of Australian children with a first‐degree relative with type 1 diabetes, followed from pregnancy. Fecal specimens were collected three‐monthly in the first year of life. Results: Among 25 infants (44% born to mothers with type 1 diabetes) at least one virus was detected in 65% (65/100) of samples and 96% (24/25) of infants during the first year of life. In total, 26 genera of viruses were identified and >150 viruses were differentially abundant between the gut of infants with a mother with type 1 diabetes vs without. Positivity for any virus was associated with maternal type 1 diabetes and older infant age. Enterovirus was associated with older infant age and maternal smoking. Conclusions: We demonstrate a distinct gut virome profile in infants of mothers with type 1 diabetes, which may influence health outcomes later in life. Higher prevalence and greater number of viruses observed compared to previous studies suggests significant underrepresentation in existing virome datasets, arising most likely from less sensitive techniques used in data acquisition. [ABSTRACT FROM AUTHOR]

Background: In previous studies, deficits in regulatory T‐cell (Treg) number and function at birth have been linked with subsequent allergic disease. However, longitudinal studies that account for relevant perinatal factors are required. The aim of this study was to investigate the relationship between perinatal factors, naïve Treg (nTreg) over the first postnatal year and development of food allergy. Methods: In a birth cohort (n = 1074), the proportion of nTreg in the CD4+ T‐cell compartment was measured by flow cytometry at birth (n = 463), 6 (n = 600) and 12 (n = 675) months. IgE‐mediated food allergy was determined by food challenge at 1 year. Associations between perinatal factors (gestation, labour, sex, birth size), nTreg at each time point and food allergy at 1 year were examined by linear regression. Results: A higher proportion of nTreg at birth, larger birth size and male sex was each associated with higher nTreg in infancy. Exposure to labour, as compared to delivery by prelabour Caesarean section, was associated with a transient decrease nTreg. Infants that developed food allergy had decreased nTreg at birth, and the labour‐associated decrease in nTreg at birth was more evident among infants with subsequent food allergy. Mode of birth was not associated with risk of food allergy, and there was no evidence that nTreg at either 6 or 12 months were related to food allergy. Conclusion: The proportion of nTreg at birth is a major determinant of the proportion present throughout infancy, highlighting the importance of prenatal immune development. Exposure to the inflammatory stimulus of labour appears to reveal differences in immune function among infants at risk of food allergy. [ABSTRACT FROM AUTHOR]

Aims/hypothesis: To investigate the longitudinal relationship between the gut microbiome, circulating short chain fatty acids (SCFAs) and intestinal permeability in children with islet autoimmunity or type 1 diabetes and controls. Methods: We analyzed the gut bacterial microbiome, plasma SCFAs, small intestinal permeability and dietary intake in 47 children with islet autoimmunity or recent‐onset type 1 diabetes and in 41 unrelated or sibling controls over a median (range) of 13 (2‐34) months follow‐up. Results: Children with multiple islet autoantibodies (≥2 IA) or type 1 diabetes had gut microbiome dysbiosis. Anti‐inflammatory Prevotella and Butyricimonas genera were less abundant and these changes were not explained by differences in diet. Small intestinal permeability measured by blood lactulose:rhamnose ratio was higher in type 1 diabetes. Children with ≥2 IA who progressed to type 1 diabetes (progressors), compared to those who did not progress, had higher intestinal permeability (mean [SE] difference +5.14 [2.0], 95% confidence interval [CI] 1.21, 9.07, P =.006), lower within‐sample (alpha) microbial diversity (31.3 [11.2], 95% CI 9.3, 53.3, P =.005), and lower abundance of SCFA‐producing bacteria. Alpha diversity (observed richness) correlated with plasma acetate levels in all groups combined (regression coefficient [SE] 0.57 [0.21], 95% CI 0.15, 0.99 P =.008). Conclusions/Interpretation: Children with ≥2 IA who progress to diabetes, like those with recent‐onset diabetes, have gut microbiome dysbiosis associated with increased intestinal permeability. Interventions that expand gut microbial diversity, in particular SCFA‐producing bacteria, may have a role to decrease progression to diabetes in children at‐risk. [ABSTRACT FROM AUTHOR]

The incidence of type 1 diabetes globally has increased dramatically over the last 50 years. Proposed environmental reasons for this increase mirror the modern lifestyle. Type 1 diabetes can be viewed as part of the non- communicable disease epidemic in our modern society. Meanwhile rapidly evolving new technologies are advancing our understanding of how human microbial communities interface with the immune system and metabolism, and how the modern pro-inflammatory environment is changing these communities and contributing to the rapid rise of non-communicable disease. The majority of children who present with clinical type 1 diabetes are of school age; however 80% of children who develop type 1 diabetes by 18 years of age will have detectable islet autoantibodies by 3 years of age. The evolving concept that type 1 diabetes in many children has developmental origins has directed research questions in search of prevention back to pregnancy and early life. To this end the world's first pregnancy to early childhood cohort study in at-risk children has commenced. [ABSTRACT FROM AUTHOR]

Background We investigated whether graft produced anti-human CD2, mediated by adenovirus (Adv) transduction of pig neonatal islet cell clusters ( pNICC), would protect xenografts in a humanized mouse model from immune attack and whether such immunosuppression would remain local. Methods A mouse anti-human CD2 Ab (CD2hb11) previously generated by us was genetically engineered to produce chimeric and humanized versions. The three forms of CD2hb11 were named dilimomab (mouse), diliximab (chimeric) and dilizumab (humanized). All 3 forms of CD2hb11 Ab were tested for their ability to bind CD3+ human T cells and to inhibit a human anti-pig xenogeneic mixed lymphocyte reaction (MLR). They were administered systemically in a humanized mouse model in order to test their ability to deplete human CD3+ T cells and whether they induced a cytokine storm. An adenoviral vector expressing diliximab was generated for transduction of p NICC. Humanized mice were transplanted with either control-transduced p NICC or diliximab-transduced p NICC and human T cells within grafts and spleens were enumerated by flow cytometry. Results Dilimomab and diliximab inhibited a human anti-pig xenogeneic response but dilizumab did not. All 3 forms of CD2hb11 Ab bound human T cells in vitro though dilimomab and diliximab exhibited 300-fold higher avidity than dilizumab. All 3 anti-CD2 Abs could deplete human CD3+ T cells in vivo in a humanized mouse model without inducing upregulation of activation markers or significant release of cytokines. Humanized mice transplanted with diliximab-transduced p NICC afforded depletion of CD3+ T cells at the graft site leaving the peripheral immune system intact. Conclusions Local production of a single Ab against T cells can reduce graft infiltration at the xenograft site and may reduce the need for conventional, systemic immunosuppression. [ABSTRACT FROM AUTHOR]

Following activation by antigen, T cells enter the cell cycle in stages that can be defined with flow cytometric markers. We show that these markers include the increase of forward light scatter width (FSC-W) signal and the ratio of FSC area/peak. This change in light scatter precedes the first cell division and may reflect blast transformation. We show that the FSC-W parameter can be used, alone or in combination with other activation markers, to monitor the relative and absolute numbers of T cells responding to a proliferative stimulus. In contrast to dye dilution assays, the FSC-W method does not allow discrimination between consecutive cell divisions, but it has several advantages and could complement the dye dilution assay. Our findings also show that the routine elimination of doublets based on FSC signals may exclude proliferating T cells from the analysis. © 2011 International Society for Advancement of Cytometry [ABSTRACT FROM AUTHOR]

Immune tolerance to self-antigens is physiological. Given a repertoire of self-reactive, potentially pathogenic lymphocytes, therapeutic options to diminish autoimmune disease risk include deletion, reduced activation or increased regulation of self-reactive lymphocytes by means that mimic or promote physiological mechanisms of immunity. Vaccination with self-antigen to promote self-antigen-specific tolerance, ‘negative vaccination’, may represent the most specific and potentially safest means of averting autoimmune disease. This strategy is therapeutically effective in inbred rodent models but its translation in humans has failed to meet expectations. This failure can be attributed to the use of suboptimal dosage regimens in end-stage disease, as well as other factors. This review focuses on vaccination against self-antigen in type 1 diabetes, an autoimmune disease unique in that individuals at risk can be identified years before clinical presentation. Moreover, the spontaneously diabetic non-obese diabetic mouse, which mimics human type 1 diabetes in many ways, has provided ‘proof-of-concept’ for negative vaccination. Recent trials of a nasal insulin vaccine in humans at risk of type 1 diabetes provide evidence of tolerance induction as a basis for clinical efficacy.Immunology and Cell Biology (2008) 86, 139–145; doi:10.1038/sj.icb.7100151; published online 8 January 2008 [ABSTRACT FROM AUTHOR]

Cells with the phenotype of intraepithelial lymphocytes (IEL) are present systemically and have been implicated in immune regulation. To determine whether IEL undergo homeostatic proliferation and migrate from the small intestine, we analysed the fate of congenic IEL transferred into lymphopenic mice. Donor IEL homed to the small intestinal epithelium, where they expanded in an IL-15-dependent manner and expressed CD69, CD44 and CD103; proliferation did not occur in the spleen, the main other site of IEL detection early after transfer. By 12 days after transfer, a small proportion of intestinal IEL had up-regulated the trafficking molecule CD62L. Four weeks after transfer, donor IEL with a CD69CD44CD103 phenotype similar to memory T cells were present in spleen and other extra-intestinal sites. Treatment of mice with blocking antibody to CD62L reduced appearance of cells in mesenteric lymph nodes; treatment with FTY720, a sphingosine 1-phosphate receptor agonist that blocks egress of T cells from lymph nodes, reduced appearance of cells in spleen. The distribution of TCR αβ and γδ IEL varied between organs, αβ IEL being predominant. IEL proliferation and emigration under lymphopenic conditions suggests similar IEL turnover, albeit at a lower level, under physiological conditions. [ABSTRACT FROM AUTHOR]

The ability to measure proliferation of autoantigen-specific T cells is critical for the evaluation of cellular immune function. Using a novel, sensitive, CFSE-based assay, we were able to directly quantitate autoantigenspecific CD4+ T cell proliferation. However, peripheral blood cells from healthy, pre-diabetic and diabetic donors exhibited overlap in responses to glutamic acid decarboxylase (GAD65) and proinsulin (PI). This indicates that autoantigen-induced CD4+ T cell proliferation in a functionally complex cell population may not discriminate disease in the general population. Clear discrimination was found between diabetic and healthy sibs, suggesting the need to standardize the genetic and environmental background. In addition, the ability of the CFSE assay to allow analysis of the phenotype and function of autoantigen-responsive T cells may improve discrimination. [ABSTRACT FROM AUTHOR]

Mutations in the triple PDZ domain-containing protein harmonin have been identified as the cause of Usher deafness syndrome type 1C. Independently, we identified harmonin in a screen for genes expressed in pancreaticβ cells. Using a yeast two-hybrid assay, we show that the first PDZ domain of harmonin interacts with a novel protein, designated harp forharmonin-interacting,ankyrinrepeat-containingprotein. This interaction was confirmed in an over-expression system and in mammalian cells, and shown to be mediated by the three C-terminal amino acids of harp. Harp is expressed in many of the same epithelia as harmonin and co-localization of native harp and harmonin was demonstrated by confocal microscopy in pancreatic duct epithelium and in a pancreaticβ-cell line. Harp, predicted molecular mass 48 kDa, has a domain structure which includes three ankyrin repeats and a sterile alpha motif. Humanharpmaps to chromosome 16, and its mouse homologue to chromosome 7. Sequences with similarity to harp include thesansgene, mutations of which are responsible for deafness in the Jackson shaker 2 (js) mutant mouse and in human Usher syndrome type 1G. The functional domain structures of harp and harmonin, their interaction under native conditions and their co-localization suggest they constitute a scaffolding complex to facilitate signal transduction in epithelia. [ABSTRACT FROM AUTHOR]

Fox A, Mountford J, Braakhuis A, Harrison LC. High avidity antibodies to fetal pig pancreas endocrine cells transfer rejection but are not normally generated to fetal pig pancreas xenografts. Xenotransplantation 2002; 9: 382–392. © Blackwell Munksgaard, 2002 Previous studies on the contribution of T cell-dependent antibody (Ab) to non-vascular xenograft rejection have yielded conflicting results, being confounded by the presence of recipient T cells and the use of different tissues and immunizing regimens to generate Ab. In the present study, the effect of adoptive transfer of Ab on fetal pig pancreas (FPP) and pig PK15 cell xenografts was examined in T cell-deficient severe combined immune deficiency (SCID) mice. T cell-dependent Abs raised by hyperimmunization with different cell types and by FPP transplantation were compared. Ab raised by hyperimmunization with pig thymocytes exhibited strong binding to pig thymocytes and PK15 cells but did not transfer FPP rejection. IgG1 and IgM, but not IgG3, Abs bound strongly to FPP exocrine and connective tissue, whereas binding to endocrine cells in vitro and in vivo was weak or absent. This pattern of Ab binding was similar to that observed after transplanting FPP into BALB/c mice. Furthermore, serum recovered from BALB/c mice 20 days after FPP transplantation bound strongly to non-endocrine but not endocrine cells and did not transfer FPP rejection. In contrast, serum from mice hyperimmunized with PK15 cells bound strongly to PK15 cells and transferred rejection of intraperitoneal PK15 cells. Furthermore, this serum contained IgG1 and IgM Abs that bound strongly, and IgG3 Abs that bound weakly, to endocrine cells in FPP, and also transferred rejection of FPP in SCID mice. These results indicate that endocrine cells express low concentrations of xenoreactive Ab epitopes and that high Ab concentrations and/or high avidity Abs are required for sufficient endocrine cell binding to cause damage and rejection... [ABSTRACT FROM AUTHOR]

Objective: Serum islet antibodies signify increased risk for type 1 diabetes (TID). Knowledge of the relationship between age and seroconversion would guide screening for at-risk individuals. We aimed to determine the effectiveness of islet antibody screening in early childhood, in particular the proportion of negative children who subsequently seroconverted. Methods: We identified 554 children with a first-degree relative with T1D who had tested negative for islet cell antibodies (ICA) and insulin autoantibodies (IAA) when first screened at a mean age of 7.2yr. Of 423 who were eligible, 350 consented to re-testing for ICA and IAA and antibodies to glutamic acid decarboxylase (GADAb) and tyrosine phosphatase-like insulinoma antigen IA-2 (IA2Ab) at a mean age of 11.1 yr. GADAb and IA2Ab were measured in 239 of the initial stored samples. Results: Of the 350 children who tested negative at first screening, 12 (3.4%) subsequently seroconverted, becoming positive for ICA (n 4), IAA (n = 7), GADAb (n = 6) or IA2Ab (n = 2). Of 239 initially negative for ICA and IAA, 8/239 (3.3%) now tested positive for GADAb (n = 7) or IA2Ab (n = 1). Four of these children were positive for GADAb in both tests; the one child initially positive for IA2Ab only was positive for all four antibodies 4.6yr later and developed diabetes. Conclusion: Screening for ICA and IAA failed to identify 2-3% of genetically at-risk children who subsequently developed islet antibodies. Testing for GADAb and IA2Ab would not have avoided this. Maximizing the sensitivity of detecting risk for T1D requires repeat screening for islet antibodies throughout childhood. [ABSTRACT FROM AUTHOR]

Summary Type 1 diabetes has been associated with an increased frequency of activated T cells and T-cell hyperactivity to non-specific and disease-specific stimuli including the islet autoantigen glutamic acid decarboxylase 65 (GAD). To address whether T-cell hyperactivity is genetic or acquired we measured whole blood cytokines in vitro in response to GAD or tetanus in 18 identical twin pairs, nine discordant for type 1 diabetes. In addition, the activity of 2′, 5′ oligoadenylate synthetase (OAS) in blood mononuclear cells was measured as a marker of viral infection. Interleukin-2 (IL-2) basally and IL-2 and interferon-γ (IFN-γ) in response to GAD, were detected more frequently and at higher levels in diabetic compared to non-diabetic twins. IL-10 was not different between groups. OAS activity was increased in diabetic compared to non-diabetic twins and showed a correlation with basal IL-2 and GAD-stimulated IFN-γ and IL-10. These findings suggest that T-cell hyperactivity in type 1 diabetes is an acquired trait and could reflect persisting virus expression. [ABSTRACT FROM AUTHOR]

Describes immune and other markers used for risk assessment and prediction, and prevention strategies in type I diabetes. Assay of Islet antibodies; Measurement of &β;-cell function; Discussion on Islet antibodies as markers of risk; Prospects for prevention; Costs of risk assessment.

Abstract: Environmental agents are proposed to play a role in triggering or exacerbating pancreatic islet autoimmunity in people genetically predisposed to type 1 diabetes. However, with few exceptions, these agents remain enigmatic. Clues to environmental agents may be found by investigating population/geographic clusters or ‘hotspots’ of high disease incidence. We were alerted to a small community where the incidence of type 1 diabetes appeared to be five-fold higher than expected. Because type 1 diabetes is now recognized to have a subclinical phase during which anti-islet antibodies can be detected, we aimed to identify and characterize a reservoir of children with subclinical disease in this community. Venous blood samples were collected from 1906/2347 (81%) local school children during one week. Islet cell antibodies (ICAs) were detected in 122 (6.4%) children, 18 (0.9%) being high titer (≥ 20 Juvenile Diabetes Foundation units (JDFu)). On retest, 15 months later, the majority of low titer ICAs were undetectable, whereas high-titer ICAs persisted. The latter were found in two distinct age-related, ethnically similar groups. The younger group, aged 6–9 yr, had antibodies to insulin (IAAs), glutamic acid decarboxylase (GAD) and tyrosine phosphatase IA2 in addition to ICA, human leukocyte antigen (HLA) genes associated with susceptibility to type 1 diabetes, and lower first-phase insulin responses (FPIRs) to intravenous glucose. The older group, aged 13–16 yr, the age cohort of the index clinical cases, had few antibodies other than ICA, non-susceptibility HLA genes and normal FPIRs. During follow-up, three children, all from the younger group with multiple antibodies and FPIRs less than the first percentile, developed diabetes 4, 6 and 7 yr after screening. The finding of two age groups of subclinical disease suggests that if environmental agents triggered islet autoimmunity they did not act constantly on the community.... [ABSTRACT FROM AUTHOR]

Summary: Although innate immunity evolved to combat pathogens, increasing awareness of a pivotal role in driving and shaping adaptive immunity has prompted this review on the role of innate immunity in graft rejection. We present evidence that grafts, especially xenografts, elicit innate responses, required for adaptive immunity. Particular attention is paid to studies by ourselves and others demonstrating the important role of innate immunity in T-cell trafficking. The mechanisms by which grafts elicit immunity are a fertile subject for further investigation and an important target for therapeutic intervention. [ABSTRACT FROM AUTHOR]

Summary: Mucosal delivery of soluble antigen induces systemic tolerance and has been applied to the prevention of autoimmune diseases. We have studied mucosal tolerance in autoimmune diabetes using the non-obese diabetic mouse model. Treatment of prediabetic mice with the pancreatic islet autoantigen insulin, by aerosol or intranasal delivery, reduces the incidence of diabetes and is associated with induction of CD8 (αα) γδ T cells, small numbers of which prevent adoptive transfer of diabetes. We examine the evidence for γδ T cells in mucosal tolerance and discuss possible mechanisms underlying the induction and action of insulin-induced CD8 γδ regulatory T cells. CD8 γδ cells constitute the most abundant subpopulation of intraepithelial lymphocytes (IELs), the major lymphoid cell compartment and first line of cellular immune defence in the mucosa. Induction of regulatory CD8 γδ T cells requires conformationally intact but not biologically active insulin. In contrast, intranasal (pro)insulin peptide, or oral insulin which is degraded in the gut, induces CD4 regulatory cells. Regulatory γδ T cells secrete interleukin-10 in pancreatic lymph nodes, which could account for the antidiabetic and bystander suppressor effect of naso-respiratory insulin. The physiological role of γδ IELs in maintaining peripheral self-tolerance deserves further study. [ABSTRACT FROM AUTHOR]

To obtain a better understanding of the immune response to Epstein-Barr virus (EBV), we measured the cytokines tumour necrosis factor (TNF)-ɑ/β, interleukin-2 (IL-2), interferongamma (IFN-γ), IL-6 and granulocyte-macrophage colony-stimulating factor (GM-CSF) in the conditioned medium of peripheral blood mononuclear cells from 10 healthy adults before and at 48 h and at 1, 2, 3 and 4 weeks following infection in vitro with EBV. Cultures were examined for regression of outgrowths of nascent virus-transformed B cells, and populations of cells in the cultures were analysed by flow cytometry. TNF-ɑ/β was not detected in infected or non-infected cultures. In infected cultures assayed at the nominated times, the highest levels of IL-2 were detected at 48 hours, IFN-γ at 1 week, IL-6 at 2 weeks and GM-CSF between 2 and 4 weeks. IL-6 and GM-CSF, but not IL-2 or IFN-γ, were detected in non-infected cultures but at lower levels than in infected cultures. Nine of the 10 healthy adults showed regression of outgrowths of virus-transformed B cells and, of these, seven had antibodies to the EBV capsid antigen (VCA). Strong regression was associated with sequential increases in IL-2, IFN-γ, and low levels of IL-6 and GM-CSF. Absent or weak regression was associated with an undetectable level of IL-2, a low level of IFN-γ, high levels of IL-6 and GM-CSF and an increased frequency of cells bearing the phenotype CD20 and HLA-DR in the final weeks of culture. The percentage of cells with a phenotypic marker for natural killer cells remained constant in all cultures over the 4 week period, and there was a modest decrease in the percentage of T cells in both infected and non-infected cultures. The demonstration of different temporal profiles of cytokines is in accord with a programmed cellular immune response to EBV infection which could serve as a model to study the events that modulate the inflammatory response to EBV. [ABSTRACT FROM AUTHOR]

The author reflects on the definition of the two sub-types of type 1 diabetes. The author says that the first sub-type is type 1A, which account for approximately 90% of cases of type 1 diabetes in Caucasians. The author also notes that the diabetes type 1B or idiophatic has clinical features of type 1A, however has no evidence of islet autoimmunity. The author cites that type 1B includes fulminant diabetes described in Japan that account for 15-20% of new-onset type 1 diabetes.

Type 1 diabetes is clinically heterogeneous but most children who develop type 1 diabetes have detectable autoantibodies before the age of 5 years to at least two islet antigens: insulin, glutamic acid decarboxylase 65 (GAD65), insulinoma antigen 2 (IA2) and/or zinc transporter 8 (ZnT8).[3] Diagnosis of ABCD before end-stage clinical type 1 diabetes and hyperglycaemia is a key step towards the prevention of type 1 diabetes. Australia is fortunate in having robust research networks of type 1 diabetes clinicians and researchers that monitor the natural history of type 1 diabetes in genetically at-risk families, screen for ABCD, and conduct intervention trials aiming to improve clinical outcomes. [Extracted from the article]

This article focuses on insulin resistance in children and adolescents with type 1 diabetes mellitus. This is the first large-scale study attempting to address the relationship between insulin resistance and adiposity in established T1D. Its strengths include the large number of subjects and clearly outlined analyses of the different subgroups. The use of insulin dose as an estimate of insulin resistance is understandable because other simple indices such as fasting insulin or the homeostasis model assessment of insulin resistance (HOMA-R) are not applicable in people with endogenous insulin deficiency, and the gold-standard but, invasive, eugylcemic hyperinsulinemic clamp methodology is not feasible in a large study of children.

The beta-cell mass in the adult pancreas possesses the ability to undergo limited regeneration following injury. Identifying the progenitor cells involved in this process and understanding the mechanisms leading to their maturation will open new avenues for the treatment of type 1 diabetes. However, despite steady advances in determining the molecular basis of early pancreatic development, the identification of pancreatic stem cells or beta-cell progenitors and the molecular mechanisms underlying beta-cell regeneration remain unclear. Recent advances in the directed differentiation of embryonic and adult stem cells has heightened interest in the possible application of stem cell therapy in the treatment of type 1 diabetes. Drawing on the expanding knowledge of pancreas development, beta-cell regeneration and stem cell research, this review focuses on progenitor cells in the adult pancreas as a potential source of beta-cells., (Copyright 2004 John Wiley & Sons, Ltd.)