Expression of the enteroviral capsid protein VP1 in the islet cells of patients with type 1 diabetes is associated with induction of protein kinase R and downregulation of Mcl-1

The final publication is available at link.springer.com/article/10.1007%2Fs00125-012-2745-4Immunohistochemical staining reveals that the enteroviral capsid protein VP1 is present at higher frequency in the insulin-containing islets of patients with recent-onset type 1 diabetes than in controls. This is consistent with epidemiological evidence suggesting that enteroviral infection may contribute to the autoimmune response in type 1 diabetes. However, immunostaining of VP1 is not definitive since the antibody widely used to detect the protein (Clone 5D8/1) might also cross-react with additional proteins under some conditions. Therefore, we sought to verify that VP1 immunopositivity correlates with additional markers of viral infection

Differential insulitic profiles determine the extent of beta cell destruction and the age at onset of type 1 diabetes

Published onlineJOURNAL ARTICLEType 1 diabetes (T1D) results from a T-cell mediated destruction of pancreatic beta cells following the infiltration of leukocytes (including CD8+, CD4+ and CD20+ cells) into and around pancreatic islets ("insulitis"). Recently, we reported that two distinct patterns of insulitis occur in patients with recent-onset T1D from the UK and that these differ principally in the proportion of infiltrating CD20+ B-cells (designated "CD20Hi" and "CD20Lo" respectively). We have now extended this analysis to include patients from the nPOD (USA) and DiViD (Norway) cohorts and confirm that the two profiles of insulitis occur more widely. Moreover, we show that patients can be directly stratified according to their insulitic profile and that those receiving a diagnosis before the age of 7 years always display the CD20Hi profile. By contrast, individuals diagnosed beyond the age of 13 years are uniformly defined as CD20Lo. This implies that the two forms of insulitis are differentially aggressive and that patients with a CD20Hi profile lose their beta cells at a more rapid rate. In support of this, we also find that the proportion of residual insulin-containing islets (ICIs) increases in parallel with age at onset of T1D. Importantly, those diagnosed in, or beyond, their teenage years retain ∼40% ICIs at diagnosis, implying that a functional deficit rather than absolute beta cell loss may be causal for disease onset in these patients. We conclude that appropriate patient stratification will be critical for correct interpretation of the outcomes of intervention therapies targeted to islet-infiltrating immune cells in T1D

Gene expression profiling in NOD mice reveals that B cells are highly educated by the pancreatic environment during autoimmune diabetes

Aims/hypothesis: B cells play an important role in driving the development of type 1 diabetes; however, it remains unclear how they contribute to local beta cell destruction during disease progression. Here, we use gene expression profiling of B cell subsets identified in inflamed pancreatic tissue to explore their primary functional role during the progression of autoimmune diabetes. Methods: Transcriptional profiling was performed on FACS-sorted B cell subsets isolated from pancreatic islets and the pancreatic lymph nodes of NOD mice. Results: B cells are highly modified by the inflamed pancreatic tissue and can be distinguished by their transcriptional profile from those in the lymph nodes. We identified both a discrete and a core shared gene expression profile in islet CD19+CD138– and CD19+CD138+ B cell subsets, the latter of which is known to have enriched autoreactivity during diabetes development. On localisation to pancreatic islets, compared with CD138– B cells, CD138+ B cells overexpress genes associated with adhesion molecules and growth factors. Their shared signature consists of gene expression changes related to the differentiation of antibody-secreting cells and gene regulatory networks associated with IFN signalling pathways, proinflammatory cytokines and Toll-like receptor (TLR) activation. Finally, abundant TLR7 expression was detected in islet B cells and was enhanced specifically in CD138+ B cells. Conclusions/interpretation: Our study provides a detailed transcriptional analysis of islet B cells. Specific gene signatures and interaction networks have been identified that point towards a functional role for B cells in driving autoimmune diabetes. Graphical abstract

Detection of a low-grade enteroviral infection in the islets of Langerhans of living patients newly diagnosed with type 1 diabetes

Journal ArticleThis is an author-created, uncopyedited electronic version of an article accepted for publication in Diabetes. The American Diabetes Association (ADA), publisher of Diabetes, is not responsible for any errors or omissions in this version of the manuscript or any version derived from it by third parties. The definitive publisher-authenticated version is available in Diabetes, May 2015, vol. 64, no. 5 pp. 1682-1687 in print and online at http://diabetes.diabetesjournals.org/content/64/5/1682.abstractThe Diabetes Virus Detection study (DiViD) is the first to examine fresh pancreatic tissue at the diagnosis of type 1 diabetes for the presence of viruses. Minimal pancreatic tail resection was performed 3-9 weeks after onset of type 1 diabetes in six adult patients (age 24-35 years). The presence of enteroviral capsid protein 1 (VP1) and the expression of class I HLA were investigated by immunohistochemistry. Enterovirus RNA was analyzed from isolated pancreatic islets and from fresh-frozen whole pancreatic tissue using PCR and sequencing. Nondiabetic organ donors served as controls. VP1 was detected in the islets of all type 1 diabetic patients (two of nine controls). Hyperexpression of class I HLA molecules was found in the islets of all patients (one of nine controls). Enterovirus-specific RNA sequences were detected in four of six patients (zero of six controls). The results were confirmed in various laboratories. Only 1.7% of the islets contained VP1(+) cells, and the amount of enterovirus RNA was low. The results provide evidence for the presence of enterovirus in pancreatic islets of type 1 diabetic patients, which is consistent with the possibility that a low-grade enteroviral infection in the pancreatic islets contributes to disease progression in humans.Academy of FinlandSouth-Eastern Norway Regional HealthAuthorityNovo Nordisk FoundationPEVNET (Persistent Virus Infection in Diabetes Network) Study GroupEuropean Union’s Seventh Framework ProgrammeSwedish Medical Research CouncilDiabetes Wellness FoundationJDR

Blood and islet phenotypes indicate immunological heterogeneity in type 1 diabetes

This is an author-created, uncopyedited electronic version of an article accepted for publication in Diabetes. The American Diabetes Association (ADA), publisher of Diabetes, is not responsible for any errors or omissions in this version of the manuscript or any version derived from it by third parties. The definitive publisher-authenticated version is available in Diabetes in print and online at http://diabetes.diabetesjournals.orgThe erratum to this article is available in ORE at http://hdl.handle.net/10871/40335Studies in type 1 diabetes indicate potential disease heterogeneity, notably in the rate of β-cell loss, responsiveness to immunotherapies, and, in limited studies, islet pathology. We sought evidence for different immunological phenotypes using two approaches. First, we defined blood autoimmune response phenotypes by combinatorial, multiparameter analysis of autoantibodies and autoreactive T-cell responses in 33 children/adolescents with newly diagnosed diabetes. Multidimensional cluster analysis showed two equal-sized patient agglomerations characterized by proinflammatory (interferon-γ-positive, multiautoantibody-positive) and partially regulated (interleukin-10-positive, pauci-autoantibody-positive) responses. Multiautoantibody-positive nondiabetic siblings at high risk of disease progression showed similar clustering. Additionally, pancreas samples obtained post mortem from a separate cohort of 21 children/adolescents with recently diagnosed type 1 diabetes were examined immunohistologically. This revealed two distinct types of insulitic lesions distinguishable by the degree of cellular infiltrate and presence of B cells that we termed "hyper-immune CD20Hi" and "pauci-immune CD20Lo." Of note, subjects had only one infiltration phenotype and were partitioned by this into two equal-sized groups that differed significantly by age at diagnosis, with hyper-immune CD20Hi subjects being 5 years younger. These data indicate potentially related islet and blood autoimmune response phenotypes that coincide with and precede disease. We conclude that different immunopathological processes (endotypes) may underlie type 1 diabetes, carrying important implications for treatment and prevention strategies.JDRFNational Institute for Health Research (NIHR) Biomedical Research Centre based at Guy’s and St Thomas’ NHS Foundation Trust and King’s College LondonEuropean Union (EU FP7) award - Persistent Virus Infection in Diabetes Network Study Group (PEVNET)EU FP7 Large-Scale Focused Collaborative Research Project on Natural Immunomodulators as Novel Immunotherapies for Type 1 Diabetes (NAIMIT)EU FP7 Large-Scale Focused Collaborative Research Project on β-cell preservation through antigen-specific immunotherapy in Type 1 Diabetes: Enhanced Epidermal Antigen Delivery Systems (EE-ASI)National Institutes of Health (NIH)National Institute of Diabetes and Digestive and Kidney DiseasesNational Institute of Allergy and Infectious DiseasesEunice Kennedy Shriver National Institute of Child Health and Human DevelopmentNational Center for Research ResourcesGeneral Clinical Research CenterAmerican Diabetes Association (ADA

Single-cell RNAseq identifies clonally expanded antigen-specific T-cells following intradermal injection of gold nanoparticles loaded with diabetes autoantigen in humans

Gold nanoparticles (GNPs) have been used in the development of novel therapies as a way of delivery of both stimulatory and tolerogenic peptide cargoes. Here we report that intradermal injection of GNPs loaded with the proinsulin peptide C19-A3, in patients with type 1 diabetes, results in recruitment and retention of immune cells in the skin. These include large numbers of clonally expanded T-cells sharing the same paired T-cell receptors (TCRs) with activated phenotypes, half of which, when the TCRs were re-expressed in a cell-based system, were confirmed to be specific for either GNP or proinsulin. All the identified gold-specific clones were CD8+, whilst proinsulin-specific clones were both CD8+ and CD4+. Proinsulin-specific CD8+ clones had a distinctive cytotoxic phenotype with overexpression of granulysin (GNLY) and KIR receptors. Clonally expanded antigen-specific T cells remained in situ for months to years, with a spectrum of tissue resident memory and effector memory phenotypes. As the T-cell response is divided between targeting the gold core and the antigenic cargo, this offers a route to improving resident memory T-cells formation in response to vaccines. In addition, our scRNAseq data indicate that focusing on clonally expanded skin infiltrating T-cells recruited to intradermally injected antigen is a highly efficient method to enrich and identify antigen-specific cells. This approach has the potential to be used to monitor the intradermal delivery of antigens and nanoparticles for immune modulation in humans

Abnormal neutrophil signature in the blood and pancreas of presymptomatic and symptomatic type 1 diabetes

BACKGROUND. Neutrophils and their inflammatory mediators are key pathogenic components in multiple autoimmune diseases, while their role in human type 1 diabetes (T1D), a disease that progresses sequentially through identifiable stages prior to the clinical onset, is not well understood. We previously reported that the number of circulating neutrophils is reduced in patients with T1D and in presymptomatic at-risk subjects. The aim of the present work was to identify possible changes in circulating and pancreas-residing neutrophils throughout the disease course to better elucidate neutrophil involvement in human T1D. METHODS. Data collected from 389 subjects at risk of developing T1D, and enrolled in 4 distinct studies performed by TrialNet, were analyzed with comprehensive statistical approaches to determine whether the number of circulating neutrophils correlates with pancreas function. To obtain a broad analysis of pancreas-infiltrating neutrophils throughout all disease stages, pancreas sections collected worldwide from 4 different cohorts (i.e., nPOD, DiViD, Siena, and Exeter) were analyzed by immunohistochemistry and immunofluorescence. Finally, circulating neutrophils were purified from unrelated nondiabetic subjects and donors at various T1D stages and their transcriptomic signature was determined by RNA sequencing. RESULTS. Here, we show that the decline in β cell function is greatest in individuals with the lowest peripheral neutrophil numbers. Neutrophils infiltrate the pancreas prior to the onset of symptoms and they continue to do so as the disease progresses. Of interest, a fraction of these pancreasinfiltrating neutrophils also extrudes neutrophil extracellular traps (NETs), suggesting a tissue-specific pathogenic role. Whole-transcriptome analysis of purified blood neutrophils revealed a unique molecular signature that is distinguished by an overabundance of IFN-associated genes; despite being healthy, said signature is already present in T1D-autoantibody-negative at-risk subjects. CONCLUSIONS. These results reveal an unexpected abnormality in neutrophil disposition both in the circulation and in the pancreas of presymptomatic and symptomatic T1D subjects, implying that targeting neutrophils might represent a previously unrecognized therapeutic modality

The Effect of Age on the Progression and Severity of Type 1 Diabetes: Potential Effects on Disease Mechanisms

International audiencePURPOSE OF REVIEW:To explore the impact of age on type 1 diabetes (T1D) pathogenesis.RECENT FINDINGS:Children progress more rapidly from autoantibody positivity to T1D and have lower C-peptide levels compared to adults. In histological analysis of post-mortem pancreata, younger age of diagnosis is associated with reduced numbers of insulin containing islets and a hyper-immune CD20hi infiltrate. Moreover compared to adults, children exhibit decreased immune regulatory function and increased engagement and trafficking of autoreactive CD8+ T cells, and age-related differences in β cell vulnerability may also contribute to the more aggressive immune phenotype observed in children. To account for some of these differences, HLA and non-HLA genetic loci that influence multiple disease characteristics, including age of onset, are being increasingly characterized. The exception of T1D as an autoimmune disease more prevalent in children than adults results from a combination of immune, metabolic, and genetic factors. Age-related differences in T1D pathology have important implications for better tailoring of immunotherapies

Detection of enterovirus in the islet cells of patients with type 1 diabetes: what do we learn from immunohistochemistry? Reply to Hansson SF, Korsgren S, Pontén F et al [letter].

CommentLetterAuthor version of comment article submitted to Diabetologia. The final publication is available at Springer via http://dx.doi.org/10.1007/s00125-014-3167-2Comment on Detection of enterovirus in the islet cells of patients with type 1 diabetes: what do we learn from immunohistochemistry? [Diabetologia. 2014] Evaluation of the fidelity of immunolabelling obtained with clone 5D8/1, a monoclonal antibody directed against the enteroviral capsid protein, VP1, in human pancreas. [Diabetologia. 2014