Expression features of genetic landscape which predispose an individual to the type 1 diabetes are poorly understood. We addressed this question by comparing gene expression profile of freshly isolated peripheral blood mononuclear cells isolated from either patients with type 1 diabetes (T1D), or their first‐degree relatives or healthy controls. Our aim was to establish whether a distinct type of ‘prodiabetogenic’ gene expression pattern in the group of relatives of patients with T1D could be identified. Whole‐genome expression profile of nine patients with T1D, their ten first‐degree relatives and ten healthy controls was analysed using the human high‐density expression microarray chip. Functional aspects of candidate genes were assessed using the MetaCore software. The highest number of differentially expressed genes (547) was found between the autoantibody‐negative healthy relatives and the healthy controls. Some of them represent genes critically involved in the regulation of innate immune responses such as TLR signalling and CCR3 signalling in eosinophiles, humoral immune reactions such as BCR pathway, costimulation and cytokine responses mediated by CD137, CD40 and CD28 signalling and IL‐1 proinflammatory pathway. Our data demonstrate that expression profile of healthy relatives of patients with T1D is clearly distinct from the pattern found in the healthy controls. That especially concerns differential activation status of genes and signalling pathways involved in proinflammatory processes and those of innate immunity and humoral reactivity. Thus, we posit that the study of the healthy relative’s gene expression pattern is instrumental for the identification of novel markers associated with the development of diabetes.

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Brooke-Spiegler syndrome (BSS) and its phenotypic variants, multiple familial trichoepithelioma (MFT) and familial cylindromatosis, are rare autosomal dominant hereditary diseases. They are characterized by the presence of multiple adnexal tumors, especially cylindromas, spiradenomas, spiradenocylindromas, and trichoepitheliomas. Implicated in the pathogenesis of the disease is the gene CYLD, which is localized on the long arm of chromosome 16. This gene encodes an evolutionarily conserved protein belonging to the deubiquitinating enzymes family, which plays a key role in many signaling pathways, especially in NF-κB, JNK, and Wnt. Less than 90 germline mutations of CYLD have been identified in patients with BSS/MFT. These mutations are mostly small alterations in the coding sequence and at exon-intron junction sites. One patient with an intronic mutation and another with a large CYLD deletion have also been recorded. In this study, the authors have analyzed a cohort of 14 patients with BSS/MFT from 13 families for large genome rearrangements by array comparative genome hybridization followed by confirmatory sequencing. We identified 2 large deletions, namely c.-34111_*297858del378779 and c.914-6398_1769del13642ins20 in patients with MFT and BSS, respectively. All other analyzable patients did not reveal any copy number alteration. It is concluded that the large rearrangements are relatively rare in patients without a germline CYLD mutation demonstrable by conventional sequencing. The pathogenetic mechanisms in patients with BSS/MFT lacking germline sequence alterations or large rearrangements in the CYLD gene remain to be clarified.

Type 1 diabetes (T1D) is an autoimmune disease characterized by the lack of insulin due to an autoimmune destruction of pancreatic beta cells. Here, we report a unique case of a family with naturally conceived quadruplets in which T1D was diagnosed in two quadruplets simultaneously. At the same time, the third quadruplet was diagnosed with the pre-diabetic stage. Remarkably, all four quadruplets were positive for anti-islet cell antibodies, GAD65 and IA-A2. Monozygotic status of the quadruplets was confirmed by testing 14 different short tandem repeat polymorphisms. Serological examination confirmed that all quadruplets and their father suffered from a recent enteroviral infection of EV68-71 serotype. To assess the nature of the molecular pathological processes contributing to the development of diabetes, immunocompetent cells isolated from all family members were characterized by gene expression arrays, immune-cell enumerations and cytokine-production assays. The microarray data provided evidence that viral infection, and IL-27 and IL-9 cytokine signalling contributed to the onset of T1D in two of the quadruplets. The propensity of stimulated immunocompetent cells from non-diabetic members of the family to secrete high level of IFN-a further corroborates this conclusion. The number of T regulatory cells as well as plasmacytoid and/or myeloid dendritic cells was found diminished in all family members. Thus, this unique family is a prime example for the support of the so-called 'fertile-field' hypothesis proposing that genetic predisposition to anti-islet autoimmunity is 'fertilized' and precipitated by a viral infection leading to a fully blown T1D.

Simultaneous detection of biological molecules by means of indirect immunolabeling provides valuable information about their localization in cellular compartments and their possible interactions in macromolecular complexes. While fluorescent microscopy allows for simultaneous detection of multiple antigens, the sensitive electron microscopy immunodetection is limited to only two antigens. In order to overcome this limitation, we prepared a set of novel, shape-coded metal nanoparticles readily discernible in transmission electron microscopy which can be conjugated to antibodies or other bioreactive molecules. With the use of novel nanoparticles, various combinations with commercial gold nanoparticles can be made to obtain a set for simultaneous labeling. For the first time in ultrastructural histochemistry, up to five molecular targets can be identified simultaneously. We demonstrate the usefulness of the method by mapping of the localization of nuclear lipid phosphatidylinositol-4,5-bisphosphate together with four other molecules crucial for genome function, which proves its suitability for a wide range of biomedical applications.

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Type 1 Diabetes (T1D) is considered to be a T-helper- (Th-) 1 autoimmune disease; however, T1D pathogenesis likely involves many factors, and sufficient tools for autoreactive T cell detection for the study of this disease are currently lacking. In this study, using gene expression microarrays, we analysed the effect of diabetes-associated autoantigens on peripheral blood mononuclear cells (PBMCs) with the purpose of identifying (pre)diabetes-associated cell processes. Twelve patients with recent onset T1D, 18 first-degree relatives of the TD1 patients (DRL; 9/18 autoantibody positive), and 13 healthy controls (DV) were tested. PBMCs from these individuals were stimulated with a cocktail of diabetes-associated autoantigens (proinsulin, IA-2, and GAD65-derived peptides). After 72 hours, gene expression was evaluated by high-density gene microarray. The greatest number of functional differences was observed between relatives and controls (69 pathways), from which 15% of the pathways belonged to “immune response-related” processes. In the T1D versus controls comparison, more pathways (24%) were classified as “immune response-related.” Important pathways that were identified using data from the T1D versus controls comparison were pathways involving antigen presentation by MHCII, the activation of Th17 and Th22 responses, and cytoskeleton rearrangement-related processes. Genes involved in Th17 and TGF-beta cascades may represent novel, promising (pre)diabetes biomarkers.

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