Healthy first-degree relatives of patients with type 1 diabetes exhibit significant differences in basal gene expression pattern of immunocompetent cells compared to controls: expression pattern as predeterminant of autoimmune diabetes.

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.

Influence of maternal hyperglycaemia on cord blood mononuclear cells in response to diabetes-associated autoantigens.

UNLABELLED: Perfect maternal diabetes compensation is crucial for the outcome of the baby. However, little is known how hyperglycaemia influences the specific immune response. Furthermore, babies of type 1 diabetes (T1D) mothers have less risk of development T1D than babies with a T1D father. This study aimed to analyze the effect of maternal hyperglycaemia on newborns with focus on the response to diabetes-associated autoantigens. POPULATIONS: (1) Newborns of T1D mothers split into groups according to maternal diabetes compensation during the 3rd trimester: perfect (n = 15) or acceptable (n = 25) compensation. (2) newborns with T1D father (n = 12) (3) newborns with a mother treated for either gestational or type 2 diabetes (n = 10) (4) control newborns (n = 25). Spontaneous as well as diabetes-associated autoantigen-stimulated production of 23 cytokines and chemokines were tested using protein microarray. In addition, the influence of glucose on cytokine and chemokine responsiveness was analyzed in vitro. The study groups differed in their spontaneous as well as stimulated cytokine and chemokine spectra. A prominent Th1 response (high IFN-gamma) from autoantigen stimulation was observed especially in babies of T1D fathers (P = 0.001) and also in mothers with perfect diabetes compensation during the 3rd trimester (P = 0.016) in comparison with control newborns. By contrast, cord blood mononuclear cells cultivated in vitro in high glucose concentration decreased the diabetogenic stimulated Th1 cytokine response. Maternal 'sweet' as well as 'autoimmune environment' may both lead to lower occurrence of T1D within their offspring. Further studies will reveal the exact immunological mechanism of this observation.

Reactivity to Helicobacter pylori antigens in patients suffering from thyroid gland autoimmunity.

The role of infection in autoimmunity is widely discussed. In this study we concentrated on relationship between HELICOBACTER PYLORI as a very important gastroduodenal pathogen and autoimmune thyroiditis (AT). Forty seven AT patients and 34 healthy controls were enrolled. They were split into: THP ( H.PYLORI positive patients, n=17), THN ( H.PYLORI negative patients, n=30), CP ( H.PYLORI positive controls, n=17) and CN groups ( H.PYLORI negative controls, n=17). By protein microarray we analysed production of 23 cytokines and chemokines prior and post stimulation with H.PYLORI lysate and its lipopolysaccharide (LPS). Reactivity to lysate as well as to bacterial LPS differed within groups. The lowest basal cytokine and chemokine production was observed in CN group but these subjects reacted significantly to specific stimulation by increasing IFN-gamma (in comparison with THP p=0.01 for LPS and p=0.004 for H.PYLORI lysate) and TGF-beta production (p=0.015 for LPS). In contrast, IL-10 and IL-5 were decreased in this group. In CP, THN and THP groups, we observed in general higher chemokine response. THP group increased proinflammatory IL-6 after specific stimulation as well (in comparison with CP p<0.0001 for LPS stimulation). We observed different "reactivity pattern" to H.PYLORI within groups with low basal cytokine and chemokine production in healthy H.PYLORI negative controls but with clear specific response in IFN-gamma and TGF-beta production in this group. Adequate immune reaction which is joined to appropriate immunoregulation leads to prevention of the chronic infection and on the other hand may prevent the development of "connected" diseases such as autoimmune.