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Differentiation of adult stem cells into insulin-producing beta cells
Koblas, Tomáš ; Saudek, František (advisor) ; Grim, Miloš (referee) ; Štechová, Kateřina (referee)
Ph.D. Thesis abstract: Diabetes mellitus is a chronic disease characterized by a metabolic disorder in which there is a low level or complete lack of the insulin. Diabetes mellitus type 1 (DM1) is caused by an autoimmune reaction leading to the destruction of the insulin producing beta cells in the pancreas. In consequence, low or non-existent insulin production leads to a complete dependence on exogenous insulin supplementation. DM1 causes serious long-term complications. Although strict control of blood sugar could prevent the onset and development of diabetic complications only 5% of diabetic patients are able to achieve such control. Hence it is evident that the current methods of treatment are neither sufficient to treat this disease, nor prevent late complications in most patients. The most promising therapeutic approach in the treatment of diabetes is the restoring of insulin production. One such method is the transplantation of insulin-producing tissue. However, a lack of available insulin- producing tissue limits such therapeutic approach. Therefore an alternative source of insulin producing cells have to be found to obtain a sufficient amount of safe and efficient insulin producing tissue. Pancreatic stem/progenitor cells could represent such an available alternative source. Despite the evidence...
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Effect of diabetogenic autoantigens on the cytokine production of peripheral blood mononuclear cells from type 1 diabetic patients
Labiková, Jana ; Štechová, Kateřina (advisor) ; Holáň, Vladimír (referee)
5 Abstract Type 1 diabetes (T1D) is a serious organ-specific autoimmune disease characterised by irreversible destruction of pancreatic β-cells by immune system. This process results in an absolute insulin deficiency. Both genetical predisposition and environmental factors influence the development of the disease. β-cell destruction is mediated by cellular components of an immune system. Proinflammatory Th1 response is considered as most pathological. Autoimmune destruction of β-cells can be identified by the detection of specific serum autoantibodies a long time before the T1D clinical onset. Currently, there is no efficient cure available to prevent or at least to delay the destructive insulitis. This diploma thesis describes the influence of synthetic diabetogenic autoantigens GAD65 and IA2 on the cytokine response of peripheral blood mononuclear cells (PBMC) obtained from T1D patients with regards to their antibody profile. The study has been carried out on patients with confirmed T1D diagnosis who tested positive for anti-GAD65 and/or anti-IA2 autoantibodies. By using flow cytometry we measured the cell type ratio in PBMC samples. The cells have been stimulated by three different concentrations of antigens and their IFNγ and IL-17 production has been detected by ELISPOT assay. In the case of both...
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Dendritic cells and autoimmune diseases with a view to type 1 diabetes mellitus
Chrástová, Iveta ; Štechová, Kateřina (advisor) ; Krulová, Magdaléna (referee)
Dendritic cells (DC) are professional antigen-presenting cells (APC) that play an essential role in the induction of immune responses. DCs develop from CD34+ hematopoietic stem cells in bone marrow and their role is uptake, processing and presentation of antigens to T cells. DCs can be divided into two distinct subset of cells, myeloid a plasmacytoid DCs. Myeloid DCs (mDC) develop from hematopoietic cells in the presence of GM-CSF and TNF-α or from monocytes in the culture with GM-CSF and IL-4, then with CD40L they mature and produce a large number of IL-12, which is important in driving CD4+ T cell to type Th1. The development of pDC is CD40L and IL-3 dependent and Flt3-L supports this process as well. The essential role of pDC is that they secrete a large amounts of type I IFN in the responses to viruses and so they maintain the antiviral stage. To recognize the viruses pDC express Toll-like receptors 7/9. DCs have on the surface also other groups of receptors, e.g. C-type lectin-like receptors, RIG-I-like receptors and NOD-like receptors. They play the role in the various diseases, mostly autoimmune diseases, in which the immune system recognizes self tissues and activates against them the immune response. Dendritic cells function is that they are competent to activate T cells, in the most cases...
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Immunogenetic studies on autoimmune diabetes mellitus
Kološtová, Katarína ; Černá, Marie (advisor) ; Mateička, František (referee) ; Štechová, Kateřina (referee)
Immunogenetic studies on autoimmune diabetes. Aims of the study: The study has to characterize the genetic background of patients with different types of diabetes mellitus (T1D in children, T1D in adults, LADA, T2D, MODY). The relationship of the diabetes associated HLA-DRB1*04 and NFKB1 genes to the disease course was proved further in the functional studies of the mRNA gene expression. Patients were divided into the tested subgroups in relation to the HLA class II, NFKB1, and NFKBIA genotypes and disease type (T1DM in children, T1DM in adults, and LADA). Results and Conclusion: According to our findings we can conclude that the progression of the diabetes in T1D adults, T1D children and LADA is strongly influenced by different immunogenetic background modifying the ethiopathogenesis of diabetes in the above described groups. Our results offer new possibilities for the population risk testing and may be that far used in the future for better diagnostics of the diabetic's adults.
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Th17 lymphocytes and autoimmunity diseases with the intention of diabetes 1. type
Labiková, Jana ; Procházková, Jana (referee) ; Štechová, Kateřina (advisor)
Th17 cells were recently identified as a cell source of IL-17. They turned up to be a T cell lineage independent of previously described Th1 and Th2. The differentiation of naive CD4+ T cells towards Th17 requires the combination of TGFβ (a cytokine essential for the development of anti-inflammatory regulatory T cells) plus IL-6 or IL-21. IL-23 is required for in vivo function and phenotype maintenance of Th17. STAT3 and RORγt were identified as pivotal transcription factors in Th17 differentiation program. Th17 proved to have pro- inflammatory effects and are characterized by the production of IL-17A, IL-17F and IL-22 - cytokines implicated in host defense against certain extracellular pathogens. The cytokine products of Th17 cells act on wide range of cell types. They induce cytokines, chemokines and metalloproteinases and they also mediate neutrophil recruitment and production of antimicrobial peptides. Autoreactive Th17 are highly pathogenic and the production of IL-17 has been detected in several autoimmune diseases such as rheumatoid arthritis, multiple sclerosis, psoriasis, Crohn's disease and type 1 diabetes. These diseases were thought to be mediated by Th1 cells, but it is becoming increasingly clear that the regulation of autoimmunity is influenced at least in some diseases by Th17 cells as well.
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