Immunological profile of multiple sclerosis patients Abstrakt Multiple sclerosis is an autoimmune neurodegenerative disease affecting predominantly the white matter of the CNS and the spinal cord. The mechanism of disease progression is not yet fully understood. In this study we focused on a comparison of selected immunological markers between patients with multiple sclerosis who were naïve newly diagnosed, subsequently treated with Avonex (IFNβ1a) and healthy donors. The T cells (particulary cytotoxic CD8+ T cells) are the major population involved in pathogenesis of MS causing the demyelization of axons. Subpopulation of CD161+ Th cells has a potential to be very important in this process. We focused on the role of NK cells phenotype and function in autoimmune response of patients and their changes during the therapeutic intervention. Using flow cytometry we analyzed the distribution of NK, NKT, T cells and monocytes with special regard to the expression of CD161 and NKG2D molecules on their surface. We observed increase counts of CD161+ cells in subpopulations NK CD56bright , NK CD56dim , Th, Tc CD8bright , Tc CD8dim and decrease counts of NKG2D+ cells in subpopulations NK CD56bright , NK CD56dim , NKT, Th, Tc CD8bright , Tc CD8dim and monocytes. The decreased cytotoxic activity of NK cells in naïve MS...

Rheumatoid arthritis (RA) is a worldwide problem representing one of the most prevalent autoimmune diseases in the world. Despite the commonness of the disea- se, its pathogenesis has not been fully described. Immune cells ranging from antigen- presenting cells to T, B and NK cells playing various roles participate in the rheumatic process. In this work we concentrated on NK cells expressing a repertoire of activating and inhibitory receptors which influence their function in health and disease. We focused on the analysis of NK cell function and described its possible modulation by rheumatic autoantigens and multivalent glycodendrimers bearing 4 (GN4C) or 8 (GN8P) N-acetyl glucosamine moieties. The effect on NK cells and the glycosylation pathways was further studied in vitro. Finally, an in vivo study was performed on an animal model of RA - col- lagen-induced arthritis (CIA) to assess the effect of the compounds on clinical develop- ment of the disease and selected immune parameters. Comparison of NK cell cytotoxicity in patients suffering from RA, other inflam- matory diseases and healthy donors showed its impairment particularly in RA patients. Peripheral blood NK cells reacted to GN8P glycoconjugate by inhibition of their effector function in CD161 high-expressing samples. The MGAT5...

京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第20084号 / 医博第4177号 / 新制||医||1018(附属図書館) / 33200 / 京都大学大学院医学研究科医学専攻 / (主査)教授 生田 宏一, 教授 山田 亮, 教授 椛島 健治 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

Mucosal associated invariant T (MAIT) cells are a population of innate-like lymphocytes, with an emerging role in tuberculosis (TB). They are characterised by the expression of high levels of CD161 and IL-18Rα, possession of a Vα7.2⁺ T cell receptor (TCR), and restriction by the MHC class I-related protein (MR1). MAIT cells can be activated by MR1 presenting microbe-derived riboflavin metabolites; or, by the cytokines IL-12 and IL-18 in a TCR-independent fashion. How human MAIT cells integrate these signals for their activation in response to Mtb is unclear. Lymphatic TB (LNTB) is a common extra-pulmonary manifestation of TB; however, little is known about the status of MAIT cells in LNTB - or in other granulomatous diseases, such as sarcoidosis. In this study, an in vitro approach was used to probe MAIT cell activation by Mtb, and the roles of IL-12/-18, the TCR, cell-cell contact and the immunological synapse (IS). Following TCR ligation, TNFα expression was rapid and transient, and was enhanced following sustained IL-12/-18 exposure. IFNγ expression occurred following sustained exposure to ng/ml concentrations of IL-12/-18; however, alongside TCR stimulation, pg/ml concentrations were sufficient. Using an artificial bilayer system, CD161 was excluded from the central regions of the MAIT cell IS, whilst the distribution of IL-18Rα remained unaffected. In response to Mtb and BCG, MR1 was necessary for rapid activation and TNFα expression, IL-12/-18 were necessary for robust and sustained IFNy expression, whilst an anti-Mtb effect was indicated in an intracellular infection model. Assessment of patients with TB or sarcoid lymphadenopathy revealed a depletion of MAIT cells in the blood in sarcoidosis, but not LNTB. In both groups, MAIT cells could be detected within a proportion of sampled lymph nodes. Overall, these findings indicate the importance of inflammatory cytokine signals in the induction of high-intensity and sustained MAIT cell effector function, including in response to Mtb. The observation of a numerical deficiency of MAIT cells in sarcoidosis requires further investigation.