Т- lymphocytes - «censorial» cells of immune system

Abstract

The characteristic of population Т-lymphocytes is presented. The variety of effects of these cells is connected with presence of many subpopulations which name small subpopulations helper T-lymphocytes: Тh1, Тh2, Тh3, Тh9, Тh17, Тh22. Mechanisms of activation of these cells and their role in development of mechanisms of the adaptive immune answer, and also possible variants of development of immune dysfunctions and an immune pathology are described. However, the leading part is allocated to the characteristic regulatory T-lymphocytes. From all subpopulations regulatory lymphocytes subpopulation CD4+CD25+high-Т-lymphocytes. Regulatory function autoimmunity а from these cells is most well investigated is shown already at early age. Given subpopulЫation Т-lymphocytes is capable to render suppressor influence on various types immunocompetent the cells providing functioning both congenital, and got immunity. Very important role in functioning CD4+CD25+high-Т-lymphocytes belongs transcriptional to factor FoxP3. It is established, that FoxP3 renders negative effect on activation of T-cells, possibly, owing to oppression efferent functions interleukin 2. Suppressor the effect of these cells is not limited to the T-cells specific to self-antigens. Their influence extends on all microenvironment lymphocytes. Regulatory function CD4+CD25+high-Т-lymphocytes is carried out by means of rendering cytotoxic effect on a cell-target by means of perforins, granzyme A and CD18 without participation of a Fas-receptor. CD4+CD25+high-Т-lymphocytes can render suppressor effect through production transforming growth the factor and expression him on a membrane of a cell. Except for these cells are described Тh3-lymphocytes and inducible regulatory cells. Effects which they cause, are connected with production transforming growth the factor, interleukins 4 and 10. The given biological functions lead to oppression of production of antibodies plasmacytes and modulate presenter activity of macrophages and dendritic cells.