MINOR SUBSETS OF T-HELPER CELLS (Th THYMIC NAIVE, Th CENTRAL NAIVE, Th9, Th22 AND CD4+CD8+ DOUBLE POSITIVE T-CELLS)

Abstract. T cell populations, specifically, T helper (Th) cells, are among key players in the processes occurring in the body following exposure to a foreign antigen. Usage of new, highly sensitive instruments allowed of more detailed studies of their structural arrangement, as well as to detect a number of functionally significant minor subsets. These T cell subtypes were characterized both phenotypically and functionally. Present review article concerns Th thymic naїve subsets, Th central naїve subpoppulations, Th9, Th22, and CD4+CD8+ doublepositive T cells. Their role and functional significance is discussed in various pathological conditions. At present time, there are convincing data about specific arrays of membrane molecules, transcription factors, production of specific mediators typical to either of these subsets. Application of these markers in laboratory studies, will certainly improve diagnostic quality when evaluating functional alterations of immune system and adequacy of prescribed immunotherapy.