Regulative role of specific cytokine on expression of T-helper 17 cells and regulatory T cells

Abstract

Objective To investigate the roles of a variety of cytokines including transforming growth factor beta (TGF-β),interleukin-6 (IL-6) and interleukin-2 (IL-2) in the differentiation of CD+4 Tlymphocyte cells.Methods T lymphocyte cells either in human peripheral blood or routine spleen were cultured in vitro under different stimulation conditions.Flow cytometry was used to analyze the percentages of CD+4IL-17+ T-helper 17(Th17) cells,CD+8 IL-17+ T cells,CD+4 CD+25 FOXP+3 T regulatory (Treg) cells among activated T cells.Results Differentiation of Treg cells,Th17 cells and CD+8 IL-17+ T lymphocyte cells was enhanced when murine splenic T cells were cultured with TGF-β.The levels of expression were (7.8±2.2)%,(12.6±3.1)%,(10.1±2.6)% ,respectively.Experimental control group was severally same type of T cells without cytokine treatment.The levels of expression were (4.8±0.6) %,(1.7±0.5) %,(1.0±0.4) %,respectively.There were statistically significant differences among them (q=4.09,8.80,9.61.P<0.05 or P<0.01).Under combination treatment with IL-6 and TGF-β,(17.8±5.3) % Th17 cells and (15.0±4.2)% CDCD+8 IL-17CD+ T cells were induced,whereas the levels of Treg cells whose differentiation were restrained were (4.1±1.2) %.The differences were statistically significant compared with the level of same type of T cells in TGF-β group (q=5.03,5.17,5.04,P<0.01).Moreover,combination treatment with IL-2 and TGF-β decreased percentages of Th17 and CDCD+8 IL-17CD+ T cells and increased percentages of Treg cells in T cell population.There was an opposite effect when anti-IL-2 was apphed.The percentages of Th17 and CD+8 IL-17+ T cells were increased and the percentages of Treg cells were reduced The regulation trend of T lymphocyte cells in human peripheral blood was similar with those in routine spleen.Conclusion Various cytokines are of great importance in the regulation of the balance between Th17 and Treg cell. Key words: Cytokines; T-lymphocytes,helper-inducer; T-lymphocytes,regulatory