Detection of different cytokines of the CD4~+ CD25~+ regnlatory T cells in peripheral blood of gastric cancer patients and implication0

Objective To explore the role of cytokines in immune suppression mechanism of CD4~+ CD25~+ regulatory T cells and detect the level of cytokines secreted by the CD4~+ CD25~+ regulatory T cells and CD4~+ CD25~- T cells in peripheral blood of gastric cancer patients.Methods After CD4~+ CD25~+ T cells and CD4~+ CD25~- T cells were isolated by magnetic activated cell sorting (MACS),CD4~+ CD25~+ T cells and CD4~+ CD25~- T cells were cultured separately or co-cultured in different ratios.The IFN-γ,IL-10 and TGF-βlevels of CD~+ CD25~+ T and CD4~+ CD25~- T cells in vitro were determined by ELISA.Results The levels of suppressive cytokines (IL-10 and TGF-β) secreted by the CD4~+ CD25~+ T cells in the gastric cancer patients and healthy controls were significantly higher than CD4~+ CD25~- T cells,but the level of proliferative eytokine IFN-γwas much lower than CD4~+ CD25~- T cells (P＜0.01).CD4~+ CD25~+ T cells could obviously inhibit the IFN-γproduction by CD4~+ CD25~- T cells in vit- ro (P＜0.01) in an effect-ratio relationship.However,co-culture of CD4~+ CD25~+ T cells and CD4~+ CD25~- T cells had no effect on IL-10 and TGF-βproduction (P＞0.01 ).Conclusion The cytokines may have some effects in the immune suppression mechanism of CD4~+ CD25~+ regulatory T cells in vitro.