RESUMEN
Objective To established the method of increasihg the proportion of T regulatory cells(Tr) to T effector cells(Te), which could suppresses allogeneic ahtigen reaction, by in vivo of glucocorti-coid (dexamethasone, DXM) combined with IL-2. Methods After combined treatment to male C57BL/6N mice (donor) with DXM(5 mg. kg-1· d-1 ) and IL-2 (300 000 IU · mouse-1·d-1) for 3 d, spleen mono-nuclear cells were made and were carried out by flow cytometry analysis. Using the spleen cells of BALB/c mice as aliogeneic antigen to stimulate the spleen cells of male C57BL/6N mice for 7 d after combined treat-ment of glucoeorticoid and IL-2, the reaction of cell proliferation was detected. Results After the treatrment of DXM and IL-2, CD4+ CD25+ Foxp3+ Tr cells in the spleen of C57BL/6N mice increased abviously. The ratio of CD25+ Foxp3+ Tr to CD4+ T cells was 24.22%±7.60% in the group of DXM combined with IL-2, while the control group was 4.02% ±0. 84% ( P =0. 01 ). Compared with the control group (0. 14±0.01 ), the ratio of Tr to Te increased obviously in the group of DXM combined with IL-2 (0.43±0. 15 ) ( P = 0.01 ). The group of DXM combined with IL-2 also expressed more glucocorticoid-induced tumor necrosis factor receptor(GITR) and alloreaction was suppressed/n vitro obviously ( P < 0. 05 ). Conclusion DXM amplifies IL-2 induced the proportion of Tr to Te, and suppresses the cell proliferation stimulated by alloge-neic antigen.