RESUMO
Objective To investigate the effect of regulatory dendritic cells treated by extracorporeal photochemotherapy on T cell proliferation. Methods Human peripheral blood mononuclear cells (PBMCs) were obtained and the immature dendritic cells (imDCs) were induced by recombinant human granulocyte and macrophage colony stimulating factors. SPDCs were obtained by PUVA treatment, and ECDCs were co-cultured with imDCs and PUVA-SP to obtain immunoprecipitated dendritic cells. In vitro, imDCs were co-cultured with SPDCs to obtain SPDCs; imDCs were added to 10ng/ml of LPS, and cultured for 1 day to obtain DCs. The expressions of CD11c, CD83 and CD86 on the surface of the cells were detected. The effect of imDCs on the proliferation of recipient T cells was detected by mixed lymphocyte culture method. Results The early apoptosis rate of PUVA-treated cells was 91.33%. The positive expression rates of CD83 and CD86 in ecpDCs were 22.83%±5.26% and 22.06%±4.37%, respectively, which were similar to those of imDCs (15.06%±0.59%, 15.19%±1.83% (P<0.01), but significantly lower than those in DCs (99.79%±0.36%, 99.85%±0.19%, respectively), the difference was statistically significant (P<0.01). The recipient imDC cells phagocyting the appoptotic splenic lymphocytes from the donor significantly inhibited the proliferation of recipient T cells. Conclusion Apoptosis of splenic lymphocytes induced by extracorporeal photochemotherapy can inhibit the maturation of dendritic cells and inhibit the proliferation of T lymphocytes.
RESUMO
Objective To investigate the effect of infusion of spleen lymphocytes treated by extracorporeal photochemotherapy on the regulatory T cell (Treg)and survival time of skin allograft in mice. Methods The skin allograft model in mice was established with C57BL/6 mice as donors and BALB/c mice as recipients. The spleen lymphocytes (CSP,BSP)in mice C57BL/6 and BALB/c were isolated,and the mice spleen lymphocytes (PUVA-SP) treated with 8-methoxypsoralen plus ultraviolet (PUVA)were prepared. The experimental animals were randomly divided into 5 groups according to the compositions infused into the recipients through vein:PUVA-BSP,PUVA-CSP,BSP,CSP and phosphate buffer solution (PBS)control groups (n=12 in each group). All recipients of each group were injected with PUVA-BSP,PUVA-CSP,BSP,CSP or PBS on day 7 before the operation,on the operation day and day 7 after the operation through the tail vein,respectively. The survival time of graft in the recipients was observed,and the expression of CD4 +CD25 +Foxp3 +Treg in peripheral blood was detected. Results After skin allograft,the rate of CD4 +CD25 +Foxp3 +Treg in peripheral blood of the recipients in PUVA-BSP group and PUVA-CSP group was significantly higher than those of BSP, CSP and PBS control groups. The rate of CD4 +CD25 +Foxp3 +Treg in PUVA-CSP group was higher than that of PUVA-BSP group,while BSP and CSP groups were lower than that of PBS control group. The survival time of skin graft in the recipients in PUVA-BSP group and PUVA-CSP group was significantly longer than that of BSP,CSP and PBS control groups (all P<0.05 ). Conclusions Sufficient infusion of PUVA-SP can induce more CD4 +CD25 +Foxp3 +Treg in the recipients and prolong survival time of skin graft significantly.