ABSTRACT
<p><b>OBJECTIVE</b>To investigate the effect of the different immunosuppression therapy on CD4(+)Foxp3(+)regulatory T cells (CD4(+)Foxp3(+)Treg cells) in the peripheral blood monocytes of kidney transplantation recipients.</p><p><b>METHODS</b>A Closed Cohort study was conducted in 50 primary living kidney transplant recipients between January 2006 and January 2008, who had been followed up for 1 year. The recipients divided into calcineurin inhibitors group (CNI + MMF + Pred) (19 recipients, including cyclosporin group 10 recipients and tacrolimus group 9 recipients), rapamycin group (RAPA + MMF + Pred) (31 recipients). Twenty end-stage renal disease patients were in control group. The frequency of CD4(+)Foxp3(+)Treg cells in total CD4(+)T cells was analyzed by flow cytometry in peripheral blood from three groups, results were compared.</p><p><b>RESULTS</b>The clinical variables of recipients such as age, sex, cold ischemia time, human leucocyte antigen mismatch, panel reaction antibody, rejection episode were no significant difference. The percentage of CD4(+)Foxp3(+)Treg cells in total CD4(+) cells was significantly higher in rapamycin group and end-stage renal disease group than calcineurin inhibitors group (P < 0.01). The level of CD4(+)Foxp3(+)Treg cells between cyclosporin group and tacrolimus group was no significant difference (P > 0.05).</p><p><b>CONCLUSION</b>The level of CD4(+)Foxp3(+)Treg was significantly higher in patients receiving RAPA + MMF + Pred than the patients receiving CNI + MMF + Pred, which suggested that RAPA may be play a more important role in immune tolerance induction.</p>