The Relation Between CD4~+CD25~+CD127~-T Reg In Human Renal Transplant Recipients And Acute Rejection And The Impact Of Immunosuppressive Therapy On Them

Objective To investigate the relationship of T reg cell levels between acute rejection and immune-suppressive therapy on the basis of the changes of T reg cells in peripheral blood of renal transplant recipients in the near future.Methods The levels of peripheral blood T reg cells were sequentially measured by flow cytometry using anti-CD4,anti-CD25 and anti-CD127 monoclone antibodies in 52 renal allograft recipients(24 male,28 female;6 living-related donor,46 cadaveric donor).At days 1-2 before transplantation samples were obtained and afterwards at days +3 and at weeks +1,+2,+3,+4.All of the recipients were divided into two groups:acute rejection group and stable kidney function group according to whether an acute rejection occurred within the first 4 weeks posttransplant,and divided into two groups:CsA group and FK506 group base on immunosuppressant: steroids+MMF+CsA or steroids+MMF+FK506.We compared the changes of T reg cell levels pretransplant and short courses posttransplant,the changes of T reg cell levels between the acute rejectors and the stables,and the changes of T reg cell levels between CsA group and FK506 group.Results Before transplantation,the levels of T reg cells had no differrence in acute rejection group and normal group(P＞0.05).In the first 3 days after renal transplantation,the levels of T reg cells in stable allograft group soared to the peak,T reg cell levels in acute rejection group also increased but not so much as that high of stable allograft group,so the levels of T reg cells in stable allograft group was significantly higher than that of acute rejection group at the third day after operation(P＜0.05).From the third day to the end of the first week after transplantation,a sharp decrease of the T reg fraction was observed in both groups when majority acute rejection began in the cohort we studied.At the end of the first week after operation, the levels of T reg cells was closest between acute rejection group and stable allograft group,then levelled off in the stable allograft group but remained downward in acute rejection group.There was a relative increase of T reg cell levels in a nonrejector at the end of the fourth week posttransplant,but still kept in low levels in a rejector.Except the level of T reg cells at the first time after transplantation higher than that of before transplantation,all of others are lower than that of before transplantation.There was no obvious statistic difference between the CsA group and FK506 group(P＞0.05).Conclusion The levels of T reg cells in peripheral blood of renal transplant recipients varied at different time in the near future.Detecting the levels of T reg cells was helpful to diagnose acute rejection at early time and to judge prognosis.