Effect Of T Cell Subsets And CD4~+CD25~+ Regulatory T Cells And Foxp3 MRNA In The Acute Rejection Of Kidney Transplantation In Rats

Objective:To investigate the expression and significance of T lymphocyte subsets,CD25+CD4+ regulatory T cells and Foxp3 mRNA in peripheral blood of acute rejection rat after kidney transplantation in rats.Methods:15 cases Wistar rats and 45 cases SD rats were divided into acute rejection group(15 cases SD rats were used as recipient and 15 cases Wistar rats as donors),non-acute rejection group(15 cases SD rats were used as recipient and 15 cases SD rats as donors)and normal control group(15 SD rats as normal control).CD4~+CD25~+ regulatory T cells ratio,Foxp3 mRNA level and renal function were detected on the 7th day after operation,and the acute rejection of renal tissues was detected by histopathological examination.Results:There was no obvious pathological change in the normal control group.4 cases recipients showed borderline change,focal necrosis and interstitial inflammatory cell infiltration,3 cases recipients had acute rejection grade 1,other 8 cases recipients had no obvious pathological changes in non-acute rejection group.The acute rejection group rat kidney showed acute rejection of typical pathological changes,including 2 cases of grade ?,2 cases of grade ?,5 cases of grade ?a and 5 cases of grade?b.According to the rejection grading,Renal pathological picture show:borderline change,focal interstitial infiltration of inflammatory cells,multifocal interstitial infiltration of inflammatory cells,diffuse interstitial infiltration of inflammatory cells and pathological changes in acute rejection group rats.After operation 7 days,the levels of serum creatinine((123.50±8.06)?mol/L),urea nitrogen((7.40±0.75)mmol/L)in acute rejection group were higher than that of the normal control group((49.28±6.85)?mol/L,(3.02±0.67)mmol/L)and non-acute rejection group((107.99±5.73)?mol/L,(6.04±0.84)mmol/L)(P<0.05).The CD3+ T cell ratio((50.68±7.59)%),CD4+ cell ratio((35.81±5.49)%)and the ratio of CD4+/CD8+((2.80±0.22)%)in acute rejection group were higher than that of non-acute rejection group((41.97±9.01)%,(24.89±6.04)%,(1.61±0.14))and control group((39.07±10.91)%,(21.74±6.02)%,(1.43±0.14)%),but CD8+ T cell ratio((11.01±3.30)%)was lower than those of the non-acute rejection group((15.39±4.07)%)and the control group((15.61±4.81)%)(P<0.05).The CD4~+CD25~+ regulatory T cell ratio((.30±0.20)%)and the level of Foxp3 mRNA((0.33±0.08)×10-3)in acute rejection group were lower than that of the non-acute rejection group((2.90±0.40)%,(1.02±0.21)×10-3)and the control group((4.97±0.50)%,(2.13±0.26)×10-3)(P<0.05).Conclusion:The peripheral blood T cell subsets participate in the regulation of acute rejection after renal transplantation.Analysis the change of CD4+/CD8+ ratio is helpful to the early diagnosis of acute rejection and provide the reference for the use of immunosuppressive agents.The occurrence of acute rejection may be related to the decrease of Foxp3 mRNA and CD4~+CD25~+ regulatory T cells.The ratio of CD4~+CD25~+regulatory T cells and the expression level of Foxp3 mRNA in peripheral blood after transplantation were the important indexes to evaluate the immune status of the recipient and to judge the immune tolerance.