Study on donor antigenic specificity CD4~+CD25~+Treg cells inducing allograft immune tolerance in rats

Objective To study the effects of donator antigenic specificity CD4+CD25+Treg cells on the inducing immune tolerance of transplanted kidney in rats.Methods Constructing allograft kidney transplantation animal moulds with SD rats as donors,while Wister rats as recipients;separating CD4+CD25+Treg cells from Wister rats′ spleens by way of MACS and inducing phenotype of donor antigenic specificity in vitro;detecting the yield and purity of prepared cells by way of FACS.The treatment group(12 cases) moulds were injected CD4+CD25+Treg cells through tail vein at 2,4,6,8,10 weeks after allograft kidney transplantation,while the controls(12 cases) without injection.To observe the mean survival time.To compare the reaction of receptor spleen cells to the donor antigens by way of MTT on 10d,40d,80d postoperative.To detect the level of blood serum creatinine(Cr) on 10d,20d,40d,60d,80d postoperative.Results The yield of CD4+CD25+T cells was 4.13% and purity was 73.34%.The purity of CD4+CD25+Treg cells was 97.1%.The prepared CD4+CD25+Treg cells acquired donor aotigenic specificity with high inhibition ratio to donator antigen at 85.4%.Compared with that in the control,the survival time of transplanted kidney in treatment group was prolonged significantly(P0.05).There was a significant difference between treatment group and controls in responsing of receptors′ spleen cells to donor antigen on 40d,80d postoperative(P0.05).In controls,the level of Cr was significant higher than that of treatment group on 20d,40d,60d,80d postoperative(P0.05).Conclusion Donor antigenic specificity CD4+CD25+Treg cells can specifically suppress recipient immune response to donor antigen and prolong the survival of transplanted kidney significantly.