Donor antigenic specificity CD4+CD25+Treg cells prolong the survival of allograft kidney in rats / 中国组织工程研究

ABSTRACT

BACKGROUND: the development of magnetic separation technique,it is feasibility to in vitro sort and amplify CD4+CD25+Treg cells for transplantation; however,the application dosage and immune tolerance have been less reported yet.OBJECTIVE: To investigate dose-effect relationship of CD4+CD25+Treg cells during allograft transplantation.METHODS: SD rats which were considered as the donors and Wistar rats as receptors were used to establish allograff kidney transplantation models.CD4+CD25+Treg cells were separated from splenic cells of Wistar rats and induced phenotype of donor antigenic specificity in vitro.According to the quantities of CD4+CD25+Treg cells injecting through tail vein during the operation of allograft kidney transplantation,models were rolled into four experiment groups group 1(2×105),group 2(5×105),group 3(1×106),and group 4(2×106).The models out injection were considered as controls.Survival status of kidney was detected at day 15 postoperatively; creatinine level and pathological changes were detected at days 4,9 and 15 according to Banff Schema diagnostic standard; semi-quantitative scores were measured Watanabe technique.RESULTS AND CONCLUSION: The death rate was the highest in control group(83.3%),and then group 1(66.7%),group 4(58.3%),and group 2(33.3%); but rats in the group 3 were all survival.Creatinine level in experimental groups was significantly less than control group at days 4,9,and 15 postoperatively(P<0.05,P<0.01); the creatinine levels in the group1 and group 2 were significantly greater than in the group 3 and group 4 at days 9 and 15 postoperatively(P<0.05),Semi-quantitative scores demonstrated that there was no significant difference between group 2 and group 1; but the scores in the group 3 and group 4 were significantly greater than control group(P < 0.05).The results indicated that CD4+CD25+Treg cells could improve kidney function following transplantation,and prolong survival time of transplanted kidney.The 1×106 was the best dosaae for application.