大鼠小肠移植术后高迁移率族蛋白1水平变化及原因分析

Serum level changes of HMGB1 in rat small bowel tr.ansplantation model

目的通过观察大鼠小肠移植术后血清及移植肠中高迁移率族蛋白1(HMGB1)的动态变化与病理组织变化,来探讨HMGB1在小肠移植术后变化意义及原因。方法选用近交系SD大鼠与近交系Wistar/A大鼠,建立异位小肠移植动物模型,随机分组。A组:对照组(SD)大鼠36只,仅行开关腹及左肾切除术;B组:同基因移植对照组(供、受体均为SD大鼠)36只;C组:异基因移植组(供体为SD大鼠,受体为Wistar/A)36只。术后2h、12h、1d、3d、5d、7d处死6只大鼠,采血分离血清,同时获取移植肠。酶联免疫法测定血清中的HMGB1及IL-2水平,Westernblot法及RT-PCR法测定移植肠中HMGB1及IL-2的表达水平;同时进行组织病理学检查,观察移植肠的病理变化。结果小肠移植术后能致大鼠血清及肠组织中的HMGB1表达升高。在血清中,B组HMGB1在手术后出现了1次高峰,12h达高峰,而后至术后第3天时下降至正常;C组HMGB1于手术后出现2次高峰,分别于术后12h及术后第5天,与对照组比较差异有统计学意义(P<0.05)。在肠组织中,B组手术后移植物内HMGB1水平略有升高,但与A组相比各时间点差异无统计学意义(P>0.05);但在C组,术后5d,移植物内HMGB1水平明显升高,与A、B组相比差异有统计学意义(P<0.05)。结论小肠移植术后血清HMGB1水平与移植损伤有密切关系,小肠移植术后检测血清中HMGB1水平可能成为一个对预测小肠急性排斥反应的发生及评估急性排斥反应程度的一个潜在、有用的指标。

Objective To detect serum level and histopathological changes of high mobility group box protein 1（HMGB1） in rat small bowel transplant recipients,and to explore the role of HMGB1 in injury after small bowel transplantaion.Methods A Heterotopic small bowel transplantation model was established using inbred SD and Wistar/A rats.The rats were randomly divided into three groups.Group A rats（SD rats,n=36） only received left kidney resection.Group B rats（Syngenic SBT group,SD rats,n=36） served as isograft control group.Group C rats（heterogenic SBT group,n=36） were employed as donors and Wistar/A rats as recipients.Six rats in each group were killed at 2 hours,12 hours,1day,3days,5 days and 7 days after the operation respectively.The blood and graft samples were harvested for further study.The serum level of HMGB1 and IL-2 were determined by ELISA,while HMGB1 and IL-2 in intestinal grafts were detected by Western blot and RT-PCR.Pathological changes of the intestinal grafts were also observed at indicated time point.Results HMGB1 expression increased in serum and in intestinal tissue after small bowel transplantation.In group B,HMGB1 level peaked at 12 hours after operation,which recovered to normal level at day 3 after operation.In group C,HMGB1 serum level increased after operation,two peaks were observed at 12 hours and day 5 after operation.It was significantly different from that of the control group（P0.05）.In group B,the expression of HMGB1 in intestinal grafts increased,but no significant difference was seen between groups A an B at the indicated time point（P0.05）.,The expression of HMGB1 in intestinal grafts increased at day 5 after operation in group C,but no significant difference was observed compared to groups A and B（P0.05）.Conclusions HMGB1 serum level is closely related to graft injury after transplantation of the small bowel,and it might be a potential indicator in predicting small bowel acute rejection and in evaluating the degree of acute rejection.