同种带瓣主动脉移植应用免疫抑制治疗的实验研究

Experimental study of immunosuppressive treatment in rat aortic valved homograft.

目的 探讨免疫抑制治疗在减轻排斥反应、改善同种带瓣主动脉 (AVH)移植远期疗效中的作用。方法 成年Wistar大鼠为供体 ;36只SD大鼠为受体 ,随机分为 3组 ,每组 12只。A组 :术后接受 1∶10稀释树突状细胞 (DC)单克隆抗体 (单抗 )治疗。B组 :术后接受 1∶2 0稀释DC单抗治疗。C组 :术后无特殊处理 ,为对照。A、B组分别于AVH移植后次日起接受DC单抗 (0 2ml腹腔隔日注射 )治疗 ,共2周。各组术后 2、4、8、12周测定ICAM 1、TCR αβ、CD4 0 /CD4 0L的表达 ,行标本组织病理学观察。结果 与对照组相比 ,术后 2～ 4周A组ICAM 1的升高、术后 2周CD4 0 的表达均明显减轻 (P <0 0 5 )。A、B 2组术后 2周TCR αβ的表达均低于对照组 ,且A组第 4周仍明显低于对照组 (P <0 0 5 )。病理观察显示 :A组术后各时间段病理损害程度均明显轻于对照组 ,病理改变出现时间延迟。B组病理改变程度介于A组和C组之间。结论 AVH移植术后早期应用DC单抗可抑制免疫排斥反应 ,减轻术后病理损害。DC单抗的作用呈明显的量效关系。

Objective: To evaluate the effect of immunosuppressive treatment on aortic valved homograft(AVH) durability. Methods: Rat AVHs were heterotopically allografted onto abdominal aorta from Wistar to SD rats. 36 SD rats were divided into 3 groups (12 rats in each group). Group A and group B were treated with DCmAb diluted by 1∶10 and 1∶20 respectively within 2 weeks after transplantation. Group C served as control. The animals were sacrificed in batches at 2,4,8and 12 weeks postoperatively. Blood samples and AVH specimens were obtained for assessing ICAM 1, TCR αβ, CD 40 ,CD 40L , and histological studies. Results: Compared with controls the TCR αβ expressions at 2 weeks were significantly reduced in group A and group B. The ICAM 1 expressions at 2 and 4 weeks were also reduced in group A. The CD 40 expressions were reduced at 2 weeks in group A, and the CD 40L at 2 weeks was reduced in both experimental groups when compared with control group. There was no significant difference befween CD 40 and CD 40L expression in group A and group B. Histological studies showed a similar significant mitigation of rejection response in group A. The histological changes were serious in group B than that in group A. Conclusion: DCmAb treatment at early stage after transplantation may inhibit the immune response, and reduce the pathological damage in AVH.