摘要
目的探讨 PD-L1.Ig 联合1,25(OH)_2D_3对大鼠胰腺移植急性排斥反应的免疫调控作用以及对大鼠移植胰腺存活时间的影响。方法以 F344大鼠为供体,Lewis 大鼠为受体,建立4组原位胰腺移植模型。每组12例,共48例。A 组:对照组、B 组:PD-L1.Ig 组、C 组:1,25(OH)_2D_3组、D 组:PD-L1.Ig+1,25(OH)_2D_3组;观察术后各组血糖变化,移植物存活以及组织病理学改变;流式细胞检测受体血、脾以及移植胰 CD4^+T 细胞、CD8^+T 细胞、CD4^+CD25^+T 细胞表达水平;酶联免疫吸附试验(ELISA)检测移植物局部白细胞介素(IL)-2、-4、-10、-12表达水平;于术后第7天分别杀死各组受体和供体鼠各2只,取受体脾细胞与供体作混合淋巴细胞反应(MLR)。结果与A比较,PD-L1.Ig 组并未显著延长移植胰腺存活时间(P>0.05),C、D 组对改善血糖水平和延长移植胰腺存活时间作用明显(P<0.01),其中,D 组移植胰腺存活时间最长(23.9±0.8)d;与 A 组比较,B 组无明显改善,C 组排斥反应较 A 组明显减弱,而 D 组几乎未发生排斥反应;CD3^+CD8^+T细胞计数 D、C、B 与 A 组比较均有减少,差异有统计学意义(P<0.01)。CD4^+T 细胞 D、C、B 与 A 组的差异有统计学意义(P<0.05)。CD4^+CD25^+调节性 T 细胞 A、B、C、D 组逐渐升高,差异有统计学意义(P<0.01),且以 D 组较为明显(C 组比 A 组 P<0.01);D 组明显抑制移植物局部 Th1型细胞因子 IL-2、IL-12的产生,显著提高 Th2型细胞因子 IL-4、10的水平;与对照组比较,各治疗组受体T淋巴细胞在 MLR 中表现对供体淋巴细胞特异性低反应性,能有效抑制 T 细胞对同种异体抗原的反应。结论共刺激阻断剂 PD-L1.Ig 联合1,25(OH)_2D_3可有效抑制细胞免疫应答,干预急性排斥反应,显著延长大鼠移植胰腺存活时间。
Objective To investigate the effects of PD-L1. Ig combined with 1,25 （OH）2D3 on the acute rejection of pancreatic allograft in the rat model, and the synergic effects of them in prolonging survival time of vascularized pancreatic allograft. Methods Pancreatic allograft from F344 rats was transplanted to Lewis recipients. Experimental animals were randomly divided into 4 groups, 12 rats for each： group A （negative control） ; group B （intraperitoneal injection of PD-L1. Ig on day 0,2 and 4 after pancreas transplantation）; group C （allograft recipients receiving daily intraperitoneal injection of 1,25-dihydroxyvitamin D3） ; group D （ allotransplantation and a combination of intraperitoneal PD-L1. Ig and 1, 25-dihydroxyvitamin D3 ）. The blood glucose in the recipients, the pathological changes of the allografts and the survival of pancreatic allografts were observed. The peripheral blood, spleens and grafts were harvested from the recipients for determination of CD3^＋ CD8^＋ T cells ,CD4^＋ T ceils and CD4^＋ CD25^＋ T by flow cytometry. After transplantation,the level of graft interleukin -2,4,10,12 in the recipients was determined by ELISA kit analysis. The mixed lymphocyte reaction （MLR） of the donors with the recipient spleen cells was performed. Results Comparing with group A, allografts survival time was not significantly prolonged in group B （P 〉0.05） ,which in groups C and D,the recipient survival time was significantly prolonged and blood glucose level significantly reduced. The survival time of pancreas grafts was longest in group D. The number of CD3^＋ CD8^＋ T cells and CD4^＋ T cells was decreased in groups B, C and D as com-pared with group A （P 〈 0.01 ）. Concentration of Thl-type cytokine in allograft decreased markedly, Th2 cytokine increased significantly. The donor-specific MLR was suppressed in spleen cell cultures. Conclu- sion Combined use of PD-L1. Ig and 1,25-dihydroxyvitamin D3 may suppress the cell-mediated immune responses and pancreas allograft rejection effectively and promote further prolongation of the survival of pancreas allografts.
出处
《中华实验外科杂志》
CAS
CSCD
北大核心
2007年第12期1537-1539,共3页
Chinese Journal of Experimental Surgery
关键词
胰腺移植
排斥反应
免疫
Pancreas transplantation
Rejectio
Immune
