细胞凋亡及相关基因bcl-2在大鼠角膜移植物的表达及其意义  

Apoptosis and bcl-2 expression in corneal grafts in rats

作　　者：张永强[1] 陆晓和[1] 曹继强 宫玉波[1] 袁伟[1] 李照峰 唐海亮 

机构地区：[1]南方医科大学珠江医院眼科,广东广州510280 [2]中国人民武装警察8650部队医院,山西晋中030600

出　　处：《中国现代医学杂志》2006年第12期1833-1836,共4页China Journal of Modern Medicine

基　　金：广东省自然科学基金资助;项目编号:04020438

摘　　要：目的探讨细胞凋亡及其相关基因bcl-2与角膜移植急性免疫排斥反应的关系。方法建立大鼠穿透性角膜移植模型。实验分为3组。A组:非手术基本对照组(Wistar);B组:同基因角膜移植组(Wistar→Wistar);C组:同种异体角膜移植组(Wistar→SD)。B、C组分别于术后不同时间(7、10和14d)取角膜植片,细胞凋亡原位末端标记(TUNEL法)检测各组角膜植片细胞凋亡情况,免疫组织化学方法(SABC法)检测植片bcl-2蛋白表达。并以A组正常大鼠角膜做对照。对染色结果采用全自动图像分析系统处理,计算阳性单位PU值。结果正常角膜上皮细胞层仅有极少量凋亡细胞,基质层及内皮细胞层几乎无凋亡细胞;术后1周各移植组(B组,C组)角膜植片各层均可见散在细胞凋亡,与A组相比差异有显著性(P<0.01),B组与C组差异无显著意义(P>0.05);与A组相比,急性排斥期B、C组角膜植片细胞凋亡均增高,且C组增高更明显。正常角膜可见bcl-2蛋白表达,主要存在于上皮层;术后1周各移植组(B组,C组)角膜植片bcl-2蛋白表达轻度减低,与A组相比差异有显著意义(P<0.01);与B组同一时间点相比,急性排斥期C组角膜植片bcl-2蛋白表达明显减低(P<0.01)。结论细胞凋亡在角膜移植急性免疫排斥反应中发挥重要作用,调控基因bcl-2可作为判断急性免疫排斥反应的重要指标。[Objective] To investigate apoptosis and bcl-2 expression and their relationship with corneal graft acute rejection in rats. [Methods] Corneal transplantation was performed orthotopically in Wistar rats and SD rats, All recipients were divided into three groups： group A, nonoperative control （Wistar）; group B, isograft group （Wistar→Wistar）; group C, allograft group （Wistar→SD）. Corneal samples were collected on days 7, 10, 14 postoperatively. Apoptosis was monitored by TUNEL （terminal deoxynucleotidyl transferase mediated deoxyuridine triphosphate nick end labeling）, Immuno-histochemistry was used to detect the expression and distribution of bcl-2 protein in corneal grafts. The corneas of normal Wistar rats were as control. An automatic image analyzer was used to analyze the staining results. [Results] The TUNEL positive cells were present slightly in the epithelium of normal cornea and not present on stroma and endothelium. The TUNEL positive cells of operative groups （group B, C） were scattered in the epithelium, endothelium and stroma of corneal grafts on 7th day postoperatively. Apoptosis of group C increased significantly during allograft rejection in the epithelium, endothelium and stroma of corneal allografts. Bcl-2 were expressed mainly on the normal corneal epithelium. The expression of bcl-2 in corneal grafts decreased on 7th day postoperatively in operative groups （group B,C）; the expression of bcl-2 in group C was markedly decreased during acute rejection in comparison with group B （P 〈0.01）. [Conclusions] The results suggest that apoptosis plays an important role in acute rejection of corneal allograft. Its regulating genes bcl-2 may be important parameter to evaluate the rejection in the corneal allograft.

关 键 词：角膜移植 穿透性 细胞凋亡 BCL-2 

分 类 号：R772.2[医药卫生—眼科]