rAAV-CD151-AAA^194-196表达对大鼠缺血后肢血管新生的影响

Effect of rAAV-CD151-AAA^(194-196) Expression on Angiogenesis of Rat Ischemia Hind-Limb

目的观察CD151及其突变体在大鼠后肢缺血模型中的表达以及对血管新生的影响,进一步研究CD151促血管新生的分子机制。方法将实验大鼠随机分组,分别给予生理盐水,rAAV-GFP,rAAV-CD151和rAAV-CD151-AAA194-196(整合素α3/α6结合缺陷突变体),分点注射至大鼠左后肢肌肉组织内,基因转染1周后行股动脉切除术建立大鼠后肢缺血模型,假手术组不切除股动脉。建模5周后测定后肢皮肤温度,检测缺血肌肉组织毛细血管密度,Westernblot检测各组大鼠缺血肢体局部CD151的表达。结果术后5周,rAAV-CD151和rAAV-CD151-AAA194-196组的CD151蛋白及AAA194-196突变体蛋白表达水平明显高于其余各组(均P<0.05),rAAV-CD151和rAAV-CD151-AAA194-196两组间蛋白水平无明显差别,但rAAV-CD151-AAA194-196组大鼠缺血后肢平均皮肤温度和毛细血管密度明显低于rAAV-CD151组(均P<0.05)。结论研究证实CD151促血管新生是通过生成CD151-整合素α3/α6复合体而实现的,CD151-整合素α3/α6复合体的形成是CD151促血管新生的始动机制。

Objective To investigate the effects of CD151 and CD151 mutant gene delivery on angiogenesis in the model of rat hind-limb ischemia. Methods Rats were randomly divided into 5 groups.Four groups were injected with saline,rAAV-GFP,rAAV-CD151,or rAAV-CD151-AAA194-196 respectively（n=6 each）.After 1 week of transfection,the femoral arteries of the rats were excised to establish the model of left hind-limb ischemia.Sham-operated animals underwent the same surgical procedure without femoral artery resection.The skin temperature of the hind-limb was measured and the capillary density of the ischemic muscle was observed by immunochemical staining for anti-CD34 antibody.The expression of CD151 in the ischemic tissue was detected by Western blot. Results The expression of CD151 and CD151 mutant protein was increased significantly in rAAV-CD151 and rAAV-CD151-AAA194-196 groups as compared with other groups.There was no significant difference in the expression between the rAAV-CD151 and rAAV-CD151-AAA194-196 groups（P0.05）.The average skin temperature and the capillary density in rAAV-CD151 group were higher than those in rAAV-CD151-AAA194-196 group. Conclusion The results suggest that CD151 associates directly with α3/α6 integrins to form a functional complexes,thus promotes angiogenesis.