腺病毒介导的TIMP-4基因转染抑制血管损伤后新生内膜形成

目的 :应用腺病毒介导的转基因方式转染人组织型金属蛋白酶抑制剂 4 (TIMP 4 )基因 ,以观察TIMP 4对球囊损伤后新生内膜形成的影响。方法 :体外培养血管平滑肌细胞 (VSMC)并转染含有TIMP 4基因的重组复制缺陷型腺病毒载体 (AdTIMP 4 ) ,采用单层培养细胞刮片法 ,观察TIMP 4对细胞迁移的影响 ;以大鼠颈总动脉球囊损伤模型为研究对象 ,损伤后即刻经血管外膜分别转入盐水、空载腺病毒载体和含有TIMP 4基因的腺病毒载体 ,观察细胞迁移和新生内膜形成情况。结果 :培养的VSMC转染AdTIMP 4后 ,细胞迁移明显受到抑制 ,与对照组相比抑制率为 6 3.9% (P <0 .0 1) ;在大鼠颈总动脉球囊损伤模型中 ,转基因后 4d时生理盐水组、空载腺病毒组和转染AdTIMP 4组内弹力板内的细胞数依次为 (32 .5± 4 .8)个细胞、(33.8± 7.0 )个细胞和 (8.2± 2 .4 )个细胞 ,转染TIMP 4可以显著抑制血管损伤后细胞向内膜的迁移 ;血管损伤后 2 8d时 ,转染TIMP 4组新生内膜面积与中膜面积比值与对照组相比降低了 6 6 .5 % (P <0 .0 1) ,空载腺病毒组与生理盐水组之间差异无显著性。结论 :TIMP 4可以抑制培养的VSMC的迁移 ,局部干预可以明显抑制大鼠颈总动脉球囊损伤后细胞的迁移和血管新生内膜的形成。

Adenovirus-mediated transfer of TIMP-4 gene inhibits neointimal formation after balloon injury

OBJECTIVE: To investigate the effects of human tissue inhibitor of matelloproteinase-4 (TIMP-4) on vascular smooth muscle cells (VSMCs) migration and the neointimal formation after balloon injury in rats. METHODS: The cultured VSMCs were transfected with an adenoviral vector containing human TIMP-4 gene, AdTIMP-4. Effect of TIMP-4 on VSMC migration was investigated by monolayer cell scrape. AdTIMP-4, control adenoviral vector or PBS was transduced into the rat carotid artery from the adventitial after carotid artery injury. Cell number within the internal elastic lamina 4 days after gene transfer was counted and neointima/media area ratio 28 days after gene transfer was calculated. RESULTS: The migration distance of VSMCs infected with AdTIMP-4 was inhibited markedly. Morphometric analysis demonstrated a statistically significant reduction in the number of cells migrated into neointima compared with controls [(32.5 +/- 4.8) cells per section, (33.8 +/- 7.0) cells per section and (8.2 +/- 2.4) cells per section for uninfected, AdGFP-treated and AdTIMP-4-treated arteries, respectively]. There was a reduction of intima/media ratio of TIMP-4-treated group by 66.5% compared with control groups 28 days after gene transfer (P < 0.01). There was no statistical difference between the control adenoviral vector group and PBS group. CONCLUSION: Adenoviral mediated gene transfer of TIMP-4 inhibits migration of VSMC and significantly reduces neointimal hyperplasia in the rat carotid balloon injury model. The TIMP-4 gene transfer is a potential therapeutic approach to preventing neointimal formation after balloon injury.