CT引导下经皮穿刺活检术在骨骼病变诊断中的应用

目的探讨CT导引下肝细胞生长因子(HGF)基因治疗脑缺血的可行性。方法采用基因重组技术构建携带HGF基因的真核表达质粒,通过脂质体介导法,在CT灌注扫描图像定位下将其多点注射到大鼠急性脑梗死模型的缺血半暗带区域;转染7 d后断颈取脑,切片观察HGF基因于大鼠脑内的表达情况及其生物学效应。结果酶切鉴定及基因测序证实,HGF基因片段已克隆到PIRES2-EGFP的BamH I和Sal I位点之间。HGF基因转染大鼠缺血半暗带区7 d后免疫组化方法证实实验组大鼠转染局部已有HGF表达,血管数量明显多于对照组(P<0.01);CT灌注显示其梗死侧半球的脑血流量高于对照组(P<0.01);TTC染色显示实验组大鼠脑梗死体积小于对照组(P<0.01)。结论脂质体转染HGF基因能够在缺血半暗带区表达,其表达产物能够发挥生物学效应并促进局部侧支循环形成,从而改善脑缺血。

The experimental study of CT-guided hepatocyte growth factor gene therapy for cerebral ischemic diseases

Objectives To investigate the feasibility of CT guided hepatocyte growth factor(HGF)gene therapy for cerebral ischemic diseases.Methods Human HGF cDNA was ligated to pIRES2-EGFP vector.The recombinant plasmid was transfected into the penumbra tissue with liposome,guided by CT perfusion images.After seven days of transfer with recombinant plasmid,the cut sections of rat brain tissues of the treated and control groups were analyzed including immunohistochemistry,vessel count,cerebral blood flow and infarct volume etc.in order to investigate HGF gene expression and biological effect.Results Enzymatic digestion and electrophoresis confirmed that HGF fragments had been correctly cloned into the space between the BamH I and Sal I sites of pIRES2-EGFP.After 7 days of HGF gene transfection,expression of HGF in transfected neurocytes of treated group was observed with immunohistochemistry.The number of vessels in penumbra tissues transfected with HGF vectors and the CBF measured by perfusion CT all were significantly increased than those of the controls(P < 0.01).Simultaneously there was a significant reduction in the ratio of infarct volume as compared with the control group(P < 0.01).Conclusions Liposome/pIRES2-EGFP-HGF complexes can transfect the penumbra tissues and definitely express HGF protein.The HGF gene products can stimulate angiogenesis,promote collateral circulation formation and reduce infarct volume in vivo and therefore is beneficial to the treatment of cerebral ischemia.(J Intervent Radiol,2006,15: 615-619)