人ATP7B基因对Wilson病动物模型LEC大鼠肝硬化及肝癌的治疗

GENE THERAPY FOR HEPATIC CIRRHOSIS AND HEPATOMA IN LEC RAT BY INTRODUCING HUMAN ATP7B cDNA

目的 探讨人ATP7B基因对Wilson病动物模型LEC(Long EvansCinnamon)大鼠肝硬化及肝癌的治疗效果。 方法 将 7 1kb含有鸡 β肌动蛋白启动子的人正常ATP7BcDNA ,经显微注射法导入Wilson病动物模型LEC大鼠受精卵 ,建立转基因功能恢复大鼠模型。以无转基因大鼠及正常野生型LEA大鼠为对照 ,对 17～ 30周龄的转基因大鼠的血清AST、ALT水平进行连续测定 ,同时取 30和 6 0周龄转基因大鼠的肝脏进行病理组织学和组织化学分析。 结果 17～ 30周龄 ,转基因大鼠的血清丙氨酸氨基转移酶 (AST)、天门冬氨酸氨基转移酶 (ALT)保持在较低的水平。至 6 0周龄 ,雄性转基因大鼠肝组织未见胆管纤维化。在所有被检的转基因大鼠个体未见肝细胞癌性病变。转基因大鼠的存活率达 95 7%。此外 ,30和 6 0周龄的转基因大鼠肝细胞内铜着色颗粒的分布及数量无明显变化。 结论 人ATP7B的导入有效的延缓了Wilson病动物模型LEC大鼠肝硬化的形成、抑制了肝癌的发生。Wilson病的肝硬化及肝癌的发生可能与铜的蓄积无直接关系。

Objective To investigate the possibility of affecting transgenic therapy for the hepatic cirrhosis and hepatoma in Wilson disease by human ATP7B cDNA. Methods The 7.1*!kb transgene consisting of human ATP7B cDNA and chiken β-actin promoter was introduced into the LEC rats which is an animal model of Wilson disease by microinjection.The plasma AST and ALT activities in transgenic rats were measured continuously from weeks 17 to 30 using non-transgenic and LEA rats as controls.The histological and histochemistry changes of liver in the transgenic rats at 30 and 60 weeks of age were examined. Results The plasma AST and ALT activities in transgenic rats were kept at the relatvie lower levels from 17 to 60 weeks of age, as compared to the age-matched non-transgenic rats.By the age of 60 weeks,none of the transgenic males developed cholangiofibrosis or hepatoma,whereas all of the non-transgenic rasts had severe cholangiofibrosis at the age of 30 weeks and one male rat had hepatoma at 60 weeks.The transgenic rats were phenotypically normal,and the survival rate was 95.7%.In addition,the distribution and the numbers of the granules of stained copper in the hepatocytes of the transgenic rats did not show any significant difference between 30 and 60 weeks.Conclusion The human ATP7B successfully delayed the onset of hepatic cirrhosis,and suppressed the development of hepatoma in the LEC rats by gene transfer.The hepatic cirrhosis and hepatoma in Wilson disease may be not directly related to the copper accumulation.