在人源抗HBsFab表达载体构建、抗体片段表达及纯化成功后 ,进行放射免疫显像研究 ,以评价其在动物模型中的免疫导向活性。方法 :用13 1I标记人源抗HBsFab ,经腹腔注射 1,3,5 ,7d后行裸鼠人肝癌模型放射免疫显像 ,于第 7天作组织分布测定 ,并以鼠源抗HBsAg单抗为对照进行比较。 结果 :实验组在标记抗体注入后第 3天即获阳性显像 ,第 5天更加清晰 ,此时人源抗HBsFab、鼠源单抗及无关Fab的瘤 /肝放射性比值分别为 5 .4,4.0和 0 .9。结论 :人源抗HBsFab具有良好的导向活性 ,为其用于肝癌的导向治疗提供了实验依据。

Objective: To evaluate the targeting activity in the animal model with human hepatoma, the 131 I human anti HBsAg Fab radioimmunoimaging was explored. Methods: Radioimmunoimagings were taken on different intervals after injection of 131 I human anti HBsAg Fab to the nude mice and tissue distribution was measured. The human anti HBsAg Fab was compared with the murine monoclonal antibodies. Results: The experimental group developed tumor positive images after 3 days of radio labeled monoclonal antibodies injection, and the peak accumulation of radio activity on the 5th day. Statistics indicated the tumor/liver ratio of the human anti HBsAg Fab, murine monoclonal antibodies and the control groups were 5.4,4.0 and 0.9 respectively on the 7th day. Conclusions: Our results suggest that the 131 I human anti HBsAg Fab has a considerable targeting activity, and provide an evidence that it can be used as a novel humanized carrer for targeting therapy of hepatoma.

本项目受国家自然科学基金(39670668)和广州市重点科研项目基金(97-Z-65-02)资助