^(188)Re直接标记抗人肝癌单克隆抗体片段HAb18的研究

Direct Labeling of Anti-hepatoma Monoclonal Antibody Fragment With ^(188) Re

本工作采用两步法进行 188Re直接标记抗人肝癌单克隆抗体 HAb18片段的研究。用 Sn Cl2 作为 188Re O4 -的还原剂 ,Na HSO3作为单抗片段双硫键的还原剂 ,观察了 188Re O4 -、抗体中双硫键的还原条件及抗体标记对还原率、标记率的影响。标记率为 85%～ 93% ,还原抗体片段巯基数为 2 .4个 /分子 ,免疫活性分数为 0 .91。实验结果表明 :标记物体外稳定性良好 ;标记物在小白鼠和荷瘤裸鼠体内血液清除快 ,并且主要通过肾脏排泄 。

A two steps method of direct labeling of anti human hepatoma monoclonal antibody fragment HAb18 is investigated. Stannous chloride and sodium bisukfite is used as reducing agents of 188 ReO 4 - and antibody fragment respectively. The effects of reduction conditions of 188 ReO 4 - biothiol and antibody on the labeling efficiency is evaluated in detail. The results show that labeling efficiency, numbers of thiol and immunoreactive fraction reached up to 85%~93%, 2.4/molecule and 0.91 respectively. The stability of labeling compounds keep much better in vitro. The biodistribution in normal and nude mice demonstrates that 188 Re Fab′ ( 188 Re F(ab′) 2) is cleared rapidly from the blood and mainly from kidney, and tumor has significant uptake.