摘要
选用无毒、无免疫原性的高分子化合物聚乙二醇(PEG)为修饰剂,以活性酯法制备出PEG- 重组人超氧化物歧化酶(PEG-rh SOD)共价结合物.修饰酶的生物半衰期为15h,比修饰前延长了90倍,对酸、碱、热的耐受力明显高于修饰前.用照射小鼠的活存率评价了PEG-rhSOD的辐射防护作用.小鼠受8.5Gy γ射线照射前1h腹腔注射30万U/kg PEG-rh SOD,可提高活存率42%,与未修饰的rhSOD相比,活存率提高14%.实验仍在进行中.
Recombinent human CuZn SOD (rhCu/Zn SOD) was covalently linked with activated polyethyleneglycol (PEG) ,a kind of nontoxic ,nonimmunogenic and biocompatible polymer. The modified enzyme,PEG-rhCu/Zn SOD,Has longer half-life (15 h). Its abilities to resist acid, alkali and heat were increasedsignificantly. Mice given PEG-rhCu/Zn SOD 1 h before irradiation had higher survival rate than thosenot given or given rhCu/Zn SOD after they were exposed to whole body r-ray irradiation at doses of 8.5Gy.
关键词
超氧物歧化酶
研制
辐射保护剂
<Keyword>Radioprotective agent Superoxide dismutase Genetic engineerihg Chemical modification
