人抗 HBsAg 噬菌体抗体 Fab 段基因的序列分析及表达

Sequence analysis and expression of anti HBsAg phage antibody Fab gene

对已建的噬菌体抗体库分离出来的人抗ＨＢｓ克隆进行了序列分析和表达研究，发现４个克隆中有３个克隆的重链和轻链完全相同。ＤＮＡ序列分析表明，ＶＨ分别属于ＶＨⅠ亚群和Ⅲ亚群，其轻链ＶＬ分别属于ＶλⅡ亚群和ＶλⅠ亚群。构建了可溶性Ｆａｂ段表达载体，显示出在细菌中表达的Ｆａｂ段抗体与ＨＢｓＡｇ特异性结合，这说明所筛选出来的噬菌体抗体具有抗ＨＢｓＡｇ的特异性。

Human anti HBs clones isolated from phage antibody library were analysed with DNA sequencing and expressed. Three of four clones had the same sequence of heavy and light chains. The V H genes were derived from V HⅠ and V HⅢ,V Ls belonged to V λⅡand V λⅠ with DNA sequencing. Soluble Fab which was expressed in the periplasm of E. coli showed specific binding to HBsAg. These suggest that the phage antibodies are specific anti HBsAg.