取自己制备的纯化人源性抗HBs Fab 片段。用表达的PreS, PreS1, PreS2 蛋白及合成的PreS1 (2147aa)27 肽检测其抗原结合位点。结果显示该Fab 片段在非还原状态下分子量约为54kD, 在还原状态下分解为大小两个片段, 大片段为Fab的Fd 链, 分子量约为28kD; 小片段为Fab 的κ链, 分子量约为26kD。该Fab 片段与PreS及PreS1 蛋白呈现结合反应, 说明其抗原结合位点位于HBsAg 的PreS1 区 Purified human anti- HBs Fab fragment prepared by ourselves. Antigen binding sites were detected using the expressed PreS, PreS1, PreS2 proteins and the synthetic PreS1 (21-47aa) 27 peptide. The results showed that the Fab fragment had a molecular weight of about 54 kD in the non-reduced state and decomposed into two fragments in the reduced state. The large fragment was the Fd chain of the Fab with a molecular weight of about 28 kD. The small fragment was a Fab kappa chain with a molecular weight of about 26kD. The Fab fragment showed a binding reaction with PreS and PreS1 proteins, indicating that its antigen binding site is located in the PreS1 region of HBsAg