乙型肝炎病毒表面抗原特异性结合肽的筛选与鉴定

目的：筛选并鉴定与乙型肝炎病毒表面抗原（HBsAg ）特异性结合的多肽。方法将酵母表达的HBsAg包被在微孔板上，加入噬菌体进行随机肽库筛选，经过4轮筛选后，随机挑取15个克隆进行DNA测序，并通过夹心ELISA方法鉴定其亲和力，采用剂量依赖结合实验和竞争抑制实验检测其与 HBsAg结合的特异性。结果经过4轮筛选，得到一优势克隆No ．3，展示肽段为SSYAPYVWQPIA ，与 HBsAg有较强的亲和力，剂量依赖结合实验和竞争抑制实验证明克隆No ．3与HBsAg的结合是特异性的。结论利用噬菌体展示肽库技术可以获得HBsAg特异性结合肽，此多肽可以作为靶向分子用于乙型肝炎的基因治疗，为乙型肝炎的靶向基因治疗奠定实验基础。

Screening and identification of HBV surface antigen specific binding peptide

Objective To select and identify the peptide that specifically binds with HBV surface antigen （HB-sAg） .Methods HBsAg dereved from yeast was coated on milipore plate ,phage was added to screen peptide ran-domly .After four rounds of screening ,15 phage clones were selected randomly ,the phage DNA were extracted and sequenced .And their affinities were identified by the sandwich ELISA ,the specificity was identified by the does de-pendent binding test and competitive inhibition test .Results After four rounds screening ,a predominant phage clone No .3 was obtained which could comparatively strong bind with HBsAg ,and this clone displayed a peptide sequence of SSYAPYVWQPIA .HBsAg dose dependent binding test and competitive inhibition test showed that No .3 binding with HBsAg was specific .Conclusion Peptides specifically binding to HBsAg could be obtained through the screen-ing of phage display peptide library .These peptides may be used in target gene therapy of hepatitis B .It will provide experiment foundation of target gene therapy of HBV infection .