四株抗细粒棘球蚴囊液抗原单克隆抗体的免疫印渍分析

Immunoblot Analysis of Four Monocional Antibodies Against Cyst Fluid Antigens of Echinococcus granulosus

本文报告了应用免疫印渍法(Western Blot)分析2F1、2F10、2G4和 D5四株抗细粒棘球蚴囊液抗原的单克隆抗体的实验结果。用浓缩人肝细粒棘球蚴囊液经 SDS—PAGE 电泳分离后,转印硝酸纤维膜。用4株单克隆抗体识别的结果表明。2F1识别的抗原表位存在于分子量为38kDa,28kDa、20kDa 和14kDa 的多肽链上;2F10识别的抗原表位存在于38kDa、28kDa 的肽链上,38kDa 的反应带很淡,说明这一肽链上2F10抗原表位的密度很低;2G4仅识别位于38kDa 上的抗原表位;而 D5则识别的主要是28kDa、20kDa 和14kDa肽链上的抗原表位。这一结果说明这4株单克隆抗体是针对不同抗原表位的抗体,而2F1识别的抗原表位较广泛地存在于分子量范围较广的不同肽链上,应当是细粒棘球蚴囊液的主要抗原表位。实验结果还表明同一种抗原表位存在于被划分为抗原5和抗原 B 的不同肽链上。因而对至今公认的细粒棘球蚴囊液的主要抗原为抗原5和抗原 B 的概念提出了新的看法,这对于今后细粒棘球绦虫抗原的研究可能有重要意义。

This paper reports the experimental resuhs of immunoblot analysis of four monoclonal antibodies(McAb)2F1,2F10,2G4 and D5 against cyst fluid antigens of Echinococcus granulosus.Concentrated cyst fluid of E.granulosus from human liver,after separation by SDS-PAGE,was transprinted on nitrocellulose membrane.The results of recognition by the four McAbs showed that antigenic epitopes recognized by 2F1 existed on polypeptide chain with molecular weights of 38 kDa,28 kDa,20 kDa and 14 kDa;that antigenic epitopes recog- nized by 2F10 were on polypeptide chain of 38kDa and 28kDa,with a very pale reaction zone on 38kDa peptide chain,indicating the very low density of the epitope to 2F10 on this peptide chain;that 2G4 recognized only antigenic epitope located on 38kDa peptide chain,a finding which was consistent with the results of blocking test of the above three McAbs;and that D5 recognized epitopes on 28kDa,20kDa and 14kDa polypeptide chain,with a very pale reac- tion zone on 38kDa peptide chain as well.These resuhs demonstrated that these four McAbs were those directed against different antigenic epitopes.Antigenic epitopes recognized by 2F1 widely exist on different peptide chains with extensive range of molecular weight and therefore should be the principal antigenic epitopes of E.granulosus. According to the theory that one monoclonal antibody recognizes one antigenic epitope, results of the present study showed that the same antigenic epitope existed on different pep- tide chains divided into antigen 5 and antigen B.New ideas are put forward on the generally recognized concept that the principal cyst fluid antigens of E.graulosus are antigen 5 and antigen B,and the authors hold that these ideas might be of significance to further studies on E.granulosus antigens.