肝片吸虫分泌排泄抗原及主要多肽对动物模型的免疫保护

IMMUNOPROTECTION OF EXCRETORY/SECRETORY ANTIGEN AND ITS POLYPEPTIDES OF FASCIOLA HEPATICAIn ANIMAL MODELS

体外培养肝片吸虫成虫，制备收集其分泌排泄抗原（ＥＳ抗原）。通过制备性ＳＤＳ聚丙烯酰胺凝胶电泳方法分离纯化分泌排泄抗原中免疫印迹信号最强的两种多肽——１８．６ＫＤ和１７．２ＫＤ多肽。用分泌排泄抗原和两种多肽分别对动物模型进行免疫保护性试验。大鼠和家兔经抗原免疫后，口服攻击新鲜活性肝片吸虫囊蚴，攻击感染的第６０天解剖动物，统计活虫数并计算减虫率。试验结果显示：肝片吸虫的ＥＳ抗原和１８．６ＫＤ及１７．２ＫＤ多肽对动物均有免疫保护作用，其最强的免疫保护率分别为大鼠８１．０４％、８７．９３％、７７．５９％；家兔８０．８８％、８８．２４％、７９．４１％。其中ＥＳ抗原和１８．６ＫＤ多肽免疫保护率较高，１７．２ＫＤ多肽则相对较弱。

おhe adult worms of Fasciola hepatica were cultured in vitro and excretory/secretory antigens were obtainedTwo main polypeptides——186KD and 172KD,which were determined by strong immunoscreening signal using ES antisera,were isolated and prepared with SDSPAGEThe antigens were emulsified with an equal volume of adjuvant,and were injected into rats and rabbits10th day after second injection,the animals were challenged with metacercaria of Fasciola hepatica60 days after the injection,animals were dissected and the number of worms in the animal livers were countedThe results indicate that ES antigen,186KD and 172KD polypeptide can induce animals to produce immunoprotective ability against infection,and that the strongest immunoprotection rate may reach 88%Among the three kinds of antigens,186KD polypeptide showed the strongest immunoprotective ability