摘要
目的在前期已建立日本血吸虫感染兔新模型的基础上,用该血清从噬菌体随机12肽库中筛选阳性单克隆噬菌体,并鉴定其诱导小鼠的免疫保护效果。方法通过给感染日本血吸虫家兔注射酚氧化酶抑制剂,抑制其体内日本血吸虫雌虫产卵,建立无虫卵肉芽肿的日本血吸虫感染动物新模型,用其血清筛选出阳性多克隆噬菌体,经与可溶性虫卵抗原(SEA)免疫兔血清充分吸附后,从中随机挑取14个单克隆分别纯化、扩增,用常规ELISA法检测阳性单克隆噬菌体的抗原性;挑选出与新模型兔血清呈强阳性反应,但与SEA免疫兔血清呈阴性或弱阳性反应的单克隆噬菌体,按1×1015pfu/次剂量,0-2-4周方案,皮下多点注射免疫小鼠。末次免疫4周后,每鼠经腹部皮肤攻击感染(40±1)条日本血吸虫尾蚴,感染42d后观察减虫率及减卵率。结果所选14个单克隆噬菌体均能与新模型兔血清和常规感染模型兔血清反应,尤其是第8号和第13号2个克隆与新模型兔血清呈强阳性反应,但与SEA免疫兔血清呈阴性反应;8号、13号单克隆噬菌体及原始噬菌体肽库免疫小鼠后诱导抗攻击感染的减虫率及每克肝脏减卵率分别为35.81%和63.32%、32.09%和52.02%、14.90%和30.64%。结论阳性多克隆噬菌体与SEA免疫兔血清免疫吸附后能去除大部分表达SEA抗原模拟表位的克隆。
Objective To study the immuno-protective effect against Schistosoma japonicum challenge of the positive monoclonal phages which were screened from the 12 mers-phage random peptide library by the new model rabbit serum. Methods The new model was established by injecting the Schistosoma japonicum infection rabbits with inhibitor of phenol oxidose. Positive clones immunoscreened with the new model rabbit sera were absorbed by SEA immune rabbit sera, and 14 clones selected randomly from them were compared and their antigenic ability was identified by ELISA. The two best positive monoclonal phages (No.8, No.13) recognized by the new model rabbit sera were selected to immunize Kunming mice by subcutaneously injecting 1×10~15 pfu positive phages at 0, 2nd, 4th week respectively. After 4 weeks of the last immunity,each mouse was challenged with 40±1 S.japonicum cercariae. All mice were sacrificed after 42 days and the reduction rates of adult worms and the liver eggs were investigated. Results The positive phage clones after immune absorption were weakly recognized by the SEA immune rabbit sera. The 14 monoclonal phages were recognized by the rabbit sera of the new model and the normal model. Especially No.8, No.13 were strongly recognized by the rabbit sera of the new model,while weakly recognized by the SEA immune rabbit sera. The reduction rates of adult worms and liver eggs induced by the monoclonal phage No.13, the monoclonal phage No.8 and the original peptide library were 35.81% and 63.32%, 32.09% and 52.02%, 14.90% and 30.64%, respectively. Conclusion Most clones of simulated epitopes of SEA can be removed by absorbing positive clones with SEA immune rabbit serum .The 14 monoclonal phages from the new model contain the simulated S.japonicum epitope. The two monoclonal phages have higher reduction rates of adult worms and eggs than original 12 mers-phage random peptide library and the positive polyclonal phages.[
出处
《中国血吸虫病防治杂志》
CAS
CSCD
2005年第1期17-20,共4页
Chinese Journal of Schistosomiasis Control
基金
湖北省科技攻关项目(No.2003AA3003B04)
湖北省卫生厅科研基金重点项目(No.JX1A11)
关键词
日本血吸虫
抗原表位
单克隆
感染
免疫
Schistosoma japonicum
Epitope
Monoclone
Infection
Immunity