目的　研究日本血吸虫 (中国大陆株 ) 2 2 .6 k Da有效抗原表位对小鼠的免疫保护性 ,预测其在抗血吸虫感染中的作用。方法　用纯化的抗 Sj2 2 .6 k Da的多克隆抗体 Ig G对噬菌体 12肽库进行 5轮免疫学筛选 ,挑取克隆 ,经 Western- blot免疫识别、动物初筛及序列分析后 ,将获得的阳性克隆免疫 BABL/ c小鼠。结果　共获得 4个有效抗原表位 ,各免疫组和对照组相比 ,4种表位混合免疫组小鼠 ,获得了 39.5 % (P<0 .0 5 )的减虫率及 5 7.1% (P<0 .0 1)肝总减卵率 ;4种表位分别免疫4组小鼠 ,各组分别获得了 2 7.5 % (P<0 .0 5 )、5 .4% (P<0 .0 5 )、2 2 .8% (P<0 .0 5 )、11.6 % (P<0 .0 5 )的减虫率及 41.4% (P<0 .0 1)、2 9.7% (P<0 .0 5 )、32 .2 % (P<0 .0 5 )、30 .9% (P<0 .0 5 )肝总减卵率。结论　所获得 4种有效抗原表位均可诱导宿主抗血吸虫感染的部分保护力 ,可望为血吸虫疫苗研究增加新的内容 Objective To study the immunoprotective effect of 22.6 kDa antigenic epitope of Schistosoma japonicum (Chinese mainland strain) on mice and to predict its effect on anti-schistosome infection. Methods The phage 12 peptide library was screened by 5 rounds of immunization with the purified anti-Sj2 2 .6 kDa polyclonal antibody Ig G. The clones were picked out and identified by Western-blot, animal screening and sequence analysis. Positive clones were immunized with BABL / c mice. Results Four effective antigenic epitopes were obtained. Compared with the control group, the immunized mice of the four kinds of epitopes achieved 39.5% (P <0. 05) and 5.11% (P < P <0. 0 1). The four kinds of mice were immunized with 4 kinds of epitopes respectively, with 7.5% (P <0.05) and 5.4% (P <0. The worm reduction rates were 41.4% (P <0. 01) and 2 9.7% (P <0. 05) respectively. The worm reduction rates of 11.6% (P < 0. 05), 32.2% (P <0. 05), 30.9% (P <0. 05) of the total liver ejaculation rate. Conclusion All of the four effective epitopes can induce partial protection of host against schistosoma infection, and it is expected to add new contents to schistosome vaccine research