Abstract: 　Objective To obtain the mimic epitope of specific and sensitive diagnostic antigen in schistosomiasis japonica from phage 12-mer peptide library. Methods Specific Ig was purified from sera of patients with acute schistosomiasis and used to immunoscreen the phage peptide library (PH.D.-12). After 3 rounds of panning, 10 positive plaques were selected and amplified. The immunoactivity of each clone was examined by ELISA. The sensitivity and specificity of immunoactive clones were confirmed by detecting the sera of patients with different parasitosis. Results Six clones could bind to the specific Ig purified from sera of patients with acute schistosomiasis. One clone with the highest A 492 value showed a high sensitivity and specificity. Conclusion The clone (SjA1)identified by the specific Ig from the library played a better part in the immunodiagnosis of schistosomiasis.

Key words: schistosomiasis japonica, phage peptide library, diagnostic antigen