Immunoscreening of Schistosoma japonicum cDNA library and cloning of H1 gene

Objective To obtain possible novel cDNA clones coding diagnostic molecules and candidate vaccine for schistosomiasis. Methods The Schistosoma japonicum cDNA library was screened from serum of schistosomiasis patient and some positive clones were obtained.The sequence of insert fragment of H1 clone was determined and analyzed.Based on the results, homology comparison was carried out,and the primers were designed by the insert sequence.PCR method was used to amplify the target fragment,then the product was cloned into pGEM T Results About 7 2×10 3recombinant phages were immunoscreened by anti sera,twelve continuing positive clones were confirmed.H1 gene is composed of 1 186 base pairs,has a 591 bp size complete open reading frame,and is no homologous to Schistosoma japonicum in Genbank.The fragment was successfully amplified by PCR and was cloned into pGEM T vector. Conclusion The results indicate that Sj infection related protective molecules encoding genes obtained by screening Schistosoma japonicum cDNA library can be successfully cloned.It provided the basis for the further study.