OBJECTIVETo identify the egg antigens related to the formation of hepatic granulomas and fibrosis of Schistosomiasis japonica.

METHODSThe egg cDNA library of Schistosoma japonicum (S. japonicum) was constructed and screened by immunological methods with the pooled sera of advanced schistosomiasis patients. The inserted foreign DNA fragments of positive clones were sequenced. The sequence data were analyzed using Wdnasis 2.5 and compared with Genebank data using blast software.

RESULTSEighty-one clones containing recombinant DNA fragments were obtained from the egg cDNA library of S. japonicum by immunological screening. The DNA sequences of all clones belonged to the miracidial antigen family. The longest cDNA fragment was 1604 bp, which contained an open reading frame of 351 bp, which encoded a protein of 1 2913.35 daltons.

CONCLUSIONThe cDNA sequence of the miracidial antigen of S. japonicum (Chinese strain) was obtained for the first time.

Animals ; Antigens, Helminth ; genetics ; Base Sequence ; China ; DNA, Complementary ; analysis ; Ovum ; Schistosoma japonicum ; genetics ; immunology