Production of monoclonal antibody to characterize the antigen of Paragonimus westermani.

We produced monoclonal antibodies against the adult antigen of Paragonimus westermani to investigate the expression of the stage-specific antigen of adult flukes. Two hybridoma cell lines, A1-2 and A4-1, were established. A1-2 reacted specifically only with the adult antigen in an enzyme-linked immunosorbent assay (ELISA), whereas A4-1 reacted with both adult and larval antigens. By immunoblotting analysis, A1-2 was found to react with four bands with molecular weights of 35,000, 17,000, 15,500, and 12,500 in the adult antigen but with none in the larval antigen. A4-1 was found to bind to the band of 27,000 daltons in the adult antigen as well as those of 28,000 and 26,000 daltons in the larval antigen. By immunohistochemical methods, a positive reaction was observed only in the parenchymal tissues of the adult flukes with A1-2. A4-1 reacted with the substance that located on the gut epithelium and in the luminal contents of both the adult and larval flukes. These results indicate that the adult P. westermani possesses an antigen or antigenic determinant specific to the adult stage, as well as that common to both the larval and adult stages.