Development and characterization of monoclonal antibodies against excretory-secretory antigens of Fasciola gigantica.

Monoclonal antibodies (MAbs) directed against Fasciola gigantica excretory-secretory (ES) antigens were developed from BALB/c mice. Four were selected for further study, from the panel of hybridomas. The antigen specificities of these MAbs were characterized and localized by enzyme-linked immunoeletrotransfer blot (EITB) and immunoperoxidase technique. The target epitopes of these MAbs are 66 kDa protein (MAb 2D10), 66 and 27-26 kDa proteins (MAbs 5D10 and 4F5) and 27-26 kDa protein (MAb 2D9). MAb 2D9 reacted to the antigenic components of the luminal content and epithelial cell lining the cecum, whereas MAb 2D10 reacted specifically to the antigens of the tegument and surface membrane. It was found that all MAbs cross-reacted to various degrees with the antigens extracted from Schistosoma mansoni, S. mekongi, S. spindale and Paramphistomum spp. However, when MAbs were diluted to 1:100 or 1:400 significant reduction of their cross-reactivities was observed.