ABSTRACT
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.
Subject(s)
Animals , Antibodies, Helminth/immunology , Antibodies, Monoclonal/immunology , Antibody Specificity , Antigens, Helminth/immunology , Cross Reactions , Fasciola/immunology , Immunoenzyme Techniques , Mice , Mice, Inbred BALB CABSTRACT
Two monoclonal antibodies (McAbs) were produced from BALB/c mice hyperimmunized with tegumental extract of Schistosoma japonicum (Chinese strain). The two McAbs were characterized with regard to antibody isotype, antigen binding specificity and parasite stage specificity. One McAb, 8G9-5, was identified as IgM, whereas the other McAb, 9E7, was determined to be IgG2a. Immunoblotting assay indicated that McAb 8G9-5 binds strongly to the band of tegumental antigens of Mr 64 kDa but also binds weakly to other bands at 116, 105, 97, 54, 50, 47 and 45 kDa, whereas 9E7 McAb reacts specifically at Mr 54 kDa. Anatomical localization of the antigens in the adult worm by indirect immunofluorescence assay indicated that the target epitopes of McAb 8G9-5 are in the intra-tegumental structure, whereas the McAb 9E7 epitope is on the surface membrane. The two McAbs also react at similar sites within the teguments of schistosomula and lung worms.