Development of monoclonal antibodies against group A animal rotaviruses

Hybridomas secreting monoclonal antibodies (MAbs) to a group A rotavirus (GAR) were developed by fusion of myeloma cell (SP2/0) with spleen cells of BALB/c mice immunized with semi-purified bovine rotavirus (CR129, G10P11). Two of these rotavirus-specific monoclonal antibodies were further characterized by immunoblotting and also tested for their reactivity with rotaviruses of bovine, equine and porcine origin in a sandwich ELISA. MAb 6C7F7 (IgM isotype) showed reactivity with two proteins i.e. VP2 (95 kDa) and VP6 (44 kDa), while MAb 2H7E8 (IgG2b isotype) reacted with only 44 kDa VP6 protein of purified bovine rotavirus CR129 on immunoblotting. These VP6-specific MAbs were used as capture antibody in sandwich ELISA for testing with different group A rotavirus antigens. Both MAbs reacted equally with all the bovine and equine rotavirus isolates tested and also with two known rotavirus positive porcine stool samples. These findings suggest that one of these MAbs is directed specifically against a group-specific protein VP6 and will be useful to detect group A rotaviruses directly from stool samples in different animal species employing a sandwich ELISA.