Identification of antigenic determinants by polyclonal and hybridoma antibodies induced during the course of infection by vaccinia virus.

In order to extend the understanding of determinants involved in the humoral response in the infected host, mice were subjected to an immunization regimen using both active and uv-killed vaccinia virus. The spectrum of antibody specificity in hyperimmune sera was followed by Western blotting. Comparable studies involving Western blotting and immunofluorescence were conducted with a panel of monoclonal antibodies derived from hybridomas selected from similarly immunized animals. Hyperimmune sera contained circulating antibodies primarily against three polypeptides of 28K, 35K, and 62K. These antigens were shown to be located both at the surface and within the virion. The repertoire of monoclonal antibodies included some that reacted with the 28K and 35K antigens and others that recognized a 32K core complex component or a nonvirion cell surface component, corresponding to the viral hemagglutinin. Within the panel of monoclonal antibodies was a large group which reacted with a 32K antigen found in the IHD-J virion but absent from the IHD-W strain. This finding correlates with the absence of a 32K polypeptide from the IHD-W particle. Overall, the current findings reveal the absence of any particular correlation between the incidence of polyclonal antibodies in the circulation of the immune host and the frequency of selected hybridomas against vaccinia antigens. Application of this type of immunological analysis should provide useful data concerning the detection and mapping of the antigens and their epitopes which are significant for humoral immunity.