Contents of Volume 31

Abstract

We used the protein blot radioimmunoassay technique (Smith and Summers, 1981) to evaluate the immunoreactivity of antisera made against SDS-disrupted baculovirus structural proteins. Eight antisera (six for NPVs and two for GVs) were tested against eleven nuclear polyhedrosis (NPV) and six granulosis viruses (GV). Homologous reactions revealed that SDS-disrupted baculovirus antigens elicited antibodies which reacted with several of the virus proteins.Heterologous reactions of each viral antiserum were determined with a total of 17 baculoviruses. Using these data and that of Smith and Summers (1981), we were able to detect a number of shared antigenic determinants which revealed some specific serological relationships among some of the 17 viruses tested. The MNPVs showing distinct serological relatedness included those of Autographa californica, Rachiplusia ou, Anticarsia gemmatalis, Choristoneura fumiferana, and Orgyia pseudotsugata. Heliothis armiger MNPV and Heliothis zea SNPV shared cross-reacting antigenic determinants as did Trichoplusia ni SNPV, Pseudoplusia includens SNPV, and Heliothis zea SNPV. The GVs. of T. ni, H. armiger, and Spodoptera frugiperda were also serologically related. Also reactions were detected which indicated the presence of common antigenic determinants among different baculovirus subgroups in addition to those originally detected in our earlier study (Smith and Summers, 1981).Because of the large number of structural proteins in baculoviruses and the lack of information concerning their structural or functional roles in the virus group specific antigenic determinants could not be identified. However, protein blot RIA allows specific identification of baculoviruses and the number and molecular weight of homologous and heterologous proteins sharing antigenic determinants.