title: Antigenic and immunogenic analysis of group A and group B respiratory syncytial virus G proteins expressed from recombinant baculoviruses.
abstract: The attachment glycoprotein G plays a major role in the antigenic variability of respiratory syncytial (RS) virus. We have expressed from recombinant baculoviruses antigenic group A and group B RS virus G proteins (designated bacAG for the group A and bacBG for the group B virus G protein). The insect cell-produced G proteins migrated more rapidly in SDS-PAGE as compared to HEp-2 cell derived G proteins owing to glycosylation differences. Antigenicity was tested by immunofluorescence; five or five group cross-reactive, five or six group A-specific, and six of six group B-specific MAbs reacted appropriately with bacAG and/or bacBG. In addition, bacAG and bacBG reacted with human polyclonal antibodies to RS virus. Cotton rats were immunized with bacAG, bacBG or a control lysate and challenged intranasally with a group A RS virus. The bacAG-immunized group had a statistically significant reduction in viral replication in the lungs (lung titres as mean log10 p.f.u./g +/- SD, bacAG = 3.1 +/- 1.2; control = 4.8 +/- 0.6, P = 0.013). The bacBG-immunized group showed less reduction in viral titres (bacBG lung titres = 4.1 +/- 0.6, P = 0.13 for bacBG compared to control). Thus, as expected, homologous protein (bacAG) immunization provided more protection against viral replication than immunization with the heterologous protein (bacBG). The G protein of RS virus expressed in insect cells had antigenic and immunogenic features which were similar to that of the G protein expressed in mammalian cells. The baculovirus-expressed G proteins should be useful for the study of immune responses to RS viruses.
authors.affiliation: Department of Pediatrics, University of Alabama at Birmingham 35233, USA.
authors.forename: W M
authors.initials: WM
authors.lastname: Sullender
authors.forename: W J
authors.initials: WJ
authors.lastname: Britt
mesh_terms: D000328:Adult; D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D002460:Cell Line; D004195:Disease Models, Animal; D005455:Fluorescent Antibody Technique; D005822:Genetic Vectors / Q000235:genetics; D015707:HN Protein; D006801:Humans; D009036:Moths / Q000166:cytology; D017924:Nucleopolyhedroviruses / Q000235:genetics; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000276:immunology; D018357:Respiratory Syncytial Virus Infections / Q000276:immunology / Q000517:prevention & control*; D018113:Respiratory Syncytial Virus, Human / Q000235:genetics / Q000276:immunology*; D016205:Sigmodontinae; D018411:Spodoptera / Q000166:cytology; D014614:Vaccines, Synthetic / Q000235:genetics / Q000276:immunology; D014759:Viral Envelope Proteins; D014764:Viral Proteins / Q000235:genetics / Q000276:immunology*; D014765:Viral Vaccines / Q000235:genetics / Q000276:immunology*
chemical_list: D000914:Antibodies, Viral; D015707:HN Protein; D011993:Recombinant Fusion Proteins; D014614:Vaccines, Synthetic; D014759:Viral Envelope Proteins; D014764:Viral Proteins; D014765:Viral Vaccines; C116204:attachment protein G