title: Immunization of BALB/c mice with recombinant simian virus 40 large tumor antigen induces antibody-dependent cell-mediated cytotoxicity against simian virus 40-transformed cells. An antibody-based mechanism for tumor immunity.
abstract: In this report, we describe an immune mechanism that seems to play a role in tumor immunity in BALB/c mice challenged with SV40-transformed cells. This immune mechanism was induced by immunization of mice with rSV40 large tumor Ag (T-Ag). After rSV40 T-Ag immunization, BALB/c mice were protected from a lethal tumor challenge with syngeneic SV40-transformed cells (mKSA). Specifically, we examined CTL activity, NK activity, complement-dependent cytotoxicity, and Ab-dependent cell-mediated cytotoxicity (ADCC) in rSV40 T-Ag-immunized mice that were protected from a subsequent lethal tumor challenge. Immune splenocytes from surviving animals that were subsequently primed in vitro with rSV40 T-Ag demonstrated little to no SV40 T-Ag-specific CTL activity. In addition, natural immunity, as assessed by NK lytic activity, was comparable to that of unimmunized animals. Similarly, minimal significant complement-dependent cytotoxicity of radiolabeled mKSA cells was demonstrated by SV40 T-Ag-specific serum Abs. However, SV40 T-Ag-specific Abs using peritoneal exudate cells as effectors, exhibited significant levels of ADCC against radiolabeled mKSA target cells. Together, these studies indicate that rSV40 T-Ag immunization elicited ADCC that may represent a potential humoral immune mechanism involved in the protection of BALB/c mice from a lethal challenge with syngeneic SV40-transformed cells.
authors.affiliation: Department of Virology and Immunology, Southwest Foundation for Biomedical Research, San Antonio, Texas 78228.
authors.forename: R K
authors.initials: RK
authors.lastname: Bright
authors.forename: M H
authors.initials: MH
authors.lastname: Shearer
authors.forename: R C
authors.initials: RC
authors.lastname: Kennedy
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000276:immunology; D000920:Antibody-Dependent Cell Cytotoxicity; D015703:Antigens, CD / Q000032:analysis; D000952:Antigens, Polyomavirus Transforming / Q000276:immunology*; D002472:Cell Transformation, Viral / Q000276:immunology; D004306:Dose-Response Relationship, Immunologic; D005260:Female; D007111:Immunity, Cellular; D007132:Immunoglobulin Isotypes / Q000276:immunology; D007694:Killer Cells, Natural / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D009374:Neoplasms, Experimental / Q000276:immunology; D013539:Simian virus 40 / Q000276:immunology*; D014614:Vaccines, Synthetic
chemical_list: D000914:Antibodies, Viral; D015703:Antigens, CD; D000952:Antigens, Polyomavirus Transforming; D007132:Immunoglobulin Isotypes; D014614:Vaccines, Synthetic