title: Augmentation of cell-mediated responses in vitro by a monoclonal anti-helper factor antibody.
abstract: Previous studies have shown that monoclonal antibody AF3.44.4 has specificity for a constant region determinant on mouse antigen-specific helper factors and that it also binds to cultured T cells with functional helper cell characteristics. The antibody synergizes with antigen to enhance in vitro antibody responses; here we demonstrate that it will also enhance cell-mediated responses in vitro such as in the generation of proliferating cells in mixed lymphocyte responses and in the generation of specific killer cells in cytotoxic T lymphocyte cultures. The mechanism of AF3.44.4-generated enhancement was investigated. Increased levels of the lymphokines IL-2 and BCDF were detected in supernatants of AF3.44.4-treated cultures but the antibody itself could not replace interleukin-2 (IL-2), and would not stimulate primed cells in the absence of antigen. This type of monoclonal antibody which augments immunological responses in an antigen-dependent fashion may provide a new class of immunostimulant and a new approach to augmenting the responses of weak immunogens.
authors.forename: R F
authors.initials: RF
authors.lastname: James
authors.forename: G H
authors.initials: GH
authors.lastname: Sunshine
authors.forename: S
authors.initials: S
authors.lastname: Edwards
authors.forename: D J
authors.initials: DJ
authors.lastname: Maudsley
authors.forename: M
authors.initials: M
authors.lastname: Feldmann
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D000944:Antigens, Differentiation, B-Lymphocyte; D000954:Antigens, Surface / Q000276:immunology; D003602:Cytotoxicity, Immunologic; D007111:Immunity, Cellular; D007376:Interleukin-2 / Q000032:analysis / Q000276:immunology; D007518:Isoantibodies / Q000276:immunology; D007959:Lymphocyte Culture Test, Mixed; D051379:Mice; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*
chemical_list: D000911:Antibodies, Monoclonal; D000944:Antigens, Differentiation, B-Lymphocyte; D000954:Antigens, Surface; D007376:Interleukin-2; D007518:Isoantibodies; C029805:Lyt antibodies