title: In vivo resistance and in vitro cellular reactivity against lymphosarcoma cells in immunized mice.
abstract: In an earlier report we have shown that an allogeneic but not a syngeneic immunization of mice with lymphoma cells evoked a humoral complement-dependent cytotoxic response against lymphoma cells syngeneic with the serum. Here we report the results of an investigation, using the same experimental model, on the cellular antitumor response in vitro and the in vivo tumor resistance. Both the allogeneic and the syngeneic antitumor immunizations induced a cellular immune response that was detectable in vitro and that not inhibited by the correspondent antiserum that was obtained with the same type of immunization. The humoral and cellular immune responses evoked in our system seem, therefore, directed against different antigenic determinants. In the in vivo experiments the maximal antitumor protection was obtained in mice immunized syngeneically, whereas the allogeneic immunization gave a protection that was similar to that obtained in mice immunized with normal allogeneic thymus cells. However, mitomycin-C-blocked thymus cells were unable to induce any protection against the tumor challenge, whereas blocked allogeneic tumor cells conferred the same degree of protection as that obtained with untreated cells. The in vivo transfer in untreated mice of sera obtained with syngeneic or allogeneic antitumor immunization did not give any protection against the tumor challenge.
mesh_terms: D000818:Animals; D000917:Antibody Formation; D000951:Antigens, Neoplasm; D003602:Cytotoxicity, Immunologic; D005260:Female; D007111:Immunity, Cellular; D007114:Immunization; D066298:In Vitro Techniques; D007694:Killer Cells, Natural / Q000276:immunology; D008228:Lymphoma, Non-Hodgkin / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D013045:Species Specificity; D013950:Thymus Gland / Q000637:transplantation
chemical_list: D000951:Antigens, Neoplasm