T-cell immunity to murine Moloney sarcoma virus-induced tumours: L3T4+ T cells are necessary for resistance to primary sarcoma growth, but Lyt-2+ T cells are required for resistance to secondary tumour cell challenge.
Experimental protocols have been devised to deliniate the importance of T-cell subsets in immunity to Moloney sarcoma virus-induced tumours using the surface antigens L3T4 and Lyt-2 as markers of helper and cytotoxic cells, respectively. Because the monoclonal antibodies used have been shown to deplete T-cell subsets in vivo, we have been able to study the role of L3T4+ and Lyt-2+ T cells in the primary response to MSV for the first time. The results clearly show that L3T4+ T cells are the most important in resistance to the viral challenge. Mice injected with monoclonal antibodies to L3T4 grew large tumours following injection of a viral innoculum that was resisted by untreated mice or mice injected with monoclonal antibodies to Lyt-2. The same monoclonal antibodies were used to remove primed L3T4+ or Lyt-2+ T cells in vitro in adoptive transfer experiments. Normal unirradiated mice were protected from a challenge of WR19L lymphoma cells when they were given primed spleen and lymph node cells intraperitoneally. Depletion of Lyt-2+ T cells before adoptive transfer abolished this protective effect. Depletion of L3T4+ cells had no effect on the ability of primed cells to transfer immunity. Thus, while L3T4+ T cells are required for the primary rejection of MSV, only primed Lyt-2+ T cells are able to transfer resistance to a secondary challenge of lymphoma cells.
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D007111:Immunity, Cellular; D007116:Immunization, Passive; D007156:Immunologic Memory; D051379:Mice; D008807:Mice, Inbred BALB C; D008980:Moloney murine sarcoma virus; D012513:Sarcoma, Experimental / Q000276:immunology* / Q000517:prevention & control; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*
D000911:Antibodies, Monoclonal