title: Suppression of cell-mediated immunity to challenge with P 815 mastocytoma in concanavalin A-treated mice.
abstract: C57Bl/6 (B6) mice allogeneic to the P 815 mastocytoma tumor cell line when treated with concanavalin A prior to and at frequent intervals following challenge intraperitoneally with 10(7) tumor cells showed a significant suppression of their cell-mediated immune response at 9-10 days when compared with untreated animals. Suppression of the immune response of mice syngeneic (DBA/2) or hybrid (BDF1) to the tumor was also evidenced by increased mortality rates in concanavalin A-treated animals. The suppression of cell-mediated cytotoxicity observed in B6 mice treated with concanavalin A could be reversed by pretreatment with 20 mg silica injected intraperitoneally 7 days prior to challenge. These results suggest that macrophages play a significant role in the concanavalin A-induced immune suppression observed in this in vivo tumor-host system.
mesh_terms: D000818:Animals; D003208:Concanavalin A / Q000494:pharmacology*; D003602:Cytotoxicity, Immunologic / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D007111:Immunity, Cellular / Q000187:drug effects; D008297:Male; D012515:Mast-Cell Sarcoma / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D012822:Silicon Dioxide / Q000494:pharmacology
chemical_list: D003208:Concanavalin A; D012822:Silicon Dioxide