title: Effect of concanavalin A treatment on the allogeneic response of mice to challenge with P 815 mastocytoma: interleukin 2 treatment reverses concanavalin A suppression in vivo.
abstract: Mice injected repeatedly with concanavalin A (Con A) prior to and following challenge with P 815 mastocytoma are suppressed in their cell-mediated cytotoxicity responses. Earlier studies showed that pretreatment of the animals with silica to affect macrophage (M phi) functions reversed the Con A suppression. In the present paper we have shown that peritoneal exudate cells (PEC) induced/activated by ip injection of Con A were able to transfer suppression to normal mice. Separation of the PEC populations into adherent and nonadherent cells abrogated their capacity to transfer suppression. It was further shown that Con A is not functioning in this in vivo system to block effector activity of cytotoxic cells on target cells, and PEC induced with Con A were not directly cytotoxic to target P 815 cells. Finally, we were able to show that the cytotoxicity response of Con A-suppressed mice could be enhanced by treatment with concentrated culture supernatants of normal mouse spleen cells, rich in interleukin 2 (IL 2) activity. Attempts to detect a recently described mouse serum inhibitor of IL 2 in normal or Con A-treated mice were unsuccessful and spleen cells from Con A-treated mice lost their capacity to generate IL 2 in vitro when cultured under appropriate conditions. Taken together, these results suggest that suppression of cell-mediated immune responses in Con A-treated mice results from interruption of the normal generation of IL 2 helper effects necessary for the activation of cytotoxic effector T cells in vivo.
mesh_terms: D000818:Animals; D001202:Ascitic Fluid / Q000276:immunology; D003208:Concanavalin A / Q000008:administration & dosage / Q000494:pharmacology*; D003602:Cytotoxicity, Immunologic; D007116:Immunization, Passive; D007166:Immunosuppressive Agents; D007376:Interleukin-2 / Q000008:administration & dosage* / Q000096:biosynthesis / Q000502:physiology; D008222:Lymphokines / Q000502:physiology; D008262:Macrophage Activation; D008264:Macrophages / Q000276:immunology / Q000637:transplantation; D008297:Male; D012515:Mast-Cell Sarcoma / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D013154:Spleen / Q000276:immunology
chemical_list: D007166:Immunosuppressive Agents; D007376:Interleukin-2; D008222:Lymphokines; D003208:Concanavalin A