Suppression of the in vitro secondary antibody response of rabbit lymphoid cells by Concanavalin A.
The effect of various concentrations of concanavalin A (Con A) on the in vitro secondary antibody response of rabbit lymph node and spleen cells to sheep red blood cells (SRBC) was studied. Complete suppression of the IgM plaque-forming cell (PFC) response of both lymph node and spleen cultures was observed when 10 mug/ml of Con A was added at the time of initiation of the cultures whereas only partial suppression was observed when 1 mug/ml of Con A was added. Moreover, marked suppression of the immune responses of both spleen and lymph node cultures was observed when 10 mug/ml of Con A was added at 24 hr after antigenic challenge and to a lesser extent when added at 48 hr. Suppression of the IgM PFC response was also detected when spleen cultures were exposed to 10 mug/ml of Con A for as little as 2 hr after antigenic challenge. However, substantial increases in DNA synthesis were observed only in those cultures which were in contact with Con A for at least 24 hr. Finally evidence is presented that the Con A-induced suppression is mediated by a soluble substance(s).
D000818:Animals; D000917:Antibody Formation / Q000187:drug effects*; D000941:Antigens; D002478:Cells, Cultured; D003208:Concanavalin A / Q000494:pharmacology*; D004912:Erythrocytes / Q000276:immunology; D008198:Lymph Nodes / Q000166:cytology / Q000276:immunology*; D008362:Mannosides / Q000494:pharmacology; D011817:Rabbits; D012756:Sheep / Q000097:blood; D013154:Spleen / Q000166:cytology / Q000276:immunology*; D013936:Thymidine / Q000378:metabolism; D013997:Time Factors; D014316:Tritium; D010948:Viral Plaque Assay
D000941:Antigens; D008362:Mannosides; D014316:Tritium; D003208:Concanavalin A; D013936:Thymidine