Suppression of lymphocyte signal transduction by murine mastocytoma ascites.
The lymphocyte signal transduction, as determined by intracellular free Ca2+ mobilization of concanavalin A-stimulated T lymphocytes and of anti-immunoglobulin mu chain antibody-stimulated B lymphocytes, was suppressed in spleen cells from mice injected with murine P1.HTR mastocytoma-induced ascites and in spleen cells treated with the ascites in vitro. The suppression was observed both at the peak level and in the reactive pattern of Ca2+ influx. In the suppression, the ascites were replaceable with tumor culture supernatants or tumor homogenates. Correspondingly, primary and secondary cytotoxic T lymphocyte (CTL) responses of DBA/2 mice to allogeneic antigen were also significantly suppressed by injection of the syngeneic P1.HTR tumor-derived ascites. This new finding suggested that the mechanism of the tumorous ascites or of the tumor-derived factor-mediated immunosuppression involves at least in part the suppression of the early event of the signal transduction for lymphocyte activation.
Ding
L
L
Department of Immunology, Nagoya University School of Medicine, Aichi, Japan.
Isobe
K
K
Yoshida
T
T
Nakashima
I
I
D000818:Animals; D001201:Ascites / Q000276:immunology*; D001402:B-Lymphocytes; D002118:Calcium / Q000378:metabolism; D003208:Concanavalin A / Q000494:pharmacology; D007148:Immunoglobulin mu-Chains / Q000276:immunology; D007165:Immunosuppression Therapy; D008213:Lymphocyte Activation / Q000276:immunology; D008214:Lymphocytes / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism; D012515:Mast-Cell Sarcoma / Q000276:immunology*; D051379:Mice; D008815:Mice, Inbred Strains; D009374:Neoplasms, Experimental; D015398:Signal Transduction / Q000502:physiology*; D013491:Suppressor Factors, Immunologic; D013601:T-Lymphocytes
D007148:Immunoglobulin mu-Chains; D013491:Suppressor Factors, Immunologic; D003208:Concanavalin A; D002118:Calcium