Involvement of antigen-presenting cells in the enhancement of the in vitro antibody responses by cholera toxin B subunit.
The enhancing effect of cholera toxin B subunit (CTB) on primary antibody responses to keyhole limpet haemocyanin (KLH) and the cellular basis of the effect were investigated, using in vitro cultures of mouse spleen cells. CTB (1-100 ng/ml) enhanced anti-KLH IgM, IgG and IgA antibody responses in a dose-dependent manner, when added to the cultures with KLH. This immunoenhancement was antigen specific, but not due to either polyclonal activation of the spleen cells or antigenic cross-reactivity between CTB and KLH. CTB did not affect the kinetics of the anti-KLH antibody responses. Early (Days 0-1) addition of CTB to the cultures enhanced the anti-KLH antibody production, whereas late (Days 5-7) addition of CTB did not. Addition of CTB with KLH to splenic adherent cells (SAC) resulted in a dose-dependent enhancement of the anti-KLH antibody responses, when the SAC were reconstituted with unimmunized non-adherent cells. Moreover, CTB enhanced IL-1 secretion from SAC incubated with KLH. These results suggest that CTB enhances the primary anti-KLH antibody responses in vitro by acting on early events in the responses, and that antigen-presenting cells play a major role in the enhancement.
Hirabayashi
Y
Y
Department of Pathology, National Institute of Health, Tokyo, Japan.
Tamura
S I
SI
Shimada
K
K
Kurata
T
T
D000276:Adjuvants, Immunologic; D000818:Animals; D000938:Antigen-Presenting Cells / Q000276:immunology*; D000941:Antigens / Q000276:immunology; D002478:Cells, Cultured; D002772:Cholera Toxin / Q000276:immunology*; D004306:Dose-Response Relationship, Immunologic; D000939:Epitopes / Q000276:immunology; D005260:Female; D006433:Hemocyanins / Q000276:immunology; D007375:Interleukin-1 / Q000096:biosynthesis; D007700:Kinetics; D051379:Mice; D008810:Mice, Inbred C57BL; D010446:Peptide Fragments / Q000276:immunology*; D013154:Spleen / Q000276:immunology
D000276:Adjuvants, Immunologic; D000941:Antigens; D000939:Epitopes; D007375:Interleukin-1; D010446:Peptide Fragments; C050310:cholera toxin, B subunit (50-64); D002772:Cholera Toxin; D006433:Hemocyanins; C032808:keyhole-limpet hemocyanin