title: Antigen-specific suppression of antibody responses by T lymphocytes cytotoxic for antigen-presenting cells.
abstract: In this study we demonstrated an alternative model of the antigen (Ag)-specific suppression of antibody response in mice. Splenocytes that were taken from BALB/c mice immunized by i.v. injection of soluble human serum albumin (HSA) or ovalbumin exhibited MHC-restricted Ag-specific cytotoxicity for the respective antigen-presenting cells (APC). When HSA-primed splenocytes cultured with Ag and interleukin-2 (IL-2) were treated with anti-CD4 or anti-CD8 monoclonal antibody (mAb) plus complement, CD8+ and CD4+ T cells exhibited nearly the same level of cytotoxicity against APC. Furthermore, HSA-primed CD4+ and CD8+ T cells released the same amount of interferon-gamma (IFN-gamma) when stimulated with Ag and IL-2. Recombinant IFN-gamma was shown to suppress the in vitro plaque-forming cell (PFC) response to sheep red blood cells (SRBC) only when it was added within 24 h after addition of Ag. The supernatants from both HSA-primed CD4+ and CD8+ T cells suppressed the PFC response to SRBC in vitro, and the suppressive activity was abrogated by anti-IFN-gamma mAb, but increased by anti-IL 4 mAb. These results suggest that in our system the effector cells for Ag-specific suppression of the antibody response in mice are both the cytotoxic type 1 clones (IFN-gamma-producing) of CD4+ and CD8+ T cells for APC, and that IFN-gamma is a major extracellular effector molecule for such suppression.
authors.affiliation: Department of Microbiology, Yamanashi Medical College, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Kagaya
authors.forename: H
authors.initials: H
authors.lastname: Shang
authors.forename: Y
authors.initials: Y
authors.lastname: Miyakawa
authors.forename: Y
authors.initials: Y
authors.lastname: Fukazawa
mesh_terms: D000818:Animals; D000906:Antibodies / Q000276:immunology / Q000378:metabolism*; D000911:Antibodies, Monoclonal / Q000276:immunology / Q000494:pharmacology; D000938:Antigen-Presenting Cells / Q000166:cytology / Q000276:immunology* / Q000378:metabolism; D015704:CD4 Antigens / Q000032:analysis; D016827:CD8 Antigens / Q000032:analysis; D002478:Cells, Cultured; D017077:Culture Media, Conditioned / Q000494:pharmacology; D000939:Epitopes; D004912:Erythrocytes / Q000502:physiology; D066298:In Vitro Techniques; D007371:Interferon-gamma / Q000378:metabolism / Q000494:pharmacology; D007376:Interleukin-2 / Q000494:pharmacology; D015847:Interleukin-4 / Q000276:immunology; D008285:Major Histocompatibility Complex / Q000276:immunology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008809:Mice, Inbred C3H; D008813:Mice, Inbred ICR; D008819:Mice, Nude; D013154:Spleen / Q000166:cytology / Q000276:immunology; D016176:T-Lymphocyte Subsets / Q000166:cytology / Q000276:immunology / Q000378:metabolism; D013602:T-Lymphocytes, Cytotoxic / Q000166:cytology / Q000276:immunology* / Q000378:metabolism
chemical_list: D000906:Antibodies; D000911:Antibodies, Monoclonal; D015704:CD4 Antigens; D016827:CD8 Antigens; D017077:Culture Media, Conditioned; D000939:Epitopes; D007376:Interleukin-2; D015847:Interleukin-4; D007371:Interferon-gamma