Regulation of B lymphocyte responses to IL-4 and IFN-gamma by activation through Ly-6A/E molecules

• Published in: The Journal of immunology (1950) Vol. 144; no. 6; pp. 2197 - 2204
• Main Authors: Codias, EK, Malek, TR
• Format: Journal Article
• Language: English
• Published: Bethesda, MD Am Assoc Immnol 15.03.1990; American Association of Immunologists
• Subjects: Animals; Antibodies, Monoclonal - immunology; Antigens, Ly - immunology; Antigens, Ly - metabolism; B-Lymphocytes - immunology; Biological and medical sciences; Dose-Response Relationship, Drug; Flow Cytometry; Fundamental and applied biological sciences. Psychology; Fundamental immunology; Immunobiology; Immunoglobulin Fab Fragments - immunology; Immunologic Techniques; Interferon-gamma - pharmacology; Interleukin-4 - pharmacology; Lymphocyte Activation; Mice; Mice, Inbred BALB C; Modulation of the immune response (stimulation, suppression); Up-Regulation; Cell proliferation; Rodentia; Cytokine; Cell cell interaction; Activation; B-Lymphocyte; Cell surface; Antigen; Vertebrata; Interleukin 4; Regulation(control); Mammalia; Mouse; T-Lymphocyte; Gamma interferon
• ISSN: 0022-1767; 1550-6606
• DOI: 10.4049/jimmunol.144.6.2197

The Ly-6 family of cell surface molecules has previously been shown to participate in T cell activation. We show that Ly-6A/E proteins also modulated the response of normal B lymphocytes in three separate in vitro assays. First, unfractionated or small resting B cells proliferated when cultured with IFN-gamma, IL-4, and an anti-Ly-6A/E mAb. Second, this anti-Ly-6A/E mAb restored B cell proliferation responses that were inhibited when coculturing the B cells in IFN-gamma, IL-4, and anti-IgM. Third, anti-Ly-6A/E specifically up-regulated the cell surface expression of its own Ag, and this response was dependent upon co-stimulation with IFN-gamma. Mixing of T and B cells in culture suggested that T cells did not contribute substantially to the B cell proliferative response. Moreover, up-regulation of Ly-6A/E was observed for one B cell lymphoma, WEHI-231. Therefore, it appeared that modulation of B cell function by anti-Ly-6A/E was due to a direct effect of the mAb binding to the B cells. Taken together, these data suggest Ly-6A/E proteins are functional on B cells and may play a regulatory role in B cell activation.