Separation of events mediating B cell proliferation and Ig production by using T cell membranes and lymphokines

• Published in: The Journal of immunology (1950) Vol. 145; no. 7; pp. 2025 - 2034
• Main Authors: Hodgkin, PD, Yamashita, LC, Coffman, RL, Kehry, MR
• Format: Journal Article
• Language: English
• Published: Bethesda, MD Am Assoc Immnol 01.10.1990; American Association of Immunologists
• Subjects: Analysis of the immune response. Humoral and cellular immunity; Animals; Antibody Formation; Antigens, Differentiation, T-Lymphocyte - physiology; B-Lymphocytes - immunology; Biological and medical sciences; CD3 Complex; Cell Communication; Cell Cycle; Cell Membrane - physiology; Concanavalin A - pharmacology; Fundamental and applied biological sciences. Psychology; Fundamental immunology; Immunobiology; In Vitro Techniques; Interleukin-4 - pharmacology; Lymphocyte Activation; Lymphokines - physiology; Mice; Mice, Inbred Strains; Organs and cells involved in the immune response; Receptors, Antigen, T-Cell - physiology; T-Lymphocytes, Helper-Inducer - immunology; Cell proliferation; Immunoglobulins; Rodentia; Helper cell; Activation; B-Lymphocyte; Lymphokine; Vertebrata; Mammalia; Mouse; T-Lymphocyte; Plasma membrane; Production
• ISSN: 0022-1767; 1550-6606
• DOI: 10.4049/jimmunol.145.7.2025

The initiation by Th cells of B cell proliferation and differentiation to produce Ig involves both cell contact- and lymphokine-mediated signals. Plasma membrane-enriched fractions from stimulated, but not unstimulated, Th cells induced Ag nonspecific and MHC unrestricted proliferation of 60 to 70% of small dense B cells. Induction of stimulatory membrane activity was inhibited by cycloheximide, and the activity was eliminated by both protease and heat treatment of membranes. Membrane-stimulated B cells did not differentiate to secrete Ig; however, addition of a lymphokine-containing supernatant from activated Th cells or the combination of IL-4 and IL-5 resulted in substantial Ig production, predominantly of the IgM, IgG1, IgA, and IgE isotypes. The quantity and isotype distribution of the antibodies secreted were similar to those produced after B cell activation by the intact Th cells and Ag. Therefore, membranes from activated Th cells in combination with lymphokines normally secreted by such cells can replace intact Th cells and provide a defined system to identify molecular events important for B cell activation.