Antigen-specific helper T-cell clone supernatant is sufficient to induce both polyclonal proliferation and differentiation of small resting B lymphocytes.
Gradient-purified resting B lymphocytes can be polyclonally stimulated by antigen-specific major histocompatibility complex (MHC)-restricted helper T lymphocytes as well as by antigen-activated helper T-cell supernatant. In contrast to what has been described so far, we show that helper T-cell supernatant (in the absence of any other added stimulus, such as that provided by anti-mu antibodies) is sufficient to induce both proliferation of resting B cells and their differentiation into IgM-secreting cells. The stimulation induced by the helper T-cell supernatant takes place in serum-free medium and is not MHC-restricted. Our findings strongly support the existence of a B-cell activating factor acting on the resting B cell and causing it to enter the G1 phase of the cell cycle in a MHC-unrestricted manner.
D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology*; D002454:Cell Differentiation; D002478:Cells, Cultured; D003470:Culture Media; D008213:Lymphocyte Activation; D008285:Major Histocompatibility Complex; D051379:Mice; D008815:Mice, Inbred Strains; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*
D003470:Culture Media