title: Activation of resting human B cells by helper T-cell clone supernatant: characterization of a human B-cell-activating factor.
abstract: The effects of helper T-cell clone supernatants on resting human B cells were investigated. Four different helper T-cell clones (two T4+ and two T8+) were stimulated by anti-T3 monoclonal antibodies on Sepharose beads or anti-T11(2) plus anti-T11(3) monoclonal antibodies. The supernatants from these activated clones induced the proliferation of highly purified resting B lymphocytes from the peripheral blood. The B cells exhibited a cell size and a surface-antigen pattern (4F2 antigen and transferrin receptor) of phase G0 B cells, and they were functionally resting. In response to T-cell supernatants a large fraction of the B cells enlarged and expressed 4F2 antigens and transferrin receptors. In gel filtration, the corresponding activity migrated with an apparent Mr of 12,000-15,000. Our findings strongly support the existence of a human B-cell-activating factor acting on resting B cells and causing them to enter phase G1 of the cell cycle.
mesh_terms: D001402:B-Lymphocytes / Q000166:cytology*; D002999:Clone Cells; D006801:Humans; D007376:Interleukin-2 / Q000502:physiology; D015847:Interleukin-4; D007378:Interleukins / Q000502:physiology*; D008213:Lymphocyte Activation; D008211:Lymphocyte Cooperation; D008222:Lymphokines / Q000502:physiology*; D008970:Molecular Weight; D011971:Receptors, Immunologic / Q000378:metabolism; D015375:Receptors, Interleukin-2; D011990:Receptors, Transferrin / Q000378:metabolism; D006377:T-Lymphocytes, Helper-Inducer / Q000502:physiology*
chemical_list: D007376:Interleukin-2; D007378:Interleukins; D008222:Lymphokines; D011971:Receptors, Immunologic; D015375:Receptors, Interleukin-2; D011990:Receptors, Transferrin; D015847:Interleukin-4