title: Receptors for B-cell stimulatory factor-1 expressed on cells of haematopoietic lineage.
abstract: B-cell stimulatory factor-1 (BSF-1) is a T-cell product of relative molecular mass 20,000 (Mr, 20K) initially described as a cofactor required for DNA synthesis by resting mouse B cells stimulated with low concentrations of anti-IgM antibodies. It acts on resting B cells to enhance the expression of class II major histocompatibility complex (MHC) molecules, to prepare these cells to respond more promptly to subsequent stimuli, such as anti-IgM antibodies, and causes the secretion of IgG1 and IgE by B cells stimulated with lipopolysaccharide (LPS). BSF-1 has been shown to stimulate T cell lines, resting T cells and some mast cell lines. Recently, the designation interleukin-4 (IL-4) has been suggested for BSF-1. We report here the existence of high-affinity cell-surface receptors specific for BSF-1 on both B and T lymphocytes, and on cells of several other haematopoietic lineages, including mast cell, macrophage and undifferentiated haematopoietic cell lines. Resting B and T lymphocytes express receptors, which increase in number upon activation of B cells with LPS or anti-IgM, and of T cells with concanavalin A. Cross-linking of 125I-labelled-BSF-1 to its receptors creates a complex of Mr approximately 80,000.
mesh_terms: D000818:Animals; D001402:B-Lymphocytes / Q000032:analysis; D002460:Cell Line; D006133:Growth Substances / Q000378:metabolism*; D006801:Humans; D015847:Interleukin-4; D007962:Leukocytes / Q000032:analysis*; D008222:Lymphokines / Q000378:metabolism*; D008264:Macrophages / Q000032:analysis; D008407:Mast Cells / Q000032:analysis; D051379:Mice; D008811:Mice, Inbred DBA; D011971:Receptors, Immunologic / Q000032:analysis; D015375:Receptors, Interleukin-2; D019948:Receptors, Interleukin-4; D011975:Receptors, Mitogen / Q000032:analysis*; D013154:Spleen / Q000032:analysis; D013601:T-Lymphocytes / Q000032:analysis
chemical_list: D006133:Growth Substances; D008222:Lymphokines; D011971:Receptors, Immunologic; D015375:Receptors, Interleukin-2; D019948:Receptors, Interleukin-4; D011975:Receptors, Mitogen; D015847:Interleukin-4