Receptors for B cell stimulatory factor 2. Quantitation, specificity, distribution, and regulation of their expression.
B cell stimulatory factor 2 receptors (BSF-2-R) were studied using radioiodinated recombinant BSF-2 with a specific activity of 6.16 X 10(13) cpm/g. Kinetic studies showed that binding of 125I-BSF-2 to CESS cells reached maximum level within 150 min at 0 degrees C. There was a single class of receptors with high affinity (Kd 3.4 X 10(-10) M) on CESS, and the number of receptors was 2,700 per cell. Binding of 125I-BSF-2 to CESS was competitively inhibited by unlabeled BSF-2 but not by IL-1, IL-2, IFN-beta, IFN-gamma, and G-CSF, indicating the presence of the receptors specific for BSF-2. EBV-transformed B lymphoblastoid cell lines (CESS, SKW6-CL4, LCL13, and LCL14) expressed BSF-2-R, whereas Burkitt's lines did not. EBV or EBNA2 did not induce the expression of the receptors on Burkitt's cells. The plasma cell lines (ARH-77 and U266) expressed BSF-2-R, fitting the function of BSF-2 as plasma cell growth factor. Several other cell lines, the histiocytic line U937, the promyelocytic line HL60, the astrocytoma line U373 and the glioblastoma line SK-MG-4, in which BSF-2 was inducible with IL-1 or TPA, displayed BSF-2-R with Kd in the range of 1.3-6.4 X 10(-10) M, suggesting the autocrine mechanism in BSF-2 function. The four T cell lines (CEM, HSB, Jurkat, and OM 1) did not express a detectable number of receptors, but normal resting T cells expressed 100-1,000 receptors per cell. BSF-2-R were not present on normal resting B cells but expressed on activated B cells with a Kd of 3.6-5.0 X 10(-10) M, fitting the function of BSF-2, which acts on B cells at the final maturation stage to induce immunoglobulin production.
Taga
T
T
Division of Immunology, Osaka University, Japan.
Kawanishi
Y
Y
Hardy
R R
RR
Hirano
T
T
Kishimoto
T
T
D001254:Astrocytoma / Q000032:analysis; D001402:B-Lymphocytes / Q000502:physiology*; D001667:Binding, Competitive; D001688:Biological Products / Q000378:metabolism*; D002460:Cell Line; D002472:Cell Transformation, Viral; D016207:Cytokines; D005910:Glioma / Q000032:analysis; D004854:Herpesvirus 4, Human; D018219:Histiocytoma, Benign Fibrous / Q000032:analysis; D006801:Humans; D015850:Interleukin-6; D007457:Iodine Radioisotopes; D007553:Isotope Labeling; D007700:Kinetics; D015470:Leukemia, Myeloid, Acute / Q000378:metabolism; D008222:Lymphokines / Q000378:metabolism*; D019948:Receptors, Interleukin-4; D011975:Receptors, Mitogen / Q000032:analysis* / Q000096:biosynthesis; D011994:Recombinant Proteins / Q000378:metabolism; D014018:Tissue Distribution
D001688:Biological Products; D016207:Cytokines; D015850:Interleukin-6; D007457:Iodine Radioisotopes; D008222:Lymphokines; D019948:Receptors, Interleukin-4; D011975:Receptors, Mitogen; D011994:Recombinant Proteins