Taga T, Kawanishi Y, Hardy R R, Hirano T, Kishimoto T
Division of Immunology, Osaka University, Japan.
J Exp Med. 1987 Oct 1;166(4):967-81. doi: 10.1084/jem.166.4.967.
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.
使用比活性为6.16×10¹³ cpm/g的放射性碘化重组B细胞刺激因子2（BSF-2）研究了B细胞刺激因子2受体（BSF-2-R）。动力学研究表明，在0℃下，¹²⁵I-BSF-2与CESS细胞的结合在150分钟内达到最大水平。CESS细胞上存在一类高亲和力（Kd 3.4×10⁻¹⁰ M）的受体，每个细胞的受体数量为2700个。¹²⁵I-BSF-2与CESS细胞的结合受到未标记的BSF-2的竞争性抑制，但不受白细胞介素-1（IL-1）、白细胞介素-2（IL-2）、干扰素-β（IFN-β）、干扰素-γ（IFN-γ）和粒细胞集落刺激因子（G-CSF）的抑制，表明存在BSF-2特异性受体。EB病毒转化的B淋巴母细胞系（CESS、SKW6-CL4、LCL13和LCL14）表达BSF-2-R，而伯基特淋巴瘤细胞系不表达。EB病毒或EBNA2不会诱导伯基特淋巴瘤细胞上受体的表达。浆细胞系（ARH-77和U266）表达BSF-2-R，这符合BSF-2作为浆细胞生长因子的功能。其他几种细胞系，即组织细胞系U937、早幼粒细胞系HL60、星形细胞瘤系U373和成胶质细胞瘤系SK-MG-4，其中BSF-2可被IL-1或佛波酯（TPA）诱导，显示出Kd在1.3 - 6.4×10⁻¹⁰ M范围内的BSF-2-R，提示BSF-2功能中的自分泌机制。四个T细胞系（CEM、HSB、Jurkat和OM 1）未表达可检测数量的受体，但正常静息T细胞每个细胞表达100 - 1000个受体。正常静息B细胞上不存在BSF-2-R，但在活化B细胞上表达，Kd为3.6 - 5.0×10⁻¹⁰ M，这符合BSF-2的功能，即作用于最终成熟阶段的B细胞以诱导免疫球蛋白产生。
