Hirano T, Taga T, Matsuda T, Hibi M, Suematsu S, Tang B, Murakami M, Kishimoto T
Division of Immunology, Osaka University, Japan.
Int J Cell Cloning. 1990 Jan;8 Suppl 1:155-66; discussion 166-7. doi: 10.1002/stem.5530080714.
Interleukin 6 (IL-6) plays critical roles in the immune response and hematopoiesis. It is a potent B cell differentiation factor inducing antibody-forming plasma cells. It enhances interleukin 3-induced proliferation of hematopoietic stem cells. Furthermore, IL-6 induces maturation of megakaryocytes. In IL-6 transgenic mice, a massive polyclonal plasmacytosis and an increase in the number of mature megakaryocytes in the bone marrow were observed. The data indicated that deregulated expression of the IL-6 gene induced a polyclonal plasmacytosis and could be involved in the oncogenesis of plasma cell neoplasias. IL-6 receptor (IL-6R) was molecularly cloned and found to be an immunoglobulin superfamily having an MW of 80 kDa. Upon the binding of IL-6 to its 80 kDa IL-6R, a second non-binding molecule, gp130 was shown to associate with IL-6R. The complex of IL-6 and soluble IL-6R lacking both transmembrane and cytoplasmic domains could bind gp130 and transduce the signal. The results indicate that the IL-6R system consists of two polypeptide chains: one is an 80 kDa ligand-binding molecule and the other is a possible signal transducer, gp130.
白细胞介素6（IL-6）在免疫反应和造血过程中发挥着关键作用。它是一种强大的B细胞分化因子，可诱导形成抗体的浆细胞。它能增强白细胞介素3诱导的造血干细胞增殖。此外，IL-6可诱导巨核细胞成熟。在IL-6转基因小鼠中，观察到大量多克隆浆细胞增多以及骨髓中成熟巨核细胞数量增加。数据表明，IL-6基因表达失调可诱导多克隆浆细胞增多，并可能参与浆细胞肿瘤的肿瘤发生过程。白细胞介素6受体（IL-6R）经分子克隆后发现是一个分子量为80 kDa的免疫球蛋白超家族。当IL-6与其80 kDa的IL-6R结合后，另一个非结合分子gp130会与IL-6R结合。缺乏跨膜和胞质结构域的IL-6与可溶性IL-6R的复合物能够结合gp130并传导信号。结果表明，IL-6R系统由两条多肽链组成：一条是80 kDa的配体结合分子，另一条可能是信号转导分子gp130。
