Tzeng S F, Deibler G E, DeVries G H
Research Service, Hines/VA Hospital, Illinois 60141, USA.
Neurochem Res. 1999 Feb;24(2):255-60. doi: 10.1023/a:1022514105129.
Myelin basic protein (MBP) and two peptides derived from MBP (MBP(1-44) and MBP(152-167)) stimulated Schwann cell (SC) proliferation in a cAMP-mediated process. The two mitogenic regions of MBP did not compete with one another for binding to SC suggesting a distinctive SC receptor for each mitogenic peptide. Neutralizing antibodies to the fibroblast growth factor receptor blocked the mitogenic effect of the myelin-related SC mitogen found in the supernatant of myelin-fed macrophages. The binding of 125I-MBP to Schwann cells was specifically inhibited by basic fibroblast growth factor (bFGF) and conversely the binding of 125I-bFGF was competitively inhibited by MBP. These data suggested that the mitogenic effect of one MBP peptide was mediated by a bFGF receptor. The binding of MBP to ganglioside GM1 and the ability of MBP peptides containing homology to the B subunit of cholera toxin (which binds ganglioside GM1) to compete for the binding of a mitogenic peptide (MBP(1-44)) to SC, identified ganglioside GM1 as a second SC receptor. Based on these results, we conclude that MBP(1-44) and MBP(152-167) associate with ganglioside GM1 and the bFGF receptor respectively to stimulate SC mitosis.
髓鞘碱性蛋白（MBP）及其衍生的两种肽（MBP(1 - 44)和MBP(152 - 167)）通过环磷酸腺苷（cAMP）介导的过程刺激雪旺细胞（SC）增殖。MBP的两个促有丝分裂区域在与雪旺细胞结合时互不竞争，这表明每种促有丝分裂肽都有独特的雪旺细胞受体。针对成纤维细胞生长因子受体的中和抗体可阻断在喂食髓磷脂的巨噬细胞上清液中发现的髓磷脂相关雪旺细胞有丝分裂原的促有丝分裂作用。碱性成纤维细胞生长因子（bFGF）可特异性抑制125I - MBP与雪旺细胞的结合，反之，MBP可竞争性抑制125I - bFGF的结合。这些数据表明，一种MBP肽的促有丝分裂作用是由bFGF受体介导的。MBP与神经节苷脂GM1的结合，以及与霍乱毒素B亚基（可结合神经节苷脂GM1）具有同源性的MBP肽竞争促有丝分裂肽（MBP(1 - 44)）与雪旺细胞结合的能力，确定神经节苷脂GM1为雪旺细胞的第二种受体。基于这些结果，我们得出结论，MBP(1 - 44)和MBP(152 - 167)分别与神经节苷脂GM1和成纤维细胞生长因子受体结合，以刺激雪旺细胞有丝分裂。
