Leivo I, Engvall E, Laurila P, Miettinen M
Department of Pathology, University of Helsinki, Finland.
Lab Invest. 1989 Oct;61(4):426-32.
The expression of merosin and laminin was studied in human schwannomas, plexiform neurofibromas, and malignant schwannomas immunohistochemically using monoclonal antibodies. Merosin is a unique novel tissue-specific basement membrane protein found in basement membranes of trophoblast, striated muscle, and Schwann cells. Merosin is related to laminin, another basement membrane protein with which it shows a homologous C terminal domain. In schwannomas, merosin was only found in areas where tumor cells were in contact with stromal or vascular tissue. Laminin, however, was present in all tumor cell basement membranes. In plexiform neurofibromas large amounts of both merosin and laminin were seen in Schwann cell basement membranes. Very little of either protein was found in malignant schwannomas. Thus merosin is present almost exclusively in highly differentiated Schwann cell neoplasms, and its distribution is more restricted than that of laminin. The expression of merosin in plexiform neurofibromas and in the schwannoma cells juxtaposed to the mesenchymal cells suggests that this protein is induced epigenetically in well-differentiated cells in contact with connective tissue or vascular components.
使用单克隆抗体通过免疫组织化学方法研究了人神经鞘瘤、丛状神经纤维瘤和恶性神经鞘瘤中肌纤连蛋白和层粘连蛋白的表达。肌纤连蛋白是一种独特的新型组织特异性基底膜蛋白，存在于滋养层、横纹肌和雪旺氏细胞的基底膜中。肌纤连蛋白与层粘连蛋白相关，后者是另一种基底膜蛋白，二者具有同源的C末端结构域。在神经鞘瘤中，仅在肿瘤细胞与基质或血管组织接触的区域发现肌纤连蛋白。然而，层粘连蛋白存在于所有肿瘤细胞的基底膜中。在丛状神经纤维瘤中，雪旺氏细胞基底膜中可见大量的肌纤连蛋白和层粘连蛋白。在恶性神经鞘瘤中几乎未发现这两种蛋白中的任何一种。因此，肌纤连蛋白几乎仅存在于高度分化的雪旺氏细胞瘤中，其分布比层粘连蛋白更具局限性。丛状神经纤维瘤以及与间充质细胞并列的神经鞘瘤细胞中肌纤连蛋白的表达表明，这种蛋白是在与结缔组织或血管成分接触的高分化细胞中通过表观遗传诱导产生的。
