Department of Hygiene, Kawasaki Medical School, 577 Matsushima, Kurashiki, Okayama 701-0192, Japan.
Department of Pharmacy and Pharmaceutical Sciences, Fukuyama University, Gakuen-cho 1, Fukuyama, Hiroshima, Hiroshima 729-0292, Japan.
Int J Mol Sci. 2019 May 26;20(10):2581. doi: 10.3390/ijms20102581.
Silicosis is a typical form of pneumoconiosis and is characterized as a type of lung fibrosis. Silica particles are captured and recognized upon by alveolar macrophages via the macrophage receptor with collagenous structure (MARCO) scavenger receptor, and thereafter the inflammasome is activated. Thereafter, various chemokines/cytokines play their roles to eventually form fibrosis. Additionally, silica particles chronically activate T helper cells which sets the background for the formation of silicosis-associated autoimmune disturbances. The occurrence and progression of lung fibrosis, the extracellular matrix-related molecules such as integrins and their ligands including fibronectin, vitronectin, laminin, and collagens, all play important roles. Here, the roles of these molecules in silicosis-related lung fibrosis are reviewed from the literature. Additionally, the measurement of serum nephronectin (Npnt), a new member of the integrin family of ligands, is discussed, together with investigations attempting to delineate the role of Npnt in silica-induced lung fibrosis. Serum Npnt was found to be higher in silicosis patients compared to healthy volunteers and seems to play a role in the progression of fibrosis with other cytokines. Therefore, serum Npnt levels may be employed as a suitable marker to monitor the progression of fibrosis in silicosis patients.
硅肺是一种典型的尘肺病，其特征是一种肺纤维化。硅颗粒通过具有胶原结构的巨噬细胞受体 (MARCO) 清道夫受体被肺泡巨噬细胞捕获和识别，随后激活炎症小体。此后，各种趋化因子/细胞因子发挥作用，最终形成纤维化。此外，硅颗粒慢性激活辅助性 T 细胞，为矽肺相关自身免疫紊乱的形成奠定了基础。肺纤维化的发生和进展、细胞外基质相关分子（如整合素及其配体），包括纤维连接蛋白、纤连蛋白、层粘连蛋白和胶原，都发挥着重要作用。本文从文献中综述了这些分子在矽肺相关肺纤维化中的作用。此外，还讨论了血清肾纳蛋白（Npnt）的测量，Npnt 是整合素家族配体的新成员，以及试图阐明 Npnt 在二氧化硅诱导的肺纤维化中的作用。结果发现，矽肺患者血清 Npnt 水平高于健康志愿者，并且似乎与其他细胞因子一起在纤维化进展中发挥作用。因此，血清 Npnt 水平可作为监测矽肺患者纤维化进展的合适标志物。
