Dunsmore S E, Martinez-Williams C, Goodman R A, Rannels D E
Department of Cellular and Molecular Physiology, Pennsylvania State University College of Medicine, Hershey 17033, USA.
Am J Physiol. 1995 Dec;269(6 Pt 1):L754-65. doi: 10.1152/ajplung.1995.269.6.L754.
Type II pulmonary epithelial cells in primary culture synthesize and deposit an extracellular matrix which has reciprocal biological effects on cellular differentiation. The present work establishes conditions for metabolic labeling of matrix constituents and for separation of cells from the associated matrix; it also defines matrix composition, which does not appear to change qualitatively between days 2 and 6 of primary culture. Type II cells synthesize and deposit a spectrum of radiolabeled components on the culture surface. These include fibronectin, laminin, type IV collagen, and plasminogen activator inhibitor-1, along with additional unidentified proteins. Few radiolabeled proteins in medium conditioned by type II cells bind nonspecifically to the culture surface in the absence of cells. Fibroblasts and macrophages, which may contaminate the primary cultures, do not appear to contribute substantially to the type II cell matrix. These results demonstrate that type II cells synthesize and deposit a complex multicomponent extracellular matrix. The work provides a basis for further investigations of bidirectional interactions between type II cells and the extracellular matrix.
原代培养的II型肺上皮细胞合成并沉积一种细胞外基质，该基质对细胞分化具有相互的生物学作用。目前的工作建立了基质成分代谢标记以及从相关基质中分离细胞的条件；还确定了基质组成，在原代培养的第2天至第6天之间，基质组成在质量上似乎没有变化。II型细胞在培养表面合成并沉积一系列放射性标记成分。这些成分包括纤连蛋白、层粘连蛋白、IV型胶原和纤溶酶原激活物抑制剂-1，以及其他未鉴定的蛋白质。在没有细胞的情况下，由II型细胞条件培养基中的少量放射性标记蛋白质不会非特异性地结合到培养表面。可能污染原代培养物的成纤维细胞和巨噬细胞似乎对II型细胞基质的贡献不大。这些结果表明，II型细胞合成并沉积一种复杂的多组分细胞外基质。这项工作为进一步研究II型细胞与细胞外基质之间的双向相互作用提供了基础。
