Armstrong Margaret T, Armstrong Peter B
Department of Molecular and Cellular Biology, University of California, One Shields Avenue, Davis, CA 95616-8535, USA.
Exp Cell Res. 2003 Aug 15;288(2):235-45. doi: 10.1016/s0014-4827(03)00205-2.
Two cell culture models were utilized to characterize the actions of peptide growth factors on the composition of the extracellular matrix of embryonic mesenchymal tissue. To model the three-dimensional architecture of mesenchymal tissue, chick embryonic mesenchymal cells were maintained in organ culture as adherent cell populations in small three-dimensional tissue spheroids and as sparse populations of cells embedded in a mesh of hydrated native collagen fibrils. Cell proliferation was stimulated by a variety of growth factors. All of the growth factors that elicited a mitogenic response in both of these culture systems also stimulated the deposition of an abundant fibronectin-containing extracellular matrix that colocalized with the regions of active cell proliferation. The suggestion that the matrigenic actions of growth factors for intact mesenchymal tissue are an integral part of mitogenic signaling is supported by the observation that surfaces derivatized with ProNectin, an artificial mimic of the RGD attachment domain of fibronectin, stimulated the proliferation of embryonic mesenchyme in the absence of exogenous growth factors. All of the growth factors that activated proliferation and fibronectin matrix accumulation stimulated the transformation of the mesenchymal cells into myofibroblasts that displayed the marker alpha-smooth muscle actin.
利用两种细胞培养模型来表征肽生长因子对胚胎间充质组织细胞外基质组成的作用。为了模拟间充质组织的三维结构，鸡胚胎间充质细胞在器官培养中作为附着细胞群体维持在小的三维组织球体中，并作为嵌入水合天然胶原纤维网中的稀疏细胞群体。多种生长因子刺激细胞增殖。在这两种培养系统中引发有丝分裂反应的所有生长因子也刺激了富含纤连蛋白的细胞外基质的沉积，该基质与活跃细胞增殖区域共定位。用ProNectin（纤连蛋白RGD附着结构域的人工模拟物）衍生化的表面在没有外源性生长因子的情况下刺激胚胎间充质的增殖，这一观察结果支持了生长因子对完整间充质组织的促基质生成作用是有丝分裂信号传导不可或缺的一部分这一观点。所有激活增殖和纤连蛋白基质积累的生长因子都刺激间充质细胞向显示α-平滑肌肌动蛋白标志物的肌成纤维细胞转化。
