Abrass C K, Berfield A K
Department of Medicine, Department of Veterans Affairs Medical Center, Seattle, WA, USA.
J Am Soc Nephrol. 1995 Feb;5(8):1591-9. doi: 10.1681/ASN.V581591.
The interaction of cells with their supporting extracellular matrix influences cellular phenotype, cellular proliferation, protein synthetic profile, and specific gene activation. To examine the ability of culture substratum to modulate the phenotype expressed by glomerular epithelial cells (GEC) in culture, GEC were grown on plastic culture plates coated with collagen gels (Type I collagen, Vitrogen) or a complex matrix from the Englebreth-Holm-Swarm tumor (Matrigel). Cultures were examined by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). On untreated plastic, GEC grew in a random pattern. Cells were flat and thin with many filamentous processes. When grown on collagen I gels, GEC grew to confluence as a tight monolayer with typical cobblestone appearance. These cells demonstrated surface microvilli and a central cilium. TEM showed an epithelial appearance with tight junctions. When plated on the surface of Matrigel, GEC formed nests of cells that gradually burrowed into the gel. Proliferation on this matrix was extremely slow. TEM demonstrated that there are surface projections that abut the matrix and that the nests of cells are hollow with a central lumen. SEM demonstrated nests of cells that formed a sphere. Surface microvilli were not as abundant as cells grown on Vitrogen, and cilia were not seen. Cells could be removed from one surface, plated onto another, and would shift phenotype to that observed for subcultures primarily plated onto that surface. Cells on each complex substrate, as well as GEC plated on tissue culture plates coated with individual matrix proteins were biosynthetically labeled with (35S)methionine. The profile and rate of protein synthesis were modified by the plating substrate. These observations demonstrate that rat GEC can be induced to display variable phenotypes in culture that are determined by the plating substrate.(ABSTRACT TRUNCATED AT 250 WORDS)
细胞与其支持性细胞外基质的相互作用会影响细胞表型、细胞增殖、蛋白质合成谱以及特定基因的激活。为了研究培养基质调节培养的肾小球上皮细胞（GEC）所表达表型的能力，将GEC培养在涂有胶原凝胶（I型胶原，Vitrogen）或来自Englebreth-Holm-Swarm肿瘤的复杂基质（基质胶）的塑料培养板上。通过透射电子显微镜（TEM）和扫描电子显微镜（SEM）对培养物进行检查。在未处理的塑料上，GEC呈随机生长模式。细胞扁平且薄，有许多丝状突起。当在I型胶原凝胶上生长时，GEC长成紧密的单层并汇合，呈现典型的鹅卵石外观。这些细胞表现出表面微绒毛和中央纤毛。TEM显示具有紧密连接的上皮外观。当接种在基质胶表面时，GEC形成细胞巢，这些细胞巢逐渐钻入凝胶中。在这种基质上的增殖极其缓慢。TEM显示有与基质相邻的表面突起，并且细胞巢是中空的，有中央管腔。SEM显示形成球体的细胞巢。表面微绒毛不如在Vitrogen上生长的细胞丰富，也未见纤毛。细胞可以从一个表面移除，接种到另一个表面上，并且会将表型转变为主要接种到该表面上的传代培养物所观察到的表型。用（35S）甲硫氨酸对每个复杂底物上的细胞以及接种在涂有单个基质蛋白的组织培养板上的GEC进行生物合成标记。蛋白质合成的谱和速率受接种底物的影响。这些观察结果表明，大鼠GEC在培养中可被诱导表现出由接种底物决定的可变表型。（摘要截短于250字）
