Stadler E, Dziadek M
Department of Anatomy and Cell Biology, University of Melbourne, Parkville, Victoria, 3052, Australia.
Exp Cell Res. 1996 Dec 15;229(2):360-9. doi: 10.1006/excr.1996.0381.
We have previously shown that isolated mouse fetal choroid plexus epithelial (CPE) cells penetrate a basement membrane matrix (Matrigel) substrate in vitro to form single-layered epithelial vesicles embedded within the matrix. To determine which properties of the matrix are important for inducing or permitting cells to penetrate the substrate and organize into multicellular vesicles we have made quantitative changes to the basement membrane components and growth factors in cell cultures. Matrigel diluted to 33 or 10% with a collagen I gel was not permissive to cell invasion, and CPE cells formed a polarized epithelial monolayer on the substrate surface which had ultrastructural characteristics similar to those of CPE vesicles. Cells in these monolayers proliferated more rapidly than cells in epithelial vesicles. When deliberately embedded within a 33 or 10% Matrigel matrix, CPE cells were able to form vesicles, indicating that a dilute matrix is nonpermissive to cell invasion but promotes epithelial polarization and organization into vesicles. Cells embedded within a 100% collagen I matrix did not proliferate or form epithelial vesicles and the majority of cells did not remain viable. Addition of laminin to the collagen I gel promoted cell adhesion and cell survival, but did not promote the formation of extensive monolayers on the substrate nor the formation of epithelial vesicles within the matrix. Cell invasion into the 33% Matrigel matrix was induced by addition of laminin, nidogen, or a laminin-nidogen complex to the substrate or by addition of TGFbeta2 to the culture medium, but not TGFbeta1 or PDGF. These studies show that CPE cells are sensitive to quantitative changes in matrix composition, which influences their survival and proliferation and also their ability to penetrate the matrix and organize into multicellular epithelial vesicles.
我们之前已经表明，分离的小鼠胎儿脉络丛上皮（CPE）细胞在体外可穿透基底膜基质（基质胶）底物，形成嵌入基质中的单层上皮小泡。为了确定基质的哪些特性对于诱导或允许细胞穿透底物并组织形成多细胞小泡很重要，我们对细胞培养中的基底膜成分和生长因子进行了定量改变。用I型胶原凝胶稀释至33%或10%的基质胶不允许细胞侵袭，CPE细胞在底物表面形成极化的上皮单层，其超微结构特征与CPE小泡相似。这些单层中的细胞比上皮小泡中的细胞增殖更快。当特意嵌入33%或10%的基质胶基质中时，CPE细胞能够形成小泡，这表明稀释的基质不允许细胞侵袭，但促进上皮极化和组织形成小泡。嵌入100% I型胶原基质中的细胞不增殖或形成上皮小泡，并且大多数细胞不能存活。向I型胶原凝胶中添加层粘连蛋白可促进细胞黏附和细胞存活，但不促进在底物上形成广泛的单层，也不促进基质内上皮小泡的形成。向底物中添加层粘连蛋白、巢蛋白或层粘连蛋白-巢蛋白复合物，或向培养基中添加转化生长因子β2（TGFbeta2）可诱导细胞侵入33%的基质胶基质，但转化生长因子β1（TGFbeta1）或血小板衍生生长因子（PDGF）则不能。这些研究表明，CPE细胞对基质组成的定量变化敏感，这会影响它们的存活、增殖以及穿透基质并组织形成多细胞上皮小泡的能力。
