Meakins Christie Laboratories, McGill University, Montreal, Quebec, Canada.
Matrix Biol. 2012 Mar;31(2):101-12. doi: 10.1016/j.matbio.2011.11.001. Epub 2011 Dec 2.
Growth on a decorin matrix results in decreased human airway smooth muscle cell (HASMC) number, by decreasing proliferation and increasing apoptosis. We questioned whether these effects were related to abnormal extracellular matrix (ECM)-cell adhesion. HASMCs were seeded on decorin, biglycan, collagen type I or plastic. Actin organization and focal adhesion formation were assessed by staining for filamentous (F) and globular (G) actin, and vinculin, respectively. Gene expression for focal adhesion proteins, ECM molecules and HASMC receptors was measured. Protein levels for fibronectin, α(2), α(5), α(v) and β(3) integrin subunits and, focal adhesion kinase (FAK) were assessed. F-actin filaments were prominent in cells seeded on collagen I and plastic, less apparent in cells cultured on biglycan and faint in cells on decorin. Vinculin clustering was decreased in cells seeded on decorin and biglycan, as was vinculin gene expression. Compared to cells on plastic, cells on decorin had an increase in fibronectin gene expression. Seeding on decorin caused an increase in α(2) integrin subunit and platelet-derived growth factor receptor A gene expression. There was also an increase in α(2) and α(v) integrin subunit protein. Finally, FAK protein levels in cells seeded on decorin or biglycan were decreased compared to cells seeded on plastic or collagen I. Cells grown on proteoglycan matrices demonstrate evidence of abnormalities during many of the key processes involved in normal cell adhesion. Upregulation of cell surface receptor proteins, such as α(2) integrin subunit, may represent a compensatory mechanism to overcome poor adhesion induced by growth on these matrices.
在聚集蛋白聚糖基质上生长会导致人呼吸道平滑肌细胞（HASMC）数量减少，这是通过降低增殖和增加凋亡来实现的。我们质疑这些影响是否与细胞外基质（ECM）-细胞黏附异常有关。将 HASMC 接种到聚集蛋白聚糖、核心蛋白聚糖、I 型胶原蛋白或塑料上。通过分别对丝状（F）和球状（G）肌动蛋白以及 vinculin 进行染色来评估肌动蛋白组织和黏着斑的形成。测量黏着斑蛋白、ECM 分子和 HASMC 受体的基因表达。评估纤维连接蛋白、α(2)、α(5)、α(v)和β(3)整合素亚基和黏着斑激酶（FAK）的蛋白水平。在接种于 I 型胶原蛋白和塑料的细胞中，F-肌动蛋白丝很明显，在接种于核心蛋白聚糖的细胞中则不明显，而在接种于聚集蛋白聚糖的细胞中则很淡。在接种于聚集蛋白聚糖和核心蛋白聚糖的细胞中，vinculin 聚集减少，vinculin 基因表达减少。与接种于塑料的细胞相比，接种于聚集蛋白聚糖的细胞中纤维连接蛋白基因表达增加。在接种于聚集蛋白聚糖的情况下，α(2)整合素亚基和血小板衍生生长因子受体 A 基因表达增加。α(2)和α(v)整合素亚基蛋白也增加。最后，与接种于塑料或 I 型胶原蛋白的细胞相比，接种于聚集蛋白聚糖或核心蛋白聚糖的细胞中的 FAK 蛋白水平降低。在蛋白聚糖基质上生长的细胞在许多正常细胞黏附涉及的关键过程中表现出异常。细胞表面受体蛋白（如α(2)整合素亚基）的上调可能代表一种补偿机制，以克服在这些基质上生长所诱导的不良黏附。
