Nanopatterning of fibronectin and the influence of integrin clustering on endothelial cell spreading and proliferation.
Nanopatterning of fibronectin and the influence of integrin clustering on endothelial cell spreading and proliferation.
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DOI：
10.1002/jbm.a.31725
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发表时间：
2008-10
期刊：
影响因子：
--
通讯作者：
J. H. Slater;W. Frey
中科院分区：
文献类型：
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作者：
J. H. Slater;W. Frey
从最初的结合事件到形成小的焦点复合体，研究细胞与细胞外基质黏附的成熟阶段一直是具有挑战性的，因为制备具有可控生化功能的必要的纳米颗粒底物是困难的。我们介绍了具有可控大小和间距的纤维连接蛋白纳米管的表面的制备和表征，这些纳米管在非粘附性聚乙二醇背景下提供了明确的细胞粘附点。纳米表面使我们能够控制每个粘附点内的纤维连接蛋白蛋白的数量，从9个到250个，从而限制每个细胞-基质粘附点涉及的整合素的数量。我们证明在纳米岛上存在纤维连接蛋白，而在钝化的背景上没有观察到蛋白质。我们发现，与玻璃对照组相比，细胞与纳米管的粘附性要小得多，分布也更均匀。纳米图形只在较长时间内影响细胞的增殖，但在早期和后期都影响扩散，表明黏附大小和黏附密度在控制细胞黏附和信号转导中起作用。然而，所有图案上的纤维连接蛋白的总密度远远低于均匀涂覆的对照表面，这表明黏附配体的局部密度而不是平均密度是细胞增殖和扩散的重要参数。
Investigating stages of maturation of cellular adhesions to the extracellular matrix from the initial binding events to the formation of small focal complexes has been challenging because of the difficulty in fabricating the necessary nanopatterned substrates with controlled biochemical functionality. We present the fabrication and characterization of surfaces presenting fibronectin nanopatterns of controlled size and pitch that provide well-defined cellular adhesion sites against a nonadhesive polyethylene glycol background. The nanopatterned surfaces allow us to control the number of fibronectin proteins within each adhesion site from 9 to 250, thereby limiting the number of integrins involved in each cell-substrate adhesion. We demonstrate the presence of fibronectin on the nanoislands, while no protein was observed on the passivated background. We show that the cell adheres to the nanopatterns with adhesions that are much smaller and more evenly distributed than on a glass control. The nanopattern influences cellular proliferation only at longer times, but influences spreading at both early and later times, indicating adhesion size and adhesion density play a role in controlling cell adhesion and signaling. However, the overall density of fibronectin on all patterns is far lower than on homogeneously coated control surfaces, showing that the local density of adhesion ligands, not the average density, is the important parameter for cell proliferation and spreading.