Gray Darren S, Tien Joe, Chen Christopher S
Department of Biomedical Engineering, Johns Hopkins University School of Medicine, 720 Rutland Avenue, Baltimore, Maryland 21205, USA.
J Biomed Mater Res A. 2003 Sep 1;66(3):605-14. doi: 10.1002/jbm.a.10585.
Adherent cells are strongly influenced by the mechanical aspects of biomaterials, but little is known about the cellular effects of spatial variations in these properties. This work describes a novel method to produce polymeric cell culture surfaces containing micrometer-scale regions of variable stiffness. Substrates made of acrylamide or poly(dimethylsiloxane) were patterned with 100- or 10-microm resolution, respectively. Cells were cultured on fibronectin-coated acrylamide having Young's moduli of 34 kPa and 1.8 kPa, or fibronectin-coated PDMS having moduli of 2.5 MPa and 12 kPa. Over several days, NIH/3T3 cells and bovine pulmonary arterial endothelial cells accumulated preferentially on stiffer regions of substrates. The migration, not proliferation, of cells in response to mechanical patterning (mechanotaxis) was responsible for the accumulation of cells on stiffer regions. Differential remodeling of extracellular matrix protein on stiff versus compliant regions was observed by immunofluorescence staining, and may have been responsible for the observed mechanotaxis. These results suggest that mechanically patterned substrates might provide a general means to study mechanotaxis, and a new approach to patterning cells.
贴壁细胞受到生物材料力学特性的强烈影响，但对于这些特性的空间变化所产生的细胞效应却知之甚少。这项工作描述了一种生产含有微米级可变刚度区域的聚合物细胞培养表面的新方法。分别用分辨率为100微米或10微米的图案化处理由丙烯酰胺或聚二甲基硅氧烷制成的底物。将细胞培养在涂有纤连蛋白、杨氏模量分别为34 kPa和1.8 kPa的丙烯酰胺上，或涂有纤连蛋白、模量分别为2.5 MPa和12 kPa的聚二甲基硅氧烷上。在几天的时间里，NIH/3T3细胞和牛肺动脉内皮细胞优先聚集在底物较硬的区域。细胞对机械图案化（机械趋化）的反应是迁移而非增殖，这导致了细胞在较硬区域的聚集。通过免疫荧光染色观察到细胞外基质蛋白在硬区域和软区域的差异重塑，这可能是观察到的机械趋化的原因。这些结果表明，机械图案化的底物可能提供一种研究机械趋化的通用方法，以及一种对细胞进行图案化的新方法。
