Department of Bioengineering & Therapeutic Sciences, University of California, San Francisco, QB3/Byers Hall, Room 203A, MC 2520, 1700 4th Street, San Francisco, CA 94158, USA.
Biomed Microdevices. 2013 Jun;15(3):385-96. doi: 10.1007/s10544-012-9727-7.
Varying geometry and layout of microposts on a cell culture substrate provides an effective technique for applying mechanical stimuli to living cells. In the current study, the optimal geometry and arrangement of microposts on the polydimethylsiloxane (PDMS) surfaces to enhance cell growth behavior were investigated. Human bone marrow derived connective tissue progenitor cells were cultured on PDMS substrates comprising unpatterned smooth surfaces and cylindrical post microtextures that were 10 μm in diameter, 4 heights (5, 10, 20 and 40 μm) and 3 pitches (10, 20, and 40 μm). With the same 10 μm diameter, post heights ranging from 5 to 40 μm resulted in a more than 535 fold range of rigidity from 0.011 nNμm⁻¹ (40 μm height) up to 5.888 nNμm⁻¹(5 μm height). Even though shorter microposts result in higher effective stiffness, decreasing post heights below the optimal value, 5 μm height micropost in this study decreased cell growth behavior. The maximum number of cells was observed on the post microtextures with 20 μm height and 10 μm inter-space, which exhibited a 675 % increase relative to the smooth surfaces. The cells on all heights of post microtextures with 10 μm and 20 μm inter-spaces exhibited highly contoured morphology. Elucidating the cellular response to various external geometry cues enables us to better predict and control cellular behavior. In addition, knowledge of cell response to surface stimuli could lead to the incorporation of specific size post microtextures into surfaces of implants to achieve surface-textured scaffold materials for tissue engineering applications.
微柱几何形状和排布的变化为向活细胞施加机械刺激提供了一种有效技术。在本研究中，研究了 PDMS 表面上微柱的最佳几何形状和排布，以增强细胞的生长行为。将人骨髓来源的结缔组织祖细胞培养在 PDMS 基底上，基底包括无图案的光滑表面和圆柱形微柱结构，微柱的直径为 10μm，高度分别为 5μm、10μm、20μm 和 40μm，节距分别为 10μm、20μm 和 40μm。在相同的 10μm 直径下，微柱高度从 5μm 增加到 40μm，使刚度范围从 0.011 nNμm⁻¹（40μm 高度）增加到 5.888 nNμm⁻¹（5μm 高度），超过 535 倍。尽管较短的微柱会导致更高的有效刚度，但将微柱高度降低到低于最佳值 5μm 会降低细胞的生长行为。在本研究中，20μm 高度和 10μm 间隔的微柱结构上观察到的细胞数量最多，与光滑表面相比，细胞数量增加了 675%。在 10μm 和 20μm 间隔的微柱结构上的所有高度的细胞都呈现出高度变形的形态。阐明细胞对各种外部几何形状的响应，使我们能够更好地预测和控制细胞的行为。此外，对细胞对表面刺激的反应的了解可以导致将特定大小的微柱结构纳入植入物的表面，以实现用于组织工程应用的具有表面纹理的支架材料。
