Kaylan Kerim B, Kourouklis Andreas P, Underhill Gregory H
Department of Bioengineering, University of Illinois at Urbana-Champaign.
Department of Bioengineering, University of Illinois at Urbana-Champaign;
J Vis Exp. 2017 Mar 1(121):55362. doi: 10.3791/55362.
Microfabricated cellular microarrays, which consist of contact-printed combinations of biomolecules on an elastic hydrogel surface, provide a tightly controlled, high-throughput engineered system for measuring the impact of arrayed biochemical signals on cell differentiation. Recent efforts using cell microarrays have demonstrated their utility for combinatorial studies in which many microenvironmental factors are presented in parallel. However, these efforts have focused primarily on investigating the effects of biochemical cues on cell responses. Here, we present a cell microarray platform with tunable material properties for evaluating both cell differentiation by immunofluorescence and biomechanical cell-substrate interactions by traction force microscopy. To do so, we have developed two different formats utilizing polyacrylamide hydrogels of varying Young's modulus fabricated on either microscope slides or glass-bottom Petri dishes. We provide best practices and troubleshooting for the fabrication of microarrays on these hydrogel substrates, the subsequent cell culture on microarrays, and the acquisition of data. This platform is well-suited for use in investigations of biological processes for which both biochemical (e.g., extracellular matrix composition) and biophysical (e.g., substrate stiffness) cues may play significant, intersecting roles.
微制造细胞微阵列由弹性水凝胶表面上生物分子的接触印刷组合构成，为测量阵列生化信号对细胞分化的影响提供了一个严格可控的高通量工程系统。最近使用细胞微阵列的研究已证明其在组合研究中的实用性，其中许多微环境因素可并行呈现。然而，这些研究主要集中在调查生化线索对细胞反应的影响。在此，我们展示了一个具有可调材料特性的细胞微阵列平台，用于通过免疫荧光评估细胞分化以及通过牵引力显微镜评估生物力学细胞 - 基质相互作用。为此，我们开发了两种不同的形式，利用在显微镜载玻片或玻璃底培养皿上制备的具有不同杨氏模量的聚丙烯酰胺水凝胶。我们提供了在这些水凝胶基质上制造微阵列、随后在微阵列上进行细胞培养以及获取数据的最佳实践和故障排除方法。该平台非常适合用于研究生物化学（例如细胞外基质组成）和生物物理（例如底物硬度）线索可能发挥重要且相互交叉作用的生物过程。
