Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA.
Biomacromolecules. 2012 Sep 10;13(9):2917-25. doi: 10.1021/bm300949k. Epub 2012 Aug 27.
To understand complex micro/nanoscale ECM stem cell interactions, reproducible in vitro models are needed that can strictly recapitulate the relative content and spatial arrangement of native tissue. Additionally, whole ECM proteins are required to most accurately reflect native binding dynamics. To address this need, we use multiphoton excited photochemistry to create 3D whole protein constructs or "modules" to study how the ECM governs stem cell migration. The constructs were created from mixtures of BSA/laminin (LN) and BSA alone, whose comparison afforded studying how the migration dynamics are governed from the combination of morphological and ECM cues. We found that mesenchymal stem cells interacted for significantly longer durations with the BSA/LN constructs than pure BSA, pointing to the importance of binding cues of the LN. Critical to this work was the development of an automated system with feedback based on fluorescence imaging to provide quality control when synthesizing multiple identical constructs.
为了理解复杂的微/纳米尺度细胞外基质-干细胞相互作用，需要能够严格重现天然组织中相对含量和空间排列的可重复的体外模型。此外，还需要完整的细胞外基质蛋白以最准确地反映天然结合动力学。为了满足这一需求，我们使用多光子激发光化学来创建 3D 全蛋白构建体或“模块”，以研究细胞外基质如何控制干细胞迁移。这些构建体是由 BSA/层粘连蛋白（LN）和单独的 BSA 混合物制成的，通过比较可以研究细胞迁移动力学如何受到形态和细胞外基质线索的组合的控制。我们发现间充质干细胞与 BSA/LN 构建体的相互作用时间明显长于纯 BSA，这表明 LN 的结合线索很重要。这项工作的关键是开发了一种具有基于荧光成像的反馈的自动化系统，以在合成多个相同的构建体时提供质量控制。
