Department of Biomedical Engineering, University of California, Davis, 451 Health Sciences Drive, Davis, CA, 95616, USA.
Department of Orthopaedic Surgery, UC Davis Health, Sacramento, CA, 95817, USA.
J Mol Med (Berl). 2020 Mar;98(3):425-435. doi: 10.1007/s00109-020-01883-1. Epub 2020 Feb 4.
Cell-based therapeutic approaches are an exciting strategy to replenish compromised endothelial cell (EC) populations that contribute to impaired vasculogenesis. Co-cultures of ECs and mesenchymal stromal cells (MSCs) can enhance neovascularization over ECs alone, but the efficacy of cells is limited by rapid cell death upon implantation. Co-culture spheroids exhibit improved survival compared with monodisperse cells, yet little is known about the influence of spatial regulation of ECs within co-culture spheroids. We hypothesized that EC sprouting from co-culture spheroids is a function of EC spatial localization. We formed co-culture spheroids containing ECs and MSCs in two formats: ECs uniformly distributed throughout the spheroid (i.e., mixed) or seeded on the perimeter of the MSC core (i.e., shell). Qualitative observations suggested increased vasculogenesis for mixed co-culture spheroids compared with shell conformations as early as day 3, yet quantitative metrics did not reveal significant differences in network formation between these 3D structures. Notch3 expression demonstrated significant increases in cell-cell communication in mixed conformations compared with shell counterparts. Furthermore, knockdown of Notch3 in MSCs abrogated the vasculogenic potential of mixed spheroids, supporting its role in promoting EC-MSC contacts. This study highlights the direct impact of EC-MSC contacts on sprouting and provides insight to improve the quality of network formation. KEY MESSAGES: • Endothelial cell (EC) localization can be controlled in co-culture EC-MSC spheroids. • Mixed spheroids exhibit consistent networks compared to shell counterparts. • Differences in NOTCH3 were observed between mixed and shell spheroids. • NOTCH3 may be a necessary target for improved vasculogenic potential.
基于细胞的治疗方法是一种很有前途的策略，可以补充受损的内皮细胞（EC）群体，从而促进受损的血管生成。EC 和间充质基质细胞（MSCs）的共培养可以增强 EC 单独培养时的新生血管生成能力，但细胞的功效受到植入后快速细胞死亡的限制。共培养球体与单分散细胞相比表现出更好的存活率，但对于 EC 在共培养球体中的空间调节对其的影响知之甚少。我们假设 EC 从共培养球体中的发芽是 EC 空间定位的一个功能。我们以两种形式形成含有 EC 和 MSCs 的共培养球体：EC 均匀分布在球体中（即混合）或接种在 MSC 核心的周边（即壳）。定性观察表明，混合共培养球体的血管生成能力比壳构象早到第 3 天就有所增加，但定量指标并未显示这些 3D 结构之间的网络形成有显著差异。与壳对应物相比，混合构象中 Notch3 的表达显示出细胞间通讯的显著增加。此外，MSCs 中的 Notch3 敲低消除了混合球体的血管生成潜力，支持其在促进 EC-MSC 接触中的作用。本研究强调了 EC-MSC 接触对发芽的直接影响，并为提高网络形成质量提供了深入了解。主要信息： • 可以控制共培养 EC-MSC 球体中 EC 的定位。 • 与壳对应物相比，混合球体表现出一致的网络。 • 在混合和壳球体之间观察到 NOTCH3 的差异。 • NOTCH3 可能是改善血管生成潜力的必要靶点。
