Formation of capillary blood vasculature is a critical requirement for native as well as engineered organs and can be induced in vitro by coculturing endothelial cells with fibroblasts. However, whether these fibroblasts are required only in the initial morphogenesis of endothelial cells or needed throughout is unknown, and the ability to remove these stromal cells after assembly can be useful for clinical translation. In this study, a technique termed CAMEO (Controlled Apoptosis in Multicellular Tissues for Engineered Organogenesis) is introduced, whereby fibroblasts are selectively ablated on demand, and it is utilized to probe the dispensability of fibroblasts in vascular morphogenesis. The presence of fibroblasts is shown to be necessary only during the first few days of endothelial cell morphogenesis, after which they can be ablated without significantly affecting the structural and functional features of the developed vasculature. Furthermore, the use of CAMEO to vascularize a construct containing primary human hepatocytes that improved tissue function is demonstrated. In conclusion, this study suggests that transient, initial support from fibroblasts is sufficient to drive vascular morphogenesis in engineered tissues, and this strategy of engineering‐via‐elimination may provide a new general approach for achieving desired functions and cell compositions in engineered organs.

中文翻译：

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成纤维细胞的瞬时支持足以驱动工程组织中的功能性血管化

毛细血管系统的形成是天然和工程器官的关键要求，可以通过将内皮细胞与成纤维细胞共培养在体外诱导。然而，这些成纤维细胞是仅在内皮细胞的初始形态发生中需要还是在整个过程中需要尚不清楚，组装后去除这些基质细胞的能力可用于临床转化。在这项研究中，引入了一种称为 CAMEO（用于工程器官发生的多细胞组织中的受控细胞凋亡）的技术，其中成纤维细胞按需选择性消融，并用于探测成纤维细胞在血管形态发生中的可有可无。仅在内皮细胞形态发生的前几天才需要成纤维细胞的存在，之后它们可以被消融，而不会显着影响发达脉管系统的结构和功能特征。此外，证明了使用 CAMEO 使含有原代人肝细胞的构建体血管化，从而改善组织功能。总之，这项研究表明，来自成纤维细胞的短暂的初始支持足以驱动工程组织中的血管形态发生，而这种通过工程消除的策略可能为在工程器官中实现所需功能和细胞组成提供一种新的通用方法。