EAGER: High-Throughput Bioprinting of Vascularized Living Tissue

构建有血管的活组织的能力将使药物筛选、组织修复和再生方面取得关键进展。组织工程传统上依赖于无细胞支架的使用。然而，由于缺乏稳定的、可灌流的血管系统以及无法复制复杂的多细胞构型，这种方法极大地限制了可以创建的组织的大小和复杂性。血管网络是活组织的中心，因为所有细胞都必须位于营养供应的几百微米范围内才能生存。该奖项支持一种新的添加剂制造工艺的科学研究，该工艺用于制造由细胞、细胞外基质和嵌入的血管组成的三维、血管化的活组织。这项研究的结果将使3D活组织能够在制药行业中更广泛地用于药物安全性和毒性筛选，并最终用于组织修复和再生的药物中。这项研究将建立在器官规模上对血管化活组织进行生物打印所需的基本科学理解。印刷组织中细胞、细胞外基质和血管系统之间的复杂相互作用将被确定。这些关系将通过通过活/死染色来量化细胞活性来建立，作为不同细胞类型、浓度和细胞外基质组成的函数。血管网络结构的影响，包括血管的大小、间距和分支程度，对细胞活性和功能的影响也将通过活/死来量化，同时，血管通道的屏障功能将通过标准的渗漏测试作为不同的结构主题的函数来测量。最后，将确定不同细胞类型、浓度和细胞外基质组成的细胞负载墨水的喷嘴大小、设计和打印速度之间的关系，以确定在生物打印和长时间灌流期间促进最大细胞活力的必要条件，如活/死染色所确定的。

The ability to fabricate vascularized living tissues would enable critical advances in drug screening, tissue repair and regeneration. Tissue engineering has traditionally relied on the use of acellular scaffolds. However, this approach vastly limits the size and complexity of the tissues that can be created due to the lack of stable, perfusable vasculature and the inability to replicate intricate multicellular configurations. Vasculature networks are central to living tissues, since all cells must reside within several hundred micrometers of a nutrient supply to survive. This award supports scientific investigations on a new additive manufacturing process for fabricating three-dimensional, vascularized living tissues composed of cells, extracellular matrix, and embedded blood vessels. Results from this research will enable broader use of 3D living tissues in the pharmaceutical industry for drug safety and toxicity screening and, ultimately, in the medicine for tissue repair and regeneration.This research will establish the fundamental scientific understanding required for bioprinting of vascularized living tissue at organ scale. The complex interplay between cells, extracellular matrix, and vasculature in printed tissues will be determined. These relationships will be established by quantifying cell viability via live/dead staining as a function of varying cell type, concentration, and extracellular matrix composition. The effects of vascular network architecture, including blood vessel size, spacing, and degree of branching, on cell viability and function will also be quantified by live/dead and, concurrently, barrier function of the vascular channels will be measured by a standard leak test as a function of different architectural motifs. Finally, the relationship between nozzle size, design, and printing speed will be determined for cell-laden inks of varying cell type, concentration, and extracellular matrix composition to identify the requisite conditions that promote maximum cell viability, as determined by live/dead staining, during bioprinting and perfusion over long time periods.