Research data supporting 'Structurally graduated collagen scaffolds applied to the ex vivo generation of platelets from human pluripotent stem cell-derived megakaryocytes: enhancing production and purity'

Platelet transfusions are a key treatment option for a range of life threatening conditions including cancer, chemotherapy and surgery. Efficient ex vivo systems to generate donor independent platelets in clinically relevant numbers could provide a useful substitute. Large quantities of megakaryocytes (MKs) can be produced from human pluripotent stem cells, but in 2D culture the ratio of platelets harvested from MK cells has been limited and restricts production rate. The development of biomaterial cell supports that replicate vital hematopoietic micro-environment cues are one strategy that may increase in vitro platelet production rates from iPS derived Megakaryocyte cells. In this paper, we present the results obtained generating, simulating and using a novel structurally-graded collagen scaffold within a flow bioreactor system seeded with programmed stem cells. Theoretical analysis of porosity using micro-computed tomography analysis and synthetic micro-particle filtration provided a predictive tool to tailor cell distribution throughout the material. When used with MK programmed stem cells the graded scaffolds influenced cell location while maintaining the ability to continuously release metabolically active CD41+ CD42+ functional platelets. This scaffold design and novel fabrication technique offers a significant advance in understanding the influence of scaffold architectures on cell seeding, retention and platelet production.

血小板输注是针对癌症、化疗相关并发症及外科手术等多种危及生命病症的核心治疗手段。研发能够以临床相关规模制备供体非依赖性血小板的高效体外（ex vivo）系统，可成为极具价值的替代方案。人多能干细胞可诱导生成大量巨核细胞（megakaryocytes，MKs），但二维培养体系中，从巨核细胞收获的血小板比例受限，进而制约了整体产率。开发能够模拟关键造血微环境信号的生物材料细胞支架，是提升诱导多能干细胞（induced pluripotent stem cells，iPS）来源巨核细胞体外血小板产率的可行策略之一。本研究展示了在接种经编程干细胞的流动式生物反应器系统中，新型结构梯度型胶原支架的制备、模拟与应用所获实验结果。通过显微计算机断层扫描（micro-computed tomography）与合成微粒过滤法对支架孔隙率开展理论分析，可为精准调控细胞在支架内部的分布提供预测工具。当该梯度支架与巨核细胞定向干细胞配合使用时，可影响细胞在支架内的定位，同时能够持续释放具有代谢活性的CD41+、CD42+功能性血小板。该支架设计与新型制备工艺，为解析支架结构对细胞接种、细胞留存及血小板生成的影响提供了重要研究进展。