The osteopontin (OPN) released from mesenchymal stem cells (MSCs) undergoing lineage differentiation can negatively influence the expansion of hematopoietic stem cells (HSCs) in coculture systems developed for expanding HSCs. Therefore, minimizing the amount of OPN in the coculture system is important for the successful ex vivo expansion of HSCs. Toward this goal, a bioengineered three dimensional (3D) microfibrous-matrix that can maintain MSCs in less OPN-releasing conditions has been developed, and its influence on the expansion of HSCs has been studied. The newly developed 3D matrix significantly decreased the release of OPN, depending on the MSC culture conditions used during the priming period before HSC seeding. The culture system with the lowest amount of OPN facilitated a more than 24-fold increase in HSC number in 1 week time period. Interestingly, the viability of expanded cells and the CD34⁺ pure population of HSCs were found to be the highest in the low OPN-containing system. Therefore, bioengineered microfibrous 3D matrices seeded with MSCs, primed under suitable culture conditions, can be an improved ex vivo expansion system for HSC culture.

中文翻译：

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生物工程 3D 微纤维基质调节 MSC 释放骨桥蛋白并促进造血干细胞的扩增

从进行谱系分化的间充质干细胞 (MSCs) 释放的骨桥蛋白 (OPN) 会对为扩增 HSCs 而开发的共培养系统中造血干细胞 (HSCs) 的扩增产生负面影响。因此，最大限度地减少共培养系统中 OPN 的数量对于 HSC 的成功体外扩增非常重要。为了实现这一目标，已经开发出一种生物工程三维 (3D) 微纤维基质，可以在较少 OPN 释放条件下维持 MSC，并研究了其对 HSC 扩张的影响。新开发的 3D 基质显着降低了 OPN 的释放，这取决于在 HSC 播种前的启动期使用的 MSC 培养条件。OPN 含量最低的培养系统在 1 周时间内促进了 HSC 数量增加 24 倍以上。⁺发现 HSC 的纯种群在低 OPN 含量系统中最高。因此，在合适的培养条件下接种 MSCs 的生物工程微纤维 3D 基质可以成为 HSC 培养的改进的离体扩增系统。