Department of Bioengineering, University of California-Riverside, CA 92521, USA.
Nanofiber Solutions LLC, 1275 Kinnear Rd., Columbus, OH 43212, USA.
Biomaterials. 2015 May;50:10-9. doi: 10.1016/j.biomaterials.2015.01.037. Epub 2015 Feb 14.
The development of xeno-free, chemically defined stem cell culture systems has been a primary focus in the field of regenerative medicine to enhance the clinical application of pluripotent stem cells (PSCs). In this regard, various electrospun substrates with diverse physiochemical properties were synthesized utilizing various polymer precursors and surface treatments. Human induced pluripotent stem cells (IPSCs) cultured on these substrates were characterized by their gene and protein expression to determine the effects of the substrate physiochemical properties on the cells' self-renewal, i.e., proliferation and the maintenance of pluripotency. The results showed that surface chemistry significantly affected cell colony formation via governing the colony edge propagation. More importantly, when surface chemistry of the substrates was uniformly controlled by collagen conjugation, the stiffness of substrate was inversely related to the sphericity, a degree of three dimensionality in colony morphology. The differences in sphericity subsequently affected spontaneous differentiation of IPSCs during a long-term culture, implicating that the colony morphology is a deciding factor in the lineage commitment of PSCs. Overall, we show that the capability of controlling IPSC colony morphology by electrospun substrates provides a means to modulate IPSC self-renewal.
无血清化学成分确定的干细胞培养体系的发展一直是再生医学领域的主要关注点，旨在增强多能干细胞（PSCs）的临床应用。在这方面，利用各种聚合物前体和表面处理方法合成了具有不同物理化学性质的各种电纺基底。对在这些基底上培养的人诱导多能干细胞（iPSCs）进行基因和蛋白表达分析，以确定基底物理化学性质对细胞自我更新（即增殖和多能性维持）的影响。结果表明，表面化学通过控制菌落边缘的扩展显著影响细胞集落的形成。更重要的是，当通过胶原蛋白偶联均匀控制基底的表面化学性质时，基底的硬度与球形度呈反比关系，球形度是菌落形态的三维程度的度量。球形度的差异随后会影响 IPSC 在长期培养过程中的自发分化，表明菌落形态是 PSCs 谱系分化的决定因素。总的来说，我们表明，通过电纺基底控制 IPSC 菌落形态的能力为调节 IPSC 自我更新提供了一种方法。
