Shanghai Key Laboratory of Multiphase Materials Chemical Engineering, Department of Product Engineering, School of Chemical Engineering, East China University of Science and Technology, No.130 Mei Long Road, Shanghai 200237, China.
State Key Laboratory of Bioreactor Engineering, School of Bioengineering, East China University of Science and Technology, No.130 Mei Long Road, Shanghai 200237, China.
Int J Biol Macromol. 2022 Sep 1;216:1-13. doi: 10.1016/j.ijbiomac.2022.06.173. Epub 2022 Jun 28.
Human umbilical cord mesenchymal stem cells (HUMSCs) are one of the most attractive sources of stem cells, and it is meaningful to design and develop a type of microcarriers with suitable mechanical strength for HUMSCs proliferation in order to acquire enough cells for cell-based therapy. Alginate-gelatin core-shell (AG) soft microcarriers were thus fabricated via a microfluidic device with droplet shearing/gelation facilities and surface coating for in vitro expansion of HUMSCs. The attachment and proliferation of HUMSCs on AG microcarriers with different mechanical strengths modulated by gelatin coating was studied, and the harvested cells were characterized to verity their differentiation potential. The obtained core-shell microcarriers were all uniform in size with a high mono-dispersity (CV < 5 %). An increase in the gelatin surface coating concentration from 0.5 % to 1.5 % would lead to the reduction in both the particle size of the microcarriers and swelling ratio upon the contact of culture medium, but increased elastic modulus. Microcarriers of 245.12 μm with a gelatin coating elastic modulus of 27.5 kPa (AG10) were found to be the optimal substrate for HUMSCs with an initial attachment efficiency of 44.41 % and a 5-day expansion efficiency of 647 %. The cells harvested from AG10 still reserved their outstanding pluripotency. Fresh AG10 could smoothly transfer cells from a running microcarrier-cell system of confluence to serve as a convenient way of scaling-up the existing culture. The current study thus developed suitable microcarriers, AG10, for in vitro HUMSCs expansion with well reserve of cell multipotency, and also provided a manufacturing and surface manipulating strategy of precise production and fine regulation of microcarrier properties.
人脐带间充质干细胞（HUMSCs）是最有吸引力的干细胞来源之一，设计和开发一种具有适当机械强度的微载体对于 HUMSCs 的增殖具有重要意义，以便获得足够的细胞用于基于细胞的治疗。因此，通过具有液滴剪切/凝胶化设施和表面涂层的微流控装置，制造了藻酸盐-明胶核壳（AG）软微载体，用于 HUMSCs 的体外扩增。研究了不同机械强度的明胶涂层调节的 AG 微载体上 HUMSCs 的附着和增殖，并对收获的细胞进行了特征分析以验证其分化潜能。所得到的核壳微载体的尺寸均一，具有高单分散性（CV<5%）。明胶表面涂层浓度从 0.5%增加到 1.5%会导致微载体的粒径和与培养基接触时的溶胀比减小，但弹性模量增加。具有 27.5kPa 明胶涂层弹性模量的 245.12μm 微载体（AG10）被发现是 HUMSCs 的最佳基质，初始附着效率为 44.41%，5 天扩增效率为 647%。从 AG10 收获的细胞仍然保留了其出色的多能性。新鲜的 AG10 可以顺利地将细胞从汇合的运行微载体-细胞系统中转移出来，成为扩大现有培养的一种方便方法。因此，本研究开发了合适的微载体 AG10，用于 HUMSCs 的体外扩增，具有良好的细胞多能性储备，并提供了一种制造和表面处理策略，用于精确生产和精细调节微载体性能。
