Kaneko Masahiro, Sato Airi, Ayano Satoru, Fujita Akio, Kobayashi Goro, Ito Akira
Department of Chemical Systems Engineering, School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan.
College of Bioscience and Biotechnology, Chubu University, 1200 Matsumoto, Kasugai, Aichi 487-8501, Japan.
J Biosci Bioeng. 2023 Nov;136(5):407-414. doi: 10.1016/j.jbiosc.2023.08.003. Epub 2023 Aug 30.
Microcarriers provide a high surface-area-to-volume ratio that can realize high yields of cell products, including human mesenchymal stem cells (hMSCs). Here, we report a novel poly(vinyl alcohol) (PVA)-based microcarrier for hMSC expansion in suspension culture. PVA microcarriers were prepared as collagen-coated PVA hydrogels 181 μm in size and a high surface-area-to-weight ratio of 2945 cm/g. The PVA microcarriers supported a 2.6-fold expansion of hMSCs in a 30-mL single-use stirred bioreactor after a 7 d culture period, comparable to that of commercially available microcarriers. Interestingly, we observed that hMSCs on PVA microcarriers adhered to adjacent microcarriers, resulting in the aggregation of hMSC-PVA microcarriers. Therefore, we conducted a long-term expansion culture using a bead-to-bead cell transfer method with PVA microcarriers. Fresh microcarriers were added to the cell-populated microcarriers in the bioreactor on days 7 and 14. hMSCs on PVA microcarriers continued to grow for 21 d using the bead-to-bead cell transfer method. Furthermore, magnetic PVA (PVA-mag) microcarriers were developed by loading magnetic nanoparticles into PVA microcarriers, and we demonstrated that these PVA-mag microcarriers enabled cell recovery by magnetic separation. These results suggest that these PVA microcarriers can contribute to the large-scale culture of hMSCs for regenerative medicine and cell therapy.
微载体具有高的表面积与体积比，能够实现包括人间充质干细胞（hMSCs）在内的细胞产物的高产量。在此，我们报道一种新型的基于聚乙烯醇（PVA）的微载体，用于在悬浮培养中扩增hMSCs。PVA微载体被制备成尺寸为181μm且表面积与重量比高达2945cm/g的胶原包被的PVA水凝胶。在30mL一次性搅拌生物反应器中培养7天后，PVA微载体支持hMSCs扩增2.6倍，与市售微载体相当。有趣的是，我们观察到PVA微载体上的hMSCs会粘附到相邻的微载体上，导致hMSC-PVA微载体聚集。因此，我们使用PVA微载体通过逐珠细胞转移法进行了长期扩增培养。在第7天和第14天，将新鲜的微载体添加到生物反应器中已接种细胞的微载体上。使用逐珠细胞转移法，PVA微载体上的hMSCs持续生长了21天。此外，通过将磁性纳米颗粒负载到PVA微载体中制备了磁性PVA（PVA-mag）微载体，并且我们证明这些PVA-mag微载体能够通过磁分离实现细胞回收。这些结果表明，这些PVA微载体有助于大规模培养用于再生医学和细胞治疗的hMSCs。
