Wongin Sopita, Ogawa Yuuki, Kim Mee-Hae, Viravaidya-Pasuwat Kwanchanok, Kino-Oka Masahiro
Biological Engineering Program, Faculty of Engineering, King Mongkut's University of Technology Thonburi, Bangkok, 10140, Thailand.
Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka, 565-0871, Japan.
Biotechnol Lett. 2017 Aug;39(8):1253-1261. doi: 10.1007/s10529-017-2339-9. Epub 2017 Apr 12.
To investigate the behaviors of aggregates of human mesenchymal stem cells (hMSCs) on chondrogenesis and chondrocyte hypertrophy using spatiotemporal expression patterns of chondrogenic (type II collagen) and hypertrophic (type X collagen) markers during chondrogenesis.
hMSCs were cultured on either a polystyrene surface or polyamidoamine dendrimer surface with a fifth generation (G5) dendron structure in chondrogenic medium and growth medium. At day 7, cell aggregates without stress fibers formed on the G5 surface and triggered differentiation of hMSCs toward the chondrogenic fate, as indicated by type II collagen being observed while type X collagen was undetectable. In contrast, immunostaining of hMSCs cultured on polystyrene, which exhibited abundant stress fibers and did not form aggregates, revealed no evidence of either type II and or type X collagen. At day 21, the morphological changes of the cell aggregates formed on the G5 surface were suppressed as a result of stress fiber formation. Type II collagen was observed throughout the aggregates whereas type X collagen was detected only at the basal side of the aggregates. Change of cell aggregate behaviors derived from G5 surface alone regulated chondrogenesis and hypotrophy, and this was enhanced by chondrogenic medium.
Incubation of hMSCs affects the expression of type II and X collagens via effects on cell aggregate behavior and stress fiber formation.
利用软骨形成过程中软骨生成（II型胶原蛋白）和肥大（X型胶原蛋白）标志物的时空表达模式，研究人间充质干细胞（hMSCs）聚集体在软骨形成和软骨细胞肥大方面的行为。
将hMSCs在软骨形成培养基和生长培养基中培养于聚苯乙烯表面或具有第五代（G5）树枝状结构的聚酰胺胺树枝状大分子表面。在第7天，G5表面形成了没有应力纤维的细胞聚集体，并触发了hMSCs向软骨生成命运的分化，表现为可观察到II型胶原蛋白，而未检测到X型胶原蛋白。相比之下，在聚苯乙烯上培养的hMSCs进行免疫染色，其显示出丰富的应力纤维且未形成聚集体，未发现II型和X型胶原蛋白的证据。在第21天，由于应力纤维的形成，G5表面形成的细胞聚集体的形态变化受到抑制。整个聚集体中都观察到II型胶原蛋白，而仅在聚集体的基底侧检测到X型胶原蛋白。仅源自G5表面的细胞聚集体行为变化调节软骨形成和肥大，并且软骨形成培养基可增强这种调节作用。
hMSCs的培养通过影响细胞聚集体行为和应力纤维形成来影响II型和X型胶原蛋白的表达。
