文摘
Poly(ethylene glycol)-poly(l-alanine) diblock copolymer (PEG-L-PA; molecular weight of each block of 1000鈥?080 Da) aqueous solutions undergo sol-to-gel transition in a 3.0鈥?.0 wt % concentration range as the temperature increases. By incorporating the polystyrene microspheres with different functional groups with a size of 100鈥?00 渭m in in situ formed PEG-L-PA thermogels, the differentiation of tonsil-tissue-derived mesenchymal stem cells (TMSCs) was investigated. The mRNA expression and immunohistochemical assays suggested that the TMSCs preferentially undergo adipogenesis in the ammonium (鈭扤H<sub>3sub><sup>+sup>)- or thiol (鈭扴H)-functionalized microsphere incorporated thermogels; chondrogenesis in the thiol-, phosphate (PO<sub>3sub><sup>2鈥?/sup>)-, or carboxylate (鈭扖OO<sup>鈥?/sup>)-functionalized microsphere incorporated thermogels; and osteogenesis in the phosphate-, carboxylate-functionalized, or neat polystyrene microsphere incorporated thermogels. This paper provides a new TMSC 3D culture system of a sol鈥揼el reversible matrix and suggests that the surface-functional groups of microspheres in the thermogel can control the preferential differentiation of stem cells into specific cell types during the 3D culture.