Hepatogenic Supported Differentiation of Mesenchymal Stem Cells in a Lactobionic Acid-Conjugated Thermogel

To investigate the effect of receptor substrate of target cells on stem cell differentiation, lactobionic acid-conjugated poly[(propylene glycol)-b-(ethylene glycol)-b-(propylene glycol)]-poly(l-alanine) (LB-PLX-PA) was synthesized, and then thermogelling systems consisting of LB-PLX-PA and PLX-PA in a ratio of 0/100 (LB-0), 5/95 (LB-5), and 20/80 (LB-20) were constructed as an injectable three-dimensional scaffold toward hepatogenic differentiation of tonsil-derived mesenchymal stem cells (TMSCs). Modulus of LB-0, LB-5, and LB-20 increased to 500-800 Pa at 37 °C (gel) due to the heat induced sol-to-gel transition of the systems during which TMSCs were incorporated into the gel. Based on biomarker expressions and hepatic biofunctions of the differentiated cells, the receptor substrate (LB)-conjugated bioactive thermogel provides compatible microenvironments for the differentiated cells, and thus gives pronounced positive results on the differentiation of the stem cells into target cells during three-dimensional culture, compared with a passive thermogel.