Department of Materials Engineering, School of Engineering, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
Department of Bioengineering, School of Engineering, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
J Mater Chem B. 2022 Apr 6;10(14):2561-2569. doi: 10.1039/d1tb01817e.
The effects of differentiated cells on stem cell differentiation were analyzed co-culturing using a cell-encapsulated double-layered hydrogel system. As a polymer hydrogel matrix, a water-soluble zwitterionic polymer having both a 2-methacryloyloxyethyl phosphorylcholine unit and a -vinylphenylboronic acid unit (PMBV), was complexed spontaneously with poly(vinyl alcohol) (PVA) under mild cell culture conditions. The creep modulus of the hydrogel was controlled by changing the composition of the polymer in the solution. Mouse mesenchymal stem cells (MSCs), C3H10T1/2 cells, were encapsulated into PMBV/PVA hydrogels and cultured. In the PMBV/PVA hydrogel with a lower creep modulus (0.40 kPa), proliferation of C3H10T1/2 cells occurred, and the formation of cell aggregates was observed. On the other hand, a higher creep modulus (1.7 kPa) of the hydrogel matrix prevented cell proliferation. Culturing C3H10T1/2 cells encapsulated in the PMBV/PVA hydrogel in the presence of bone morphogenetic protein-2 increased the activity of intracellular alkaline phosphatase (ALP). This indicated that C3H10T1/2 cells differentiated into mature osteoblasts. When the C3H10T1/2 cells encapsulated in the PMBV/PVA hydrogel were cultured in combination with the mature osteoblasts in the hydrogel by a close contacting double-layered hydrogel structure, higher ALP activity was observed compared with the cells cultured separately. It was considered that the differentiation of C3H10T1/2 cells in the hydrogel layer was induced by cytokines diffused from mature osteoblasts encapsulated in another hydrogel layer. It could be concluded that the PMBV/PVA hydrogel system provides a good way to observe the effects of the surrounding cells on cell function in three-dimensional culture.
采用细胞包封双层水凝胶系统，通过共培养分析分化细胞对干细胞分化的影响。作为聚合物水凝胶基质，将具有 2-甲基丙烯酰氧乙基膦酰胆碱单元和 -乙烯基苯硼酸单元（PMBV）的水溶性两性离子聚合物与聚乙烯醇（PVA）在温和的细胞培养条件下自发复合。通过改变溶液中聚合物的组成来控制水凝胶的蠕变模量。将小鼠间充质干细胞（MSCs）、C3H10T1/2 细胞包封到 PMBV/PVA 水凝胶中进行培养。在蠕变模量较低（0.40 kPa）的 PMBV/PVA 水凝胶中，C3H10T1/2 细胞增殖，并观察到细胞聚集体的形成。另一方面，水凝胶基质的较高蠕变模量（1.7 kPa）阻止了细胞增殖。在骨形态发生蛋白-2 的存在下培养包封在 PMBV/PVA 水凝胶中的 C3H10T1/2 细胞会增加细胞内碱性磷酸酶（ALP）的活性。这表明 C3H10T1/2 细胞分化为成熟成骨细胞。当将包封在 PMBV/PVA 水凝胶中的 C3H10T1/2 细胞在水凝胶中与水凝胶中成熟的成骨细胞紧密接触的双层水凝胶结构中培养时，与单独培养的细胞相比，观察到更高的 ALP 活性。可以认为，水凝胶层中 C3H10T1/2 细胞的分化是由包封在另一个水凝胶层中的成熟成骨细胞扩散的细胞因子诱导的。可以得出结论，PMBV/PVA 水凝胶系统为在三维培养中观察周围细胞对细胞功能的影响提供了一种很好的方法。
