Cao X M, Huang Q P, Chen S S
Bioengineering College of Chongqing University, Key Laboratory of Biorheological Science and Technology (Chongqing University), Ministry of Education, Chongqing 400044, China.
Zhonghua Gan Zang Bing Za Zhi. 2019 Jun 20;27(6):424-429. doi: 10.3760/cma.j.issn.1007-3418.2019.06.007.
To explore the effect of substrate mechanical microenvironment and cell-cell interaction on differentiation of bone marrow mesenchymal stem cells (BMSCs), intrahepatic cellular function and phenotype. Bone marrow mesenchymal stem cells (BMSCs)-hepatocytes (HCs) and BMSCs-hepatic stellate cells (HSCs) were co-cultured on polyvinyl alcohol (PVA) hydrogel substrates at different stiffness (4.50 ± 0.47 kPa, 19.00 ± 3.51 kPa and 37.00 ± 2.09 kPa) by non-contact co-culture method. Furthermore, the effect of substrate mechanical microenvironment on BMSCs, HCs and HSCs and the activation and proliferation of HCs under different co-cultured condition was studied. A Student's t-test was used to compare the two groups. The expression ofα-smooth muscle actin (α-SMA) and collagenα1- I (Col1A1) in BMSCs and HSCs cultured on its own increased with increase of substrate stiffness. After 72 h, the expression of albumin (ALB) of HCs on three stiff substrates was significantly higher than that of 24 and 48 h. Moreover, the expression of ALB of HCs increased with the increase of substrate stiffness. During the co-culture of BMSCs and HSCs, BMSCs of all three stiffness substrates promoted the expression ofα-SMA, Col1A1 in HSCs, but reduced the expression of PPARγin HSCs cells, thererby promoted the activation of HSCs, with apparent stiffness at 37 kPa. HSCs promoted the expression of ABL in BMSCs at three stiff substrates, but inhibited the expression of alpha-SMA and Col1A1 in BMSCs at 37 kPa, suggesting that co-culture had inhibited the differentiation of BMSCs myofibroblasts, and promoted the differentiation of hepatocyte-like cells, especially at high stiff substrates. In the co-culture of BMSCs and hepatic parenchymal cells, BMSCs had promoted the proliferation of hepatic parenchymal cells at 4.5 kPa. Further, hepatic parenchymal cells had inhibited the expression ofα-SMA in BMSCs, and promoted the expression of Alb, with inhibition of BMSCs differentiation towards myofibroblasts. The differentiation of BMSCs affects the substrate mechanical microenvironment, co-culture of HCs and HSCs. Simultaneously, affecting the function of hepatocytes in relation to the mechanical state of the substrates.
为探讨基质力学微环境及细胞间相互作用对骨髓间充质干细胞（BMSCs）分化、肝内细胞功能及表型的影响。采用非接触共培养方法，将骨髓间充质干细胞（BMSCs）与肝细胞（HCs）、骨髓间充质干细胞与肝星状细胞（HSCs）在不同硬度（4.50±0.47 kPa、19.00±3.51 kPa和37.00±2.09 kPa）的聚乙烯醇（PVA）水凝胶基质上共培养。此外，研究了基质力学微环境对BMSCs、HCs和HSCs的影响以及不同共培养条件下HCs的活化和增殖情况。采用Student's t检验比较两组数据。单独培养的BMSCs和HSCs中α-平滑肌肌动蛋白（α-SMA）和Ⅰ型胶原α1（Col1A1）的表达随基质硬度增加而升高。72小时后，三种硬度基质上HCs的白蛋白（ALB）表达显著高于24小时和48小时。此外，HCs的ALB表达随基质硬度增加而升高。在BMSCs与HSCs共培养过程中，三种硬度基质的BMSCs均促进了HSCs中α-SMA、Col1A1的表达，但降低了HSCs细胞中PPARγ的表达，从而促进了HSCs的活化，在37 kPa时硬度效应明显。HSCs促进了三种硬度基质上BMSCs中ABL的表达，但在37 kPa时抑制了BMSCs中α-SMA和Col1A1的表达，表明共培养抑制了BMSCs向肌成纤维细胞的分化，促进了肝样细胞的分化，尤其是在高硬度基质上。在BMSCs与肝实质细胞共培养中，BMSCs在4.5 kPa时促进了肝实质细胞的增殖。此外，肝实质细胞抑制了BMSCs中α-SMA的表达，促进了Alb的表达，抑制了BMSCs向肌成纤维细胞的分化。BMSCs的分化影响基质力学微环境、HCs与HSCs的共培养。同时，影响肝细胞功能与基质力学状态的关系。
