Mikami Yoshikazu, Yamamoto Kiyofumi, Akiyama Yuko, Kobayashi Masayuki, Watanabe Eri, Watanabe Nobukazu, Asano Masatake, Shimizu Noriyoshi, Komiyama Kazuo
1 Department of Pathology, Nihon University School of Dentistry , Tokyo, Japan .
Stem Cells Dev. 2015 Jan 15;24(2):214-27. doi: 10.1089/scd.2014.0060.
An analytical study of cell-cell communications between murine osteoblast-like MLO-A5 cells and bone marrow mesenchymal stem cell (BMSC)-like C3H10T1/2 cells was performed. C3H10T1/2 cells expressing green fluorescent protein (10T-GFP cells) were generated to enable the isolation of the BMSC-like cells from co-cultures with MLO-A5 cells. The mRNA expression levels of several osteogenic transcription factors (Runx2, Osterix, Dlx5, and Msx2) did not differ between the co-cultured and mono-cultured 10T-GFP cells, but those of alkaline phosphatase (ALP) and bone sialoprotein (BSP) were 300- to 400-fold higher in the co-cultured cells. Patch clamp and biocytin transfer assays revealed gap junction-mediated communication between co-cultured 10T-GFP and MLO-A5 cells. The addition of a gap junction inhibitor suppressed the increases in the expression levels of the ALP and BSP mRNAs in co-cultured 10T-GFP cells. Furthermore, the histone acetylation levels were higher in co-cultured 10T-GFP cells than in mono-cultured 10T-GFP cells. These results suggest that osteoblasts and BMSCs associate via gap junctions, and that gap junction-mediated signaling induces histone acetylation that leads to elevated transcription of the genes encoding ALP and BSP in BMSCs.
对小鼠成骨细胞样MLO - A5细胞与骨髓间充质干细胞样C3H10T1/2细胞之间的细胞间通讯进行了分析研究。构建了表达绿色荧光蛋白的C3H10T1/2细胞（10T - GFP细胞），以便从与MLO - A5细胞的共培养物中分离出骨髓间充质干细胞样细胞。共培养和单培养的10T - GFP细胞中几种成骨转录因子（Runx2、Osterix、Dlx5和Msx2）的mRNA表达水平没有差异，但共培养细胞中碱性磷酸酶（ALP）和骨唾液蛋白（BSP）的mRNA表达水平高出300至400倍。膜片钳和生物素转移试验揭示了共培养的10T - GFP和MLO - A5细胞之间存在间隙连接介导的通讯。添加间隙连接抑制剂可抑制共培养的10T - GFP细胞中ALP和BSP mRNA表达水平的升高。此外，共培养的10T - GFP细胞中的组蛋白乙酰化水平高于单培养的10T - GFP细胞。这些结果表明，成骨细胞和骨髓间充质干细胞通过间隙连接相互作用，并且间隙连接介导的信号传导诱导组蛋白乙酰化，从而导致骨髓间充质干细胞中编码ALP和BSP的基因转录升高。
