Takahashi Ken, Shimonishi Mitsuru, Wang Rui, Watanabe Hiroatsu, Kikuchi Masahiko
Division of Comprehensive Dentistry, Tohoku University Graduate School of Dentistry, Sendai, Japan.
Eur J Oral Sci. 2012 Dec;120(6):475-83. doi: 10.1111/j.1600-0722.2012.01002.x. Epub 2012 Oct 8.
Epithelial-mesenchymal interactions influence morphogenesis and cell differentiation in periodontal tissue regeneration. The current study examined the expression of amelogenin, ameloblastin, matrix metallopeptidase-20 (MMP-20), and kallikrein-4 (KLK-4) and their effects on the interactions between the epithelial cells of Malassez and periodontal ligament fibroblasts. Explants of human periodontal ligament tissues produced outgrowths containing both the epithelial cells of Malassez and periodontal ligament fibroblasts after incubation in a modified serum-free medium. Both the epithelial cells and fibroblasts were co-cultured in the same dish. The distribution and expression of all four factors were evaluated using immunohistochemistry, in-situ hybridization and RT-PCR analysis. The epithelial cells of Malassez were cultured separately and were used as the control. Immunohistochemical analysis revealed weak expression of amelogenin, ameloblastin, MMP-20 and KLK-4 in epithelial cells of Malassez co-cultured with periodontal ligament fibroblasts. in-situ hybridization and RT-PCR confirmed significant mRNA expression of these factors in co-cultured cells compared with control cells. MMP20 mRNA was not expressed in control cells. These results suggest that the epithelial-mesenchymal interactions promote differentiation of human epithelial cells of Malassez and that the induction of enamel matrix proteases facilitates the degradation of enamel matrix proteins.
上皮-间充质相互作用影响牙周组织再生中的形态发生和细胞分化。本研究检测了釉原蛋白、成釉蛋白、基质金属蛋白酶-20（MMP-20）和激肽释放酶-4（KLK-4）的表达及其对马拉瑟上皮细胞与牙周膜成纤维细胞之间相互作用的影响。人牙周膜组织外植体在改良无血清培养基中培养后，长出的组织含有马拉瑟上皮细胞和牙周膜成纤维细胞。上皮细胞和成纤维细胞在同一培养皿中共培养。使用免疫组织化学、原位杂交和逆转录-聚合酶链反应（RT-PCR）分析评估所有四种因子的分布和表达。将马拉瑟上皮细胞单独培养并用作对照。免疫组织化学分析显示，与牙周膜成纤维细胞共培养的马拉瑟上皮细胞中，釉原蛋白、成釉蛋白、MMP-20和KLK-4表达较弱。原位杂交和RT-PCR证实，与对照细胞相比，共培养细胞中这些因子的mRNA表达显著。对照细胞中未表达MMP20 mRNA。这些结果表明，上皮-间充质相互作用促进了人马拉瑟上皮细胞的分化，并且釉质基质蛋白酶的诱导促进了釉质基质蛋白的降解。
