Sonoyama W, Seo B-M, Yamaza T, Shi S
Center for Craniofacial Molecular Biology, University of Southern California School of Dentistry, Los Angeles, CA 90033, USA.
J Dent Res. 2007 Jul;86(7):594-9. doi: 10.1177/154405910708600703.
Hertwig's epithelial root sheath (HERS) cells are a unique population of epithelial cells in the periodontal ligament compartment. To date, their functional role has not been fully elucidated. Our hypothesis was that HERS cells may be involved in regulating differentiation of periodontal ligament stem cells (PDLSCs) and forming cementum in vivo. In this study, we found that HERS cells may be capable of promoting PDLSC differentiation and undergoing epithelial-mesenchymal transition in vitro. Immunohistochemical staining, Western blot analysis, a transwell co-culture system, and in vivo transplantation were used to characterize the interplay between HERS cells and PDLSCs, as well as the epithelial-mesenchymal transition (EMT) of HERS cells. TGFbeta1 was capable of inducing the epithelial-mesenchymal transition of HERS cells through activating the PI3K/AKT pathway. Furthermore, HERS cells were able to form cementum-like tissue when transplanted into immunocompromised mice.
bone marrow mesenchymal stem cell, BMMSC; bone sialoprotein, BSP; hydroxyapatite/tricalcium phosphate, HA/TCP; Hertwig's epithelial root sheath, HERS; osteocalcin, OCN; periodontal ligament, PDL; periodontal ligament stem cell, PDLSC; phosphatidylinositol 3-kinase, PI3K.
赫特维希上皮根鞘（HERS）细胞是牙周膜隔室中独特的上皮细胞群体。迄今为止，它们的功能作用尚未完全阐明。我们的假设是，HERS细胞可能参与调节牙周膜干细胞（PDLSCs）的分化并在体内形成牙骨质。在本研究中，我们发现HERS细胞在体外可能能够促进PDLSC分化并经历上皮-间充质转化。免疫组织化学染色、蛋白质印迹分析、Transwell共培养系统和体内移植用于表征HERS细胞与PDLSCs之间的相互作用以及HERS细胞的上皮-间充质转化（EMT）。转化生长因子β1（TGFbeta1）能够通过激活PI3K/AKT途径诱导HERS细胞的上皮-间充质转化。此外，HERS细胞移植到免疫缺陷小鼠体内时能够形成类牙骨质组织。
骨髓间充质干细胞，BMMSC；骨涎蛋白，BSP；羟基磷灰石/磷酸三钙，HA/TCP；赫特维希上皮根鞘，HERS；骨钙素，OCN；牙周膜，PDL；牙周膜干细胞，PDLSC；磷脂酰肌醇3-激酶，PI3K。
