State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, PR China.
PLoS One. 2013 Apr 19;8(4):e62332. doi: 10.1371/journal.pone.0062332. Print 2013.
Classical tooth development theory suggests that dental papilla cells (DPCs) are the precursor cells of odontoblasts, which are responsible for dentin development. However, our previous studies have indicated that dental follicle cells (DFCs) can differentiate into odontoblasts. To further our understanding of tooth development, and the differences in dentinogenesis between DFCs and DPCs, the odontogenic differentiation of DFCs and DPCs was characterized in vitro and in vivo. DFCs and DPCs were individually combined with treated dentin matrix (TDM) before they were subcutaneously implanted into the dorsum of mice for 8 weeks. Results showed that 12 proteins were significantly differential, and phosphoserine aminotransferase 1 (PSAT1), Isoform 2 of hypoxia-inducible factor 1-alpha (HIF1A) and Isoform 1 of annexin A2 (ANXA2), were the most significantly differential proteins. These proteins are related to regulation of bone balance, angiogenesis and cell survival in an anoxic environment. Both DFCs and DPCs express odontogenic, neurogenic and peridontogenic markers. Histological examination of the harvested grafts showed that both DFCs and DPCs form pulp-dentin/cementum-periodentium-like tissues in vivo. Hence, DFCs and DPCs have similar odontogenic differentiation potential in the presence of TDM. However, differences in glucose and amino acid metabolism signal transduction and protein synthesis were observed for the two cell types. This study expands our understanding on tooth development, and provides direct evidence for the use of alternative cell sources in tooth regeneration.
经典的牙齿发育理论认为，牙髓细胞（DPCs）是成牙本质细胞的前体细胞，后者负责牙本质的发育。然而，我们之前的研究表明，牙囊细胞（DFCs）可以分化为成牙本质细胞。为了进一步了解牙齿发育以及 DFCs 和 DPCs 之间牙本质发生的差异，我们在体外和体内研究了 DFCs 和 DPCs 的成牙本质分化。将 DFCs 和 DPCs 分别与处理后的牙本质基质（TDM）结合，然后将其皮下植入小鼠背部 8 周。结果表明，有 12 种蛋白质存在显著差异，其中磷酸丝氨酸氨基转移酶 1（PSAT1）、缺氧诱导因子 1-α同工型 2（HIF1A）和膜联蛋白 A2 同工型 1（ANXA2）的差异最为显著。这些蛋白质与骨平衡、血管生成和缺氧环境中细胞存活的调节有关。DFCs 和 DPCs 均表达成牙本质、神经生成和牙周生成标记物。对收获移植物的组织学检查表明，DFCs 和 DPCs 均可在体内形成牙髓-牙本质/牙骨质-牙周膜样组织。因此，在 TDM 的存在下，DFCs 和 DPCs 具有相似的成牙本质分化潜能。然而，两种细胞类型在葡萄糖和氨基酸代谢信号转导以及蛋白质合成方面存在差异。这项研究扩展了我们对牙齿发育的理解，并为牙齿再生中替代细胞来源的应用提供了直接证据。
