Kaneko Ryuta, Akita Hirotoshi, Shimauchi Hidetoshi, Sasano Yasuyuki
Division of Periodontology and Endodontology, Tohoku University Graduate School of Dentistry, Sendai, Japan.
J Electron Microsc (Tokyo). 2009 Dec;58(6):363-73. doi: 10.1093/jmicro/dfp029. Epub 2009 Jun 12.
STRO-1 is a cell-surface antigen. A cell population that is positive for the anti-STRO-1 antibody has been shown to contain mesenchymal stem cells. STRO-1-positive cells have been reported to reside in dental pulp and periodontal ligaments as well as in bone marrow. However, the tissue localization of STRO-1 in developing teeth is not clear. The present study was designed to investigate the spatiotemporal localization of STRO-1 in developing rat teeth by immunohistochemistry using light microscopy and electron microscopy. Wistar rats at ages 2, 3, 6 and 12 weeks postnatum and embryos at 18 days postcoitum were fixed with 4% paraformaldehyde. Mandibles and maxillae were resected and decalcified in 10% EDTA. The specimens were embedded in paraffin, and sections were cut and processed for immunohistochemistry using the anti-STRO-1 antibody. Selected specimens were frozen, sectioned and processed for immunoelectron microscopy. Immunoreactions for STRO-1 were identified in some bone marrow cells. Some odontoblasts and dental pulp cells showed positive immunoreactivity in developing rat tooth crowns and roots. Alveolar osteoblasts, cementoblasts and periodontal ligament cells were also immunoreactive. Electron microscopy localized the antigen in plasma membrane and some vesicles in dental pulp cells and odontoblasts. The study suggests that the STRO-1 antigen is involved in the differentiation of mesenchymal cell lineages and formation of the matrix in dental tissues.
STRO-1是一种细胞表面抗原。已证明抗STRO-1抗体呈阳性的细胞群体含有间充质干细胞。据报道，STRO-1阳性细胞存在于牙髓、牙周韧带以及骨髓中。然而，STRO-1在发育中牙齿的组织定位尚不清楚。本研究旨在通过使用光学显微镜和电子显微镜的免疫组织化学方法，研究STRO-1在发育中大鼠牙齿的时空定位。将出生后2、3、6和12周的Wistar大鼠以及受孕后18天的胚胎用4%多聚甲醛固定。切除下颌骨和上颌骨，并在10%乙二胺四乙酸（EDTA）中脱钙。将标本嵌入石蜡中，切片并使用抗STRO-1抗体进行免疫组织化学处理。选择的标本进行冷冻、切片并进行免疫电子显微镜处理。在一些骨髓细胞中鉴定出STRO-1的免疫反应。一些成牙本质细胞和牙髓细胞在发育中的大鼠牙冠和牙根中显示出阳性免疫反应性。牙槽成骨细胞、成牙骨质细胞和牙周韧带细胞也具有免疫反应性。电子显微镜将抗原定位在牙髓细胞和成牙本质细胞的质膜和一些小泡中。该研究表明，STRO-1抗原参与间充质细胞谱系的分化和牙齿组织中基质的形成。
