Ohshima H, Ajima H, Kawano Y, Nozawa-Inoue K, Wakisaka S, Maeda T
Department of Oral Anatomy, Faculty of Dentistry, Niigata University, Gakkocho-dori, Japan.
Arch Histol Cytol. 2000 Oct;63(4):381-95. doi: 10.1679/aohc.63.381.
The expression of heat shock protein (Hsp) 25 during odontogenesis in the dental pulp and enamel organ of rat incisors was investigated by immunocytochemistry and confocal microscopy. In the process of dentin formation, immature odontoblasts first exhibited Hsp 25-immunoreactivity, and increased in immunointensity with the advance of their differentiation. In the dental pulp, in contrast, intense immunoreaction in the mesenchymal cells became weak or negative in parallel with the progress of cell differentiation. The immunoreaction for Hsp 25 in the enamel organ revealed a characteristic stage-related alteration during amelogenesis. In secretory ameloblasts, the immunoreaction for Hsp 25 was found throughout their cell bodies, intense reactivity being located near the proximal and distal terminal webs. At the maturation stage, ruffle-ended ameloblasts (RA) consistently showed Hsp 25-immunoreactivity throughout the cell bodies, whereas smooth-ended ameloblasts (SA) lacking a ruffled border were weak in immunoreaction at the distal cytoplasm. Other cellular elements of the enamel organ were negative. The subcellular localization of Hsp 25-immunoreactivity in this study appeared essentially identical to that of actin filaments as demonstrated by confocal microscopy using rhodamine-labeled phalloidin. These immunocytochemical data suggest that the Hsp 25 molecule is involved in reinforcement of the cell layer following cell movement during odontogenesis and in the formation and maintenance of the ruffled border of RA.
通过免疫细胞化学和共聚焦显微镜研究了大鼠切牙牙髓和釉质器官在牙发生过程中热休克蛋白（Hsp）25的表达。在牙本质形成过程中，未成熟的成牙本质细胞首先表现出Hsp 25免疫反应性，并随着其分化的进展免疫强度增加。相比之下，在牙髓中，间充质细胞中的强烈免疫反应随着细胞分化的进行而变弱或消失。釉质器官中Hsp 25的免疫反应在釉质形成过程中显示出与阶段相关的特征性变化。在分泌期成釉细胞中，在其整个细胞体中均发现Hsp 25免疫反应，强烈的反应位于近端和远端终末网附近。在成熟阶段，褶缘成釉细胞（RA）在整个细胞体中始终显示Hsp 25免疫反应性，而缺乏褶缘边界的平滑缘成釉细胞（SA）在远端细胞质中的免疫反应较弱。釉质器官的其他细胞成分均为阴性。本研究中Hsp 25免疫反应性的亚细胞定位与肌动蛋白丝的定位基本相同，这是通过使用罗丹明标记的鬼笔环肽的共聚焦显微镜证明的。这些免疫细胞化学数据表明，Hsp 25分子参与牙发生过程中细胞移动后细胞层的强化以及RA褶缘边界的形成和维持。
