目的牙齿萌出时,源于成釉器的缩余釉上皮与口腔上皮细胞融合为上皮团形成牙齿的软组织萌出通道,本研究对细胞角蛋白14在这一过程中的表达进行组织学定位,从而探讨其可能作用。方法不同发育期SPF级BALB/c小鼠9只。循环内固定后分别双侧下颌骨10%EDTA脱钙30d,常规脱水包埋,近远中向5μm连续切片,行苏木精-伊红和免疫组化染色。PV免疫组化两步法检测细胞角蛋白14和细胞增殖核抗原在各组织的表达。结果牙齿萌出过程中口腔上皮对细胞角蛋白14呈现时空特异性表达,非牙齿萌出部位的口腔上皮仅基底层阳性表达细胞角蛋白14,而萌出牙齿冠方的口腔上皮阳性表达则较广泛;缩余釉上皮在牙齿萌出过程中始终阳性表达细胞角蛋白14,而且伴随缩余釉上皮和口腔上皮融合的发生,缩余釉上皮的外层细胞和口腔上皮的基底层和基底上层细胞呈现细胞角蛋白14强阳性表达。结论细胞角蛋白14与牙齿萌出软组织通道的形成密切相关,可作为缩余釉上皮相关研究的上皮性标记物。
Objective To study the expression of eytokeratin 14 in reduced enamel epithelium and oral epithelium during tooth eruption so as to explore the roles of cytokeratin 14. Methods Nine BALB/c postnatal mice of different developing stages were applied to observe the erup- tion of mandibular teeth by light microscopy; PV two steps immunohistochemical method was used to localize the distribution of cytokeratin 14 and PCNA (proliferating cell nuclear antigen) timely and spatially. Results There was a temporospatial expression of eytokeratin 14 in oral epithelium during tooth eruption. The expression of cytokeratin 14 was different in oral epithelium over the erupting tooth from that not over the erupting tooth, but positive expression of cytokeratin 14 could constantly be observed in reduced enamel epithelium during tooth eruption. Conclusion Epithelial remodeling of reduced enamel epithelium and oral epithelium plays a crucial role in teeth eruption, in which eytokeratin 14 may have important roles.