Abstract:

Objective: Cytokeratin 14(K14) is the marker of salivary gland stem/progenitor cells. This study aimed to explore the expression and role of K14⁺ during the injury and regeneration process of the submandibular gland (SMG). Methods: The main salivary gland ducts of 8-week-old mice were ligated for 14-d and then deligated. The mice were sacrificed at 0-d, 14-d after ligation and 3-d, 28-d, 56-d after deligation. The injury and regeneration of SMG were observed by histological staining, and the proliferation of K14⁺ cells was observed by immunofluorescence staining. The mRNA expression level and changes of genes related to salivary gland function were detected by real-time PCR. Results: Mouse SMG duct ligation-deligation model was successfully established. The number of K14⁺ cells gradually decreased over time during the development period of the SMG. The glands showed atrophy and the duct showed dilatation after the main duct was ligated; the number of K14⁺ cells increased in the early stage of SMG regeneration, and most of them were in a proliferating state; but the expression level of genes related to salivary gland function was low. Conclusion: During the injury and regeneration process of the SMG, the expression of K14⁺ cells increased in the early stage during regeneration, suggesting that K14⁺ cells are involved in the regeneration process of the SMG.

Key words: submandibular gland, injury, regeneration, cytokeratin 14

摘要：

目的：角蛋白14（cytokeratin 14, K14）是唾液腺干/祖细胞的标志物，本研究探讨K14⁺细胞在下颌下腺损伤修复中表达分布的特征。方法：构建8周龄小鼠双侧下颌下腺主导管结扎-开放模型，分别于结扎后0、14 d及开放后3、28、56 d收样，利用组织学染色法评估下颌下腺损伤及再生状况，免疫荧光染色法观察K14⁺细胞增殖，实时荧光定量PCR检测唾液腺功能相关基因表达的变化。结果：在下颌下腺发育过程中K14⁺细胞随着年龄增长逐渐减少；成功构建小鼠下颌下腺主导管结扎-开放模型，导管结扎后，腺体萎缩，导管扩张；开放导管后，腺体修复早期K14⁺细胞数目增多，增殖活跃，但是唾液腺功能相关基因表达较低。结论：在下颌下腺损伤修复早期K14⁺细胞表达增加，提示K14⁺细胞参与了下颌下腺损伤修复的过程。

关键词: 下颌下腺, 损伤, 再生, 角蛋白14