Department of Oral and Maxillofacial Surgery, School of Dentistry, Showa University, Tokyo, 142-8555, Japan; Division of Pathology, Department of Oral Diagnostic Sciences, School of Dentistry, Showa University, Tokyo, 142-8555, Japan.
Division of Pathology, Department of Oral Diagnostic Sciences, School of Dentistry, Showa University, Tokyo, 142-8555, Japan.
Biochem Biophys Res Commun. 2022 Jan 1;586:55-62. doi: 10.1016/j.bbrc.2021.11.064. Epub 2021 Nov 19.
Salivary gland hypofunction due to radiation therapy for head and neck cancer or Sjögren syndrome may cause various oral diseases, which can lead to a decline in the quality of life. Cell therapy using salivary gland stem cells is a promising method for restoring hypofunction. Herein, we show that salivary gland-like cells can be induced from epithelial tissues that were transdifferentiated from mouse embryonic fibroblasts (MEFs). We introduced four genes, Dnp63a, Tfap2a, Grhl2, and Myc (PTMG) that are known to transdifferentiate fibroblasts into oral mucosa-like epithelium in vivo into MEFs. MEFs overexpressing these genes showed epithelial cell characteristics, such as cobblestone appearance and E-cadherin positivity, and formed oral epithelial-like tissue under air-liquid interface culture conditions. The epithelial sheet detached from the culture dish was infected with adenoviruses encoding Sox9 and Foxc1, which we previously identified as essential factors to induce salivary gland formation. The cells detached from the cell sheet formed spheres 10 days after infection and showed a branching morphology. The spheres expressed genes encoding basal/myoepithelial markers, cytokeratin 5, cytokeratin 14, acinar cell marker, aquaporin 5, and the myoepithelial marker α-smooth muscle actin. The dissociated cells of these primary spheres had the ability to form secondary spheres. Taken together, our results provide a new strategy for cell therapy of salivary glands and hold implications in treating patients with dry mouth.
由于头颈部癌症或干燥综合征的放射治疗导致唾液腺功能低下，可能会引起各种口腔疾病，从而导致生活质量下降。利用唾液腺干细胞的细胞疗法是恢复功能低下的有前途的方法。在此，我们展示了可以从已经转分化为小鼠胚胎成纤维细胞（MEF）的上皮组织中诱导出唾液腺样细胞。我们将已知在体内将成纤维细胞转分化为口腔黏膜样上皮的四个基因（Dnp63a、Tfap2a、Grhl2 和 Myc，即 PTMG）导入 MEF。这些基因过表达的 MEF 表现出上皮细胞特征，如鹅卵石外观和 E-钙黏蛋白阳性，并在气液界面培养条件下形成口腔上皮样组织。从培养皿中分离出的上皮片被编码 Sox9 和 Foxc1 的腺病毒感染，我们之前已经确定这两种基因是诱导唾液腺形成的必需因素。从细胞片中分离出的细胞在感染后 10 天形成球体，并表现出分支形态。这些球体表达编码基底/肌上皮标记物、细胞角蛋白 5、细胞角蛋白 14、腺泡细胞标记物、水通道蛋白 5 和肌上皮标记物α-平滑肌肌动蛋白的基因。这些初级球体的分离细胞具有形成次级球体的能力。总之，我们的结果为唾液腺的细胞治疗提供了一种新策略，并对治疗口干症患者具有重要意义。
