Identification of regulatory factors for mesenchymal stem cell-derived salivary epithelial cells in a co-culture system.
Patients with Sjögren's syndrome or head and neck cancer patients who have undergone radiation therapy suffer from severe dry mouth (xerostomia) due to salivary exocrine cell death. Regeneration of the salivary glands requires a better understanding of regulatory mechanisms by which stem cells differentiate into exocrine cells. In our study, bone marrow-derived mesenchymal stem cells were co-cultured with primary salivary epithelial cells from C57BL/6 mice. Co-cultured bone marrow-derived mesenchymal stem cells clearly resembled salivary epithelial cells, as confirmed by strong expression of salivary gland epithelial cell-specific markers, such as alpha-amylase, muscarinic type 3 receptor, aquaporin-5, and cytokeratin 19. To identify regulatory factors involved in this differentiation, transdifferentiated mesenchymal stem cells were analyzed temporarily by two-dimensional-gel-electrophoresis, which detected 58 protein spots (>1.5 fold change, p<0.05) that were further categorized into 12 temporal expression patterns. Of those proteins only induced in differentiated mesenchymal stem cells, ankryin-repeat-domain-containing-protein 56, high-mobility-group-protein 20B, and transcription factor E2a were selected as putative regulatory factors for mesenchymal stem cell transdifferentiation based on putative roles in salivary gland development. Induction of these molecules was confirmed by RT-PCR and western blotting on separate sets of co-cultured mesenchymal stem cells. In conclusion, our study is the first to identify differentially expressed proteins that are implicated in mesenchymal stem cell differentiation into salivary gland epithelial cells. Further investigation to elucidate regulatory roles of these three transcription factors in mesenchymal stem cell reprogramming will provide a critical foundation for a novel cell-based regenerative therapy for patients with xerostomia.
Department of Oral and Maxillofacial Diagnostic Sciences, University of Florida College of Dentistry, Gainesville, Florida, United States of America.
Yun-Jong
YJ
Park
Interdisciplinary Center for Biotechnology Research, University of Florida, Gainesville, Florida, United States of America.
Jin
J
Koh
Department of Oral and Maxillofacial Diagnostic Sciences, University of Florida College of Dentistry, Gainesville, Florida, United States of America.
Adrienne E
AE
Gauna
Interdisciplinary Center for Biotechnology Research, University of Florida, Gainesville, Florida, United States of America; Department of Biology, UF Genetics Institute, University of Florida, Gainesville, Florida, United States of America; Genetics Institute, University of Florida, Gainesville, Florida, United States of America.
Sixue
S
Chen
Department of Oral and Maxillofacial Diagnostic Sciences, University of Florida College of Dentistry, Gainesville, Florida, United States of America.
Seunghee
S
Cha
D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D054338:Cell Transdifferentiation; D018920:Coculture Techniques; D019295:Computational Biology; D004847:Epithelial Cells / Q000166:cytology / Q000378:metabolism*; D008297:Male; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000378:metabolism*; D051379:Mice; D020543:Proteome; D040901:Proteomics / Q000379:methods; D012469:Salivary Glands / Q000166:cytology*; D014157:Transcription Factors / Q000378:metabolism
D015415:Biomarkers; D020543:Proteome; D014157:Transcription Factors