title: Human salivary gland stem/progenitor cells remain dormant even after irradiation.
abstract: Progressive loss of salivary gland function occurs in most patients undergoing head and neck radiotherapy. It is unclear whether adult salivary gland tissue contains stem/progenitor cells. In this study, we used a colony assay to clarify the presence of stem/progenitor cells in adult submandibular glands after irradiation. We developed a novel culture system that promotes single-cell colony formation with low density culture of irradiated and non-irradiated adult human submandibular gland cells using serum-free medium following serum-supplemented medium. The cells from all samples, except those obtained from the oldest patient who received the highest radiation dose, expressed acinar, ductal, and myoepithelial cell-lineage markers with reverse transcription-polymerase chain reaction (RT-PCR) and immunostaining. A sub-culture of these colonies with serum-free medium showed high multipotency. These results are the first description of presence of salivary gland stem/progenitor cells with self-renewal, high proliferation and multipotent differentiation activity in salivary glands, even after irradiation. The survival of the cells depends on radiation dose and cell aging.
authors.affiliation: Department of Oral and Maxillofacial Surgery, Yokohama City Iniversity Graduate School of Medicine, Yokohama 232-0024, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Tatsuishi
authors.forename: Makoto
authors.initials: M
authors.lastname: Hirota
authors.forename: Teruki
authors.initials: T
authors.lastname: Kishi
authors.forename: Makoto
authors.initials: M
authors.lastname: Adachi
authors.forename: Takafumi
authors.initials: T
authors.lastname: Fukui
authors.forename: Kenji
authors.initials: K
authors.lastname: Mitsudo
authors.forename: Shinjiro
authors.initials: S
authors.lastname: Aoki
authors.forename: Yoshiro
authors.initials: Y
authors.lastname: Matsui
authors.forename: Susumu
authors.initials: S
authors.lastname: Omura
authors.forename: Hideki
authors.initials: H
authors.lastname: Taniguchi
authors.forename: Iwai
authors.initials: I
authors.lastname: Tohnai
mesh_terms: D000368:Aged; D015415:Biomarkers / Q000378:metabolism; D019070:Cell Lineage; D002469:Cell Separation; D002478:Cells, Cultured; D002999:Clone Cells; D003114:Colony-Forming Units Assay; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D012469:Salivary Glands / Q000166:cytology* / Q000528:radiation effects*; D013194:Staining and Labeling; D013234:Stem Cells / Q000166:cytology* / Q000528:radiation effects*; D013363:Submandibular Gland / Q000166:cytology
chemical_list: D015415:Biomarkers