title: Similar ex vivo expansion and post-irradiation regenerative potential of juvenile and aged salivary gland stem cells.
abstract: OBJECTIVE
  Salivary gland dysfunction is a major side effect of radiotherapy for head and neck cancer patients, which in the future might be salvaged by autologous adult salivary gland stem cell (SGSC) therapy. Since frail elderly patients may have decreased activity of SGSCs, we aimed to characterize the potential of aged SGSC-population in a murine model.
  
  
  METHODS
  Salivary glands and salisphere-derived cells from young and old mice were tested for CD24 and CD29 stem cell marker expression using FACS. Moreover, in vitro expansion capability and in vivo regeneration potential upon post-irradiation transplantation of young and aged SGSCs were measured.
  
  
  RESULTS
  An increase in CD24(hi)/CD29(hi) putative stem cells was detected in aged salivary glands albeit with a decrease in functional ability to form salispheres. However, the salispheres formed from aged mice salivary glands expressed CD24(hi)/CD29(hi) to the same extent as the ones from young mice. Moreover, following exposure to adequate growth conditions old and young SGSCs exhibited similar in vitro expansion- and in vivo regeneration potential.
  
  
  CONCLUSIONS
  Aged SGSCs although reduced in number are in vitro indistinguishable from young SGSCs and could potentially be used to ameliorate age- or treatment related salivary gland dysfunction.
authors.affiliation: Department of Cell Biology, University Medical Center Groningen, University of Groningen, The Netherlands; Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, The Netherlands.
authors.forename: Martti
authors.initials: M
authors.lastname: Maimets
authors.affiliation: Department of Cell Biology, University Medical Center Groningen, University of Groningen, The Netherlands.
authors.forename: Reinier
authors.initials: R
authors.lastname: Bron
authors.affiliation: Laboratory of Ageing Biology and Stem Cells, European Research Institute for the Biology of Aging (ERIBA), University Medical Center Groningen, University of Groningen, The Netherlands.
authors.forename: Gerald
authors.initials: G
authors.lastname: de Haan
authors.affiliation: Laboratory of Ageing Biology and Stem Cells, European Research Institute for the Biology of Aging (ERIBA), University Medical Center Groningen, University of Groningen, The Netherlands.
authors.forename: Ronald
authors.initials: R
authors.lastname: van Os
authors.affiliation: Department of Cell Biology, University Medical Center Groningen, University of Groningen, The Netherlands; Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, The Netherlands. Electronic address: r.p.coppes@umcg.nl.
authors.forename: Robert P
authors.initials: RP
authors.lastname: Coppes
mesh_terms: D000818:Animals; D051927:CD24 Antigen / Q000378:metabolism; D002478:Cells, Cultured; D016922:Cellular Senescence / Q000528:radiation effects*; D005260:Female; D019012:Integrin beta1 / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D012038:Regeneration / Q000528:radiation effects; D012469:Salivary Glands / Q000166:cytology / Q000502:physiology / Q000528:radiation effects*; D033581:Stem Cell Transplantation / Q000379:methods; D013234:Stem Cells / Q000528:radiation effects*
chemical_list: D051927:CD24 Antigen; D019012:Integrin beta1
keywords: Aging; Radiation-xerostomia; Regeneration; Salivary glands; Stem cells