title: Helium-neon laser irradiation promotes the proliferation and migration of human epidermal stem cells in vitro: proposed mechanism for enhanced wound re-epithelialization.
abstract: OBJECTIVE
  The present study was conducted to investigate the effects of helium-neon (He-Ne) laser irradiation on the proliferation, migration, and differentiation of cultured human epidermal stem cells (ESCs).
  
  
  BACKGROUND
  A He-Ne laser with a wavelength of 632.8 nm is known to have photobiological effects, and is widely used for accelerating wound healing; however, the cellular mechanisms involved have not been completely understood.
  
  
  METHODS
  The ESCs were prepared from human foreskin, and irradiated by using He-Ne laser at 632.8 nm with 2 J/cm(2). The ESC proliferation, migration, and differentiation were examined by using XTT assay, scratch assay, and flow cytometry technology, respectively. The phosphorylation of extracellular signal-regulated kinases (ERK) was analyzed by using Western blotting.
  
  
  RESULTS
  He-Ne laser irradiation markedly promoted cell proliferation and migration accompanied by an increase in the phosphorylation of ERK, but did not significantly influence cell differentiation.
  
  
  CONCLUSIONS
  Our data indicated that photostimulation with a He-Ne laser resulted in a significant increase in human ESC proliferation and migration in vitro, which might contribute, at least partially, to accelerated wound re-epithelialization by low-level laser therapy.
authors.affiliation: 1 Department of Plastic Surgery, The First Affiliated Hospital of Jinan University , Key Laboratory of Regenerative Medicine, Ministry of Education, Guangzhou, Guangdong Province, P.R. China .
authors.forename: Xuan
authors.initials: X
authors.lastname: Liao
authors.forename: Guang-Hui
authors.initials: GH
authors.lastname: Xie
authors.forename: Hong-Wei
authors.initials: HW
authors.lastname: Liu
authors.forename: Biao
authors.initials: B
authors.lastname: Cheng
authors.forename: Sheng-Hong
authors.initials: SH
authors.lastname: Li
authors.forename: Shan
authors.initials: S
authors.lastname: Xie
authors.forename: Li-Ling
authors.initials: LL
authors.lastname: Xiao
authors.forename: Xiao-Bing
authors.initials: XB
authors.lastname: Fu
mesh_terms: D002465:Cell Movement / Q000528:radiation effects; D049109:Cell Proliferation / Q000528:radiation effects; D002648:Child; D000078404:Epidermal Cells; D006801:Humans; D066298:In Vitro Techniques; D054020:Lasers, Gas / Q000627:therapeutic use; D028022:Low-Level Light Therapy; D062326:Re-Epithelialization / Q000528:radiation effects*; D013234:Stem Cells / Q000528:radiation effects*; D014945:Wound Healing / Q000528:radiation effects