title: Induction of gamma-H2AX foci in human exfoliated buccal cells after in vitro exposure to ionising radiation.
abstract: OBJECTIVE
  To test the gamma-H2AX (Histone 2AX phosphorylation of serine 139) foci assay for the detection of ionising radiation-induced DNA damage in buccal exfoliated cells.
  
  
  METHODS
  Buccal mucosa cells from five individuals (three females, two males, aged 26-47 years) were exposed to 0, 0.5, 1, 2 and 4 Gy of gamma-rays. DNA damage and DNA damage removal were measured using the gamma-H2AX foci assay. Lymphocytes from one donor and the nuclear antigen H2B were used as a positive control to test the staining protocol.
  
  
  RESULTS
  In the absence of radiation exposure, no significant differences for both H2B and gamma-H2AX signals were detected when comparing buccal cells and lymphocytes. The gamma-H2AX foci rate per cell in non-irradiated buccal cells was 0.08 +/- 0.02. The number of gamma-H2AX foci increased linearly with ionising radiation dose in the interval from 0-4 Gy, and reached a foci rate per cell of 0.82 +/- 0.22 at 4 Gy. Incubation experiments after in vitro gamma irradiation revealed that the number of gamma-H2AX foci did not show a significant decrease 5 h post exposure under the experimental conditions used.
  
  
  CONCLUSIONS
  Data suggest that it is possible to apply the gamma-H2AX foci assay for the detection of ionising radiation-induced DNA damage in buccal exfoliated cells. The low removal of ionising radiation induced gamma-H2AX foci in buccal cells is a potential advantage for a biological dosimetry application.
authors.affiliation: Centro de Protección e Higiene de las Radiaciones, La Habana, Cuba. jorgee@cphr.edu.cu
authors.forename: Jorge E
authors.initials: JE
authors.lastname: González
authors.forename: Sandrine H
authors.initials: SH
authors.lastname: Roch-Lefèvre
authors.forename: Tania
authors.initials: T
authors.lastname: Mandina
authors.forename: Omar
authors.initials: O
authors.lastname: García
authors.forename: Laurence
authors.initials: L
authors.lastname: Roy
mesh_terms: D000328:Adult; D002610:Cheek; D004249:DNA Damage; D005260:Female; D006657:Histones / Q000032:analysis*; D006801:Humans; D008297:Male; D009061:Mouth Mucosa / Q000737:chemistry / Q000473:pathology / Q000528:radiation effects*
chemical_list: C468783:H2AX protein, human; D006657:Histones