title: Identification of gene-based responses in human blood cells exposed to alpha particle radiation.
abstract: BACKGROUND
  The threat of a terrorist-precipitated nuclear event places humans at danger for radiological exposures. Isotopes which emit alpha (α)-particle radiation pose the highest risk. Currently, gene expression signatures are being developed for radiation biodosimetry and triage with respect to ionizing photon radiation. This study was designed to determine if similar gene expression profiles are obtained after exposures involving α-particles.
  
  
  METHODS
  Peripheral blood mononuclear cells (PBMCs) were used to identify sensitive and robust gene-based biomarkers of α-particle radiation exposure. Cells were isolated from healthy individuals and were irradiated at doses ranging from 0-1.5 Gy. Microarray technology was employed to identify transcripts that were differentially expressed relative to unirradiated cells 24 hours post-exposure. Statistical analysis identified modulated genes at each of the individual doses.
  
  
  RESULTS
  Twenty-nine genes were common to all doses with expression levels ranging from 2-10 fold relative to control treatment group. This subset of genes was further assessed in independent complete white blood cell (WBC) populations exposed to either α-particles or X-rays using quantitative real-time PCR. This 29 gene panel was responsive in the α-particle exposed WBCs and was shown to exhibit differential fold-changes compared to X-irradiated cells, though no α-particle specific transcripts were identified.
  
  
  CONCLUSIONS
  Current gene panels for photon radiation may also be applicable for use in α-particle radiation biodosimetry.
authors.affiliation: Consumer and Clinical Radiation Protection Bureau, Healthy Environment and Consumer Safety Branch, Health Canada, 775 Brookfield Road, PL 6303B, Ottawa, ON K1A 1C1, Canada. Vinita.chauhan@hc-sc.gc.ca.
authors.forename: Vinita
authors.initials: V
authors.lastname: Chauhan
authors.forename: Matthew
authors.initials: M
authors.lastname: Howland
authors.forename: Ruth
authors.initials: R
authors.lastname: Wilkins
mesh_terms: D000512:Alpha Particles / Q000009:adverse effects*; D004249:DNA Damage; D004307:Dose-Response Relationship, Radiation; D005260:Female; D023281:Genomics; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000378:metabolism* / Q000528:radiation effects*; D008297:Male; D035683:MicroRNAs / Q000235:genetics; D059467:Transcriptome / Q000528:radiation effects*; D014965:X-Rays
chemical_list: D035683:MicroRNAs