title: Flow cytometry as a quantitative and sensitive method to evaluate low dose radiation induced apoptosis in vitro in human peripheral blood lymphocytes.
abstract: Human peripheral blood lymphocytes, irradiated in vitro, die by an apoptotic process. The number of apoptotic cells after in vitro gamma-irradiation (0, 0.1, 0.2, 1, 2 and 5 Gy) was measured by flow cytometry using Annexin V and DiOC6 (a cationic dye) after 24 and 48 h incubation. The mean dose-response curves for apoptosis of six healthy volunteers obtained with both methods were steep below 1 Gy and flatter at higher doses. A slightly higher number of apoptotic cells was observed with DiOC6, compared to Annexin V. This can be assigned to a minor DiOC6-int/PI- population. Forty-eight hour cultures contained higher numbers of apoptotic cells compared with 24 h cultures. For both culture times, DiOC6 and Annexin V detected a statistically significant difference between a control sample and a 0.1 Gy irradiated one, illustrating the high sensitivity of the methods.
authors.affiliation: Department of Anatomy, Embryology and Histology, University of Ghent, Belgium.
authors.forename: K
authors.initials: K
authors.lastname: Hertveldt
authors.forename: J
authors.initials: J
authors.lastname: Philippé
authors.forename: H
authors.initials: H
authors.lastname: Thierens
authors.forename: M
authors.initials: M
authors.lastname: Cornelissen
authors.forename: A
authors.initials: A
authors.lastname: Vral
authors.forename: L
authors.initials: L
authors.lastname: De Ridder
mesh_terms: D017304:Annexin A5; D017209:Apoptosis / Q000528:radiation effects*; D002232:Carbocyanines; D002478:Cells, Cultured; D004307:Dose-Response Relationship, Radiation; D005434:Flow Cytometry / Q000379:methods; D016650:Fluorescein-5-isothiocyanate; D005456:Fluorescent Dyes; D005720:Gamma Rays; D006801:Humans; D007700:Kinetics; D008214:Lymphocytes / Q000473:pathology / Q000528:radiation effects*; D011994:Recombinant Proteins; D012680:Sensitivity and Specificity
chemical_list: D017304:Annexin A5; D002232:Carbocyanines; D005456:Fluorescent Dyes; D011994:Recombinant Proteins; C007392:3,3'-dihexyl-2,2'-oxacarbocyanine; D016650:Fluorescein-5-isothiocyanate