Biological effectiveness of accelerated particles for the induction of chromosome damage measured in metaphase and interphase human lymphocytes.
Chromosome aberrations were investigated in human lymphocytes after in vitro exposure to 1H-, 3He-, 12C-, 40Ar-, 28Si-, 56Fe-, or 197Au-ion beams, with LET ranging from approximately 0.4-1393 keV/microm in the dose range of 0.075-3 Gy. Dose-response curves for chromosome exchanges, measured at the first mitosis postirradiation using fluorescence in situ hybridization (FISH) with whole-chromosome probes, were fitted with linear or linear-quadratic functions. The relative biological effectiveness (RBE) was estimated from the initial slope of the dose-response curve for chromosomal damage with respect to low- or high-dose-rate gamma rays. Estimates of RBEmax values for mitotic spreads, which ranged from near 0.7 to 11.1 for total exchanges, increased with LET, reaching a maximum at about 150 keV/microm, and decreased with further increase in LET. RBEs for complex aberrations are undefined due to the lack of an initial slope for gamma rays. Additionally, the effect of mitotic delay on RBE values was investigated by measuring chromosome aberrations in interphase after chemically induced premature chromosome condensation (PCC), and values were up to threefold higher than for metaphase analysis.
George
Kerry
K
Wyle Laboratories, 1290 Hercules Drive, Houston, Texas 77058, USA. Kerry.A.George1@jsc.nasa.gov
Durante
Marco
M
Willingham
Veronica
V
Wu
Honglu
H
Yang
Tracy C
TC
Cucinotta
Francis A
FA
D002869:Chromosome Aberrations; D002877:Chromosomes, Human / Q000528:radiation effects* / Q000648:ultrastructure*; D004307:Dose-Response Relationship, Radiation; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007399:Interphase / Q000528:radiation effects; D018499:Linear Energy Transfer; D008214:Lymphocytes / Q000166:cytology* / Q000528:radiation effects*; D008677:Metaphase / Q000528:radiation effects; D011829:Radiation Dosage; D012062:Relative Biological Effectiveness