title: Analysis of white blood cell counts in mice after gamma- or proton-radiation exposure.
abstract: In the coming decades human space exploration is expected to move beyond low-Earth orbit. This transition involves increasing mission time and therefore an increased risk of radiation exposure from solar particle event (SPE) radiation. Acute radiation effects after exposure to SPE radiation are of prime importance due to potential mission-threatening consequences. The major objective of this study was to characterize the dose-response relationship for proton and γ radiation delivered at doses up to 2 Gy at high (0.5 Gy/min) and low (0.5 Gy/h) dose rates using white blood cell (WBC) counts as a biological end point. The results demonstrate a dose-dependent decrease in WBC counts in mice exposed to high- and low-dose-rate proton and γ radiation, suggesting that astronauts exposed to SPE-like radiation may experience a significant decrease in circulating leukocytes.
authors.affiliation: Department of Radiation Oncology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA.
authors.forename: Casey J
authors.initials: CJ
authors.lastname: Maks
authors.forename: X Steven
authors.initials: XS
authors.lastname: Wan
authors.forename: Jeffrey H
authors.initials: JH
authors.lastname: Ware
authors.forename: Ana L
authors.initials: AL
authors.lastname: Romero-Weaver
authors.forename: Jenine K
authors.initials: JK
authors.lastname: Sanzari
authors.forename: Jolaine M
authors.initials: JM
authors.lastname: Wilson
authors.forename: Steve
authors.initials: S
authors.lastname: Rightnar
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Wroe
authors.forename: Peter
authors.initials: P
authors.lastname: Koss
authors.forename: Daila S
authors.initials: DS
authors.lastname: Gridley
authors.forename: James M
authors.initials: JM
authors.lastname: Slater
authors.forename: Ann R
authors.initials: AR
authors.lastname: Kennedy
mesh_terms: D000818:Animals; D004307:Dose-Response Relationship, Radiation; D023381:Endpoint Determination; D005260:Female; D005720:Gamma Rays / Q000009:adverse effects*; D007958:Leukocyte Count; D007962:Leukocytes / Q000166:cytology* / Q000528:radiation effects*; D051379:Mice; D008813:Mice, Inbred ICR; D011522:Protons / Q000009:adverse effects*; D012062:Relative Biological Effectiveness
chemical_list: D011522:Protons