title: Alterations of immune functions induced by 12C6+ ion irradiation in mice.
abstract: OBJECTIVE
  To estimate the biological risks to the immune system of the type of space radiation, 12C6+, encountered by cosmonauts during long-term travel in space.
  
  
  METHODS
  The Kun-Ming strain mice were whole-body irradiated by 12C6+ ion with 0, 0.01, 0.05, 0.075, 0.2, 0.3, 0.5, 0.75, 1 or 2 Gy, at a dose rate of 1 Gy/min. At 35 days after irradiation, the thymus and spleen weights were measured, the natural killer (NK) cells activity of spleen was determined by 3-(4, 5-dimethylthiazol-2-yl)- 2, 5-diphenyl tetrazolium bromide (MTT), and the interferon-gamma (IFN-gamma) levels in serum and thymus were detected with enzyme-linked immunosorbent assays (ELISA).
  
  
  RESULTS
  The results showed that the thymus weight, IFN-gamma levels in serum and the activity of splenic NK-cells had significantly increased at a dose of 0.05 Gy. With further dose increase, the weight of spleen continued to increase but the weight of thymus, IFN-gamma level and NK-cells activity declined.
  
  
  CONCLUSIONS
  These results suggest that the dose of 0.05 Gy irradiation has a stimulatory effect on mouse immunity; this effect declined with increasing dose.
authors.affiliation: Department of Radiology, Institute of Modern Physics, the Chinese Academy of Science, Lanzhou, Gansu Province, PR China.
authors.forename: Y
authors.initials: Y
authors.lastname: Xie
authors.forename: H
authors.initials: H
authors.lastname: Zhang
authors.forename: Y L
authors.initials: YL
authors.lastname: Wang
authors.forename: Q M
authors.initials: QM
authors.lastname: Zhou
authors.forename: R
authors.initials: R
authors.lastname: Qiu
authors.forename: Z G
authors.initials: ZG
authors.lastname: Yuan
authors.forename: G M
authors.initials: GM
authors.lastname: Zhou
mesh_terms: D000222:Adaptation, Physiological / Q000276:immunology / Q000528:radiation effects; D000818:Animals; D002244:Carbon; D016207:Cytokines / Q000276:immunology; D004307:Dose-Response Relationship, Radiation; D020450:Heavy Ions; D007107:Immune System / Q000276:immunology* / Q000528:radiation effects*; D007113:Immunity, Innate / Q000276:immunology* / Q000528:radiation effects*; D051379:Mice; D011829:Radiation Dosage; D013154:Spleen / Q000276:immunology / Q000528:radiation effects; D013950:Thymus Gland / Q000276:immunology / Q000528:radiation effects; D014916:Whole-Body Irradiation
chemical_list: D016207:Cytokines; D002244:Carbon