title: Occupational exposure to ionizing radiation has no effect on T- and B-cell total counts or percentages of helper, cytotoxic and activated T-cell subsets in the peripheral circulation of male radiation workers.
abstract: OBJECTIVE
  To investigate changes in immune cell subsets in the peripheral circulation of a male population occupationally exposed to ionizing radiation.
  
  
  METHODS
  Peripheral blood samples were taken from 194 male workers with cumulative exposures of >200 mSv (mean exposure 331.5 mSv, mean age 51 years) and from a reference population of 131 male workers with cumulative exposures of <27.5 mSv (mean exposure 13.9 mSv, mean age 47 years). Samples were analysed by flow cytometry for T- and B-cell total counts and for the T-cell subset percentages of CD4+ (helper T-cells), CD8+ (cytotoxic T-cells) and CD3+/HLA-DR+ (activated T-cells).
  
  
  RESULTS
  Comparison of the >200 and <27.5 mSv exposure groups using linear regression analysis showed no statistically significant differences between the two groups for T-cell total count, B-cell total count or for percentages of the T-cell subsets CD4+, CD8+ or CD3+/HLA-DR+ and CD4+:CD8+. However, statistically significant increases in both T- and B-cell total counts were observed within the two exposure groups and data pooled from both groups when non-smokers (never and ex-smokers) were compared with current smokers. For pooled data T-cell total count increased in smokers by 35% (p=0.0001) and B-cell total count increased by 37% (p=0.0004).
  
  
  CONCLUSIONS
  No significant immunological effects were observed in male radiation workers with cumulative exposures of >200 mSv when compared with a reference population with cumulative exposures of <27.5 mSv, although highly significant increases in both T- and B-cell total counts were observed in smokers compared with non-smokers.
authors.affiliation: Westlakes Research Institute, Westlakes Science and Technology Park, Moor Row, Cumbria CA24 3JY, UK. gwen.rees@westlakes.ac.uk
authors.forename: G S
authors.initials: GS
authors.lastname: Rees
authors.forename: C P
authors.initials: CP
authors.lastname: Daniel
authors.forename: S D
authors.initials: SD
authors.lastname: Morris
authors.forename: C A
authors.initials: CA
authors.lastname: Whitehouse
authors.forename: K
authors.initials: K
authors.lastname: Binks
authors.forename: D H
authors.initials: DH
authors.lastname: MacGregor
authors.forename: E J
authors.initials: EJ
authors.lastname: Tawn
mesh_terms: D000328:Adult; D001402:B-Lymphocytes / Q000528:radiation effects*; D006801:Humans; D008213:Lymphocyte Activation / Q000528:radiation effects; D018655:Lymphocyte Count; D008297:Male; D008875:Middle Aged; D016273:Occupational Exposure / Q000009:adverse effects*; D012907:Smoking / Q000276:immunology; D016176:T-Lymphocyte Subsets / Q000528:radiation effects; D013601:T-Lymphocytes / Q000528:radiation effects*