Utility of urinary Clara cell protein (CC16) to demonstrate increased lung epithelial permeability in non-smokers exposed to outdoor secondhand smoke.
The objective of this study was to assess the utility of urinary Clara cell protein (CC16) as a biomarker of increased lung epithelial permeability in non-smokers exposed to outdoor secondhand smoke. Twenty-eight healthy non-smoking adults visited outdoor patios of a restaurant and a bar where non-participants smoked and an open-air control with no smokers on three weekend days in a crossover study; subjects visited each site once for 3 h. Urine samples were collected at baseline, immediately post exposure and next morning, and analyzed for CC16. Changes in CC16 across location types or with cigarette count were analyzed using mixed-effect models, which included all subjects and stratified by gender. Urinary CC16 was higher in males (n=9) compared with females (n=18) at all measurement occasions (P<0.002), possibly reflecting prostatic contamination. Urinary CC16 from pre-exposure to post-exposure was higher following visits to restaurant and bar sites compared with the control among females but this increase did not reach statistical significance. Post-exposure to pre-exposure urinary CC16 ratios among females increased with cigarette count (P=0.048). Exposure-related increases in urinary CC16 were not seen among males. In conclusion, urinary CC16 may be a useful biomarker of increased lung epithelial permeability among female non-smokers; further work will be required to evaluate its applicability to males.
Department of Environmental Health Science, College of Public Health, University of Georgia, Athens, GA 30602-2102, USA.
Gideon
G
St Helen
Nina T
NT
Holland
John R
JR
Balmes
Daniel B
DB
Hall
J Thomas
JT
Bernert
John E
JE
Vena
Jia-Sheng
JS
Wang
Luke P
LP
Naeher
D015415:Biomarkers / Q000378:metabolism*; D002463:Cell Membrane Permeability; D018592:Cross-Over Studies; D004781:Environmental Exposure; D004847:Epithelial Cells / Q000378:metabolism; D006801:Humans; D008168:Lung / Q000166:cytology / Q000378:metabolism*; D014028:Tobacco Smoke Pollution; D014598:Uteroglobin / Q000378:metabolism*
D015415:Biomarkers; C556389:SCGB1A1 protein, human; D014028:Tobacco Smoke Pollution; D014598:Uteroglobin