Immunodetection of benzo[a]pyrene adducts in ovarian cells of women exposed to cigarette smoke

Benzo[a]-pyrene (B[a]P) is a potent mutagen and carcinogen present in cigarettes. We report here on immunodetection and quantification of B[a]P-DNA adducts in granulosa-lutein cells of patients undergoing in-vitro fertilization (IVF) and embryo transfer, who were exposed to cigarette smoke, Follicular fluids (FF) and granulosa-lutein cells were obtained from the same follicular aspirate from 32 women self-reported as active smokers, passive smokers, or non-smokers. Cells were immunostained with 5D11, an anti-B[a]P diolepoxide monoclonal antibody that recognizes DNA adducts. Cotinine, a reliable marker for recent smoke exposure and dose, was assessed by radioimmunoassay in 32 FF samples. Individual scores of cell immunoreactivity were highly correlated with FF cotinine concentrations. Evaluations of immunostaining intensity in 9770 granulosa-lutein cells from the 32 women revealed higher average scores in active and passive smokers, relative to non-smokers. In passive smokers the average level of cell immunostaining was 63% of that of active smokers. These relationships provide quantitative evidence that B[a]P-DNA adduct levels are related to smoke exposure and dose, both recent and long term. Immunostaining was confined to the nucleus, suggesting adduct formation by covalent binding to DNA. Presence of adducts in granulosa-lutein cells from women exposed to cigarette smoke may increase the risk for DNA damage.