title: Maintained smoking cessation for 6 months equilibrates the percentage of sputum CD8+ lymphocyte cells with that of nonsmokers.
abstract: Little is known about the longitudinal effects of smoking cessation on sputum inflammatory cells. We aimed to investigate the changes in sputum inflammatory cells and T-lymphocyte subpopulations after 6 and 12 months smoking cessation. Induced sputum was obtained from 68 healthy smokers before and after 6 months (n = 21) and 1 year (n = 14) smoking cessation and from ten healthy never-smokers. Inflammatory cells were identified by morphology and T-lymphocyte subpopulations by flow cytometry. Sputum macrophages were decreased after 12 months of smoking cessation in comparison to baseline, while neutrophils increased. Moreover, CD8+ T-cells were decreased in smokers before smoking cessation compared to never-smokers and increased in smokers after 6 months of smoking cessation in comparison to baseline; result that was maintained after 1 year of smoking cessation. These novel findings indicate that smoking cessation can equilibrate certain inflammatory cells of smokers with those of nonsmokers, within 6 months of smoking cessation.
authors.affiliation: Department of Thoracic Medicine, University General Hospital, Medical School of the University of Crete, 71110 Heraklion, Greece. izolthi@yahoo.com
authors.forename: Izolde
authors.initials: I
authors.lastname: Bouloukaki
authors.forename: Maria
authors.initials: M
authors.lastname: Tsoumakidou
authors.forename: Constantine I
authors.initials: CI
authors.lastname: Vardavas
authors.forename: Ioanna
authors.initials: I
authors.lastname: Mitrouska
authors.forename: Eleni
authors.initials: E
authors.lastname: Koutala
authors.forename: Nikolaos M
authors.initials: NM
authors.lastname: Siafakas
authors.forename: Sophia E
authors.initials: SE
authors.lastname: Schiza
authors.forename: Nikos
authors.initials: N
authors.lastname: Tzanakis
mesh_terms: D000328:Adult; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D016540:Smoking Cessation; D013183:Sputum / Q000166:cytology / Q000276:immunology; D016176:T-Lymphocyte Subsets / Q000276:immunology*