title: Elevation of surfactant protein A in plasma and sputum in cigarette smokers.
abstract: Serum surfactant protein (SP)-A has been postulated to associate with pulmonary fibrosis, but its role in cigarette smoking-related lung diseases is undefined. SP-A levels in plasma and induced sputum in nonsmokers, smokers with respiratory symptoms (cough and/or phlegm) and symptom-free smokers were assessed using a validated EIA method. A total of 474 current smokers without any diseases or medications were enrolled and followed for 2 yrs with 111 of them succeeding in stopping. Plasma SP-A level was detectable in all subjects and elevated in smokers independently of the symptoms compared to nonsmokers (p = 0.001). After 2 yrs of follow-up, the SP-A level was higher in those who continued smoking compared to the quitters (p<0.001). Plasma SP-A levels were associated with age, smoking history and lung function. Sputum (n = 109) SP-A was nondetectable in most nonsmokers, whereas smoking and symptoms increased sputum SP-A highly significantly (p = 0.001). In conclusion, SP-A may be involved in pathogenesis of cigarette smoking-related lung diseases. Further studies are needed to elucidate the role of SP-A in chronic obstructive pulmonary disease.
authors.affiliation: Department of Medicine, Pulmonary Division, University of Helsinki and Helsinki University Central Hospital, Helsinki, Finland.
authors.forename: W
authors.initials: W
authors.lastname: Mazur
authors.forename: T
authors.initials: T
authors.lastname: Toljamo
authors.forename: S
authors.initials: S
authors.lastname: Ohlmeier
authors.forename: K
authors.initials: K
authors.lastname: Vuopala
authors.forename: P
authors.initials: P
authors.lastname: Nieminen
authors.forename: H
authors.initials: H
authors.lastname: Kobayashi
authors.forename: V L
authors.initials: VL
authors.lastname: Kinnula
mesh_terms: D000367:Age Factors; D000368:Aged; D003371:Cough / Q000139:chemically induced / Q000503:physiopathology; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008168:Lung / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D037662:Pulmonary Surfactant-Associated Protein A / Q000097:blood*; D012129:Respiratory Function Tests; D012907:Smoking / Q000097:blood*; D016540:Smoking Cessation; D013183:Sputum / Q000737:chemistry*
chemical_list: D037662:Pulmonary Surfactant-Associated Protein A