Surfactant protein D is a candidate biomarker for subclinical tobacco smoke-induced lung damage

• Published in: American journal of physiology. Lung cellular and molecular physiology Vol. 306; no. 9; pp. L887 - L895
• Main Authors: Johansson, Sofie L, Tan, Qihua, Holst, René, Christiansen, Lene, Hansen, Niels C G, Hojland, Allan T, Wulf-Johansson, Helle, Schlosser, Anders, Titlestad, Ingrid L, Vestbo, Jørgen, Holmskov, Uffe, Kyvik, Kirsten O, Sorensen, Grith L
• Format: Journal Article
• Language: English
• Published: United States American Physiological Society 01.05.2014
• Subjects: Adolescent; Adult; Aged; Biomarkers - analysis; Cross-Sectional Studies; Denmark; Female; Forced Expiratory Volume; Genetic Association Studies; Haplotypes; Haplotypes - genetics; Humans; Lung Diseases - chemically induced; Lung Diseases - diagnosis; Lung Diseases - genetics; Male; Middle Aged; Polymorphism; Polymorphism, Single Nucleotide - genetics; Prognosis; Proteins; Pulmonary Surfactant-Associated Protein D - genetics; Pulmonary Surfactants - metabolism; Respiratory diseases; Risk assessment; Smoking - adverse effects; Surfactants; Tobacco smoke; Vital Capacity; Young Adult; Denmark; tobacco smoking; lung injury; single-nucleotide polymorphisms; surfactant protein D; forced expiratory volume in one second
• DOI: 10.1152/ajplung.00340.2013
• ISSN: 1040-0605

Variation in surfactant protein D (SP-D) is associated with lung function in tobacco smoke-induced chronic respiratory disease. We hypothesized that the same association exists in the general population and could be used to identify individuals sensitive to smoke-induced lung damage. The association between serum SP-D (sSP-D) and expiratory lung function was assessed in a cross-sectional design in a Danish twin population (n = 1,512, 18-72 yr old). The adjusted heritability estimates for expiratory lung function, associations between SP-D gene (SFTPD) single-nucleotide polymorphisms or haplotypes, and expiratory lung function were assessed using twin study methodology and mixed-effects models. Significant inverse associations were evident between sSP-D and the forced expiratory volume in 1 s and forced vital capacity in the presence of current tobacco smoking but not in nonsmokers. The two SFTPD single-nucleotide polymorphisms, rs1923536 and rs721917, and haplotypes, including these single-nucleotide polymorphisms or rs2243539, were inversely associated with expiratory lung function in interaction with smoking. In conclusion, SP-D is phenotypically and genetically associated with lung function measures in interaction with tobacco smoking. The obtained data suggest sSP-D as a candidate biomarker in risk assessments for subclinical tobacco smoke-induced lung damage. The data and derived conclusion warrant confirmation in a longitudinal population following chronic obstructive pulmonary disease initiation and development.