Department of Medicine, Pulmonary Division, University of Helsinki and Helsinki University Central Hospital, Helsinki, Finland.
Eur Respir J. 2011 Aug;38(2):277-84. doi: 10.1183/09031936.00110510. Epub 2011 Jan 27.
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.
血清表面活性蛋白（SP）-A 被认为与肺纤维化有关，但它在与吸烟有关的肺部疾病中的作用尚不清楚。使用经过验证的 EIA 方法评估了非吸烟者、有呼吸道症状（咳嗽和/或咳痰）的吸烟者和无症状吸烟者的血浆和诱导痰中的 SP-A 水平。共纳入了 474 名无任何疾病或药物的当前吸烟者，并对他们进行了 2 年的随访，其中 111 人成功戒烟。与不吸烟者相比，所有受试者的血浆 SP-A 水平均可检测到，且吸烟者无论症状如何均升高（p = 0.001）。经过 2 年的随访，继续吸烟者的 SP-A 水平高于戒烟者（p<0.001）。血浆 SP-A 水平与年龄、吸烟史和肺功能有关。在大多数非吸烟者的痰中未检测到痰（n = 109）SP-A，而吸烟和症状使痰 SP-A 显著升高（p = 0.001）。总之，SP-A 可能参与了与吸烟有关的肺部疾病的发病机制。需要进一步的研究来阐明 SP-A 在慢性阻塞性肺疾病中的作用。
