慢性阻塞性肺病、哮喘和囊性纤维化是不同的呼吸系统疾病，它们具有共同的特征，例如小 气道阻塞和急性发作。分泌型免疫球蛋白 A 作为一线黏膜保护屏障，可防止吸入颗粒和病原体。分泌型 IgA 可介导免疫排斥，并通过抑制病原体与上皮的黏附来促进病原体从气道表面的清除。sIgA 作为局部 黏膜免疫的主要成分，在慢性气道疾病中的具体免疫机制目前尚不清楚。本文就 sIgA 在慢性气道疾病中 的作用展开综述。

Chronic obstructive pulmonary disease，asthma and cystic fibrosis are distinct respiratory diseases that share features such as the obstruction of small airways and acute exacerbations.Secretory immunoglobulin A （sIgA）acts as a first⁃line mucosal protective barrier against inhaled particles and pathogens. sIgA mediates immune rejection and promotes clearance of pathogens from the airway surface by inhibiting adhesion of pathogens to the epithelium. sIgA is the main component of local mucosal immunity. The specific immune mechanism of sIgA in chronic airway diseases is still unclear. This article reviews the role of sIgA in chronic airway diseases.