Bals R, Hiemstra P S
Dept of Internal Medicine, Division of Pulmonary Medicine, Hospital of the University of Marburg, Philipps-University, Marburg, Germany.
Eur Respir J. 2004 Feb;23(2):327-33. doi: 10.1183/09031936.03.00098803.
The human lung is exposed to a large number of airborne pathogens as a result of the daily inhalation of 10,000 litres of air. The observation that respiratory infections are nevertheless rare is testimony to the presence of an efficient host defence system at the mucosal surface of the lung. The airway epithelium is strategically positioned at the interface with the environment, and thus plays a key role in this host defence system. Recognition systems employed by airway epithelial cells to respond to microbial exposure include the action of the toll-like receptors. The airway epithelium responds to such exposure by increasing its production of mediators such as cytokines, chemokines and antimicrobial peptides. Recent findings indicate the importance of these peptides as effector molecules of innate immunity by killing microorganisms, but also as regulators of inflammation, immunity and wound repair. Finally, the clinical relevance of the functions of the airway epithelium in innate immunity is discussed.
由于每天吸入10000升空气，人类肺部会接触到大量空气传播的病原体。然而，呼吸道感染却很少见，这证明肺部黏膜表面存在高效的宿主防御系统。气道上皮细胞位于与外界环境的交界处，因此在这个宿主防御系统中起着关键作用。气道上皮细胞用于应对微生物暴露的识别系统包括Toll样受体的作用。气道上皮细胞通过增加细胞因子、趋化因子和抗菌肽等介质的产生来应对这种暴露。最近的研究结果表明，这些肽不仅作为先天性免疫的效应分子通过杀死微生物发挥作用，而且还作为炎症、免疫和伤口修复的调节因子。最后，讨论了气道上皮细胞在先天性免疫中的功能的临床相关性。
