Innate Immunity of Airway Epithelium and COPD

摘要: The mammalian immune system consists of two branchesinnate and adaptive systems together they provide protection against infection. Innate immunity is a first line host defense responsible for immediate recognition pathogens to prevent microbial invasion. In addition innate responses also stimulate (Medzhitov Janeway, 1997). Cellular components include mucosal epithelial cells, macrophages, neutrophils, natural killer basophils, eosinophils others. airway mucosa represents the body’s largest surface point contact inhaled microorganisms, environmental pollutants, airborne allergens cigarette smoke (Diamond et al., 2000). Airway provides potentially hazardous factors by multiple mechanisms. For instance, mucus secreted epithelium covers apical traps particulate material. trapped material then cleared mucociliary escalator away from lungs towards pharynx. Tight junctions between polarized cells restrict paracellular movement solutes ions, gaining access submucosal compartment. its role as physical barrier internal milieu, play critical in bridging defenses (Hammad Lambrecht, 2011; Kato Schleimer, 2007). express number receptors known pattern molecules, which recognizes pathogen-associated molecular patterns (PAMPS) or danger-associated (DAMPS) initiate appropriate This includes elaboration antimicrobial proinflammatory cytokines chemokines that recruits activates other cells. activated lead recruitment into lumen responses. Continuous exposure stimuli, such smoke, noxious gases hazards may prolonged aberrant activation resulting excessive expression pro-inflammatory recruit large inflammatory lumen. turn leads persistent inflammation, damage abnormal repair, impaired There are reports suggesting