Role of airway epithelial cells in development of asthma and allergic rhinitis

Department of Pulmonary Medicine, Zhongshan Hospital, Fudan University, Shanghai 20032, China.
Respiratory Medicine (Impact Factor: 3.09). 08/2008; 102(7):949-55. DOI: 10.1016/j.rmed.2008.01.017
Source: PubMed


Asthma and allergic rhinitis frequently coexist in the same patient. There is a similarity and variation as well as potential relationship between asthma and allergic rhinitis. There is an increasing evidence to suggest a major involvement of airway epithelial cells in the pathogenesis of asthma and allergic rhinitis. The present review describes the importance of the airway epithelial cell in the development of allergic airway diseases, its role as the primary airway defense against exposure of the airway and lung to inflammatory stimuli and antigens and as an important player through activation of epithelial Toll-like receptors (TLRs) to provide an important link between innate immunity and allergic disease. Additionally, airway epithelial cells can act as inflammatory promoters capable of directing dendritic cells (DCs) towards a T helper 2 (Th2) response, and as active producers of several inflammatory/anti-inflammatory mediators. It is hypothesized that airway epithelial cells may play as both inflammatory initiator and immuno-pathological feedback regulation between allergic rhinitis and asthma via release of systemic inflammatory mediators. Thus, airway epithelial cells may be valuable therapeutic targets for discovery and development of new drugs and/or new therapeutic strategies to treat asthma and allergic rhinitis.

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    • "These involve other cell types like neutrophils, alveolar macrophages but also natural killer cells (Kim et al., 2010). Airway epithelial cells also contribute to asthma development , for instance as producers of inflammatory and anti-inflammatory cytokines involved in development of both allergic and non-allergic asthma (Kim et al., 2010;Wang et al., 2008). The three PPAR isotypes are expressed in many of the lung and immune cells believed to be involved in asthma development and exacerbation, including airway epithelium, smooth muscle cells, macrophages , T lymphocytes and eosinophils (Becker et al., 2006;Di Paola and Cuzzocrea, 2007). "
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    • "In the airways of asthma patients, exposure to allergens induces an increase in Th2 cell infiltration and Th2 cytokine expression [1]. Activated T cells have been implicated in asthma and physically interact with epithelial cells in the airway [2], [3]. As the first barrier to environmental pollutants and allergic stimuli, airway epithelial cells play an important role in driving the activation and differentiation of T cells in respiratory allergies [4], [5]. "
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