Airway secretory cells

One explanation for the mechanism of efficacy would be macrolides direct effects on airway secretory cells. Indeed, Goswami et al. [11] first studied nasal mucous glycoconjugate secretion from healthy nonsmoking adults before and after... 

Mucociliary Clearance Mucociliary clearance operates by the coordinated movements of cilia, which sweep mucus out of the lungs towards the pharynx where it is swallowed. There is an inverse relationship between mucus velocity and airway generation, which relates to the lower percentage of ciliated cells, shorter cilia, lower ciliary beat frequency and lower number of secretory cells in the peripheral airways [121]. The reported tracheal mucociliary clearance... 

The ciliated cells are most vulnerable to damage. The most frequent degenerative changes in these cells are loss of cilia, necrosis, and sloughing of cells into the airway lumen. Necrosis and desquamation of nonciliated and secretory cells are less frequently observed. 

The nasal mucosa is highly vascular superficial and deep layers of arterioles supply the lamina propria and between the venules and capillaries there are numerous sinuses or venous lakes which are linked to erectile tissue, particularly in the middle and inferior turbinates, which enable the airways to widen or narrow. This autonomically controlled vasculature of the nasal tissue, in combination with its rich supply of secretory cells, is of importance in the modification of inspired air. 

Abbinante-Nissen JM, Simpson LG, Leikauf GD Corticosteroids increase secretory leukopro-tease inhibitor transcript levels in airway epithelial cells. Am J Physiol 1995 265 L286—L292. 

Merigo F, Benati D, Di Chio M, Osculati F, Sbarbati A. Secretory cells of the airway express molecules of the chemoreceptive cascade. Cell Tissue Res. 2007 327 231-247. 

Christensen, T.G., Breuer, R., Lucey, E.C., Stone, P.J. and Snider, G.L. (1989). Regional difference in airway epithelial response to neutrophil elastase tracheal secretory cells discharge and recover in hamsters that develop bronchial secretory cell metaplasia. Exp. Lung Res. 15, 943-959. 

Jeffery PK, Li D. Airway mucosa secretory cells, mucus and mucin genes. EurRespir J 10(7) 1655-1662, 1997. 

Merigo F, Benati D, Di Chio M, Osculati F, Sbarbati A (2007) Secretory cells of the airway express molecules of the chemoreceptive cascade. Cell Tissue Res 327 231-247 Miller IJ Jr (ed) (1995) Anatomy of the peripheral taste system. Dekker, New York Miller IJ Jr, Reedy FE Jr (1990) Variations in human taste bud density and taste intensity perception. Physiol Behav 47 1213-1219... 

Three of the cell types in the epithelium have secretory functions. These cells are the mucous (goblet) cells, serous cells, and Clara cells. These cells contribute to the secretion of airway mucus, a complex mixture of water, glycoproteins, immunoglobulins, lipids, and salts. The secretion of mucus is a defense function that contributes to the removal of foreign objects from lung airways via the mucociliary transport process, as described in later sections of this chapter. Excess mucus secretion can be detrimental, however, since it can obstruct the movement of air through the airways and is a component of certain pulmonary diseases such as asthma, emphysema, chronic bronchitis, and cystic fibrosis. A hypertrophy of secretory cells in the epithelial layer of the airways is often characteristic of these diseases. 

Illustrated in Figure 3 is a likely over-all mechanistic role of theophylline in asthma. Extrinsic or immediate hypersensitivity-type asthma begins with an antigen -antibody complex at mast cells and results in the release of chemical mediators which affect cells in airways. Smooth muscle cells contract, capillaries leak, and secretory cells hypersecrete to give a triad of bronchospasm, edema and Increased mucous, respectively. Shown is the two-enzyme... 

Leidal KG, Munson KL, Denning GM. Small molecular weight secretory factors from Pseudomonas aeruginosa have opposite effects on IL-8 and RANTES expression by human airway epithelial cells. Am J Respir Cell Mol Biol 2001 25 186. 

In response to injury caused by various pollutants, toxicants, and carcinogens, proximal and distal airway epithelial cells lose their normal secretory functions and express squamous and keratinis-ing properties (Plopper 1997). 

Clearance of foreign materials (particles) from the lung and airways depends on the function of macrophages, ciliated cells and secretory cells, and on the physical and chemical properties of the alveolar cells. All these are affected by ozone exposure. Single acute exposure of animals and humans to ozone concentrations less than 0.6 ppm have been shown to accelerate clearance of particles from the tracheobronchial tree whereas acute exposures to ozone levels greater than 0.6 ppm caused a delay in particles clearance [79, 261]. Repeated exposures (2 h daily for 14 days) to 0.1 ppm ozone gave rise to acceleration in alveolar clearance of latex particles but had no effect on tracheobronchial clearance. These results, related to morphological studies, are consistent with certain adaptation [278-283]. 

Halbert CL, Aitken ML, Miller AD. Retroviral vectors efficiently transduce basal and secretory airway epithelial cells in vitro resulting in persistent gene expression in organotypic culture. Hum Gene Ther 1996 7 1871-1881. 

It appears that a substantial part of the airway surfactant is derived from the alveolar region, but there is also evidence for local production of surfactant. Widdicombe (41) reviewed the possible sources and potential biological role of tracheal surfactants. He concluded that the trachea contains a complex mixture of lipids, including surface-active phospholipids not characteristic of alveolar surfactant. Experiments (60) have shown that nonciliated cells of the bronchioles produce surface-active material and that these cells are involved in ion and water transport. Other studies (43) demonstrated phospholipids in secretory cells of airway submucosal glands, suggeshng local produchon of phospholipids in the... 

If local production of surfactant components occurs in the airways, which cells are involved One candidate is the Clara cell. Clara cells are nonciliated, nonmucous secretory cells, located in the surface epithelium of the airways (48,56). They are usually found in the bronchioles (56). Oeeasionally, cells resembling Clara cells morphologically are found in larger airways, including the trachea. There is variability in the cellular and organellar distribution among dif-... 

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