Mucouse goblet

Perez-Vilar J., Randell S.H. and Boucher R.C. (2004). C-Mannosylation of MUC5AC and MUC5B Cys subdomains. Glycobiology 4, 325-337 Perez-Vilar J., Olsen J.C., Chua M. and Boucher R.C. (2005a). pH-dependent intraluminal organization of mucin granules in live human mucous/goblet cells. J. Biol. Chem. 280, 16868-16881... 

Perez-Vilar J., Mabolo R. McVaugh C.T., Bertozzi C.R. and Boucher R.C. (2006). Mucin granule intraluminal organization in living mucous/goblet cells. Roles of protein post-translational modifications and secretion. J Biol Chem. 281, 4844-4855 Perez-Vilar J. (2007). Mucin granule intraluminal organization. Am J Respir Cell Mol Biol,... 

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. 

More serious respiratory effects were seen upon histological examination of the respiratory tract at the end of this study. Gross lung changes observed in the rabbits included collapsed dark red areas, hyperemia, and the accumulation of mucous material. The trachea and the major bronchi showed areas of epithelial desquamation, relative atrophy, flattening of the mucosa, and foci of goblet cell metaplasia. 

Enlarged mucous glands and an increased number of goblet cells produce an excessive amoimt of mucus... 

Fig. 1. Small intestine formaldehyde-fixed, paraffin-embedded. Section was stained with Concanavilin A conjngated to 5-nm colloidal gold. The gold was then silver-enhanced. Staining of mucous on the cell snrface and in goblet cells is seen.

The pharynx, larynx, trachea and bronchi are lined with pseudostratified, ciliated columnar epithelium that contain at least eight cell types, including mucous secretory goblet and Clara cells, which produce a protective mucus layer of 5-10 jum thickness (see Table 9.2). Subepithelial secretory glands, present in the bronchial submucosa, also contribute to the mucus blanket [9]. Through coordinated ciliary movement a propulsive wave is created, which continuously moves the mucus layer up towards the larynx. Consequently, the mucosal surface of trachea and bronchi is constantly swept to remove inhaled materials. As the bronchi divide into bronchioli, the ciliated columnar respiratory epithelium is much thinner and changes to a simpler non-ciliated cuboidal epithelium. The epithelium in the terminal and respiratory bronchioles consists of ciliated, cuboidal cells and a small number of Clara cells. However, Clara cells become the most predominant type in the most distal part of the respiratory bronchioles [10]. 

Conducting airways Trachea 0 20-18 Pseudostrati fled cell Ciliated cell Columnar cell Goblet cell Serous cell Mucous cell 20-40... 

FIGURE 2 Cell types of nasal epithelium showing ciliated cell (A), nonciliated cell (B), goblet cell (C), gel mucous layer (D), sol layer (E), basal cell (F), and basement membrane (G). (Reproduced from ref. 5 with permission of Pharmaceutical Press.)... 

Epidermal keratinization and mucous membrane squamous metaplasia respond to both oral and topical vitamin A therapy. Vitamin A exists in three forms retinol, retinal, and retinoic acid.VitaminA increases the mucous production of goblet cells and perhaps the aqueous and lipid components of the tears as well. Tretinoin is a normal metabolite and the carboxylic form of retinol. Retinol is present in tears and the lacrimal gland appears to be its major provider. Retinoic acid has been shown to be effective in ocular surfece disorders such as squamous metaplasia by reversing the corneal and conjunctival keratinization and improving epithelium wound healing rate. 

Fig. 1 (A) Cross-sectional structure of the human nose. NV = nasal vestibule AT = atrium NP = nasopharynx IT = interior turbinate and orifice of the nasolacrimal duct MT = middle turbinate and orifices of frontal sinus, anterior ethmoidal sinuses, and maxillary sinus ST = superior turbinate and orifices of posterior ethmoidal sinuses hatched area, olfactory region. (B) Four major cell types in the nasal epithelium (a) non-ciliated columnar cell with microvilli (b) goblet cell with mucous granules and Golgi apparatus (c) basal cell and (d) ciliated columnar cell with many mitochondria in the apical part. (Reprinted from Ref. with permission from Elsevier.)...

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