Nasopharyngeal epithelial cells

The critical first step in the acquisition of acute bacterial meningitis is nasopharyngeal colonization of the host by the bacterial pathogen. The bacteria first attach themselves to nasopharyngeal epithelial cells and are then phagocytized into the host s bloodstream. 

Zhang JR, Mostov KE, Lamm ME, et al.The polymeric immunoglobulin receptor translocates pneumococci across human nasopharyngeal epithelial cells. Cell 2000 102(6) 827-37. 

Tonnaer EL, Hafmans TG, Van Kuppevelt TH, Sanders EA, Verweij PE, Curfs JH. Involvement of glycosaminoglycans in the attachment of pneumococci to nasopharyngeal epithelial cells. Microbes Infect 2006 8 316-322. 

Children also frequently suffer from influenza infections, which have high rates of morbidity primarily because of the associated complications (5). Perhaps a way to reduce the duration of these viral illnesses and their spread is to reduce the abundant nasopharyngeal secretions caused by the production of the cytokine interleukin-6 (IL-6) by infected epithelial cells. Reducing these secretions may also reduce coughing, sneezing, and the spread of the virus by hands. The n-3 polyunsaturated fatty acids may reduce lL-6 production by nasopharyngeal epithelial cells as described below. 

Although infection by EBV can cause infectious mononucleosis and can lead to EBV-associated cancers, notably Burkitt s lymphoma and nasopharyngeal carcinoma in restricted geographic regions, most humans are infected by the virus without symptoms. Latent infection is believed to involve both epithelial cells of the oropharynx and B lymphocytes, and, as with other herpes viruses, is presumed to last lifelong (see ref. 2 for a review). 

From a cellular viewpoint, the respiratory tract is extraordirrarily complex, consisting of more than 40 different individual cell types. The airways of the nasopharyngeal and tracheobronchial compartments are lined by epithelial cells. The most anterior portion is lined by stratified squamous epithelium that in a short distance transitions to respiratory epithelium, with numerous ciliated cells and occasional goblet cells that serve as a source of mucus. 

The ciliated epithelial cells extend down the respiratory tract to the respiratory bronchioles. The cilia provide locomotion for the overlying mucous blanket, propelling mucus and associated debris forward in the most anterior portion of the nares or propelling it to the oral cavity in the most posterior portion of the nasopharyngeal compartment. In the tracheobronchial compartment, mucus and associated material are moved upward to the oral cavity. 

Lindstrom Carlsson, 1993 Rotmensch et ah, 1994). Spheroid-like hollow bodies with a multicellular epithelial morphology have also been utihzed as a model of pathogenesis of infection as a result of Neisseria infection. Numerous cell-cell contacts representative of cells in vivo have been demonstrated in spheroids from nasopharyngeal cells, e.g. junctional complexes, desmosomes, specific orientation of the cytoskeleton and cellular organelles (Boxberger et aL, 1993). 

Stratified squamous epithelial tissue is a frequently found epithelium in the human body (nasopharyngeal and oral cavities, esophagus, urethra, vagina, cervix, and others). It is a multilayered structure consisting of a layer of actively dividing basal cells anchored to the basement membrane, beneath which one finds connective tissue (stroma). The daughter cells created by the division of the basal cells form the parabasal layer and mature and migrate to the surface layer. 

Rat 6h/day x 3 days 6h/day x 5 days 6h/day x 5 days 9.1 1.02 (TWA) 0.1, 0.5,1.0 2.5 BW 1 marked nasal epithelial degeneration, cell exfoliation, ulceration, and necrosis neutrophil infiltration of epithelium and squamous metaplasia after 5 days milder lesions in pharynx, trachea, and lungs. Nasal inflammation and hyperplasia in squamous and respiratory epithelium (concentration-dependent) but not OE extended to the nasopharyngeal duct at 2.5 ppm. Jiang et al. (1983) George et al. (2010) Jarabek et al. (2010)... 

Nasopharyngeal carcinoma (NPC) and Burkitt lymphoma are strongly associated with Epstein-Barr virus (EBV) infection (lARC 1997) and account for approximately 1% of world cancer cases (lARC 2003a). NPC is an epithelial tumor with a high prevalence in southern China, where the incidence rate is about 25-50 per 100,000 people-year and 100-fold higher than that in the Western world (Jeannel et al. 1999 McDermott et al. 2001). Latent EBV infection is detected in cancer cells of virtually all cases of undifferentiated NPC in endemic regions (lARC 2003 a Tsai... 

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