The Epithelial Mucins

Karsten, U., Serttas, N., Paulsen, H., Danielczyk, A., and Goletz, S. (2004) Binding patterns of DTR-specific antibodies reveal a glycosylation-conditioned tumor-specific epitope of the epithelial mucin (MUC1). Glycobiology 14(8), 681-692. 

Hens, J.R., Rogers, G.W., Huott, M.L., Patton, S. 1995. Association of the epithelial mucin, PAS-1, with yield, health, and reproductive traits in Holstein dairy cows. J. Dairy Sci. 78, 2473-2480. 

Patton, S., Gendler, S.J., Spicer, A.P. 1995. The epithelial mucin, MUC1, of milk, mammary gland, and other tissues. Biochim. Biophys. Acta 1241, 407-424. 

Brocke C, Kunz H (2004) Synthetic tumor-associated glycopeptide antigens from the tandem repeat sequence of the epithelial mucin MUC4. Synthesis 525-542... 

Histochemical demonstration of most of the O-acetylated sialic acids is possible because substituents on the side chain of Neu hinder periodate oxidation of this part of the molecule to an extent dependent on the number and position of the O-acetyl groups already mentioned. Correspondingly, removal of these ester groups by alkaline treatment (0.5% KOH in 70% ethanol91) may increase the staining reaction of a sialic acid. For example, the presence of O-acylated sialic acids has been demonstrated in colonic, epithelial mucin of man and various mammals (summarized in Ref. 91), in healthy and diseased, human small-intestine,188-190 in bovine submandibular gland,182 in mouse and rat erythrocyte-membranes,191 and in human lymphocytes.192... 

A deep layer rich in mucus and the origin of which is to be found in the conjunctival calyciform cells. This mucus is in relation with the apical epithelial cells via the glycocalyx. This interface between the lacrymal secretion and the epithelium influences the quality of the corneal surface. Indeed, the stability of the lacrymal secretion and the epithelial absorption of its metabolites both depend on the mucin and the apical expansions of the epithelial cells [2]. 

Argueso P, Gipson IK (2001) Epithelial mucins of the ocular surface structure, biosynthesis and function. Exp Eye Res 73(3) 281—289... 

Q9 The stomach secretes a very acid gastric juice with a pH of 1.5-2. The mucosa is normally protected from acid by a number of mechanisms. Mucus is produced by the large number of mucous cells in the body and fundus. It contains glycoproteins called mucins, and the mucus produced forms a kind of gel which coats the mucosal surface. In addition these cells secrete HCO3-, which is trapped in the mucus and increases the local pH to form a less acidic environment at the surface of the epithelial cells. 

A significant positive correlation has been observed between the levels of inflammatory cytokines in the conjunctival epithelium and the severity of ocular irritation symptoms and corneal fluorescein staining. The inflammatory cytokines and other inflammatory mediators also correlate positively to severity of conjimctival squamous metaplasia in Sjogren patients. These proin-flammatory cytokines also have been implicated in regulation of epithelial mucin expression, with several studies suggesting inflammation is central to the pathogenesis of meibomian gland dysfunction as well. 

P2Y2 receptors are present in the epithelial cells of the ocular surface and stimulation of them by ATP increases mucin-like glycoprotein secretions in conjunctival... 

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