Mucin-associated surface proteins

Af-terminal Von Willebrand factor D domains that are cysteine rich and facilitate intermolec-ular covalent cross-linking via disulfide bond formation. Apomucins are glycosylated as they traverse the Golgi apparatus and are localized exclusively at the apical cell surface by virtue of their transmembrane domain. Membrane associated mucins can also be secreted as a result of proteolytic processing of the cell surface protein or RNA splice variation that encodes the secreted protein. 

However, in spite of these similarities, the adsorbed amounts and the structure of the adsorbed mucin and collagen layers on the surfaces studied are entirely different. The behavior of these proteins is analyzed here on the hydrophobic polyethylene surface (water contact angle 0 20 95°), on the surface modified polyethy-lenes oxidized polyethylene (0h q 74°) and poly(maleic acid) grafted polyethylene ( Ho0 74°) a d on the hydrophilic mica surface ( H2 0 0°) Acidic pH = 2.75 (for collagen) and slightly alkaline pH = 7.2 (for mucin) were chosen in order to minimize the association of these proteins in solution and to make possible the analysis of their adsorbabilities in comparable conditions. 

A number of recent reports have identified KS associated with epithelial surfaces. In adult tissues, keratinocytes, uterine endometrial cells, corneal endothelium, sebaceous gland, salivary gland, and sweat gland epithelia exhibit KS immunoreactivity [30-32]. Additionally KS is expressed by epithelial-derived carcinoma cells [33, 34]. Recently the endometrial protein MUCl was shown to bear KS chains [35]. This glycoprotein is a common component of the mucin layer associated with apical surfaces of secretory epithelia and could be responsible for the KS observed in many of these glandular surfaces. Another cell-surface molecule CD44 has been... 

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