Mucinous glycoprotein

Reddy, G. P. and Bush, C. A., High-performance anion exchange chromatography of neutral milk oligosaccharides and oligosaccharide alditols derived from mucin glycoprotein, Anal. Biochem., 198, 278, 1991. 

Kindon, H., Pothoulakis, C., Thim, L., Lynch-Devaney, K. and Podolsky, D.K. (1995) Trefoil peptide protection of intestinal epithelial barrier function cooperative interaction with mucin glycoprotein. Gastroenterobgy 109, 516-523. 

FIG. 1. Three stages in the interaction between a mucoadhesive polymer and mucin glycoprotein according to the interpenetration theory. 

Table 1 The Eight Different Core Structures of Mucin Glycoproteins 23 182183-264-265 ...

Scheme 12 Important Mucin Glycoprotein Glycan Structures...

The viscous mucus layer provides a physical protective barrier for the mucosa trapping, binding, and clearing inspired particles. Approximately 1.5-2 L of mucus is secreted daily and the resultant gel layer varies between 5 and 10 pm in thickness. Mucus is composed of 95% water plus mucin glycoproteins (0.5%-5%), lipids in low proportions, mineral salts (1%), and... 

Two steps have been described in adhesive bond formation (1) intimate contact of the mucoadhesive agent and of mucus or mucosa consequent to wetting and (2) formation of physical or chemical bonds between the biological substrate and the mucoadhesive agent, preceded, in the case of polymeric materials, by interpenetration and diffusion between the bioadhesive and the mucin glycoprotein. 

FIGURE 22.2 Schematic representation of interpenetration of polymer chains and mucin glycoproteins. 

K. A. Thomsson, N. G. Karlsson, and G. C. Hansson, Liquid chromatography-electrospray mass spectrometry as a tool for the analysis of sulfated oligosaccharides from mucin glycoproteins, J. Chromatogr. A, 854 (1999) 131-139. 

Rose M.C., Voter W.A., Sage H., Brown C.F. and Kaufman, B. (1984). Effects of deglyco-sylation on the architecture of ovine submaxillary mucin glycoprotein. J Biol Chem. 259, 3167-3172... 

Another common feature of tumors is the over-production of certain glycoproteins and gly-colipids. In particular, epithelial tumors often overproduce mucin glycoproteins, which are... 

Among the fungal and protozoal lectins only a few have been studied in detail. One of these is the galactose-specific lectin of the protozoa Entamoeba histolytica. It mediates adhesion of the parasite to human colonic mucin glycoproteins and has a central role in the contact-dependent cytolysis or histolysis for which the parasite is named. A sialic-acid-speeific lectin has been isolated from merozoites of the human malarial parasite, Plasmodium falciparum. An unusual lectin is that of the protozoan Giardia lamblia, specific for mannose-6-phosphate, which is activated by trypsinization. 

The viscous and gel-forming properties of mucus secretions are derived from mucin glycoprotein constituents (5%) they also contains protein, lipid and nucleic acid, much of it derived from dislodged epithelial cells and bacteria [199]. These constituents have been shown to enhance the viscous properties of mucins in vitro [200, 201], and such interactions may be significant towards determining mucus gel properties in vivo. 

Figure 3 (a) Polyplexes are formed by electrostatic interaction between polycations and nucleic acids. Schematic interaction of positive polyplexes with the negatively charged cell membrane. Adapted from Pack, D. W. Hoffman, A. S. Pun, S. Stayton, P. S. Nat Rev. Drug Discov. 2005,4,581, copyright 2005 (b) Hypothetical scheme about the formation of covalent bonds between thiolated polymers and mucin glycoproteins. Adapted from Leitner, V. M. Walker, G. F. Bemkop-Schnurch, A. Eur. J. Pharm. Biopharm. 2003,56,207. ... 

Figure 4.25 Schematic representation of mucoadhesive interactions of thiomers with mucin glycoproteins.

---