Infection mucins

Mucins are also thought to act in cooperation with trefoil proteins in the protection and repair of the epithelium (Kindon et al., 1995). Trefoil factors are expressed along the GI tract and increased levels are noted near sites of inflammation and ulcerative lesions (Babyatsky et al., 1996). Furthermore, it has been demonstrated that mouse intestinal trefoil factor may play a role in the alteration of the physicochemical nature of GC mucins during N. brasiliensis infection (Tomita et al., 1995). Perhaps in GI nematode parasite infection mucins are not aiding in the host s protective expulsion of the parasite, but rather are functioning in the repair of the damaged intestinal epithelium. 

Jany, B., Gallup, M., Tsuda, T. and Basbaum, C. (1991). Mucin gene expression in rat airways following infection and irritation. Biochem. Biophys. Res. Commun. 181, 1-8. 

Gems, D.H. and Maizels, R.M. (1996) An abundantly expressed mucin-like protein from Toxocara canis infective larvae the precursor of the larval surface coat glycoproteins. Proceedings of the National Academy of Sciences USA 93,1665-1670. 

Ishikawa, N., Horii, Y. and Nawa, Y. (1993) Immune mediated alteration of the terminal sugars of goblet cell mucins in the small intestine of Nippostrongylus brasiliensis infected rats. Immunology 78, 303-307. 

Increased numbers of goblet cells (GCs) and qualitative changes in mucus secretions are coincident with infection with a number of nematode parasites and it has been proposed that mucin proteins mediate this response by enveloping the parasites and/or interrupting attachment (Nawa et al., 1994). However, the role of GCs and mucus in the generation of a protective response versus its role in resolving intestinal inflammation following infection with GI nematode parasites remains unresolved. 

Muc2 and Muc3, and mucin mRNA are coordinately upregulated in response to T. spiralis infection and may form the basis of an innate mucosal response independent of specific IFN-y, TNF and IL-4 cytokines. Importandy, this study also demonstrated that goblet cell hyperplasia and upregulated mucin secretion are not essential components of the protective immune response to GI helminths. 

Shekels, L., Anway, R.E., Lin, J., Kennedy, M.W., Garside, P., Lawrence, C.E. and Ho, S.B. (2000) Coordinated Muc2 and Muc3 mucin gene expression in Trichinella spiralis infection in wild-type and cytokine deficient mice. Infection and Immunity (submitted). 

Mack, D. R., and Sherman, P. M. (1991). Mucin isolated from rabbit colon inhibits in vitro binding of Escherichia coli RDEC-1. Infect. Immun. 59, 1015-1023. 

Mantle, M., and Husar, S. D. (1994). Binding of Yersinia enterocolitica to purified, native small intestinal mucins from rabbits and humans involves interactions with the mucin carbohydrate moiety. Infect. Immun. 62,1219-1227. 

Namavar, F., Sparrius, M., Veerman, E. C., Appelmelk, B. J., and Vandenbroucke-Grauls, C. M. (1998). Neutrophil-activating protein mediates adhesion of Helicobacter pylori to sulfated carbohydrates on high-molecular-weight salivary mucin. Infect. Immun. 66, 444- 7. 

Sylvester, F., Philpott, D., Gold, B., Lastovica, A., and Forstner, J. (1996). Adherence to lipids and intestinal mucin by a recently recognized human pathogen, Campylobacter upsaliensis. Infect. Immun. 64,4060 066. 

Schroten, H., Hanisch, F. G., Plogmann, R., Hacker, J., Uhlenbruck, G., Nobis-Bosch, R., and Wahn, V. (1992). Inhibition of adhesion of S-fimbriated Escherichia coli to buccal epithelial cells by human milk fat globule membrane components A novel aspect of the protective function of mucins in the nonimmunoglobulin fraction. Infect. Immun. 60,2893-2899. 

Burnett FM. Mucins and mucoids in relation to influenza virus action. IV. Inhibition by purified mucoid of infection and haemagglutinin with the virus strain WSE. Aust J Exp Biol Med Sci 1947 26 381-387. 

According to some authors, the success in the establishment of infection by the oral route is associated with the expression of gp82, a surface glycoprotein, which binds to mucin and gastric epithelial cells. This molecule promotes the entrance of trypomastigotes through a cascade reaction that culminates with the mobilization of intracellular calcium (Ruiz et al., 1998). 

Lin J., Haruta A., Kawano H., Ho S.B., Adams G.L., Juhn S.K. and Kim Y. (2000) Induction of mucin gene expression in middle ear of rats by tumor necrosis factor-alpha potential cause for mucoid otitis media. J Infect Dis 182, 882-887 Madsen F., Eberth K. and Smart J.D. (1998) A Rheological examination of the Mucoadhe-sive/Mucus Interaction the Effect of Mucoadhesive Type and Concetration. J. Control Release 50, 167-178... 

It is widely held that mucus should possess specific rheological properties for clearance from the airway to occur. Any alteration in mucus rheology that compromises clearance can predispose the individual to airway disease and infection. Some agents capable of altering mucus rheology are listed in Table 9.2. In addition, the state of mucus hydration (or mucin concentration) will affect the properties of the gel. In... 

Infection given intraperitoneally with 45 to 300 LDjo suspended in 5% hog gastric mucin. Therapy by the subcutaneous route as two doses 0 and 6 hr after infection. 

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