1. ¹Mucosal Diseases Program, Mater Medical Research Institute and The University of Queensland, Level 3 Aubigny Place, Mater Hospitals, South Brisbane, Queensland, Australia
2. ²Centre for Animal Biotechnology, School of Veterinary Science, University of Melbourne, Melbourne, Victoria, Australia
3. ³Centre for BioAnalytical Sciences, Department of Chemistry, National University of Ireland, Galway, Ireland
4. ⁴Institute for Glycomics, Griffith University, Gold Coast, Queensland, Australia

Correspondence: MA McGuckin, (mmcguckin@mmri.mater.org.au)

Received 27 November 2007; Accepted 16 January 2008; Published online 5 March 2008.

Abstract

The mucosal tissues of the gastrointestinal, respiratory, reproductive, and urinary tracts, and the surface of the eye present an enormous surface area to the exterior environment. All of these tissues are covered with resident microbial flora, which vary considerably in composition and complexity. Mucosal tissues represent the site of infection or route of access for the majority of viruses, bacteria, yeast, protozoa, and multicellular parasites that cause human disease. Mucin glycoproteins are secreted in large quantities by mucosal epithelia, and cell surface mucins are a prominent feature of the apical glycocalyx of all mucosal epithelia. In this review, we highlight the central role played by mucins in accommodating the resident commensal flora and limiting infectious disease, interplay between underlying innate and adaptive immunity and mucins, and the strategies used by successful mucosal pathogens to subvert or avoid the mucin barrier, with a particular focus on bacteria.