The Mucosal Barrier to Infection

Both the gastrointestinal tract (GIT) and respiratory tract (RIT) present an enormous surface area to the exterior environment. The mucosal epithelial cells (EC) of both GIT and RIT form a contiguous lining and separate multicellular animals from the exterior environment. Most human pathogens cause disease by attaching to, crossing, or disrupting mucosal surfaces. While appropriate inflammatory responses to pathogens occur, these usually follow primary mucosal tissue damage and pose inherent risks in terms of further barrier disruption. Consequently, a more fundamental primary mucosal barrier to prevent infection has evolved. To protect the epithelial cells, the mucosal surfaces are covered by a layer of a mucus comprising both secreted and cell surface mucins. Mucus and mucosal epithelial cells, together with underlying leukocyte-driven innate and adaptive immunity play a critical role to limit infection of mucosal tissues. In addition, the normal intestinal flora also joins force against incursion of foreign pathogens. Greater understanding of the mucosal barrier to infection will provide an improved basis for design of strategies to prevent and /or more effectively eliminate mucosal infections and to treat common inflammatory diseases caused by pathogens.

This Research Topic has a strong focus on interactions between the mucosal epithelial barrier and pathogens during respiratory or intestinal infections, we interested in both human and animal studies, providing an online forum for rapid dissemination of recent research and perspectives in this area.

We seek Original Research, Reviews Articles, and Brief Research Reports that cover, but are not limited to:

• The mechanisms of pathogens modulation of mucosal barrier function, regulation of host physiology and cellular function.

• The innate immune function of mucosal epithelium during infections.

• The interactions of mucosal epithelial cells and immune cell during infections.

• The crosstalk between epithelial cells and the gut microbiota during infections.

• The dynamic role of mucus and mucins during infection.

• Clinical studies on the mucosal interaction between host and microbes contributing to development in GIT and RIT inflammation.

• Research investigating interventions or solutions to eliminate pathogens, strengthen epithelial barrier function, or block pathogens-induced inflammation.