About this Research Topic
The epithelial cells at the mucosal surface form a selectively permeable, immunologically tolerant but alert barrier between the sterile inside and microbe-laden outside. Besides maintaining homeostasis, as the primary entry site for food-borne or air-borne pathogens, mucosal epithelial cells develop a series of mechanisms to combat infections: generating mucus layer to physically stop pathogen evading; upregulation of pattern recognition receptors to sense infectious agents; activation of NF-B inflammatory signaling and secreting cytokines/chemokines to recruit downstream immune cells; secretion of Type I interferons in response to viral infections and increasing MHC class molecules expression for antigen presentation to underlying innate immune cells.
Mucosal epithelial cells function as the sentinel cells to detect the presence of foreign antigen and contribute to immune tolerance at the mucosal surface. The function of mucosal epithelial cells and their ability to initiate the early inflammatory signal upon infection have not been extensively explored. Mucosal epithelial cells interact closely with lamina propria macrophages, dendritic cells, and stromal cells. Notably, these interactions are two-way interactions with the epithelial cells instructing genuine immune cells and vice versa to prime a tolerogenic immune response. However, unlike professional antigen-presenting cells, epithelial cells are unable to present antigens to immune cells directly, mechanisms used by epithelial cells to instruct downstream immune responses during early infections are poorly understood. In addition, we are particularly interested in how the tolerogenic immune balance between mucosal epithelial cells and commensal flora are disrupted in the presence of dangerous pathogens.
This Research Topic will give a comprehensive overview of mucosal epithelial cell and innate immune cell interactions during infections, highlighting the role of epithelial cells in instructing and amplifying inflammatory immune responses against infections.
In this research issue, we welcome both human and animal studies that focus on interactions between the mucosal epithelial barrier and pathogens during respiratory or intestinal infections.
We seek Original Research Articles, Reviews, Brief Research Reports, and Mini-Reviews that cover, but are not limited to, the following topics:
• The innate immune function of mucosal epithelium during infections.
• Mucosal epithelial cell antigen processing and presentation pathways during infections.
• Mucosal epithelial cells and innate immune cell interactions in early infections.
• Infectious disease animal models that highlight the role of mucosal epithelial cells in infections.
• Role of the mucosal epithelium in pathogen clearance.
Keywords: Infections, mucosal Epithelia Cells, Antigen Sensing and Presentation, Innate Immune Cells, Cytokines, pathogens, host defense
Important Note: All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.