Epithelial-neuronal-immune cell interactions: Implications for immunity, inflammation, and tissue homeostasis at mucosal sites

Abstract

The epithelial lining of the respiratory tract and intestine provides a critical physical barrier to protect host tissues against environmental insults including dietary antigens, allergens, chemicals, and microorganisms. In addition, specialized epithelial cells directly communicate with hematopoietic and neuronal cells. These epithelial-immune and epithelial-neuronal interactions control host immune responses and have important implications for inflammatory conditions associated with defects in the epithelial barrier, including asthma, allergy, and inflammatory bowel diseases (IBD). In this review, we discuss emerging research that identifies the mechanisms and impact of epithelial-immune and epithelial-neuronal crosstalk in regulating immunity, inflammation, and tissue homeostasis at mucosal barrier surfaces. Understanding the regulation and impact of these pathways could provide new therapeutic targets for inflammatory diseases at mucosal sites.