Host cell and mucosal immune system

The host cell and mucosal immune system is a specialized, integrated network of physical barriers and immune components that protect the body's internal surfaces exposed to the environment, such as the gastrointestinal, respiratory, and urogenital tracts (Mowat & Agace, 2014). It comprises epithelial cells, a protective mucus layer, and organized lymphoid structures like Mucosa-Associated Lymphoid Tissue (MALT), which house a diverse array of immune cells including T cells, B cells, and dendritic cells (Yoo & Desiderio, 2023). The primary biological role of this system is to provide a robust first line of defense against invading pathogens while simultaneously maintaining homeostatic tolerance toward harmless dietary antigens and commensal microbiota (Mestecky et al., 2015). Dysregulation of these processes is a hallmark of various diseases, including inflammatory bowel disease (IBD), asthma, and food allergies. While the system itself is not a single molecular target, many pharmacological agents and vaccines are designed to interact with its specific components—such as targeting alpha-4-beta-7 integrins with Vedolizumab to prevent lymphocyte homing to the gut—to treat chronic inflammation or confer protective immunity (Mowat & Agace, 2014).

Other names

Mucosal immune systemMucosa-associated lymphoid tissueMALTMucosal barrierGastrointestinal immune system

Therapeutic intervention typically involves the modulation of lymphocyte trafficking to mucosal sites, neutralization of pro-inflammatory cytokines (e.g., TNF-alpha), or the induction of local secretory IgA antibodies to prevent pathogen attachment (Mowat & Agace, 2014; Mestecky et al., 2015).