Figure 3.

Immune cells contribute to the regulation of intestinal epithelial cell (IEC) differentiation and barrier function. For example, type 3 innate lymphoid cells (ILC3) secretion of interleukin‐22 (IL‐22) regulates IEC secretion of antimicrobial peptides (AMPs) and mucins, tight junction formation, and surface protein glycosylation, assisting in resistance to pathogenic microbes. Tolerance to food antigens is reported to involve IEC responsiveness to IL‐12; however, the subsequent IEC signalling pathways and immune cell types that mediate this response are not currently known.