Epithelial Cells Orchestrate the Functions of Dendritic Cells in Intestinal Homeostasis

The gastrointestinal tract represents the largest mucosal membrane surface and is the one
of the most complex human organs. The intestinal barrier dysfunction contributes to systemic
immune activation. The mucosal immune system has extremely arduous tasks to resist invaders
and promote tolerance of food antigens and the microbiota. The intestinal mucosal immune
system fulfills these tasks through complex interactions between immune cells and the local
microenvironment in intestine. Intestinal Epithelial Cells (IECs) play important roles in these
complex interactions. IECs not only constitute the first barrier of the intestine but also are crucial
for integrating external and internal signals and for coordinating the ensuing immune response.
Dendritic Cells (DCs) play key roles in shaping the intestinal immune response by their ability to
coordinate protective immunity and immune tolerance in the host. DCs are pivotal actors in the
connection between innate and adaptive immune responses. The IECs coordinate with the DCs in
immune recognition, tolerance and host defense mechanisms. In this review, we will summarize
how IECs orchestrate intestinal DCs in intestinal homeostasis and diseases.