Table 1: Functions of intestinal innate immune cells, role in IBD, and response to IL-33 stimulation.

CellFunctionRole in IBDIL-33 effect

Goblet cellSecretion of mucin, TFF3 and RELM-β.Aberrant accumulation of mucin. Low TFF3 secretion.Mucosecretagogue activity.
MacrophagePhagocytosis.
Antigen presentation.
Intestinal antigenic tolerance.
Loss of tolerance.
Increased CD14 and NF-κB expression.
Secretion of TNF, IL-1β, CXCL1, and CCL3.
Basophil mast cellDefense against parasites.
Allergic response.
Controversial.Increased expression of surface ST2.
Th2 cytokine secretion.
Synergistically increases the IgE-mediated degranulation.
EosinophilDefense against parasites.
Allergic response.
Higher eosinophilic protein content in feces and intestinal fluid. Production of superoxide, IL-3, IL-5, IL-8, and GM-CSF.
Dendritic cellAntigen presentation.
Phagocytosis.
Macropinocytosis.
Accumulation in inflamed area.
Increased expression of TLR2, TLR4, and CD40.
Increases expression of MCH-II, CD86, and IL-6.
Th2 differentiation.