CLEC7A and fungal infectious disease: Lactobacillus murinus proliferates in Clec7a–/– mice, because levels of the antimicrobial protein calprotectin S100A8, which is induced downstream of DECTIN‐1 signaling through induction of IL‐17F and can inhibit Lactobacillus growth, is reduced in these mutant mice.22, 23 Therefore, DECTIN‐1 acts as a double‐edged sword in the regulation of colitis development; it is necessary for protection against fungal infection, but excess DECTIN‐1 signaling suppresses Treg cell differentiation and induces inflammation.