FOXP3 and inflammatory bowel disease: FoxP3+ Tregs spread and collect on the inflamed mucosa of the inflammatory bowel disease (IBD) patients.5, 6 T helper cells produce IL‐17 (Th17 cells) for mucosal homoeostasis and are implicated in the pathogenesis of CD.7, 8 Th17 cells would protect the host from infection at mucosal surfaces, whereas Tregs control immune responses and inflammation caused by the microflora.9, 10