Surprisingly, IL‐4 and IL‐13 producing Th2 cells were significantly reduced in both UC and CD, suggesting that Th2 cells may not be the main source of these cytokines in IBD, reminiscent of a predominant production of IL‐4 and IL‐13 by NKT cells in allergen‐induced airway hyperreactivity (Akbari et al, 2003). This evidence concerns the gene IL13 and inflammatory bowel disease.