Interestingly, prior to the onset of colitis that typically occurs in IL-10-deficient mice, the inner mucus layer was found to be significantly thicker but more permeable to bacteria-sized beads.62 This suggests a potential role for IL-10 might IL-10 in controlling mucus production and/or mucus layer integrity, further regulating access to the epithelium by mucus-associated bacteria. This evidence concerns the gene IL10 and colitis.