It has previously been shown that intestinal microbiota promotes the accumulation of Ly6C+ monocytes within the lamina propria (LP) (Bain et al., 2014) and there is ample evidence that the microbiota is intimately involved in the development of colitis in many susceptible mouse models including mice lacking IL10 signaling (Kang et al., 2008; Sellon et al., 1998). This evidence concerns the gene IL10 and colitis.