IRGM and inflammatory bowel disease: Because previous work demonstrated that environmental factors, including microbial influences, can affect the penetrance and severity of intestinal inflammation in murine models of inflammatory bowel disease (IBD) (Foltz et al., 1998; Maggio-Price et al., 2006; Ward et al., 1996; Peloquin and Nguyen, 2013; Cadwell et al., 2010), we sought to determine whether environmental conditions impact the inflammatory and PC phenotypes in Irgm1-deficient mice.