CD AIEC replicate more than non-pathogenic E. coli K12 in monocyte-derived macrophages (MDMs) from people with IBD (CD, ulcerative colitis (UC)) and healthy controls [23], and their persistence within MDMs is variably linked to polymorphisms in genes associated with CD and autophagy-related 16-like 1 (ATG16L1), immunity related GTPase M (IRGM), Unc-51 like autophagy activating kinase (ULK-1), and X-box binding protein 1 (XBP-1) [24,25,26,27]. Here, IRGM is linked to inflammatory bowel disease.