To characterize the adventitial leukocyte and macrophage populations in Control and IBD arteries with and without macrophage depletion, we conducted two sets of confocal immunolabeling studies counting the number of cell labeled for: CD45 (all leukocytes), MCHII (antigen presenting cells), CD68 (M1-like macrophages), and CD163 (M2-like macrophages). This evidence concerns the gene CD163 and inflammatory bowel disease.