ACE2 and inflammatory bowel disease: In IBD, ACE2 levels vary by disease (UC ∼unchanged; CD lower); activity (higher in active vs inactive UC) and region (ileum vs colon), whereas differential expression may also influence responsiveness to IBD therapies.35, 36, 37, 38, 39 In mucosal biopsies, active disease increased ACE2 in UC—which may increase virus entry—whereas patients with CD had lower ACE2, which may increase pathogenic roles of its substrate, AngII.35