Partial to complete abrogation of the subepithelial macrophage barrier against the gut microbiota in patients with ulcerative colitis and Crohn's colitis.

The finding that the SLP macrophage barrier was fragmented to totally abrogated in UCre and RCC patients suggests a longlasting defect in the SLP CD68+ macrophage barrier in these patients. The lack of ongoing inflammation in colonic biopsies should rule out the participation of bone marrow-derived IEMs in the abrogation of the SLP macrophage barrier reported here.