Increased epithelial uptake of protein antigens in the ileum of Crohn's disease mediated by tumour necrosis factor

Background and aims: The exact nature of the epithelial barrier defect in Crohn’s disease remains to be elucidated. Previously we showed increased permeability to proteins in ileal Crohn’s disease. Our aims were to study if this barrier defect (a) involves endocytotic uptake of antigens and (b) is related to low grade inflammation not detectable by histology. Methods: Macroscopically normal segments of distal ileum of Crohn’s disease patients (n...