Inflammation of any segment of the ILEUM and the ILEOCECAL VALVE.

A chronic transmural inflammation that may involve any part of the DIGESTIVE TRACT from MOUTH to ANUS, mostly found in the ILEUM, the CECUM, and the COLON. In Crohn disease, the inflammation, extending through the intestinal wall from the MUCOSA to the serosa, is characteristically asymmetric and segmental. Epithelioid GRANULOMAS may be seen in some patients.

The distal and narrowest portion of the SMALL INTESTINE, between the JEJUNUM and the ILEOCECAL VALVE of the LARGE INTESTINE.

A reagent that is used to neutralize peptide terminal amino groups.

INFLAMMATION of LYMPH NODES in the MESENTERY.

Differentiated epithelial cells of the INTESTINAL MUCOSA, found in the basal part of the intestinal crypts of Lieberkuhn. Paneth cells secrete GROWTH FACTORS, digestive enzymes such as LYSOZYME and antimicrobial peptides such as cryptdins (ALPHA-DEFENSINS) into the crypt lumen.