CASP3 and ulcer disease: Given that apoptosis is a commonly used diagnostic marker in the histopathological evaluation and grading of intestinal disease [21] and a key feature of C. jejuni induced ulcerative enterocolitis in gnotobiotic IL-10−/− mice [18], we quantitatively assessed caspase-3+ cells within the colonic mucosa following infection with the respective C. jejuni strains.