Presence of a functional CDT in C. jejuni enhances gastritis, gastric epithelial hypersplasia and mild dysplasia, and proximal duodenitis in mice deficient for the NFκB subunits (p50−/− p65+/−, referred to as 3X mice) at 4 months post-infection (p.i.)compared to mice colonized with an isogenic cdtB mutant strain (in spite of a similar level of colonization). This evidence concerns the gene NFKB1 and duodenitis.