Secretion of nitric oxide, IL-6, MCP-1, IFN-γ and TNF-α in ex vivo colon biopsies were significantly increased at day 12 following infection with C. jejuni ATCC 43431 or B2 versus naïve animals with supra-physiological intestinal E. coli loads (Fig. 9). The gene discussed is TNF; the disease is infection.