IL-8 induction in the ileum of the gnotobiotic piglets colonized with rough S. Infantis 1326/28 or S. Typhimurium 1591 was believed to be responsible for the protection against subsequent infection with virulent S. Typhimurium strains 98 [56] or LT2 [57], respectively. This evidence concerns the gene CXCL8 and infection.