Secreted effector proteins of Salmonella enterica serotype typhimurium elicit host-specific chemokine profiles in animal models of typhoid fever and enterocolitis

Infection of bovine ligated loops with the Salmonella enterica serotype Typhimurium wild type but not a sipA sopABDE2 mutant resulted in fluid accumulation, polymorphonuclear cell infiltration, and expression of CXC chemokines, particularly GROalpha. None of these sipA sopABDE2-dependent responses was observed in murine-ligated loops. The majority of GROalpha transcripts localized to bovine intestinal epithelium. Thus, different disease outcomes between mice (i.e., no diarrhea) and calves (i.e., diarrhea) may be due to differences in sipA sopABDE2-dependent CXC chemokine gene expression in epithelial cells.