Transfer of resistance against reinfection in experimental infectious colitis by CD4+ Th1 cells

Citrobacter rodentium (C. r.) induces an acute, self-limited non-invasive colitis in mice which is associated with crypt hyperplasia. C. r. serves as a murine model for human infectious colitis induced by enterohemorrhagic and enteropathogenic E. coli (EHEC, EPEC). Previously infected mice have been reported to be refractory against reinfection with C. r.. We investigated if resistance against C. r. infection can be transferred from previously infected mice and the potential mechanisms mediating protection. Balb/c mice were orally infected with 5×108 CFU C. r.. The course of infection was assessed by fecal excre…