Rapid Induction of an Immune Response in Rat Peyer's Patch after Oral Administration of Enterococcus faecalis Strain EC-12

A rapid and sharp immune response induced in Peyer's patches (PPs) by a single gavage of a heat-killed Enterococcus faecalis strain EC-12 (EC-12) was demonstrated. EC-12 was observed inside the PPs 2.5 h post administration and induction of TNE-alpha and CD69 gene expression was observed at the same time. The immune response in PPs disappeared 24 h post administration.