Invasive Escherichia coli vaccines expressing Brucella melitensis outer membrane proteins 31 or 16 or periplasmic protein BP26 confer protection in mice challenged with B. melitensis

► Non-pathogenic invasive Escherichia coli used as a vaccine platform to mimic Brucella melitensis. ► Invasive E. coli expressing B. melitensis Omps induce IFN-γ and cytotoxic T cells. ► Vaccine platform expressing Omps induceantibodies and T cell proliferation. ► Invasive E. coli expressing Omps protect against B. melitensis challenge.