Enterococcus faecalis is a member of the human gastrointestinal microbiota and is an opportunistic pathogen associated with hospital-acquired infections (HAIs) of wounds, the bloodstream, and the urinary tract. E. faecalis has the ability to subvert or evade immune-mediated clearance, although the mechanisms underlying this are poorly understood. In this study, we examine the ability of E. faecalis to subvert macrophage activation. We show that E. faecalis actively prevents NF-κB driven signaling in mouse RAW264.7 macrophages both in the presence of Toll-like receptor agonists and during polymicrobial infection with Escherichia coli. Co-infection with E. faecalis and E. coli in a mouse model of catheter-associated urinary tract infection (CAUTI) results in a reduced macrophage transcriptional response in the bladder compared to E. coli infection alone. Finally, we demonstrate that co-inoculation of E. faecalis with E. coli into the catheterized bladder significantly augments E. coli CAUTI. Taken together, these results implicate E. faecalis suppression of NF-κB-driven responses in macrophages with polymicrobial CAUTI pathogenesis.

Enterococcus faecalis Promotes Innate Immune Suppression And Polymicrobial Catheter-Associated Urinary Tract Infection