Enterococcus faecalis Modulates Immune Activation and Slows Healing During Wound Infection

J Infect Dis. 2017 Dec 19;216(12):1644-1654. doi: 10.1093/infdis/jix541.


Enterococcus faecalis is one of the most frequently isolated bacterial species in wounds yet little is known about its pathogenic mechanisms in this setting. Here, we used a mouse wound excisional model to characterize the infection dynamics of E faecalis and show that infected wounds result in 2 different states depending on the initial inoculum. Low-dose inocula were associated with short-term, low-titer colonization whereas high-dose inocula were associated with acute bacterial replication and long-term persistence. High-dose infection and persistence were also associated with immune cell infiltration, despite suppression of some inflammatory cytokines and delayed wound healing. During high-dose infection, the multiple peptide resistance factor, which is involved in resisting immune clearance, contributes to E faecalis fitness. These results comprehensively describe a mouse model for investigating E faecalis wound infection determinants, and suggest that both immune modulation and resistance contribute to persistent, nonhealing wounds.

Keywords: Enterococcus faecalis; immune evasion; multiple peptide resistant factor; persistence; wound infection.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Disease Models, Animal
  • Enterococcus faecalis / growth & development
  • Enterococcus faecalis / immunology*
  • Enterococcus faecalis / pathogenicity*
  • Gram-Positive Bacterial Infections / microbiology
  • Gram-Positive Bacterial Infections / pathology*
  • Immune Evasion*
  • Male
  • Mice, Inbred C57BL
  • Wound Infection / microbiology
  • Wound Infection / pathology*