TY - JOUR
T1 - Cross-talk among flesh-eating Aeromonas hydrophila strains in mixed infection leading to necrotizing fasciitis
JF - Proceedings of the National Academy of Sciences
Y1 - 2016
A1 - Ponnusamy, Duraisamy
A1 - Kozlova, Elena V.
A1 - Sha, Jian
A1 - Erova, Tatiana E.
A1 - Azar, Sasha R.
A1 - Fitts, Eric C.
A1 - Kirtley, Michelle L.
A1 - Tiner, Bethany L.
A1 - Andersson, Jourdan A.
A1 - Grim, Christopher J.
A1 - Isom, Richard P.
A1 - Hasan, Nur A.
A1 - Rita R Colwell
A1 - Chopra, Ashok K.
AB - Necrotizing fasciitis (NF) caused by flesh-eating bacteria is associated with high case fatality. In an earlier study, we reported infection of an immunocompetent individual with multiple strains of Aeromonas hydrophila (NF1–NF4), the latter three constituted a clonal group whereas NF1 was phylogenetically distinct. To understand the complex interactions of these strains in NF pathophysiology, a mouse model was used, whereby either single or mixed A. hydrophila strains were injected intramuscularly. NF2, which harbors exotoxin A (exoA) gene, was highly virulent when injected alone, but its virulence was attenuated in the presence of NF1 (exoA-minus). NF1 alone, although not lethal to animals, became highly virulent when combined with NF2, its virulence augmented by cis-exoA expression when injected alone in mice. Based on metagenomics and microbiological analyses, it was found that, in mixed infection, NF1 selectively disseminated to mouse peripheral organs, whereas the other strains (NF2, NF3, and NF4) were confined to the injection site and eventually cleared. In vitro studies showed NF2 to be more effectively phagocytized and killed by macrophages than NF1. NF1 inhibited growth of NF2 on solid media, but ExoA of NF2 augmented virulence of NF1 and the presence of NF1 facilitated clearance of NF2 from animals either by enhanced priming of host immune system or direct killing via a contact-dependent mechanism.
VL - 11312161268
UR - http://www.pnas.org/lookup/doi/10.1073/pnas.1523817113
CP - 3321029
J1 - Proc Natl Acad Sci USA
M3 - 10.1073/pnas.1523817113
ER -