Bacteriophage therapy for Staphylococcus aureus biofilm-infected wounds: a new approach to chronic wound care.
BACKGROUND
Bacterial biofilms, which are critical mediators of chronic wounds, remain difficult to treat with traditional methods. Bacteriophage therapy against biofilm has not been rigorously studied in vivo. The authors evaluate the efficacy of a species-specific bacteriophage against Staphylococcus aureus biofilm-infected wounds using a validated, quantitative, rabbit ear model.


METHODS
Six-millimeter dermal punch wounds in New Zealand rabbit ears were inoculated with wild-type or mutant, biofilm-deficient S. aureus. In vivo biofilm was established and maintained using procedures from our previously published wound biofilm model. Wounds were left untreated, or treated every other day with topical S. aureus-specific bacteriophage, sharp débridement, or both. Histologic wound healing and viable bacterial count measurements, and scanning electron microscopy were performed following harvest.


RESULTS
Wild-type S. aureus biofilm wounds demonstrated no differences in healing or viable bacteria following bacteriophage application or sharp débridement alone. However, the combination of both treatments significantly improved all measured wound healing parameters (p < 0.05) and reduced bacteria counts (p = 0.03), which was confirmed by scanning electron microscopy. Bacteriophage treatment of biofilm-deficient S. aureus mutant wounds alone also resulted in similar trends for both endpoints (p < 0.05).


CONCLUSIONS
Bacteriophages can be an effective topical therapy against S. aureus biofilm-infected wounds in the setting of a deficient (mutant) or disrupted (débridement) biofilm structure. Combination treatment aimed at disturbing the extracellular biofilm matrix, allowing for increased penetration of species-specific bacteriophages, represents a new and potentially effective approach to chronic wound care. These results establish principles for biofilm therapy that may be applied to several different clinical and surgical problems.
Chicago, Ill.; and Fort Sam Houston, Texas From the Division of Plastic and Reconstructive Surgery, Feinberg School of Medicine, Northwestern University, and the Microbiology Branch, U.S. Army Dental and Trauma Research Detachment, Institute of Surgical Research.
Akhil K
AK
Seth
Matthew R
MR
Geringer
Khang T
KT
Nguyen
Sonya P
SP
Agnew
Zari
Z
Dumanian
Robert D
RD
Galiano
Kai P
KP
Leung
Thomas A
TA
Mustoe
Seok J
SJ
Hong
D000818:Animals; D001435:Bacteriophages; D018441:Biofilms; D002908:Chronic Disease; D011817:Rabbits; D013203:Staphylococcal Infections / Q000382:microbiology* / Q000628:therapy*; D013211:Staphylococcus aureus / Q000502:physiology*; D014946:Wound Infection / Q000382:microbiology* / Q000628:therapy*