Abstract
Purpose :
Enterococcus faecalis (E. faecalis) is an important cause of endophthalmitis that results in significant vision loss and blindness. Bacteriophages (phages) are viruses widely-present in environment and infect, lyse, and kill bacteria without damage to mammalian cells. The aim of the present study was to develop novel topical phage therapy for infectious eye diseases, we investigated the therapeutic effects of single-dose intravitreous administration of E. faecalis–specific phage ΦEF24C-P2 on Enterococcus faecalis endophthalmitis in mice.
Methods :
Endophthalmitis was induced in mice by injection of 1 × 104 E. faecalis bacteria into the vitreous body. Bacteriophage ΦEF24C-P2 was then injected into the vitreous 6h after bacterial injection. Eyes were examined 1 day after infection to grade disease severity according to an established scale. The number of viable bacteria in the eye was determined, and infiltrated inflammatory cells in the eye were quantitated by assay of myeloperoxidase activity. Pathological examination was also performed.
Results :
Injection of the eye with E. faecalis induced severe endophthalmitis, with the ocular fundus being invisible due to fibrin precipitation or hemorrhage in the anterior chamber at 24 h. Single-dose administration of phage ΦEF24C-P2 into the vitreous resulted in significant attenuation of disease severity. ΦEF24C-P2 treatment also suppressed the number of viable bacteria and neutrophil infiltration in the infected eye. Pathological examination revealed massive inflammatory cell infiltration and retinal detachment in vehicle-treated eyes, whereas cell infiltration was attenuated and retinal structure was preserved in phage-treated eyes.
Conclusions :
Administration of phage into the vitreous body is effective for treatment of E. faecalis endophthalmitis and is a potential novel adjunct or alternative option for the treatment of bacterial endophthalmitis.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.