Mitigation of neutrophil infiltration in a rat model of early Staphylococcus aureus endophthalmitis.
نویسندگان
چکیده
PURPOSE Infectious endophthalmitis is characterized by neutrophil migration into the eye. The purpose of this study was to determine whether systemic neutrophil depletion mitigates the ocular influx of neutrophils during the early phases of experimental endophthalmitis. METHODS Endophthalmitis was induced in rats by intravitreal injection of Staphylococcus aureus. Animals received a single systemic dose of an anti-neutrophil-depleting antibody (dAb) or normal rabbit serum (NRS) 6 or 12 hours after intravitreal injection. Inflammation was graded both in vivo and by histopathology. Myeloperoxidase (MPO) was used as a biomarker of neutrophil infiltration. Bacterial clearance was evaluated by determining the amount of viable bacteria recovered from ocular specimens. RESULTS Rats that received dAb 6 hours after bacterial injection exhibited significantly lower clinical scores, MPO activity, fewer vitreous exudates, and higher vitreous bacterial counts at 24 hours (P < 0.05). As the neutrophil population returned in this group, measured by the number in the peripheral blood, increasing intraocular inflammation was observed. Rats receiving dAb 12 hours after vitreous injection also demonstrated significantly lower clinical scores, MPO activity and less vitreous exudates at the 24-hour time point (P < 0.05). No significant differences from the control were detected at any of the subsequent time points, except in bacterial counts and MPO activity. CONCLUSIONS Depletion of neutrophils early in the inflammatory response delayed the onset of severe ocular inflammation but also prevented adequate bacterial clearance. These results confirm the important role of neutrophils in ocular host defense during the early stages of experimental endophthalmitis.
منابع مشابه
Intravitreal injection of the chimeric phage endolysin Ply187 protects mice from Staphylococcus aureus endophthalmitis.
The treatment of endophthalmitis is becoming very challenging due to the emergence of multidrug-resistant bacteria. Hence, the development of novel therapeutic alternatives for ocular use is essential. Here, we evaluated the therapeutic potential of Ply187AN-KSH3b, a chimeric phage endolysin derived from the Ply187 prophage, in a mouse model of Staphylococcus aureus endophthalmitis. Our data sh...
متن کاملSecretory Leukocyte Protease Inhibitor Is an Inducible Antimicrobial Peptide Expressed in Staphylococcus aureus Endophthalmitis
PURPOSE To describe the presence of secretory leukocyte protease inhibitor (SLPI), a cationic peptide with antimicrobial and antiprotease activity, in the innate ocular immune reaction in a rat model of Staphylococcus aureus endophthalmitis. METHODS Seventy-five female Lewis rats were divided into three groups: the endophthalmitis group received an intravitreal injection of 65 colony-forming ...
متن کاملIntravitreal human immune globulin in a rabbit model of Staphylococcus aureus toxin-mediated endophthalmitis: a potential adjunct in the treatment of endophthalmitis.
OBJECTIVES To test the feasibility of human immune globulin (IG, Gamimune N, 10%) as a new treatment for endophthalmitis, the ocular tolerance, distribution, and ability of intravitreal IG to attenuate the toxic effects of Staphylococcus aureus culture supernatant were evaluated in a rabbit model. METHODS Effects of intravitreally injected IG were assessed histologically and with Western blot...
متن کاملRole of Staphylococcus aureus Virulence Factors in Inducing Inflammation and Vascular Permeability in a Mouse Model of Bacterial Endophthalmitis
Staphylococcus (S.) aureus is a common causative agent of bacterial endophthalmitis, a vision threatening complication of eye surgeries. The relative contribution of S. aureus virulence factors in the pathogenesis of endophthalmitis remains unclear. Here, we comprehensively analyzed the development of intraocular inflammation, vascular permeability, and the loss of retinal function in C57BL/6 m...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- Investigative ophthalmology & visual science
دوره 44 7 شماره
صفحات -
تاریخ انتشار 2003