C-X-C Chemokines Influence Intraocular Inflammation During Bacillus Endophthalmitis

PURPOSE: The purpose of this study was to explore the C-X-C chemokines CXCL2 and CXCL10 as potential anti-inflammatory targets for Bacillus endophthalmitis. METHODS: Bacillus endophthalmitis was induced in C57BL/6J, CXCL2(−/−), and CXCL10(−/−) mice. At specific times postinfection, eyes were analyzed for Bacillus, retinal function, and inflammation. The efficacies of intravitreal anti-CXCL2 and anti-CXCL10 with or without gatifloxacin in B. cereus endophthalmitis were also assessed using the same techniques. RESULTS: Despite similar Bacillus growth in eyes of C57BL/6J, CXCL2(−/−), and CXCL10(−/−) mice, retinal function retention was greater in eyes of CXCL2(−/−) and CXCL10(−/−) mice compared to that of C57BL/6J mice. Neutrophil migration into eyes of CXCL2(−/−) and CXCL10(−/−) mice was reduced to a greater degree compared to that of eyes of C57BL/6J mice. Infected CXCL2(−/−) and CXCL10(−/−) mouse eyes had significantly less inflammation compared to that of C57BL/6J eyes. Retinal structures in infected eyes of CXCL2(−/−) mice were preserved for a longer time than in CXCL10(−/−) eyes. Compared to untreated eyes, there was less inflammation and significant retention of retinal function in eyes treated with anti-CXCL2 and anti-CXCL10 with or without gatifloxacin. CONCLUSIONS: For Bacillus endophthalmitis, the absence of CXCL2 or CXCL10 in mice resulted in retained retinal function and less inflammation. The absence of CXCL2 led to a better clinical outcome than the absence of CXCL10. The use of anti-CXCL2 and anti-CXCL10 limited inflammation during B. cereus endophthalmitis. These results highlight the utility of CXCL2 and CXCL10 as potential targets for anti-inflammatory therapy that can be tested in conjunction with antibiotics for improving treating Bacillus endophthalmitis.