Abstract
Introduction::
Being a fourth generation fluorochinolon Moxifloxacin covers most Gram positive and negative isolates causing endophthalmitis, a rare but severe complication after intraocular surgery. It is safe and effective for systemic and topical use, however only very limited data are available for intravitreal administration in endophthalmitis. The current study investigates the safety of Moxifloxacin for intravitreal application in a cell culture model.
Methods::
Primary human retinal pigment epithelium cells (RPE) and ARPE19 cells were treated with concentrations of Moxifloxacin ranging from 10µg/mL to 1000µg/mL. Possible toxic effects and IC50 were evaluated after 24 hours and 48 hours as well as under conditions of oxidative stress. By treating the RPE cell lines with Tumor-Necrosis-Factor alpha (TNF-a; 10µg/mL), Lipopolysaccharides (LPS; 20µg/mL) and Interleucin 6 (IL-6; 20µg/mL) the effects of Moxifloxacin on cellular viability under conditions of inflammation were investigated. Toxicity was evaluated by colorimetric measuring the inhibition of RPE cell proliferation (MTT). Additionally cell viability was quantified by a microscopic live-dead-assay.
Results::
Only at concentrations higher than 250µg/mL Moxifloxacin showed adverse effects on primary RPE and ARPE19 cell proliferation and viability. Lower concentrations had no influence on RPE cell proliferation and cell viability when administered for 24 to 48 hours. When preincubated with TNF-a, LPS and IL-6 for 24 hours and subsequently treated with Moxifloxacin at concentrations from 10µg/ml to 200µg/ml for 24hrs no significant decrease in proliferation and viability were observed.
Conclusions::
This study showed that no significant toxicity existed for Moxifloxacin on primary RPE and ARPE19 cells when administered in concentrations less than 250µg/mL. The MIC90 of Moxifloxacin for pathogens commonly encountered in endophthalmitis is known to be in the range of 0.25µg/ml to 2.5µg/ml. Therefore the intravitreal use of Moxifloxacin at concentrations up to 150µg/mL could be safe and effective for endophthalmitis treatment.
Keywords: endophthalmitis • inflammation • bacterial disease