Effects of antibiotics on morphologic characteristics and migration of canine corneal epithelial cells in tissue culture

Objective-To determine effects of commonly used ophthalmic antibiotics on cellular morphologic characteristics and migration of canine corneal epithelium in cell culture. Sample Population-Corneal epithelial cells harvested from corneas of 12 euthanatized dogs and propagated in cell culture. Procedure-Cells were treated with various antibiotics after a defect was created in the monolayer. Cellular morphologic characteristics and closure of the defect were compared between antibiotic-treated and control cells. Results-Cells treated with ciprofloxacin and cefazolin had the greatest degree of rounding, shrinkage, and detachment from plates. Cells treated with neomycin-polymyxin B-gramicidin and gentamicin sulfate had rounding and shrinkage but with less detachment. Cells treated with tobramycin and chloramphenicol grew similarly to control cells. On the basis of comparisons of defect circumference between control cells and cells exposed to antibiotics, tobramycin affected cellular migration the least. Conclusions and Clinical Relevance-Effects of ciprofloxacin and cefazolin on morphologic characteristics of canine corneal epithelial cells in vitro should be taken into consideration before using these antibiotics for first-line of treatment for noninfected ulcers. Of the antibiotics tested that have a primarily gramnegative spectrum of coverage, gentamicin inhibited corneal epithelial cell migration and had greater cytopathologic effects than tobramycin did. For antibiotics with a gram-positive coverage, chloramphenicol had no cytopathologic effects on cells in comparison to cefazolin, which caused most of the cells to shrink and detach from the plate. Polymyxin B-neomycin-gramicidin was midrange in its effects on cellular morphologic characteristics and migration.