Inhibition of Corneal Inflammation by the Resolvin E1

PURPOSE. To investigate the role of the lipid mediator, resolvin E1 (RvE1), in corneal inflammation. METHODS. The effect of RvE1 on stimulated human corneal epithelial cells (HCECs) and neutrophils, and mouse macrophage was assessed. C57BL/6 mouse corneas were abraded and treated with RvE1 either before or after stimulation with lipopolysaccharide (LPS) and antibiotic-killed Pseudomonas aeruginosa and Staphylococcus aureus. The levels of CXC chemokines in the cornea were quantified, and the presence of neutrophils in corneal infiltrates was detected by immunohistochemistry and by in vivo confocal microscopy. The effect of RvE1 on apoptosis in the corneal epithelium was assessed using the TUNEL assay. RESULTS. RvE1 significantly inhibited cytokine production in HCECs and neutrophils, and mouse macrophages and cornea. The development of corneal infiltrates, specifically neutrophils, in response to stimulation with LPS, P. aeruginosa, and S. aureus was also significantly reduced. There was no apoptotic effect of RvE1 on mouse corneal epithelial cells. CONCLUSIONS. RvE1 inhibits corneal inflammation induced by LPS, Gram negative (P. aeruginosa) and Gram positive (S. aureus) bacteria. These findings indicate that RvE1 as a potential anti-inflammatory therapy for patients with corneal inflammation and also, when given together with antibiotics, for bacterial keratitis.