Tarsal inflammatory response after topical prostaglandin analogues treatment ‐ pilot study

Abstract

PurposeTo describe impact of topical preservative‐free (PF) prostaglandin analogues on inflammatory response within eyelid tarsus.MethodsNew Zealand rabbits’ eyes (n = 12 animals) were exposed to topical PF prostaglandins for 8 weeks daily. Each right eye was treated and each left eye kept as a control – topical PBS application. As eye drops we used PF tafluprost (Taflotan, Santen), PF latanoprost (Monoprost, Thea) and PF bimatoprost (Lumigan, Allergan). After 8 weeks animals were sacrificed, eyelids were post‐fixed in 4% paraformaldehyde and embedded in paraffin. Tarsal sections were immunostained for macrophage‐specific Iba‐1 and mucin. Tissue histology was evaluated by Masson trichrome staining. Quantitative analysis of macrophages (MFs) infiltration within tarsal: conjunctiva, stroma and glands was performed.ResultsPF prostaglandin treatment for 8 weeks did not affect mucin expression within analyzed tissues. Total number of MFs forming infiltration in tarsal conjunctiva of PF tafluprost group was 3.5 ± 2.5 vs 2.2 ± 1.5 cells (p > 0.05, respectively for treated vs control eye), in PF latanoprost group was 11.6 ± 9.8 vs 3.8 ± 1.8 cells (p < 0.05) and in PF bimatoprost group was 6.8 ± 5.1 vs 3.9 ± 2.5 (p = 0.05). There was significantly different intensity of MFs infiltration within tarsal conjunctiva between groups: PF latanoprost>PF bimatoprost>PF tafluprost (p < 0.05, Kruskal‐Wallis test). MFs infiltration within tarsal stroma and glands was slightly increased in PF latanoprost group when compared with control (p < 0.05), however it was not significantly different from other prostaglandins (p > 0.05).ConclusionsApplied PF prostaglandin analogues affected MFs infiltration within tarsus. The strongest macrophage‐associated inflammatory reaction was related to PF latanoprost application, however there is a need for further analyses of other inflammatory response pathways.