Impact of preserved and preservative‐free 0.005% latanoprost ophthalmic formulations on human conjunctival goblet cell survival

Abstract

AbstractPurposeTo compare the cell toxicity levels of preserved (P) and preservative‐free (PF) 0.005% latanoprost formulations used in glaucoma treatment, on pure cultures of human conjunctival goblet cells (GC), and to establish the physical properties of the various P and PF formulations, with respect to drop size distribution, pH, osmolarity, surface tension and the amount of latanoprost in each formulation.MethodsThe pureness of the cultured human conjunctival GC was established using PAS staining and immune‐staining specific for GC. The impact of the branded and generic P or PF latanoprost (Monoprost®). Latanoprost formulation on the GC survival was assessed using LDH cytotoxicity detection assay and MTT cell proliferation assay. Chemical properties of the ophthalmic formulations containing P or PF latanoprost was determined with respect to drop size distribution, pH, osmolarity, surface tension and the amount of latanoprost in each formulation.ResultsPAS and immuno‐staining showed the purity of the GC cultures. The GC survival was compromised when treating with P latanoprost, whereas when treating with PF latanoprost, the cells appeared not to be affected. Significant differences could be observed in regard to the pH, osmolality, surface tension, and drop size between the treatment modalities.ConclusionViability of pure GC cultures was decreased by P latanoprost formulations, whereas PF latanoprost did not cause GC death. The loss of conjunctival GC will produce dry eye symptoms in patients, which is the most described discomfort by the patient. More emphasis should therefore be placed on physicochemical properties and on the toxicity from using P latanoprost formulations when treating glaucoma patients.