In Vitro Cell Models for Ophthalmic Drug Development Applications

Abstract

Tissue engineering is a rapidly expanding field that aims to establish feasible techniques to fabricate biologically equivalent replacements for diseased and damaged tissues/organs. Emerging from this prospect is the development of in vitro representations of organs for drug toxicity assessment. Due to the ever-increasing interest in ocular drug delivery as a route for administration as well as the rise of new ophthalmic therapeutics, there is a demand for physiologically accurate in vitro models of the eye to assess drug delivery and safety of new ocular medicines. This review summarizes current existing ocular models and highlights the important factors and limitations that need to be considered during their use.

Keywords: cell culture; drug delivery; ophthalmology; tissue engineering; toxicity testing.

FIG. 1.

Schematic diagram of the human eye.

FIG. 2.

Schematic presentation of different layers of the cornea.

FIG. 3.

Schematic presentation of a corneal equivalent in vitro culture model: (A) Corneal endothelial cells are grown to confluency on a culture insert. (B) A collagen layer containing stromal cells is grown on top of the corneal endothelial cell layer. (C) Epithelial cells are seeded on top of the collagen layer. (D) Exposure to air–liquid interface results in a stratified epithelium.

FIG. 4.

Schematic presentation of the functions of the retinal pigment epithelium within the retina.