Consensus recommendations for trabecular meshwork cell isolation, characterization and culture

Abstract

Cultured trabecular meshwork (TM) cells are a valuable model system to study the cellular mechanisms involved in the regulation of conventional outflow resistance and thus intraocular pressure; and their dysfunction resulting in ocular hypertension. In this review, we describe the standard procedures used for the isolation of TM cells from several animal species including humans, and the methods used to validate their identity. Having a set of standard practices for TM cells will increase the scientific rigor when used as a model, and enable other researchers to replicate and build upon previous findings.

Keywords: Aqueous humor dynamics; Conventional outflow; Glaucoma; Intraocular pressure; Ocular hypertension.

Fig. 1

Anatomy of the Trabecular Meshwork (TM). Light micrograph of meridional section through the human TM. Region between dotted lines indicate filtering portion of TM. Panel B is a magnification of A. Magnification bars: 20 μm (A), 5 μm (B); SC: Schlemm’s canal, SS: scleral spur, CM: ciliary muscle, UTM: Uveal TM, CTM: corneoscleral TM, JCT: juxtacanalicular tissue, AC: anterior chamber. Modified from Tamm (2009).

Fig. 2

Micrograph showing removal of TM tissue from a human donor eye as a strip. Yellow arrows indicate region where TM has been removed. White arrow shows intact TM.

Fig. 3

Phase contrast images of early and late passage (p2 vs p6) confluent TM cell cultures from the same human donor (11 month old). Arrows point to senescent cells.

Fig. 4

Phase-contrast images of three different human TM cell strains in culture, showing a spectrum of morphologies. Modified from Stamer and Clark (2017).