Development of a 3D Human Trabecular Meshwork Cell Culture System Using Natural Biopolymer Scaffolds - Project Summary
Aqueous humor outflow resistance is the primary determinant of intraocular pressure (IOP); increased
outflow resistance is the basis for elevated IOP associated with glaucoma. In humans, IOP is primarily
controlled by the outflow of the aqueous humor through the trabecular meshwork (TM). Researchers trying
to screen new therapeutics for glaucoma, or elucidate TM cell behavior under various conditions, currently
have the option of screening the response of TM cells cultured on flat two-dimensional plastic cell culture
dishes, or screening the response of the TM using perfusion studies of donor eyes, which are expensive
studies. Most in vitro studies of TM are over-simplified since there is a significant difference between the
flat two-dimensional plastic surfaces on which the TM cells are traditionally cultured and the complex three-
dimensional in vivo environment. The topographic features and biomechanic stresses present in vivo
provide the cells with stimuli that influence their proliferation, migration, adhesion, and extracellular
matrix (ECM) deposition. Our central hypothesis is that a novel constant flow perfusion system that utilizes
a natural biopolymer scaffold with anisotropic pore structure to mimic more closely the trabecular
meshwork cells' microenvironment can support TM cell growth and provide a platform that could be used
for effective screening of various bioactive stimuli. From a biological and biomimetic point of view, natural
polymers are desirable to use as biomaterial scaffolds, as their properties are very similar to the native ECM.
Collagen, chondroitin sulfate (CS) and hyaluronic acid (HA) are the most predominant components of ECM
of native TM. For this project, collagen-CS/HA scaffolds that have uniaxally aligned pores will be engineered
to support TM cell growth. This proposal consists of three aims: (1) To determine the effect of hyaluronic
acid and chondroitin sulfate on hTM cell growth and ECM production in our 3D collagen scaffolds; (2) To
determine the influence of perfusion on the 3D hTM cell-seeded scaffolds; (3) To determine the effect of
dexamethasone, TGF-β2, and Latrunculin B (Lat B) on the 3D hTM cell-seeded scaffolds under static and
perfusion culture conditions. This 3D TM cell culture system will bring a huge advance to the field of
glaucoma research and drug screening by establishing a system that allows the study of TM cells in an
environment that more closely simulates their microenvironment, thus producing more physiologically
relevant data. The potential impact this could ultimately have on patients is immense, as there are nearly
70 million people in the world that suffer from glaucoma. Furthermore, this research will provide exposure
of graduate and undergraduate students to biomedical research at a university without an established
bioengineering or biology department that has been traditionally focused on earth and energy sciences.