Multilayered trabecular meshwork for dynamic in vitro studies in glaucoma research

Glaucoma, an eye disease causing incremental vision loss, currently has no cure. Its primary cause is the malfunction of the trabecular meshwork (TM), a multilayered tissue in the eye responsible for draining aqueous humor (AH) from the anterior chamber. TM clogging increases outflow resistance, elevates intraocular pressure (IOP), and damages optic nerves, leading to irreversible blindness. Existing in vitro TM models are suboptimal, as they lack the hierarchical structure of the TM. This article introduces a dynamic in vitro TM model, featuring a multilayered scaffold architecture 3D printed via melt electrowriting (MEW), and integrated with a flow system that enables continuous pressure monitoring during perfusion at native flow rates. Printed scaffolds supported the growth of primary adult human TM cells that grew on top and between the fibers. Cellularized scaffolds were tested under static and dynamic conditions. Over 3-5 days, pressure monitoring showed increased outflow resistance due to cell proliferation. Proteomic analysis revealed distinct changes in protein expression related to protein synthesis and respiration of cells grown under flow. Lat-B administration resulted in decreased pressure values and depolymerized actin filaments. These findings suggest that the proposed model is a promising alternative for in vitro glaucoma drug testing. STATEMENT OF SIGNIFICANCE: This study introduces a model of the trabecular meshwork (TM), a tissue in the eye involved in glaucoma, a common eye disease that currently has no cure. Using 3D printing, we created a multilayered scaffold that mimics the structure and function of the human TM. This allows us to study how cells behave and how drugs work under realistic conditions. Unlike existing models, ours accurately replicates all three layers of the TM, providing an advanced dynamic platform for glaucoma research. This innovation could help develop new treatments by offering a more reliable model for testing drugs and understanding how glaucoma works, making a significant impact on eye research.