TM/SC-interface-on-a-chip for mechanistic studies of outflow regulation.

PROJECT SUMMARY/ABSTRACT The trabecular meshwork (TM)/Schlemm’s canal (SC)-interface is critical for normal aqueous humor outflow function and intraocular pressure. Flow across the circumference of the outflow tract is non-uniform or segmental, with low-flow (LF) regions exhibiting higher extracellular matrix stiffness than high-flow (HF) regions. Dysfunction of the outflow tract causes decreased aqueous drainage and consequently increased intraocular pressure that poses a serious threat to normal vision. However, despite the strong association of outflow impairment with development of high-pressure glaucoma, the underlying mechanisms – including contributions from LF/HF regions – are incompletely understood. This largely stems from the inability of current outflow tissue models to precisely simulate the dynamic TM/SC-interface at high resolution necessary for in- depth mechanistic studies. To overcome critical limitations of previous outflow tissue replicas, this work seeks to generate a first-in-class TM/SC-interface-on-a-chip that accurately recapitulates the outflow tissue’s complex microenvironment and segmental elasticity profile. The novel 3D outflow tissue platform allows us to dissect the mechanisms of resistance generation by selectively manipulating individual outflow pathway components in ways otherwise not possible using other models. This will enable quantitative measurements of dynamic changes at the interface in real-time, while also being compatible with critical end-point tests. Based on key preliminary data acquired by our investigative team, we propose the following specific aims: Aim 1: Design and validate a microfluidic chip-based TM/SC-interface to investigate dynamic outflow regulation. Aim 2: Investigate segmental outflow regulation using localized ECM stiffness patterns containing region- specific TM cells.