Join us in celebrating outstanding contributions to ophthalmology at the COS Awards of Excellence Ceremony. This special event will honor the recipients of the Paper and Poster Awards, recognizing their exceptional research and innovation. Paper award winners will be presented with their awards, while poster winners will have the opportunity to showcase their winning work.

Author’s Name(s): James Armstrong, Matthew Fung, Anastasiya Vinokurtseva, Victoria Leung, Richard Zhang, Hong Liu, Cindy Hutnik 

Author’s Disclosure Block: James Armstrong, none; Matthew Fung, none; Anastasiya Vinokurtseva, none; Victoria Leung, none; Richard Zhang, none; Hong Liu, none; Cindy Hutnik, none 

Abstract Body

Purpose: The success of bleb-forming glaucoma surgery is contingent on the continued diffusion of aqueous through subconjunctival tissues. Fibroblasts in the subconjunctival space are the mediators of post-operative tissue porosity. Novel inflammatory cytokines, such as TGFβ1, and mechanical stimuli associated with the flow of aqueous promote cellular actions that directly decrease tissue porosity. This study explores the effect of netarsudil, a Rho kinase inhibitor, on subconjunctival f ibroblasts and its capacity to mitigate fibroblast-mediated, post-surgical reductions in subconjunctival tissue porosity. Study Design:  The effect of netarsudil on afferent perfusate pressure was assessed within an in vitro microfluidic model of the subconjunctival outflow tract. A 3D tissue mimetic was created by embedding human Tenon’s capsule fibroblasts (HTCFs) within a collagenous extracellular matrix with perfusion to simulate aqueous humor flow. Methods: HTCFs were cultured inside a 3D collagen matrix within a microfluidics chamber slide. A syringe pump was used to perfuse culture media through the HTCF-containing collagen matrix at 2.6 µl/min. A pressure transducer was placed afferent to the HTCF-containing matrix to record pressure values over 72 hours as a surrogate measure to intraocular pressure. Experimental groups were determined by perfusate additives: 1) culture media, 2) culture media with TGFβ1 (2 ng/ml), or 3) culture media with TGFβ1 (2 ng/ml) and netarsudil (1mM). At experiment conclusion, slides were stained with DAPI and F-actin molecular probes. Afferent perfusion pressure curves were compared between groups using repeated measures ANOVA and morphology was compared semi-quantitatively using confocal laser scanning microscopy. Results: At 72-hours, mean ± SD afferent perfusion pressures in the TGFβ1 group (55.0 ± 7.3 mmHg) were significantly higher than control (24.1 ± 5.9 mmHg) and netarsudil (12.4 ± 3.36 mmHg) groups. Netarsudil significantly attenuated the morphological changes induced by TGFβ1 on human Tenon’s capsule fibroblasts, reducing cytoskeletal enlargement and cellular extensions into the extracellular matrix. Conclusions: This in vitro perfused HTCF model demonstrated increased resistance to perfusion with both culture media alone and culture media containing TGFβ1. Netarsudil mitigated these effects which supports the enticing possibility that it may have the off-target effect of blunting the fibroblastmediated reductions to outflow capacity in the subconjunctival tissues after glaucoma filtration surgery.