Inhibition of EB3 activates the Meis2-Pax6 regenerative program in wet AMD [scATAC-seq]

Wet age-related macular degeneration (AMD), characterized by leaky neovessels emanating from the choroid, is a main cause of blindness. As current treatments for wet AMD require regular intravitreal injections of anti-VEGF biologics, there is a need for the novel development of less invasive treatments. Here, we developed a novel inhibitor of microtubule-associated End Binding 3 protein (EB3), herein termed EBIN, which blocked pathological Ca2+ signaling in activated endothelial cells and suppressed leakage of choroidal neovessels. Delivery of EBIN via eye drops in mouse and non-human primate (NHP) models of AMD prevented neovascular leakage and neovascularization as effectively as intravitreal injection of anti-VEGF therapy. EBIN activated Meis2-Pax6 regenerative pathways in metabolic-active endothelial cells comprising neovessels and promoted tissue regeneration. Furthermore, single nuclei assay for transposase-accessible chromatin sequencing (sn-ATAC-seq) analysis demonstrated that in metabolic-active endothelial cells, the RPE, and photoreceptors, EBIN induced global increases in chromatin accessibility, the biological process progressively inhibited in AMD patients. These results suggest the unique therapeutic mode of action of this novel drug candidate, which can potentially promote regeneration of eye tissue by reversing the degenerative processes underlying both the neovascular and atrophic forms of AMD. Overall design: Choroidal neovascularization was induced on day 0 in African green monkeys' eye by laser photocoagulation targeting the Bruch's membrane. Monkeys then received either 30 µL topical instillation of Myr-EBIN or vehicle in each eye twice daily for 7 days and once a day for another 14 days. After 21 days, the eyes were dissected and separated by different sections of the eyes. Samples that undergo sequencing were flash frozen and been sent to UC San Diego Center for Epigenomics for sample preparation and sequencing.