PAI-1 is a vascular cell-specific HIF-2-dependent angiogenic factor that promotes retinal neovascularization in diabetic patients.

The article hypothesized that vascular cells within neovascular tissue secrete autocrine/paracrine angiogenic factors that promote disease progression. It discusses that multiplex ELISA angiogenesis arrays was performed on aqueous fluid from proliferative diabetic retinopathy patients who responded inadequately to anti-vascular endothelial growth factor therapy and/or n pan-retinal scatter laser photocoagulation and identified plasminogen activator inhibitor-1 (PAI-1).