SERPINF1 and proliferative diabetic retinopathy: Since in the eye the physiological function of PEDF is the maintenance of a neuroprotective microenvironment to allow proper neuronal function, which includes the inhibition of abnormal retinal and choroidal blood vessel growth, increasing the level of PEDF would be the ideal therapy for the neovascularization that accompanies AMD and proliferative diabetic retinopathy.