Isolation of Mouse Retinal Capillaries and Subendothelial Matrix for Stiffness Measurement Using Atomic Force Microscopy

Vascular inflammation is known to cause degeneration of retinal capillaries in early diabetic retinopathy, which is a major vision-threatening microvascular complication of diabetes. Our lab is investigating whether and how mechanical cues in the form of vascular stiffness can contribute to these abnormal retinal vascular changes in early diabetes. There's a growing interest in developing ways to prevent diabetic retinopathy at the early stage with a particular focus on inhibiting retinal inflammation that occurs early on in diabetes and contributes to retinal neurovascular dysfunction.

Our recent work indicates that in addition to genetic and biochemical factors, mechanical cues such as vascular stiffness can promote retinal inflammation in early diabetes. Our protocol will allow researchers to isolate intact retinal vessels and subendothelial matrix for subsequent stiffness measurements using atomic force microscope. These measurements will help determine the role of vascular stiffness and endothelial mechanobiology in the development of vascular defects associated with diabetic retinopathy and macular degeneration.

By applying minute nano two picton level interation forces, atomic force microscopy offers a sensitive, accurate, and reliable technique to directly measure the stiffness of soft biological samples such as blood vessels, cells, and accessible metrics. To our knowledge, such gentle measurements are uniquely possible using an atomic force microscope. Our recent work has shown that retinal capillaries become stiffer in diabetes, which leads to retinal vascular inflammation and degeneration.

A deeper understanding of the mechanical regulation of the diabetic retinopathy as the potential to identify microbiology based anti-inflammatory targets for more effective therapies in the future.