THE UBIQUITIN PATHWAY IN CORNEAL SCARRING

Project Summary: The ubiquitin pathway in corneal scarring
Scarring in the cornea resulting from injury, trauma, or infection can lead to debilitating opacities and
permanent vision loss. Acute scarring, similar to chronic fibrosis, is characterized by immune cell
infiltration and the persistence of cells termed myofibroblasts. We have found that the deubiquitinase
(DUB) USP10 is a key regulator of scarring pathways in the cornea. Knockdown of USP10 in vivo leads
to a significant reduction in the development of myofibroblasts, cell apoptosis, the presence of CD45+
immune cells, and fibrotic extracellular matrix in a healing wound. We are proposing to test the central
hypothesis that USP10 is a key regulator of myofibroblast persistence in a corneal scar via its multi-
factorial role in wound healing. Specifically, since USP10 is a DUB for αv-integrins and p53, in Specific
Aim 1 we will unravel the complex role of USP10 in integrin recycling and p53 dynamics in primary
human corneal fibroblasts and in mice in vivo. The communication between fibroblasts and
macrophages plays a critical role in scarring outcomes. In Specific Aim 2 we will develop novel 3D and
2.5D hydrogel systems with “tunable stiffness” that mimic a 3D environment close to the stiffness of the
healing cornea. Using these hydrogels, mouse corneal fibroblasts will be cocultured with mouse bone
marrow derived macrophages (M0/M1/M2) to elucidate the role of USP10 in macrophage-mediated
myofibroblast development and contraction. In Specific Aim 3 using three separate mouse models we
will assess the role of USP10 in immune cell infiltration into a corneal wound.

Grant Number: 5R01EY024942-07
NIH Institute/Center: NIH
Principal Investigator: AUDREY BERNSTEIN