Vitronectin: a migration and wound healing factor for human corneal epithelial cells

Area of Science:

• Ophthalmology
• Cell Biology
• Biomaterials Science

Background:

• The cornea's stratified squamous epithelium is a primary defense against injury.
• Delayed corneal healing can occur when epithelial cells fail to adhere to the basement membrane.
• Vitronectin (VN) is an extracellular matrix protein involved in cell adhesion and migration.

Purpose of the Study:

• To investigate the role of vitronectin (VN) in promoting corneal epithelial wound healing.
• To determine if VN enhances the rate of epithelial recovery after corneal injury.

Main Methods:

• Cultured primary human corneolimbal epithelial cells and a human corneal epithelial cell (HCEC) line were used to assess wound closure rates.
• Human corneas in organ culture underwent debridement, followed by application of therapeutic contact lenses (CLs) with or without VN.
• Histological assessment was performed after 7 days to evaluate epithelialization.

Main Results:

• Vitronectin (5 μg/mL) significantly accelerated wound closure in both cultured HCECs and primary corneal epithelial cells.
• Wound healing was inhibited by an RGD peptide, an anti-VN antibody, and by silencing β5-integrin, indicating VN's mechanism involves integrin signaling.
• VN did not affect cell proliferation but enhanced re-epithelialization in ex vivo human corneas when delivered via CLs.

Conclusions:

• Vitronectin is crucial for expediting corneal epithelial wound recovery, acting both in vitro and ex vivo.
• Therapeutic contact lenses loaded with VN represent a potential strategy for treating persistent corneal epithelial defects.
• VN's ability to promote cell adhesion and migration is key to its therapeutic effect on ocular surface wounds.