Corneal epithelial disorders take pride of place in modern ophthalmology. Defects
of corneal epithelium are commonly accompanied by blurry vision, photophobia and tearing.
Since cornea is the most densely innervated tissue of organisms, its disruption leads to development
of a severe pain syndrome. Mild corneal erosions commonly undergo quick spontaneous
recovery. Suppression of corneal wound healing due to various pathological causes results
in development of severe recurrent erosions and persistent corneal defects. These pathological
events can in turn lead to corneal scarring, opacification, and ulceration of cornea, and ultimately
to the permanent vision impairment. The etiology of the underlying corneal diseases
that commonly involves inflammatory, neurotrophic and systemic factors, should be considered
for treating such defects. Therefore, the research focus has been shifted to establish
therapeutics based on proteins and peptides. Due to varied mechanisms of action, proteinbased
pharmaceuticals can be involved in the protection of corneal surface, mimicking tear
components, stimulation of corneal wound healing, regeneration of corneal innervation, suppressing
oxidative stress, inflammation and neovascularization. The active components can be
naturally occurring (blood- or tear-derived) or be created de novo and optimized in order to
achieve the level of activity required. Such pharmaceuticals are characterized by low toxicity
and absence of systemic side-effects due to their low absorption into the bloodstream, if administrated
topically. This review summarizes existing data on protein-based drugs for treatment
of corneal epithelial defects that are currently under preclinical development or testing
in clinical trials, or approved for medical use.
Mesenchymal Stem Cell-Derived Extracellular Vesicles for Corneal Wound Repair
