Background: Corneal alkali injuries are considered a common ophthalmologic emergency with many serious
complications. Adipose Tissue-Derived Stem Cells (ADSCs) and Mesenchymal Stem Cells derived Exosomes
(MSCs-EX) are promising approaches in regenerative therapies.
Objective: The aim of this study is to evaluate the efficacy of ADSCs versus MSCs-EX on experimentally alkaliinduced corneal injuries in rats.
Materials and Methods: 40 adult male albino rats were divided into four groups, that is, Group I: control rats,
Group II: alkali burn rats, Group III: ADSCs treated rats after corneal alkali burn, Group IV: MSCs-EX treated rats after
corneal alkali burn. Cornea specimens were taken and processed for histological examination.
Results: Group II showed obvious changes such as erosion with focal loss of some superficial epithelial cells,
while the basal and intermediate epithelial cell layers had vacuolated cytoplasm with pyknotic nuclei. The substantia
propria contained irregularly arranged collagen fibers with wide spacing, keratocytes, and congested blood vessels.
Descemet's membrane appeared thin and degenerated with focal loss of some endothelial cells. Ultrastructural
examination showed degenerated apical squamous cells with loss of microvilli on their free surface. The basal cells
had irregular contour with widening of intracellular space between cells with multiple cytoplasmic vacuoles. The
substantia propria showed disorganized collagen fibers with degenerated keratocytes and mononuclear cellular
infiltration. Groups III and IV showed improvement of the histological and electron microscopic changes described in
group II.
Conclusion: ADSCs and MSCs-EX can improve corneal alkali burn injuries and prevent their complications.
Exosomes are a more promising therapeutic approach.