Effect of human cord blood-derived stem cells on induced diabetic retinopathy in adult albino rat: histological and immunohistochemical study

Diabetic retinopathy is a leading cause of blindness in adults. Recent developments in stem cell field have widened the prospects of applying cell-based therapies to regenerate ocular tissues. This study was done to explore the potential effect of human cord blood-derived stem cells on induced diabetic retinopathy in adult albino rats. This study was performed on 26 adult male albino rats. Animals were randomly divided into four groups. Group I [control group]: five control animals each received single intraperitoneal injection of citrate buffer. Group II: seven animals in whom diabetes was induced by single intraperitoneal injection of streptolotocin and animals were killed 4 weeks later. Group III: seven animals in whom diabetes was induced the same way as in group II and animals were killed 8 weeks later. Group IV: seven animals with diabetes were injected with ferrous oxide-labeled cord blood-derived stem cells 4 weeks after induction of diabetes and were killed 4 weeks after stem cell injection, All sections from retina of all groups were subjected to Haematoxylin and eosin, Prussian blue staining and CD34 immunohistochemistry. Statistical analysis was done to measure the mean number of ganglion cell nuclei and the wide clear areas around them. Groups II and III showed progressive histological changes of diabetic retinopathy. Group IV exhibited a significant increase in the number of ganglion cells with less clear areas compared with group III. Moreover, cells positive for Prussian blue and CD34 were detected in different retinal layers of group IV. Human cord blood-derived stem cells injected into rats with diabetic retinopathy contributed to restoration of ganglion cell layer and vascular repair, which may postulate a potential therapeutic intervention for diabetic retinopathy