Mouse Degenerating Optic Axons Survived by Human Embryonic Stem Cell-Derived Neural Progenitor Cells.

Objective: Any damage to the optic nerve can potentially lead to degeneration of non-regenerating axons and ultimately death of retinal ganglion cells (RGCs) that in most cases, are not curable by surgery or medication. Neuroprotective functions of different types of stem cells in the nervous system have been evaluated in many studies investigating the effectiveness of these cells in various retinal disease models. Neural progenitor cells (NPCs) secrete an assortment of trophic factors that are vital to the protection of the visual system. We aimed to assess the therapeutic potentials of NPCs in an ONC mouse model. Materials and Methods: In this experimental study, NPCs were produced using noggin and retinoic acid from human embryonic stem cells (hESCs). Fifty mice were divided into the following three groups: i. Intact , ii. Vehicle [optic nerve crush+Hank's balanced salt solution (HBSS)], and iii. Treatment (optic nerve crush+NPCs). The visual behavior of the mice was examined using the Visual Cliff test, and in terms of RGC numbers, they were assessed by Brn3a immunostaining and retrograde tracing using DiI injection. Results: Intravenous injection of 50,000 NPCs through visual cliff did not produce any visual improvement. However, our data suggest that the RGCs protection was more than two-times in NPCs compared to the vehicle group as examined by Brn3a staining and retrograde tracing. Conclusion: Our study indicated that intravenous injection of NPCs could protect RGCs probably mediated by trophic factors. Due to this ability and good manufacturing practices (GMP) grade production feasibility, NPCs may be used for optic nerve protection.