Lineage negative (Lin -) hematopoietic stem cells (HSC) administered to the vitreous of models with retinal degeneration (with associated outer vascular layer and photoreceptor loss by P21) completely rescues the degenerating retinal vasculature. The same model had one eye (image right) treated on six days after birth with Lin+ HSC and the other (image left) with Lin- HSC. At two months of age, the eyes were examined for blood vessels (green) and nuclei (red). Not only are all three vascular layers preserved in the treated eye, but the nuclear layers (cells responsible for vision) are also much better preserved. (GC, ganglion cell layer; INL, inner nuclear layer; ONL, outer nuclear layer).