Abstract
Abstract: :
Purpose: To assess the ability of rat embryonic spinal cord stem cells (SCSCs) to survive, migrate and differentiate in mechanically damaged adult rat retinas. Methods: SCSCs were isolated from 13-day fetal rat spinal cord and cultured for up to one year in serum free medium with bFGF and EGF. One eye of each adult Wistar rat (n=23) received a retinal scratch. The injured eye received only DiI-labeled SCSC. The contralateral uninjured eye received either SCSC or buffer. At intervals up to 5 weeks, retinas were removed and evaluated by fluorescence microscopy. Results: In vitro, SCSC cultured with EGF and bFGF exhibited continuous proliferation and neurosphere formation. Differentiation to astrocytes, neurons or oligodendrocytes was induced by incubation in medium with serum, retinoic acid + bFGF, or no growth factors, respectively. Following injection of DiI-labeled SCSC into the vitreous, labeled cells were identified in all injured retinas. Lateral migration of cells within the retina was apparent. Di-I labeled SCSC were present in several retinal layers, including the gangion cell and inner nuclear layers. In control, non-injured retinas, DiI-labeled SCSCs were observed only on the retinal surface. Morphological evidence of SCSC differentiation in injured retinas was evident at 3 weeks. Neuron-like cells with 50-100 um processes oriented towards the optic nerve were observed. Conclusion: Rat embryonic SCSCs injected into the vitreous can colonize injured retinas. Some of these cells appear to have the capacity to migrate and differentiate, suggesting SCSCs have potential for replacement therapy in optic neuropathies.
Keywords: 607 transplantation • 554 retina • 456 lesion study