The present invention is directed to methods of repairing damaged or diseased, specialized or differentiated tissue in mature animals, particularly neuronal tissue such as retinas. In particular, the invention relates to transplantation of adult, hippocampus-derived progenitor cells into a selected neural tissue site of a recipient. These cells can functionally integrate into mature and immature neural tissue. The invention encompasses, in one aspect, repopulating a retina of a dystrophic animal with neurons, by injecting clonally derived, adult central nervous system derived stem cells (ACSC) derived from a healthy donor animal into an eye of the dystrophic recipient. Herein disclosed is the first successful and stable integration of clonally derived ACSC into same-species but different strain recipients (e. g., Fischer rat-derived adult hippocampal derived progenitor cells (AHPCs) into dystrophic RCS rats). Surprisingly, AHPCs were also found to integrate successfully into a xenogeneic recipient (e.g., rat AHPCs into the retina of dystropic rd-I mice).
Method of isolating adult mammalian CNS-derived progenitor stem cells using density gradient centrifugation