In vitro and in situ properties of canine neural precursor cells with respect to transplantation potential

Neurodegenerative diseases represent a broad spectrum of genetic and acquired processes that would benefit from CNS transplantation therapy. Mucopolysaccharidosis VII (MPS VII) is a genetic disease with neurodegeneration caused by beta-glucuronidase (GUSB) enzyme deficiency. The existence of animal homologues of human MPS VII make this disease a valuable model for transplantation therapy. The studies described herein focused upon the characterization of canine neural precursor cells (CNPCs) for CNS transplantation therapy in an animal model of MPS VII.; Canine NPCs were isolated from three neurogenic regions of the postnatal brain: the olfactory bulb, cerebellum and subventricular zone (SVZ). The growth, expansion, and multipotency of CNPCs from unaffected and MPS VII dogs were compared. There were no differences attributable to CNPC genotype. Cerebellar-derived CNPCs grew more slowly than those from other brain regions. Independent of genotype or region, undifferentiated CNPCs were immunopositive for nestin and glial fibrillary acidic protein (GFAP), and could be differentiated into neurons, astrocytes and oligodendrocytes.; Neurogenic regions within the canine brain were evaluated for two candidate NPC cell surface markers, CD15 and CD133. We evaluated the immunophenotype of cells in the ventricular/subventricular zone and the cerebellum. CD15 immunoreactivity in the postnatal cerebellum was present in white matter tracts of folia. The embryonic ventricular zone and postnatal SVZ stained positively for CD15, but were immunonegative for CD133. The proportion of CD15-positive cells in the canine SVZ was 6.6 +/- 2.2%.; Canine NPCs were efficiently transduced with retroviral vectors containing the human GUSB gene and promoter. Xenograft transplants of transduced CNPCs into neonatal SCID mice showed sparse but consistent GUSB-positive cell engraftment up to six weeks post-transplantation, especially in white matter tracts. In allograft transplants, small numbers of GUSB-positive cells were detected up to 4 weeks post-transplantation. At 2 weeks post-transplantation, small numbers of nestin-positive and GFAP-positive graft cells were identified, but no graft cells stained with neuronal markers.; The data describe a population of cells in the postnatal dog that possesses characteristics of NPCs. It is hoped that CNPC characterization will afford a valuable model of therapeutic cellular transplantation in a large animal model of genetic neurodegenerative disease.