title: Retinal neural progenitors express topographic map markers.
abstract: Transplantation of neural stem cells for replacing neurons after neurodegeneration requires that the transplanted stem cells accurately reestablish the lost neural circuits in order to restore function. Retinal ganglion cell axons project to visual centers of the brain forming circuits in precise topographic order. In chick, dorsal retinal neurons project to ventral optic tectum, ventral neurons to dorsal tectum, anterior neurons to posterior tectum and posterior neurons to anterior tectum; forming a continuous point-to-point map of retinal cell position in the tectal projection. We found that when stem cells derived from ventral retina were implanted in dorsal host retina, the stem cells that became ganglion cells projected to dorsal tectum, appropriate for their site of origin in retina but not appropriate for their site of implant in retina. This led us to ask if retinal progenitors exhibit topographic markers of cell position in retina. Indeed, retinal neural progenitors express topographic markers: dorsal stem cells expressed more Ephrin B2 than ventral stem cells and, conversely, ventral stem cells expressed more Pax-2 and Ventroptin than dorsal stem cells. The fact that neural progenitors express topographic markers has pertinent implications in using neural stem cells in cell replacement therapy for replacing projecting neurons that express topographic order, e.g., analogous neurons of the visual, auditory, somatosensory and motor systems.
authors.affiliation: Department of Neurology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; VAMHCS, Baltimore, MD 21201, USA. JGoolsby@paragonbioservices.com
authors.forename: James
authors.initials: J
authors.lastname: Goolsby
authors.forename: Michael
authors.initials: M
authors.lastname: Atamas
authors.forename: Sarah
authors.initials: S
authors.lastname: Rollor
authors.forename: David
authors.initials: D
authors.lastname: Asanuma
authors.forename: Rosemary
authors.initials: R
authors.lastname: Schuh
authors.forename: Tapas
authors.initials: T
authors.lastname: Makar
authors.forename: Paul S
authors.initials: PS
authors.lastname: Fishman
authors.forename: Christopher T
authors.initials: CT
authors.lastname: Bever
authors.forename: David
authors.initials: D
authors.lastname: Trisler
mesh_terms: D000818:Animals; D001483:Base Sequence; D002642:Chick Embryo; D017931:DNA Primers; D006801:Humans; D012160:Retina / Q000166:cytology*; D013234:Stem Cells / Q000166:cytology*
chemical_list: D017931:DNA Primers