title: Transplanted embryonic neurons integrate into adult neocortical circuits.
abstract: The ability of the adult mammalian brain to compensate for neuronal loss caused by injury or disease is very limited. Transplantation aims to replace lost neurons, but the extent to which new neurons can integrate into existing circuits is unknown. Here, using chronic in vivo two-photon imaging, we show that embryonic neurons transplanted into the visual cortex of adult mice mature into bona fide pyramidal cells with selective pruning of basal dendrites, achieving adult-like densities of dendritic spines and axonal boutons within 4-8 weeks. Monosynaptic tracing experiments reveal that grafted neurons receive area-specific, afferent inputs matching those of pyramidal neurons in the normal visual cortex, including topographically organized geniculo-cortical connections. Furthermore, stimulus-selective responses refine over the course of many weeks and finally become indistinguishable from those of host neurons. Thus, grafted neurons can integrate with great specificity into neocortical circuits that normally never incorporate new neurons in the adult brain.
authors: Max Planck Institute of Neurobiology, D-82152 Martinsried, Germany.
authors: Susanne
authors: S
authors: Falkner
authors: Physiological Genomics, Biomedical Center, Ludwig-Maximilians University Munich, D-82152 Planegg, Germany.|Institute of Stem Cell Research, Helmholtz Center Munich, German Research Center for Environmental Health, D-85764 Neuherberg, Germany.
authors: Sofia
authors: S
authors: Grade
authors: Physiological Genomics, Biomedical Center, Ludwig-Maximilians University Munich, D-82152 Planegg, Germany.|Institute of Stem Cell Research, Helmholtz Center Munich, German Research Center for Environmental Health, D-85764 Neuherberg, Germany.|SYNERGY, Excellence Cluster of Systems Neurology, Biomedical Center, Ludwig-Maximilians University Munich, D-82152 Planegg , Germany.
authors: Leda
authors: L
authors: Dimou
authors: Max von Pettenkofer Institute and Gene Center, Ludwig-Maximilians University Munich, D-81377 Munich, Germany.
authors: Karl-Klaus
authors: KK
authors: Conzelmann
authors: Max Planck Institute of Neurobiology, D-82152 Martinsried, Germany.
authors: Tobias
authors: T
authors: Bonhoeffer
authors: Physiological Genomics, Biomedical Center, Ludwig-Maximilians University Munich, D-82152 Planegg, Germany.|Institute of Stem Cell Research, Helmholtz Center Munich, German Research Center for Environmental Health, D-85764 Neuherberg, Germany.|SYNERGY, Excellence Cluster of Systems Neurology, Biomedical Center, Ludwig-Maximilians University Munich, D-82152 Planegg , Germany.
authors: Magdalena
authors: M
authors: Götz
authors: Max Planck Institute of Neurobiology, D-82152 Martinsried, Germany.
authors: Mark
authors: M
authors: Hübener
mesh_terms: D000344:Afferent Pathways; D000818:Animals; D001369:Axons / Q000378:metabolism; D002454:Cell Differentiation; D058948:Cell Tracking; D049229:Dendritic Spines / Q000378:metabolism; D004525:Efferent Pathways; D004622:Embryo, Mammalian / Q000166:cytology*; D051379:Mice; D019579:Neocortex / Q000166:cytology* / Q000502:physiology; D009434:Neural Pathways; D009474:Neurons / Q000166:cytology / Q000502:physiology* / Q000637:transplantation*; D017729:Presynaptic Terminals / Q000378:metabolism; D017966:Pyramidal Cells / Q000166:cytology / Q000502:physiology; D014793:Visual Cortex / Q000166:cytology* / Q000502:physiology