Reestablishment of damaged adult motor pathways by grafted embryonic cortical neurons

Nat Neurosci. 2007 Oct;10(10):1294-9. doi: 10.1038/nn1970. Epub 2007 Sep 2.

Abstract

Damage to the adult motor cortex leads to severe and frequently irreversible deficits in motor function. Transplantation of embryonic cortical neurons into the damaged adult motor cortex was previously shown to induce partial recovery, but reports on graft efferents have varied from no efferent projections to sparse innervation. Here, we grafted embryonic cortical tissue from transgenic mice overexpressing a green fluorescent protein into the damaged motor cortex of adult mice. Grafted neurons developed efferent projections to appropriate cortical and subcortical host targets, including the thalamus and spinal cord. These projections were not a result of cell fusion between the transplant and the host neurons. Host and transplanted neurons formed synaptic contacts and numerous graft efferents were myelinated. These findings demonstrate that there is substantial anatomical reestablishment of cortical circuitry following embryonic cortex grafting into the adult brain. They suggest that there is an unsuspected potential for neural cell transplantation to promote reconstruction after brain injury.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Brain Injuries* / pathology
  • Brain Injuries* / physiopathology
  • Brain Injuries* / surgery
  • Brain Tissue Transplantation / methods
  • Doublecortin Domain Proteins
  • Embryo, Mammalian
  • Green Fluorescent Proteins / genetics
  • In Situ Hybridization, Fluorescence / methods
  • Mice
  • Mice, Inbred C57BL
  • Mice, Transgenic
  • Microscopy, Immunoelectron / methods
  • Microtubule-Associated Proteins / metabolism
  • Motor Cortex / cytology*
  • Motor Cortex / surgery*
  • Nerve Regeneration / physiology*
  • Neural Pathways / physiology
  • Neurons / metabolism
  • Neurons / transplantation*
  • Neurons / ultrastructure
  • Neuropeptides / metabolism

Substances

  • Doublecortin Domain Proteins
  • Microtubule-Associated Proteins
  • Neuropeptides
  • Green Fluorescent Proteins