Endogenous neurogenesis replaces oligodendrocytes and astrocytes after primate spinal cord injury.
Neurogenesis has been described in various regions of the CNS throughout life. We examined the extent of natural cell division and replacement from 7 weeks to 7 months after cervical spinal cord injury in four adult rhesus monkeys. Bromodeoxyuridine (BrdU) injections revealed an increase of >80-fold in the number of newly divided cells in the primate spinal cord after injury, with an average of 725,000 BrdU-labeled cells identified per monkey in the immediate injury zone. By 7 months after injury, 15% of these new cells expressed mature markers of oligodendrocytes and 12% expressed mature astrocytic markers. Newly born oligodendrocytes were present in zones of injury-induced demyelination and appeared to ensheath or remyelinate host axons. Thus, cell replacement is an extensive natural compensatory response to injury in the primate spinal cord that contributes to neural repair and is a potential target for therapeutic enhancement.
Department of Neurosciences, University of California, San Diego, La Jolla, California 92093-0626, USA.
Hong
H
Yang
Paul
P
Lu
Heather M
HM
McKay
Tim
T
Bernot
Hans
H
Keirstead
Oswald
O
Steward
Fred H
FH
Gage
V Reggie
VR
Edgerton
Mark H
MH
Tuszynski
D000818:Animals; D001253:Astrocytes / Q000473:pathology*; D002454:Cell Differentiation; D002455:Cell Division; D049109:Cell Proliferation; D008253:Macaca mulatta; D008297:Male; D009416:Nerve Regeneration; D009473:Neuronal Plasticity; D009474:Neurons / Q000473:pathology*; D009836:Oligodendroglia / Q000473:pathology*; D013116:Spinal Cord / Q000473:pathology* / Q000503:physiopathology; D013119:Spinal Cord Injuries / Q000473:pathology* / Q000503:physiopathology