title: Harvested human neurons engineered as live nervous tissue constructs: implications for transplantation. Laboratory investigation.
abstract: OBJECTIVE
  Although neuron transplantation to repair the nervous system has shown promise in animal models, there are few practical sources of viable neurons for clinical application and insufficient approaches to bridge extensive nerve damage in patients. Therefore, the authors sought a clinically relevant source of neurons that could be engineered into transplantable nervous tissue constructs. The authors chose to evaluate human dorsal root ganglion (DRG) neurons due to their robustness in culture.
  
  
  METHODS
  Cervical DRGs were harvested from 16 live patients following elective ganglionectomies, and thoracic DRGs were harvested from 4 organ donor patients. Following harvest, the DRGs were digested in a dispase-collagenase treatment to dissociate neurons for culture. In addition, dissociated human DRG neurons were placed in a specially designed axon expansion chamber that induces continuous mechanical tension on axon fascicles spanning 2 populations of neurons originally plated approximately 100 microm apart.
  
  
  RESULTS
  The adult human DRG neurons, positively identified by neuronal markers, survived at least 3 months in culture while maintaining the ability to generate action potentials. Stretch-growth of axon fascicles in the expansion chamber occurred at the rate of 1 mm/day to a length of 1 cm, creating the first engineered living human nervous tissue constructs.
  
  
  CONCLUSIONS
  These data demonstrate the promise of adult human DRG neurons as an alternative transplant material due to their availability, viability, and capacity to be engineered. Also, these data show the feasibility of harvesting DRGs from living patients as a source of neurons for autologous transplant as well as from organ donors to serve as an allograft source of neurons.
authors.affiliation: Department of Neurosurgery, University of Rochester Medical Center, Rochester, New York, USA.
authors.forename: Jason H
authors.initials: JH
authors.lastname: Huang
authors.forename: Eric L
authors.initials: EL
authors.lastname: Zager
authors.forename: Jun
authors.initials: J
authors.lastname: Zhang
authors.forename: Robert F
authors.initials: RF
authors.lastname: Groff
authors.forename: Bryan J
authors.initials: BJ
authors.lastname: Pfister
authors.forename: Akiva S
authors.initials: AS
authors.lastname: Cohen
authors.forename: M Sean
authors.initials: MS
authors.lastname: Grady
authors.forename: Eileen
authors.initials: E
authors.lastname: Maloney-Wilensky
authors.forename: Douglas H
authors.initials: DH
authors.lastname: Smith
mesh_terms: D000200:Action Potentials / Q000502:physiology; D000328:Adult; D001369:Axons / Q000502:physiology / Q000648:ultrastructure; D018929:Cell Culture Techniques; D002470:Cell Survival; D002675:Child, Preschool; D005240:Feasibility Studies; D005260:Female; D005727:Ganglia, Spinal / Q000166:cytology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009474:Neurons / Q000166:cytology* / Q000502:physiology / Q000637:transplantation; D013314:Stress, Mechanical; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds; D020858:Tissue and Organ Harvesting