title: Assessment of hippocampal adeno-associated viral vector gene delivery via frameless stereotaxis in a nonhuman primate.
abstract: OBJECTIVE
  Expression of the neuropeptide galanin in hippocampal neurons reduces seizures in the kainic acid rodent model of epilepsy. In order to translate these findings into a human clinical trial, the safety and feasibility of hippocampal adeno-associated viral (AAV) vector expression must be demonstrated in a nonhuman primate model.
  
  
  METHODS
  The Stealth Frameless Stereotactic System and Navigus Biopsy Appliance (Medtronic) were used to inject self-complementary AAV2 carrying the gene for green fluorescent protein (GFP) into monkey hippocampi. Using a single occipital trajectory per side (n = 8 trajectories), multiple injections spaced by 5 mm were delivered to each hippocampus.
  
  
  RESULTS
  GFP was expressed in both neuronal and glial cells. Injections led to nonhomogeneous gene expression, suggesting closer spacing of injections may lead to more gene expression. Increasing injection volumes entailed a general increase in volume of expression, but there was no overlap of expression within the 5-mm injection interval. Efforts to avoid the occipital horn failed to prevent leaking of vector into the ventricle, and resulted in deviation of the trajectory at proximal points from the hippocampus.
  
  
  CONCLUSIONS
  Using the occipital approach, adequate cannulation of the monkey hippocampus will require transventricular trajectories.
authors.affiliation: Department of Neurosurgery, Emory University School of Medicine, Atlanta, GA 30322, USA.
authors.forename: Cary H
authors.initials: CH
authors.lastname: Leung
authors.forename: Michele A
authors.initials: MA
authors.lastname: Kliem
authors.forename: Brenten L
authors.initials: BL
authors.lastname: Heeke
authors.forename: Scott W J
authors.initials: SW
authors.lastname: McPhee
authors.forename: Thais
authors.initials: T
authors.lastname: Federici
authors.forename: Brooke R
authors.initials: BR
authors.lastname: Snyder
authors.forename: Nicholas M
authors.initials: NM
authors.lastname: Boulis
mesh_terms: D000818:Animals; D000229:Dependovirus / Q000235:genetics*; D018014:Gene Transfer Techniques / Q000295:instrumentation; D005822:Genetic Vectors / Q000008:administration & dosage / Q000235:genetics*; D049452:Green Fluorescent Proteins / Q000008:administration & dosage / Q000235:genetics; D006624:Hippocampus / Q000378:metabolism / Q000821:virology; D008253:Macaca mulatta; D008297:Male; D038361:Neuronavigation / Q000379:methods*
chemical_list: D049452:Green Fluorescent Proteins