title: Stereotactic transplantation of a dopamine-producing capsule into the striatum for treatment of Parkinson disease: a preclinical primate study.
abstract: OBJECTIVE
  The PC12 cells are well known for their ability to secrete dopamine and levodopa. In multiple animal mode encapsulated PC12 cells have been shown to ameliorate parkinsonian symptoms when transplanted into the striatum; technique is expected to be effective clinically as well. The present study was performed using nonhuman primates to ensure that the transplantation of encapsulated PC12 cells is likely to be both safe and effective in human clinical trials.
  
  
  METHODS
  Unencapsulated or encapsulated PC12 cells were implanted into the brains of Japanese monkeys (Macaca fuscata). Histological and immunocytochemical analyses were performed 1, 2, 4, and 8 weeks posttransplantation on the unencapsulated cells and 2, 4, and 8 weeks after transplantation on the encapsulated cells. The survival of the PC12 cells inside the capsule was determined by measuring the amounts of dopamine and levodopa released from the capsules a removal from the striatum. Magnetic resonance imaging was performed in both unencapsulated and encapsulated PC12 cell-grafted groups. Due to the immunological reaction of the host brain no unencapsulated PC12 cells remained in the grafted area 8 weeks after transplantation. On the contrary, encapsulated PC12 cells retrieved from the host brain continued to release dopamine and levodopa even 8 weeks after implantation. The host's reaction to the PC12-loaded capsule was much weaker than that to the unencapsulated PC12 cells.
  
  
  CONCLUSIONS
  These results suggest that the transplantation of encapsulated PC12 cells could be a safe and effective treatment modality for Parkinson disease in human patients.
authors.affiliation: Department of Neurological Surgery, Okayama University Graduate School of Medicine and Dentistry, Okayama, Japan.
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Yoshida
authors.forename: Isao
authors.initials: I
authors.lastname: Date
authors.forename: Tetsuro
authors.initials: T
authors.lastname: Shingo
authors.forename: Kenjiro
authors.initials: K
authors.lastname: Fujiwara
authors.forename: Kazuki
authors.initials: K
authors.lastname: Kobayashi
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Miyoshi
authors.forename: Takashi
authors.initials: T
authors.lastname: Ohmoto
mesh_terms: D000818:Animals; D016380:Brain Tissue Transplantation / Q000295:instrumentation*; D002851:Chromatography, High Pressure Liquid; D003342:Corpus Striatum / Q000378:metabolism / Q000473:pathology / Q000637:transplantation*; D004298:Dopamine / Q000378:metabolism*; D007150:Immunohistochemistry; D007980:Levodopa / Q000378:metabolism; D008251:Macaca; D008279:Magnetic Resonance Imaging; D016716:PC12 Cells / Q000378:metabolism / Q000637:transplantation*; D010300:Parkinson Disease / Q000378:metabolism / Q000473:pathology / Q000601:surgery*; D051381:Rats; D013238:Stereotaxic Techniques / Q000295:instrumentation*
chemical_list: D007980:Levodopa; D004298:Dopamine