Towards a Non-Human Primate Model of Alpha-Synucleinopathy for Development of Therapeutics for Parkinson's Disease: Optimization of AAV1/2 Delivery Parameters to Drive Sustained Expression of Alpha Synuclein and Dopaminergic Degeneration in Macaque

PLoS One. 2016 Nov 30;11(11):e0167235. doi: 10.1371/journal.pone.0167235. eCollection 2016.

Abstract

Recent failures in clinical trials for disease modification in Parkinson's disease have highlighted the need for a non-human primate model of the synucleinopathy underpinning dopaminergic neuron degeneration. The present study was defined to begin the development of such a model in cynomolgus macaque. We have validated surgical and vector parameters to define a means to provide a robust over-expression of alpha-synuclein which is associated with Lewy-like pathology and robust degeneration of the nigrostriatal pathway. Thus, an AAV1/2 vector incorporating strong transcription and transduction regulatory elements was used to deliver the gene for the human A53T mutation of alpha-synuclein. When injected into 4 sites within each substantia nigra (7 μl per site, 1.7 x 1012 gp/ml), this vector provided expression lasting at least 4 months, and a 50% loss of nigral dopaminergic neurons and a 60% reduction in striatal dopamine. Further studies will be required to develop this methodology into a validated model of value as a drug development platform.

MeSH terms

  • Animals
  • Dependovirus / genetics*
  • Disease Models, Animal
  • Dopaminergic Neurons / pathology*
  • Female
  • Gene Expression
  • Genetic Therapy / methods*
  • Genetic Vectors / genetics
  • Humans
  • Macaca
  • Neostriatum / metabolism
  • Parkinson Disease / genetics
  • Parkinson Disease / metabolism
  • Parkinson Disease / pathology
  • Parkinson Disease / therapy*
  • alpha-Synuclein / genetics*

Substances

  • alpha-Synuclein

Grants and funding

Funding was provided for by Atuka Inc. and the Krembil Foundation. There was no additional external funding received for this study. The funder (Atuka Inc.) provided support in the form of consultancies for authors [JBK, THJ, JMB], but did not have any additional role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. The specific roles of these authors are articulated in the 'author contributions' section.