Pleiotrophin over-expression after intrastriatal and intranigral administration of a recombinant adenoviral vector containing human pleiotrophin cDNA

TARAVINI IR; CHERTOFF M; CAFFERATA E; MURER MG; PITOSSI F; GERSHANIK O

Estambul, Turquía

Congreso; 11th International Congress of Parkinson's Disease and Movement Disorders; 2007

The Movement Disorder Society

Background: Clinical signs of Parkinson’s disease (PD) are not evident until 50% of SNpc neurons have died and up to 90% dopaminergic neurons die despite treatment. Therefore, there is strong interest in research on PD cause and on the development of novel therapeutic strategies aimed at preventing the degenerative process or restoring the structure and function of the damaged nigroestriatal system. PTN is a neurite outgrowth-promoting factor expressed during embryonic and early postnatal development. Furthermore, it is believed that PTN promotes survival and differentiation of dopamine neurons from embryonic stem cells. Recently, we found an over-expression of PTN in the striatum of adult rats with a unilateral 6-OHDA lesion of the nigrostriatal tract chronically treated with levodopa. Methods: We generated a recombinant adenovirus that expresses PTN (AdPTN). The human PTN cDNA was cloned into a shuttle vector with a human cytomegalovirus promoter and cotransfected into HEK293 cells with a plasmid containing E1-E3-deleted type 5 adenoviral genome using a calcium phosphate coprecipitation method. Stocks of AdPTN were obtained from large-scale preparations in 293 cells and then purified by CsCl gradients. Final titer: 2.15x109 pfu/µl. AdPTN was injected in the striatum or SNpc of adult rats (1x107 pfu/μl/rat). Seven days after that, PTN was detected by immunohistochemistry on brain tissue sections. Results: In control animals injected with an adenovirus expressing β-galactosidase, PTN expression was restricted to striatal interneurons and a few neurons in the SNpc. AdPTN was effective in inducing PTN over-expression. Preliminary analysis suggests that both glia and neurons were over-expressing PTN. Conclusions: We have constructed a PTN-containing adenovirus which successfully over-expressed PTN in vivo. This adenovirus will be useful to increase our understanding of the functions of PTN in the adult nigrostriatal innervation, and in particular, help us to determine the potential of PTN as a preventive or restorative therapy for PD.