title: Midbrain injection of recombinant adeno-associated virus encoding rat glial cell line-derived neurotrophic factor protects nigral neurons in a progressive 6-hydroxydopamine-induced degeneration model of Parkinson's disease in rats.
abstract: A recombinant adeno-associated virus (rAAV) vector capable of infecting cells and expressing rat glial cell line-derived neurotrophic factor (rGDNF), a putative central nervous system dopaminergic survival factor, under the control of a potent cytomegalovirus (CMV) immediate/early promoter (AAV-MD-rGDNF) was constructed. Two experiments were performed to evaluate the time course of expression of rAAV-mediated GDNF protein expression and to test the vector in an animal model of Parkinson's disease. To evaluate the ability of rAAV-rGDNF to protect nigral dopaminergic neurons in the progressive Sauer and Oertel 6-hydroxydopamine (6-OHDA) lesion model, rats received perinigral injections of either rAAV-rGDNF virus or rAAV-lacZ control virus 3 weeks prior to a striatal 6-OHDA lesion and were sacrificed 4 weeks after 6-OHDA. Cell counts of back-labeled fluorogold-positive neurons in the substantia nigra revealed that rAAV-MD-rGDNF protected a significant number of cells when compared with cell counts of rAAV-CMV-lacZ-injected rats (94% vs. 51%, respectively). In close agreement, 85% of tyrosine hydroxylase-positive cells remained in the nigral rAAV-MD-rGDNF group vs. only 49% in the lacZ group. A separate group of rats were given identical perinigral virus injections and were sacrificed at 3 and 10 weeks after surgery. Nigral GDNF protein expression remained relatively stable over the 10 weeks investigated. These data indicate that the use of rAAV, a noncytopathic viral vector, can promote delivery of functional levels of GDNF in a degenerative model of Parkinson's disease.
authors.affiliation: Department of Gene Therapy Applications, Cell Genesys Inc., 342 Lakeside Drive, Foster City, CA 94404, USA. rmandel@hisemail.com
authors.forename: R J
authors.initials: RJ
authors.lastname: Mandel
authors.forename: S K
authors.initials: SK
authors.lastname: Spratt
authors.forename: R O
authors.initials: RO
authors.lastname: Snyder
authors.forename: S E
authors.initials: SE
authors.lastname: Leff
mesh_terms: D000818:Animals; D000229:Dependovirus / Q000235:genetics; D004195:Disease Models, Animal; D015870:Gene Expression; D015316:Genetic Therapy / Q000379:methods*; D005822:Genetic Vectors; D051100:Glial Cell Line-Derived Neurotrophic Factor; D006367:HeLa Cells; D006801:Humans; D009410:Nerve Degeneration; D009414:Nerve Growth Factors; D009419:Nerve Tissue Proteins / Q000235:genetics* / Q000378:metabolism; D016627:Oxidopamine / Q000633:toxicity; D010302:Parkinson Disease, Secondary / Q000139:chemically induced / Q000473:pathology / Q000628:therapy*; D051381:Rats; D011916:Rats, Inbred F344; D011995:Recombination, Genetic; D013378:Substantia Nigra / Q000473:pathology
chemical_list: C495039:GDNF protein, human; C495041:Gdnf protein, rat; D051100:Glial Cell Line-Derived Neurotrophic Factor; D009414:Nerve Growth Factors; D009419:Nerve Tissue Proteins; D016627:Oxidopamine