title: Recombinant Adeno Associated Viral (AAV) vector type 9 delivery of Ex1-Q138-mutant huntingtin in the rat striatum as a short-time model for in vivo studies in drug discovery.
abstract: Huntington's disease (HD) is an inherited neurodegenerative disorder characterized by dyskinesia, cognitive impairment and emotional disturbances, presenting progressive neurodegeneration in the striatum and intracellular mutant Huntingtin (mHTT) aggregates in various areas of the brain. Recombinant Adeno Associated Viral (rAAV) vectors have been successfully used to transfer foreign genes to the brain of adult animals. In the present study we report a novel in vivo rat HD model obtained by stereotaxic injection of rAAV serotype2/9 containing Exon1-Q138 mHTT (Q138) and Exon1-Q17 wild type HTT (Q17; control), respectively in the right and in the left striatum, and expressed as C-terminal GFP fusions to facilitate detection of infected cells and aggregate production. Immunohistochemical analysis of brain slices from animals sacrificed twenty-one days after viral infection showed that Q138 injection resulted in robust formation of GFP-positive aggregates in the striatum, increased GFAP and microglial activation and neurodegeneration, with little evidence of any of these events in contralateral tissue infected with wild type (Q17) expressing construct. Differences in the relative metabolite concentrations (N-Acetyl Aspartate/Creatine and Myo-Inositol/Creatine) were observed by H1 MR Spectroscopy. By quantitative RT-PCR we also demonstrated that mHTT induced changes in the expression of genes previously shown to be altered in other rodent HD models. Importantly, administration of reference compounds previously shown to ameliorate the aggregation and neurodegeneration phenotypes in preclinical HD models was demonstrated to revert the mutant HTT-dependent effects in our model. In conclusion, the AAV2/9-Q138/Q17 exon 1 HTT stereotaxic injection represents a useful first-line in vivo preclinical model for studying the biology of mutant HTT exon 1 in the striatum and to provide early evidence of efficacy of therapeutic approaches.
authors.affiliation: Siena Biotech S.p.A, Strada del Petriccio e Belriguardo, 35 53100 Siena, (Italy).
authors.forename: Ilaria
authors.initials: I
authors.lastname: Ceccarelli
authors.affiliation: Siena Biotech S.p.A, Strada del Petriccio e Belriguardo, 35 53100 Siena, (Italy).
authors.forename: Pasquale
authors.initials: P
authors.lastname: Fiengo
authors.affiliation: Siena Biotech S.p.A, Strada del Petriccio e Belriguardo, 35 53100 Siena, (Italy).
authors.forename: Rosaria
authors.initials: R
authors.lastname: Remelli
authors.affiliation: Siena Biotech S.p.A, Strada del Petriccio e Belriguardo, 35 53100 Siena, (Italy).
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Miragliotta
authors.affiliation: Siena Biotech S.p.A, Strada del Petriccio e Belriguardo, 35 53100 Siena, (Italy).
authors.forename: Lara
authors.initials: L
authors.lastname: Rossini
authors.affiliation: Siena Biotech S.p.A, Strada del Petriccio e Belriguardo, 35 53100 Siena, (Italy).
authors.forename: Irene
authors.initials: I
authors.lastname: Biotti
authors.affiliation: Siena Biotech S.p.A, Strada del Petriccio e Belriguardo, 35 53100 Siena, (Italy).
authors.forename: Alessandra
authors.initials: A
authors.lastname: Cappelli
authors.affiliation: Siena Biotech S.p.A, Strada del Petriccio e Belriguardo, 35 53100 Siena, (Italy).
authors.forename: Lara
authors.initials: L
authors.lastname: Petricca
authors.affiliation: Siena Biotech S.p.A, Strada del Petriccio e Belriguardo, 35 53100 Siena, (Italy).
authors.forename: Salvatore
authors.initials: S
authors.lastname: La Rosa
authors.affiliation: Siena Biotech S.p.A, Strada del Petriccio e Belriguardo, 35 53100 Siena, (Italy).
authors.forename: Andrea
authors.initials: A
authors.lastname: Caricasole
authors.affiliation: Siena Biotech S.p.A, Strada del Petriccio e Belriguardo, 35 53100 Siena, (Italy).
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Pollio
authors.affiliation: Siena Biotech S.p.A, Strada del Petriccio e Belriguardo, 35 53100 Siena, (Italy). Electronic address: carla.scali@outlook.com.
authors.forename: Carla
authors.initials: C
authors.lastname: Scali
mesh_terms: D000818:Animals; D003342:Corpus Striatum / Q000378:metabolism* / Q000473:pathology / Q000821:virology*; D000229:Dependovirus / Q000235:genetics*; D004195:Disease Models, Animal; D055808:Drug Discovery / Q000379:methods*; D004660:Encephalitis / Q000378:metabolism / Q000821:virology; D005091:Exons; D005260:Female; D005822:Genetic Vectors / Q000008:administration & dosage*; D049452:Green Fluorescent Proteins / Q000378:metabolism; D000071058:Huntingtin Protein; D006816:Huntington Disease / Q000235:genetics* / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000235:genetics*; D009457:Neuroglia / Q000378:metabolism; D009474:Neurons / Q000473:pathology / Q000821:virology; D009687:Nuclear Proteins / Q000235:genetics*; D051381:Rats; D017208:Rats, Wistar; D011994:Recombinant Proteins / Q000378:metabolism
chemical_list: C499524:Htt protein, rat; D000071058:Huntingtin Protein; D009419:Nerve Tissue Proteins; D009687:Nuclear Proteins; D011994:Recombinant Proteins; D049452:Green Fluorescent Proteins
keywords: Animal model; Gene expression; Huntington's disease; In vivo spectroscopy; Neurodegeneration; Neuroinflammation immunohistochemistry; Viral vectors