title: Selection and evaluation of clinically relevant AAV variants in a xenograft liver model.
abstract: Recombinant adeno-associated viral (rAAV) vectors have shown early promise in clinical trials. The therapeutic transgene cassette can be packaged in different AAV capsid pseudotypes, each having a unique transduction profile. At present, rAAV capsid serotype selection for a specific clinical trial is based on effectiveness in animal models. However, preclinical animal studies are not always predictive of human outcome. Here, in an attempt to further our understanding of these discrepancies, we used a chimaeric human-murine liver model to compare directly the relative efficiency of rAAV transduction in human versus mouse hepatocytes in vivo. As predicted from preclinical and clinical studies, rAAV2 vectors functionally transduced mouse and human hepatocytes at equivalent but relatively low levels. However, rAAV8 vectors, which are very effective in many animal models, transduced human hepatocytes rather poorly-approximately 20 times less efficiently than mouse hepatocytes. In light of the limitations of the rAAV vectors currently used in clinical studies, we used the same murine chimaeric liver model to perform serial selection using a human-specific replication-competent viral library composed of DNA-shuffled AAV capsids. One chimaeric capsid composed of five different parental AAV capsids was found to transduce human primary hepatocytes at high efficiency in vitro and in vivo, and provided species-selected transduction in primary liver, cultured cells and a hepatocellular carcinoma xenograft model. This vector is an ideal clinical candidate and a reagent for gene modification of human xenotransplants in mouse models of human diseases. More importantly, our results suggest that humanized murine models may represent a more precise approach for both selecting and evaluating clinically relevant rAAV serotypes for gene therapeutic applications.
authors.affiliation: 1] Stanford University, School of Medicine, Departments of Pediatrics and Genetics, 269 Campus Drive, Stanford, California 94305, USA [2] Gene Transfer, Targeting and Therapeutics Core, The Salk Institute for Biological Studies, 10010 N. Torrey Pines Rd, San Diego, California 92037, USA (L.L.); Department of Haematology, University College London Cancer Institute, London WC1E 6BT, UK (A.P.D.).
authors.forename: Leszek
authors.initials: L
authors.lastname: Lisowski
authors.affiliation: 1] Gene Therapy Research Unit, The Children's Hospital at Westmead and Children's Medical Research Institute, Locked Bag 4001, Westmead, 2145 New South Wales, Australia [2] Gene Transfer, Targeting and Therapeutics Core, The Salk Institute for Biological Studies, 10010 N. Torrey Pines Rd, San Diego, California 92037, USA (L.L.); Department of Haematology, University College London Cancer Institute, London WC1E 6BT, UK (A.P.D.).
authors.forename: Allison P
authors.initials: AP
authors.lastname: Dane
authors.affiliation: Stanford University, School of Medicine, Departments of Pediatrics and Genetics, 269 Campus Drive, Stanford, California 94305, USA.
authors.forename: Kirk
authors.initials: K
authors.lastname: Chu
authors.affiliation: Stanford University, School of Medicine, Departments of Pediatrics and Genetics, 269 Campus Drive, Stanford, California 94305, USA.
authors.forename: Yue
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Gene Therapy Research Unit, The Children's Hospital at Westmead and Children's Medical Research Institute, Locked Bag 4001, Westmead, 2145 New South Wales, Australia.
authors.forename: Sharon C
authors.initials: SC
authors.lastname: Cunningham
authors.affiliation: Yecuris Corporation, Portland, Oregon 97062, USA.
authors.forename: Elizabeth M
authors.initials: EM
authors.lastname: Wilson
authors.affiliation: Oregon Stem Cell Center, Oregon Health and Science University, Portland, Oregon 97239, USA.
authors.forename: Sean
authors.initials: S
authors.lastname: Nygaard
authors.affiliation: Oregon Stem Cell Center, Oregon Health and Science University, Portland, Oregon 97239, USA.
authors.forename: Markus
authors.initials: M
authors.lastname: Grompe
authors.affiliation: 1] Gene Therapy Research Unit, The Children's Hospital at Westmead and Children's Medical Research Institute, Locked Bag 4001, Westmead, 2145 New South Wales, Australia [2] Discipline of Paediatrics and Child Health, The University of Sydney, 2145 New South Wales, Australia.
authors.forename: Ian E
authors.initials: IE
authors.lastname: Alexander
authors.affiliation: Stanford University, School of Medicine, Departments of Pediatrics and Genetics, 269 Campus Drive, Stanford, California 94305, USA.
authors.forename: Mark A
authors.initials: MA
authors.lastname: Kay
mesh_terms: D000818:Animals; D002213:Capsid / Q000378:metabolism; D036022:Capsid Proteins / Q000235:genetics / Q000378:metabolism; D006528:Carcinoma, Hepatocellular / Q000235:genetics / Q000473:pathology; D045744:Cell Line, Tumor; D002478:Cells, Cultured; D002678:Chimera / Q000235:genetics / Q000378:metabolism; D002986:Clinical Trials as Topic; D000229:Dependovirus / Q000235:genetics* / Q000302:isolation & purification; D004195:Disease Models, Animal; D005260:Female; D015316:Genetic Therapy / Q000379:methods*; D005822:Genetic Vectors / Q000235:genetics*; D022781:Hepatocytes / Q000166:cytology / Q000378:metabolism / Q000473:pathology / Q000637:transplantation; D064593:Heterografts / Q000378:metabolism*; D006801:Humans; D008099:Liver / Q000166:cytology / Q000378:metabolism* / Q000473:pathology; D008297:Male; D051379:Mice; D013045:Species Specificity; D014161:Transduction, Genetic / Q000379:methods*; D019076:Transgenes / Q000235:genetics*
chemical_list: D036022:Capsid Proteins