Transfer of the CFTR gene to the lung of nonhuman primates with E1-deleted, E2a-defective recombinant adenoviruses: a preclinical toxicology study.
This paper describes a preclinical toxicology study designed to investigate the biological efficacy and safety profile of second-generation adenovirus for CFTR gene transfer into the baboon lung. This second-generation virus is deleted of E1 and contains a temperature-sensitive mutation in the E2a gene, which encodes a defective DNA-binding protein. Two distinct projects were undertaken. Group A animals received a first-generation adenovirus (i.e., deleted of E1) in an upper lobe at the time a second-generation virus was instilled into the contralateral upper lobe. The goal of study A was to compare the biology of each construct directly and to determine if an immune response to the first-generation virus affected the performance of the second-generation virus. Group B animals received a lacZ second-generation virus in an upper lobe at the same time the CFTR second-generation virus was instilled in the other upper lobe. Necropsies were performed 4 or 21 days after gene transfer and tissues were evaluated for recombinant gene expression and histopathology. Using a second-generation adenovirus, recombinant gene stability was prolonged and associated with a diminished level of perivascular inflammation as compared to first-generation vectors. Markedly diminished levels of hexon protein were present in tissues infected with second-generation as compared to first-generation virus. No evidence of viral shedding was evident. Furthermore, coadministration of first- and second-generation adenovirus did not affect the stability of transgene expression from the second-generation virus. These data suggest that second-generation adenoviral vectors provide an improved gene delivery vehicle, and thus may be useful in gene therapy for cystic fibrosis.
Goldman
M J
MJ
Institute for Human Gene Therapy, University of Pennsylvania Medical Center, Philadelphia, USA.
Litzky
L A
LA
Engelhardt
J F
JF
Wilson
J M
JM
D000256:Adenoviridae / Q000235:genetics* / Q000276:immunology; D017500:Adenovirus E1A Proteins / Q000235:genetics; D017502:Adenovirus E2 Proteins / Q000235:genetics; D000818:Animals; D001483:Base Sequence; D018893:Bronchoalveolar Lavage; D002452:Cell Count; D019005:Cystic Fibrosis Transmembrane Conductance Regulator / Q000235:genetics* / Q000378:metabolism; D004279:DNA, Viral; D003673:Defective Viruses; D017353:Gene Deletion; D005786:Gene Expression Regulation; D018014:Gene Transfer Techniques; D005822:Genetic Vectors / Q000276:immunology; D006801:Humans; D007150:Immunohistochemistry; D008168:Lung / Q000033:anatomy & histology / Q000378:metabolism*; D008297:Male; D008969:Molecular Sequence Data; D010215:Papio; D011323:Primates; D019076:Transgenes
D017500:Adenovirus E1A Proteins; D017502:Adenovirus E2 Proteins; C505032:CFTR protein, human; D004279:DNA, Viral; D019005:Cystic Fibrosis Transmembrane Conductance Regulator