Cloning of the genome of Alcelaphine herpesvirus 1 as an infectious and pathogenic bacterial artificial chromosome.
Alcelaphine herpesvirus 1 (AlHV-1), carried asymptomatically by wildebeest, causes malignant catarrhal fever (MCF) following cross-species transmission to a variety of susceptible species of the order Artiodactyla. The study of MCF pathogenesis has been impeded by an inability to produce recombinant virus, mainly due to the fact that AlHV-1 becomes attenuated during passage in culture. In this study, these difficulties were overcome by cloning the entire AlHV-1 genome as a stable, infectious and pathogenic bacterial artificial chromosome (BAC). A modified loxP-flanked BAC cassette was inserted in one of the two large non-coding regions of the AlHV-1 genome. This insertion allowed the production of an AlHV-1 BAC clone stably maintained in bacteria and able to regenerate virions when transfected into permissive cells. The loxP-flanked BAC cassette was excised from the genome of reconstituted virions by growing them in permissive cells stably expressing Cre recombinase. Importantly, BAC-derived AlHV-1 virions replicated comparably to the virulent (low-passage) AlHV-1 parental strain and induced MCF in rabbits that was indistinguishable from that of the virulent parental strain. The availability of the AlHV-1 BAC is an important advance for the study of MCF that will allow the identification of viral genes involved in MCF pathogenesis, as well as the production of attenuated recombinant candidate vaccines.
Department of Infectious and Parasitic Diseases, Immunology-Vaccinology (B43b), Faculty of Veterinary Medicine, University of Liège, B-4000 Liège, Belgium.
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B
Dewals
Department of Infectious and Parasitic Diseases, Immunology-Vaccinology (B43b), Faculty of Veterinary Medicine, University of Liège, B-4000 Liège, Belgium.
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Boudry
Department of Infectious and Parasitic Diseases, Immunology-Vaccinology (B43b), Faculty of Veterinary Medicine, University of Liège, B-4000 Liège, Belgium.
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Gillet
Department of Infectious and Parasitic Diseases, Immunology-Vaccinology (B43b), Faculty of Veterinary Medicine, University of Liège, B-4000 Liège, Belgium.
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N
Markine-Goriaynoff
Department of Pathology, Faculty of Medicine, University of Liège, B-4000 Liège, Belgium.
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de Leval
The Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, Midlothian EH26 0PZ, UK.
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Haig
Department of Infectious and Parasitic Diseases, Immunology-Vaccinology (B43b), Faculty of Veterinary Medicine, University of Liège, B-4000 Liège, Belgium.
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Vanderplasschen
D000818:Animals; D002417:Cattle; D002460:Cell Line; D022202:Chromosomes, Artificial, Bacterial / Q000235:genetics*; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000235:genetics; D018142:Gammaherpesvirinae / Q000235:genetics*; D005822:Genetic Vectors; D016679:Genome, Viral; D008304:Malignant Catarrh / Q000821:virology*; D011817:Rabbits; D014169:Transformation, Bacterial; D014771:Virion / Q000472:pathogenicity / Q000502:physiology; D014774:Virulence; D014779:Virus Replication