title: [Inhibition of infectious bursal disease virus replication in chicken embryos by miRNAs delivered by recombinant avian adeno-associated viral vector].
abstract: OBJECTIVE
  We studied the inhibition of infectious bursal disease virus (IBDV) replication in chicken embryos by recombinant avian adeno-associated virus (AAAV)-delivered VP1- and VP2-specific microRNAs (miRNAs).
  
  
  RESULTS
  We co-transfected AAV-293 cells with the VP1- or VP2 gene-specific miRNA expression vector pAITR-RFPmiVP1 or AITR-RFPmiVP2E, AAAV packaging vector pcDNA-ARC and adenovirus helper vector pHelper, resulting in recombinant virus rAAAV-RFPmiVP1 or rAAAV-RFPmiVP2E. We also generated the recombinant viruses rAAAV-RFP (without miRNA expression cassette) and rAAAV-RFPmiVP2con (expressing control miRNA) using the same method as the control purpose. Electron microscopy showed that the recombinant viruses had a typical morphology of AAV. We confirmed the presence of miRNA expression cassette in the recombinant viral genomes by using PCR. Our poly (A)-tailed RT-PCR showed correct expression of the miRNAs in the rAAAV-transduced DF-1 cells. We inoculated the recombinant viruses individually into 8-day-old SPF chicken embryos and then challenged them using Lukert strain IBDV on day 2 after inoculation. Our IBDV titration assay showed that the 50% tissue culture infectious dose (TCID50) of rAAAV-RFP- or rAAAV-RFPmiVP2con-inoculated group was 8.0 log10, whereas the TCID50 of rAAAV-RFPmiVP1-inoculated group decreased to 1.0 and 0.8 log10 on day 3 and 6 after challenge, respectively. Similarly, the TCID50 of rAAAV-RFPmiVP2E-inoculated group decreased to 1.5 and 2.0 log10, respectively.
  
  
  CONCLUSIONS
  These data suggest that rAAAV can transduce efficiently chicken embryos and the expressed VP1- and VP2-specific miRNAs can inhibit the replication of IBDV efficiently.
authors.affiliation: College of Veterinary Medicine, Yangzhou University, Yangzhou 225009, China.
authors.forename: Pengpeng
authors.initials: P
authors.lastname: Shen
authors.forename: Yongjuan
authors.initials: Y
authors.lastname: Wang
authors.forename: Huaichang
authors.initials: H
authors.lastname: Sun
authors.forename: Xinyu
authors.initials: X
authors.lastname: Zhang
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Xia
mesh_terms: D000818:Animals; D018175:Birnaviridae Infections / Q000235:genetics / Q000662:veterinary* / Q000821:virology; D002642:Chick Embryo; D002645:Chickens; D000229:Dependovirus / Q000235:genetics / Q000378:metabolism; D015536:Down-Regulation; D005822:Genetic Vectors / Q000235:genetics / Q000378:metabolism; D007243:Infectious bursal disease virus / Q000235:genetics / Q000502:physiology*; D035683:MicroRNAs / Q000235:genetics* / Q000378:metabolism; D011201:Poultry Diseases / Q000235:genetics / Q000821:virology*; D014759:Viral Envelope Proteins / Q000235:genetics / Q000378:metabolism; D014779:Virus Replication
chemical_list: D035683:MicroRNAs; D014759:Viral Envelope Proteins