Subpopulations in aMPV vaccines are unlikely to be the only cause of reversion to virulence.

Published on May 1, 2015in Vaccine3.27
· DOI :10.1016/j.vaccine.2015.03.092
Giovanni Franzo10
Estimated H-index: 10
(UNIPD: University of Padua),
C. J. Naylor17
Estimated H-index: 17
(University of Liverpool)
+ 5 AuthorsMattia Cecchinato12
Estimated H-index: 12
(UNIPD: University of Padua)
Abstract Avian metapneumovirus (aMPV) infects respiratory and reproductive tracts of domestic poultry, often involving secondary infections, and leads to serious economic losses in most parts of the world. While in general disease is effectively controlled by live vaccines, reversion to virulence of those vaccines has been demonstrated on several occasions. Consensus sequence mutations involved in the process have been identified in more than one instance. In one previous subtype A aMPV candidate vaccine study, small subpopulations were implicated. In the current study, the presence of subpopulations in a subtype B vaccine was investigated by deep sequencing. Of the 19 positions where vaccine (strain VCO3/50) and progenitor (strain VCO3/60616) consensus sequences differed, subpopulations were found to have sequence matching progenitor sequence in 4 positions. However none of these mutations occurred in a virulent revertant of that vaccine, thereby demonstrating that the majority progenitor virus population had not survived the attenuation process, hence was not obviously involved in any return to virulence. However within the vaccine, a single nucleotide variation was found which agreed with consensus sequence of a derived virulent revertant virus, hence this and other undetected, potentially virulent subpopulations, can be involved in reversion. Much deeper sequencing of progenitor, vaccine and revertant may clarify whether problematic virulent subpopulations are present and therefore whether these need to be routinely removed during aMPV vaccine preparation prior to registration and release.
  • References (11)
  • Citations (3)
#1Mattia Cecchinato (UNIPD: University of Padua)H-Index: 12
#2E. Catelli (UNIBO: University of Bologna)H-Index: 12
Last.C. J. Naylor (University of Liverpool)H-Index: 17
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#1Anthony Bolger (MPG: Max Planck Society)H-Index: 10
#2Marc Lohse (MPG: Max Planck Society)H-Index: 20
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#1Mattia Cecchinato (UNIPD: University of Padua)H-Index: 12
#2Caterina Lupini (UNIBO: University of Bologna)H-Index: 8
Last.E. Catelli (UNIBO: University of Bologna)H-Index: 12
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#1Ben Langmead (Johns Hopkins University)H-Index: 20
#2Steven L. Salzberg (Johns Hopkins University)H-Index: 121
#1Osvaldo Zagordi (Swiss Institute of Bioinformatics)H-Index: 13
#2Arnab Bhattacharya (ETH Zurich)H-Index: 1
Last.Niko Beerenwinkel (Swiss Institute of Bioinformatics)H-Index: 39
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#1Miki Sugiyama (Merial)H-Index: 2
#2Hiroshi Ito (Tottori University)H-Index: 25
Last.Toshihiro Ito (Tottori University)H-Index: 25
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#1C. J. Naylor (University of Liverpool)H-Index: 17
#2Roger Ling (Warw.: University of Warwick)H-Index: 9
Last.Andrew J. Easton (Warw.: University of Warwick)H-Index: 37
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#1E. Catelli (UNIBO: University of Bologna)H-Index: 12
#2Cecchinato Mattia (UNIBO: University of Bologna)H-Index: 6
Last.C. J. Naylor (University of Liverpool)H-Index: 17
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