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. 2019 Mar 28;14(3):e0213866.
doi: 10.1371/journal.pone.0213866. eCollection 2019.

Attenuated infectious laryngotracheitis virus vaccines differ in their capacity to establish latency in the trigeminal ganglia of specific pathogen free chickens following eye drop inoculation

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Attenuated infectious laryngotracheitis virus vaccines differ in their capacity to establish latency in the trigeminal ganglia of specific pathogen free chickens following eye drop inoculation

Dulari S Thilakarathne et al. PLoS One. .

Abstract

Infectious laryngotracheitis (ILT) is a respiratory disease that affects chickens. It is caused by the alphaherpesvirus, infectious laryngotracheitis virus (ILTV). This virus undergoes lytic replication in the epithelial cells of the trachea and upper respiratory tract (URT) and establishes latent infection in the trigeminal ganglia (TG) and trachea. Live attenuated vaccines are widely used to control ILT. At least one of these vaccines can establish latent infections in chickens, but this has not been demonstrated for all vaccines. The aim of the current study was to determine the capacity of three commercially available vaccines (SA2, A20 and Serva) and a glycoprotein G deletion mutant vaccine candidate (ΔgG ILTV) to establish latent infection in the TG of specific pathogen free (SPF) chickens. Five groups of 7-day-old SPF chickens were eye-drop vaccinated with either one of the vaccine strains or mock-vaccinated with sterile media and followed until 20 or 21 days post-vaccination (dpv). ILTV DNA was detected at 20-21 dpv in the TG of 23/40 (57.5%) vaccinated SPF chickens (SA2 = 10/10; A20 = 6/10; Serva = 3/10; ΔgG = 4/10) by PCR, but virus could not be reactivated from TG co-cultivated with primary chicken embryo kidney cells. In the birds from which ILTV DNA was detected in the TG, ILTV DNA could not be detected in the URT or trachea of 3 birds in each of the SA2, A20 and Serva vaccinated groups, and in 4 birds in the ΔgG vaccinated group, indicating that these birds were latently infected in the absence of active lytic replication and virus shedding. Results from this study demonstrate the capacity of commercial ILTV vaccines to establish latent infections and underline their importance in the epidemiology of this disease.

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Conflict of interest statement

The authors have declared that no competing interests exist.

Figures

Fig 1
Fig 1. Summary of ILTV DNA detection results at day 21 post vaccination.
The presence of ILTV DNA in the TG only suggests latent infection. The presence of ILTV DNA in the TG and URT suggests concurrent latent and lytic infection. The presence of ILTV DNA in the URT only suggests lytic infection.

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References

    1. Kirkpatrick NC, Mahmoudian A, Colson CA, Devlin JM, Noormohammadi AH. Relationship between mortality, clinical signs and tracheal pathology in infectious laryngotracheitis. Avian Pathology. 2006;35(6):449–53. 10.1080/03079450601028803 - DOI - PubMed
    1. Lee S-W, Hartley CA, Coppo MJ, Vaz PK, Legione AR, Quinteros JA, et al. Growth Kinetics and Transmission Potential of Existing and Emerging Field Strains of Infectious Laryngotracheitis Virus. PloS one. 2015;10(3):e0120282 10.1371/journal.pone.0120282 - DOI - PMC - PubMed
    1. Vagnozzi A, Riblet SM, Williams SM, Zavala G, García M. Infection of broilers with two virulent strains of infectious laryngotracheitis virus: criteria for evaluation of experimental infections. Avian diseases. 2015;59(3):394–9. 10.1637/11075-033115-Reg.1 - DOI - PubMed
    1. Raggi L, Brownell J, Stewart G. Effects of infectious laryngotracheitis virus on egg production and quality. Poultry Science. 1961;40(1):134–40.
    1. García M, Volkening J, Riblet S, Spatz S. Genomic sequence analysis of the United States infectious laryngotracheitis vaccine strains chicken embryo origin (CEO) and tissue culture origin (TCO). Virology. 2013;440(1):64–74. 10.1016/j.virol.2013.02.007 - DOI - PubMed

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