A novel recombinant Newcastle disease vaccine improves post-in ovo vaccination survival with sustained protection against virulent challenge

Authors: MARCANO, VALERIE - University Of Georgia; CARDENAS-GARCIA, STIVALIS - University Of Georgia; DIEL, DIEGO - University Of Georgia; ANTONIASSI DA SILVA, LUCIANA - University Of Georgia; GOGAL JR., ROBERT - University Of Georgia; Miller, Patti; BROWN, CORRIE - University Of Georgia; BUTT, SALMAN - University Of Georgia; GORAICHUK, IRYNA - Consultant; DIMITROV, KIRIL - Consultant; Taylor, Tonya; Williams Coplin, Tina; Olivier, Timothy; STANTON, JAMES - University Of Georgia; Afonso, Claudio

Submitted to: Vaccines
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/19/2021
Publication Date: 8/26/2021
Citation: Marcano, V.C., Cardenas-Garcia, S., Diel, D.G., Antoniassi Da Silva, L.H., Gogal Jr., R.M., Miller, P.J., Brown, C.C., Butt, S.L., Goraichuk, I.V., Dimitrov, K.M., Taylor, T.L., Williams Coplin, T.D., Olivier, T.L., Stanton, J.B., Afonso, C.L. 2021. A novel recombinant Newcastle disease vaccine improves post-in ovo vaccination survival with sustained protection against virulent challenge. Vaccines. 9(9):953. https://doi.org/10.3390/vaccines9090953.
DOI: https://doi.org/10.3390/vaccines9090953

Interpretive Summary: Newcastle disease (ND) caused by Newcastle disease virus (NDV) remains endemic in poultry worldwide despite extensive vaccination programs. It is imperative to improve our control of ND. The aim of this study was to evaluate the feasibility of an in ovo mode of delivery as well as the effectiveness of a recombinant live vaccine against NDV. We hypothesized that this novel live attenuated rNDV vaccine would be effective against lethal challenge with virulent NDV and provide better protection earlier in the life, without negatively impacting survival in chickens. Our study shows that indeed, the rZJ1*L-IL4R vaccine strain can yield protection against challenge when administered in ovo at 19 days of embryonation, without negatively impacting survival post-vaccination. The data suggests that the rZJ1*L-IL4R maybe an excellent candidate for in ovo vaccination.

Technical Abstract: In ovo vaccination has been employed by the poultry industry for over 20 years to control numerous avian diseases. Unfortunately, in ovo live vaccines against Newcastle disease have significant limitations, including high embryo mortality and the inability to induce full protection during the first two weeks of life. In this study, a recombinant live attenuated Newcastle disease virus vaccine containing the antisense sequence of chicken interleukin 4 (IL-4), rZJ1*L-IL4R, was used. The rZJ1*L-IL4R vaccine was administered in ovo to naïve specific pathogen free embryonated chicken eggs (ECEs) and evaluated against a homologous challenge. Controls included a live attenuated recombinant genotype VII vaccine based on the virus ZJ1 (rZJ1*L) backbone, the LaSota vaccine and diluent alone. In the first of two experiments, ECEs were vaccinated at 18 days of embryonation (DOE) with either 104.5 or 103.5 50% embryo infectious dose (EID50/egg) and chickens were challenged at 21 days post-hatch (DPH). In the second experiment, 103.5 EID50/egg of each vaccine was administered at 19 DOE, and chickens were challenged at 14 DPH. Chickens vaccinated with 103.5 EID50/egg of rZJ1*L-IL4R had hatch rates comparable to the group that received diluent alone, whereas other groups had significantly lower hatch rates. All vaccinated chickens survived challenge without displaying clinical disease, had protective hemagglutination inhibition titers, and shed comparable levels of challenge virus. The recombinant rZJ1*L-IL4R vaccine yielded lower post-vaccination mortality rates compared with the other in ovo NDV live vaccine candidates as well as provided strong protection post-challenge.