Recombinant canarypox virus expressing the VP2 protein of infectious bursal disease virus induces protection in vaccinated SPF chickens

FLAVIA ZANETTI; CARDONA ROMINA; FERDERICO CARLOS; CHIMENO ZOTH SILVINA; CALAMANTE, GABRIELA

Virologica Sinica

Springer

Año: 2016

Infectious bursal disease virus(IBDV) causes infectious bursal disease, a highly contagious immunosuppressive diseasethat affects young chickens and causes economic losses in the poultry industryworldwide. IBDV replicates mainly in actively dividing B lymphocytes within thebursa of Fabricius (BF), leading to immunosuppression in affected flocks. Viral protein 2 (VP2), the only structuralcomponent of the IBDV icosahedral capsid, is the major antigen responsible for inducingprotective immunity in the host. Canarypox virus (CNPV),which belongs to the Avipoxvirus genus, has been widely used todevelop recombinant viral vectors for in vivo expression of antigens derived frommammalian pathogens. CNPV-based vectors induce excellent protective immune responses with afavorable safety profile because they do not replicate in vaccinatedanimals. Consequently, several recombinant CNPVs are now commercial veterinaryvaccines. Despite the success of viral vectors formammals, few studies have assessed the effectiveness of recombinant CNPV as avaccine candidate for birds. Wepreviously constructed and characterized a recombinant CNPV expressing IBDV VP2(CN048-VP2) and demonstrated its immunogenicity by intramuscular administration inspecific pathogen free (SPF) chickens. Herein, we evaluated the replication statusof CN048-VP2 and the protection induced against IBDV infection with single-dosesubcutaneous administration in 1-day-old SPF chickens. The results demonstratedthat CN048-VP2 could induce protection against IBDV infection in vaccinated SPFchickens.