An influenza A virus hemagglutinin (HA) epitope inserted in and expressed from several loci of the infectious bursal disease virus genome induces HA-specific antibodies
The N-terminus of infectious bursal disease virus (IBDV) VP5 has been shown to be capable of tolerating the insertion of small epitopes. The objective of the present study was to determine if IBDV genomic sites, including the 5’ end of vp5, could carry an influenza A virus hemagglutinin (HA) epitope. HA-expressing IBDVs were generated when the HA epitope was fused to the N-terminus of VP5 (HA5-IBDV) or VP4 (HA4-IBDV) or the C-terminus of VP1 (1HA-IBDV). Viral titers obtained after co-transfection with cDNA from the ha-containing segment and the complementary genomic segment were 1.3 × 104, 3.7 × 103 and 3.8 × 104 pfu/ml for HA5-IBDV, HA4-IBDV and 1HA-IBDV, respectively. The HA tag expression remained stable after 10 passages when the tag gene was inserted into the vp4 and vp1 genes. HA-IBDVs did not cause pathogenicity in specific-pathogen-free (SPF) chickens. However, only HA4-IBDV and 1HA-IBDV induced HA-specific antibodies, which were measured by ELISA with a maximum optical density (OD) value of 0.701 and 0.769, respectively, at 24 days after infection. Thus, IBDV can potentially be employed as a bivalent viral vector when the epitope is fused with VP4 or VP1.
KeywordsAntibody Titer Infectious Bursal Disease Virus Infectious Pancreatic Necrosis Virus Infectious Bursal Disease Virus Strain Infectious Bursal Disease Virus Infection
We thank Debby Sherman for her assistance with electron microscopy. We also thank Bong-Suk Kim, Yi-Ning Chen, Chih-Chun Lee, Chun-Yu Tung, Wan-Jung Chen and Ching Giap Tan for their help with the animal study.
- 6.Castón JR, Martínez-Torrecuadrada JL, Maraver A, Lombardo E, Rodríguez JF, Casal JI, Carrascosa JL (2001) C terminus of infectious bursal disease virus major capsid protein VP2 is involved in definition of the T number for capsid assembly. J Virol 75:10815–10828PubMedCentralPubMedCrossRefGoogle Scholar
- 20.Luque D, Saugar I, Rodríguez JF, Verdaguer N, Garriga D, Martín CS, Velázquez-Muriel JA, Trus BL, Carrascosa JL, Castón JR (2007) Infectious bursal disease virus capsid assembly and maturation by structural rearrangements of a transient molecular switch. J Virol 81:6869–6878PubMedCentralPubMedCrossRefGoogle Scholar
- 22.Martin Caballero J, Garzón A, González-Cintado L, Kowalczyk W, Jimenez Torres I, Calderita G, Rodriguez M, Gondar V, Bernal JJ, Ardavín C, Andreu D, Zürcher T, von Kobbe C (2012) Chimeric infectious bursal disease virus-like particles as potent vaccines for eradication of established HPV-16 E7-dependent tumors. PLoS One 7:e52976PubMedCentralPubMedCrossRefGoogle Scholar