Live Attenuated Vaccine Based on Duck Enteritis Virus against Duck Hepatitis A Virus Types 1 and 3

• Published in: Frontiers in microbiology Vol. 7; p. 1613
• Main Authors: Zou, Zhong, Ma, Ji, Huang, Kun, Chen, Huanchun, Liu, Ziduo, Jin, Meilin
• Format: Journal Article
• Language: English
• Published: Switzerland Frontiers Media S.A 10-10-2016
• Subjects: 2A-element; Duck enteritis virus; Duck hepatitis A virus type 1; duck hepatitis A virus type 3; Microbiology; Vaccines; VP1; duck enteritis virus; vaccine; duck hepatitis A virus type 1; VP1; 2A-element; duck hepatitis A virus type 3
• ISSN: 1664-302X; 1664-302X
• DOI: 10.3389/fmicb.2016.01613

As causative agents of duck viral hepatitis, duck hepatitis A virus type 1 (DHAV-1) and type 3 (DHAV-3) causes significant economic losses in the duck industry. However, a licensed commercial vaccine that simultaneously controls both pathogens is currently unavailable. Here, we generated duck enteritis virus recombinants (rC-KCE-2VP1) containing both VP1 from DHAV-1 (VP1/DHAV-1) and VP1 from DHAV-3 (VP1/DHAV-3) between UL27 and UL26. A self-cleaving 2A-element of FMDV was inserted between the two different types of VP1, allowing production of both proteins from a single open reading frame. Immunofluorescence and Western blot analysis results demonstrated that both VP1 proteins were robustly expressed in rC-KCE-2VP1-infected chicken embryo fibroblasts. Ducks that received a single dose of rC-KCE-2VP1 showed potent humoral and cellular immune responses and were completely protected against challenges of both pathogenic DHAV-1 and DHAV-3 strains. The protection was rapid, achieved as early as 3 days after vaccination. Moreover, viral replication was fully blocked in vaccinated ducks as early as 1 week post-vaccination. These results demonstrated, for the first time, that recombinant rC-KCE-2VP1 is potential fast-acting vaccine against DHAV-1 and DHAV-3.