Mutations in VP0 and 2C Proteins of Duck Hepatitis A Virus Type 3 Attenuate Viral Infection and Virulence

Duck hepatitis A virus (DHAV) is prevalent worldwide and has caused significant economic losses. As the predominant serotype in China, DHAV-3 has become a major challenge to the local duck industry. Here the genetics and pathogenesis of a virulent DHAV-3 strain and its embryo-passaged strain were assessed. There were only two amino acid substitutions (Y164N in VP0 protein and L71I in 2C protein) introduced during the adaptation process. The pathogenicity of these strains was further evaluated in vivo. Clinical signs, gross pathology, and histopathological analysis showed that the embryo-passaged strain was attenuated. Meanwhile, the viral RNA loads were significantly lower in the liver tissues of the ducklings infected with the attenuated strain. As expected, infection with the virulent and attenuated strains led to the activation of different innate immune genes. We suspected that the loss of replication efficiency in ducklings was responsible for the attenuation phenotype of the embryo-passaged strain. In addition, different innate immune responses in the liver of ducklings were at least partly responsible for the differential infectivity phenotype. These findings provide new insights into the genetics and pathogenesis of DHAV-3, which may aid the development of new vaccines and the implementation of immunization strategies.

Download Full-text

One-tube RT-PCR for the Simultaneous Detection and Typing Duck Hepatitis A Virus Subtypes 1 and 3

10.20944/preprints201901.0212.v1 ◽

2019 ◽

Author(s):

Xueming Chen ◽

Yuhuan Chen ◽

Chunguo Liu ◽

Xiaojun Li ◽

Hongyu Liu ◽

...

Keyword(s):

Hepatitis A ◽

Hepatitis A Virus ◽

Simultaneous Detection ◽

Clinical Signs ◽

Economic Losses ◽

Clinical Samples ◽

Rt Pcr ◽

Genotype 3 ◽

Duck Hepatitis ◽

Novel Approach

The co-circulation of duck hepatitis A virus subtypes 1 (DHAV-1) and 3 (DHAV-3) in ducklings has resulted in significant economic losses. Because ducklings infected with DHAV-1 or DHAV-3 show similar clinical signs and gross lesions, it is important to discriminate these subtypes as early as possible for better clinical management. On the basis of multiple alignments of the 5′-noncoding region sequences of strains DHAV-1 and DHAV-3, universal and type-specific primers were designed and synthesized. Using the primers in a one-tube reverse transcription-PCR (RT-PCR) assay, reference strains of DHAV-1 and DHAV-3 (isolated over a span of 60 years and covering many different countries) were successfully amplified, indicating that the primer sequences were completely conserved. The amplicon sequences results and the sizes of amplicons from reference DHAV-1 and DHAV-3 isolates correlated completely with their genotypes. Moreover, with this one-tube RT-PCR system, the amplicon sizes of liver samples of reference DHAV-1- or DHAV-3-infected birds matched perfectly with their respective genotypes, as determined by virus isolation and neutralization tests. No other RNA viruses of duck origin were detected with the synthesized primers. The sensitivity of viral RNA detection was 10 pg. With this system, 20% genotype 1, 45% genotype 3, and 9% co-infection of the two genotypes were detected in 55 clinical samples. This novel approach could be used for the rapid genotyping DHAV-1 and/or DHAV-3 infection in routine clinical surveillance or epidemiologic screening.

Download Full-text

Assessment of the Effect of Baicalin on Duck Virus Hepatitis

Current Molecular Medicine ◽

10.2174/1566524019666190405095301 ◽

2019 ◽

Vol 19 (5) ◽

pp. 376-386 ◽

Cited By ~ 1

Author(s):

Yun Chen ◽

Fangke Yao ◽

Ke Ming ◽

Jintong Shi ◽

Ling Zeng ◽

...

Keyword(s):

Hepatitis A Virus ◽

Antiviral Drug ◽

Economic Losses ◽

Virus Hepatitis ◽

Mechanism Study ◽

Curative Effect ◽

Chinese Medicinal Herb ◽

Duck Hepatitis

Background: Duck virus hepatitis (DVH) caused by duck hepatitis A virus type 1 (DHAV-1) is a malignant disease in ducklings, causing economic losses in the duck industry. However, there is still no antiviral drug against DHAV-1 in the clinic. Objective: Our aim is to investigate the anti-DHAV-1 effect of baicalin, which is a flavonoid derived from the Chinese medicinal herb huangqin (Scutellaria baicalensis Georgi). Methods: Here, we first detected its anti-DHAV-1 ability in vitro and in vivo. At the same time, the inhibition of baicalin on DHAV-1 reproduction was determined. Finally, we tested and verified the anti-oxidative and immuno-enhancing roles of baicalin on its curative effect on DVH. Results: Baicalin possessed anti-DHAV-1 effect. It improved the cytoactive of DEH which was infected by DHAV-1 as well as reduced the DHAV-1 reproduction in DEH. Under baicalin treatment, mortality of ducklings infected by DHAV-1 decreased, additionally the DHAV-1 level and liver injury in such ducklings were significantly reduced or alleviated. The in vitro mechanism study indicated baicalin inhibited DHAV-1 reproduction via interfering the viral replication and release. Furthermore, the in vivo mechanism study manifested both the anti-oxidative and immuno-enhancing abilities of baicalin, which played crucial roles in its curative effect on DVH. Conclusion: This study may provide a scientific basis for developing baicalin as one or a part of the anti-DHAV-1 drugs.

Download Full-text

Virulent and attenuated strains of duck hepatitis A virus elicit discordant innate immune responses in vivo

Journal of General Virology ◽

10.1099/vir.0.070011-0 ◽

2014 ◽

Vol 95 (12) ◽

pp. 2716-2726 ◽

Cited By ~ 10

Author(s):

Cuiping Song ◽

Ying Liao ◽

Wei Gao ◽

Shengqing Yu ◽

Yingjie Sun ◽

...

Keyword(s):

Nitric Oxide ◽

Immune Responses ◽

Hepatitis A ◽

Hepatitis A Virus ◽

Transmembrane Protein ◽

Oligoadenylate Synthetase ◽

Strong Immune Response ◽

Duck Hepatitis ◽

Serum Aspartate Aminotransferase

Previous studies of duck hepatitis A virus infection have focused only on the pathogenicity and host response of one strain. Here, we show that the virulent SH strain and the attenuated FC64 strain induced varied pathogenicity, apoptosis and immune responses in the livers of 1-day-old ducklings. SH infection caused apoptosis and visible lesions in the liver; serum aspartate aminotransferase, alanine transaminase, alkaline phosphatase, γ-glutamyltransferase and total bilirubin activities were markedly upregulated; and ducklings died at 36 h post-infection (p.i.). However, FC64 infection did not induce significant symptoms or impair liver function, and all of the infected ducklings remained healthy. In addition, both virus strains replicated well in the liver, spleen and intestine, whilst the SH strain replicated more efficiently than FC64. IFN-γ, IL-2, inducible nitric oxide synthase and nitric oxide were strongly induced by SH infection, and may be associated with the pathogenicity of the SH strain. IFN-α, IFN-β, IFN-stimulated transmembrane protein 1, IFN-stimulated gene 12, 2′,5′-oligoadenylate synthetase-like and IL-6 were moderately induced by SH infection at 24 h p.i., and dramatically induced by FC64 infection at 36 h p.i. The intensive induction of cytokines by FC64 may be involved in restriction of virus replication and stimulation of adaptive immune responses. Ducklings inoculated with FC64 produced high levels of antiviral antibodies within 45 days p.i. The low virulence and strong immune response of FC64 rendered this strain a good vaccine candidate, as confirmed by a protective assay in this study.

Download Full-text

Comparison of the anti-duck hepatitis A virus activities of phosphorylated and sulfated Astragalus polysaccharides

Experimental Biology and Medicine ◽

10.1177/1535370216672750 ◽

2016 ◽

Vol 242 (3) ◽

pp. 344-353 ◽

Cited By ~ 8

Author(s):

Yixuan Wang ◽

Yun Chen ◽

Hongxu Du ◽

Jingjing Yang ◽

Ke Ming ◽

...

Keyword(s):

Hepatitis A ◽

Hepatitis A Virus ◽

Sodium Tripolyphosphate ◽

Chlorosulfonic Acid ◽

Polymerase Chain Reaction Method ◽

Viral Multiplication ◽

Duck Hepatitis ◽

Antiviral Activities

Duck hepatitis A virus (DHAV) (Picornaviridae) causes an infectious disease in ducks which results in severe losses in duck industry. However, the proper antiviral supportive drugs for this disease have not been discovered. Polysaccharide is the main ingredient of Astragalus that has been demonstrated to directly and indirectly inhibit RNA of viruses replication. In this study, the antiviral activities of Astragalus polysaccharide (APS) and its derivatives against DHAV were evaluated and compared. APS was modified via the sodium trimetaphosphate and sodium tripolyphosphate (STMP-STPP) method and chlorosulfonic acid-pyridine method to obtain its phosphate (pAPS) and sulfate (sAPS), respectively. The infrared structures of APS, pAPS, and sAPS were analyzed with the potassium bromide disc method. Additionally, the antiviral activities were evaluated with the MTT ((4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide) method in vitro and the artificial inoculation method in vivo. The clinical therapy effects were evaluated by mortality rate, liver function-related biochemical indicators, and visual changes in pathological anatomy. The anti-DHAV proliferation effects of APS, pAPS, and sAPS on the viral multiplication process in cell and blood were observed with the reverse transcription-polymerase chain reaction method. The results revealed that pAPS inhibited DHAV proliferation more efficiently in the entire process of viral multiplication than APS and sAPS. Moreover, only pAPS significantly improved the survival rate to 33.5% and reduced the DHAV particle titer in the blood as well as liver lesions in clinical trials. The results indicated that pAPS exhibited greater anti-DHAV activity than APS and sAPS both in vitro and in vivo.

Download Full-text

Recombinant Duck Enteritis Virus-Vectored Bivalent Vaccine Effectively Protects Against Duck Hepatitis A Virus Infection in Ducks

Frontiers in Microbiology ◽

10.3389/fmicb.2021.813010 ◽

2021 ◽

Vol 12 ◽

Author(s):

Fuchun Yang ◽

Peng Liu ◽

Xiaohan Li ◽

Rui Liu ◽

Li Gao ◽

...

Keyword(s):

Neutralizing Antibodies ◽

Hepatitis A ◽

Hepatitis A Virus ◽

Duck Enteritis Virus ◽

Economic Losses ◽

Reading Frame ◽

Recombinant Viruses ◽

Duck Hepatitis ◽

Enteritis Virus ◽

Type 3

Duck enteritis virus (DEV) and duck hepatitis A virus (DHAV) are prevalent duck pathogens, causing significant economic losses in the duck industry annually. Using a fosmid-based rescue system, we generated two DEV recombinants, rDEV-UL26/27-P13C and rDEV-US7/8-P13C, in which the P1 and 3C genes from DHAV type 3 (DHAV-3) were inserted into the DEV genome between genes UL26 and UL27 or genes US7 and US8. We inserted a self-cleaving 2A-element between P1 and 3C, allowing the production of both proteins from a single open reading frame. P1 and 3C were simultaneously expressed in infected chicken embryo fibroblasts, with no difference in growth kinetics between cells infected with the recombinant viruses and those infected with the parent DEV. Both recombinant viruses induced neutralizing antibodies against DHAV-3 and DEV in ducks. A single dose of the recombinant viruses induced solid protection against lethal DEV challenge and completely prevented DHAV-3 infection as early as 7 days post-vaccination. These recombinant P1- and 3C-expressing DEVs provide potential bivalent vaccines against DEV and DHAV-3 infection in ducks.

Download Full-text

Circulation and in vivo distribution of duck hepatitis A virus types 1 and 3 in infected ducklings

Archives of Virology ◽

10.1007/s00705-015-2648-z ◽

2015 ◽

Vol 161 (2) ◽

pp. 405-416 ◽

Cited By ~ 19

Author(s):

Shao-Li Lin ◽

Ri-Chao Cong ◽

Rui-Hua Zhang ◽

Jun-Hao Chen ◽

Lin-Lin Xia ◽

...

Keyword(s):

Hepatitis A ◽

Hepatitis A Virus ◽

In Vivo Distribution ◽

Duck Hepatitis

Download Full-text

Pathogenicity of duck hepatitis A virus type 3 and innate immune responses of the ducklings to virulent DHAV-3

Molecular Immunology ◽

10.1016/j.molimm.2018.01.007 ◽

2018 ◽

Vol 95 ◽

pp. 30-38 ◽

Cited By ~ 5

Author(s):

Xuelian Zhang ◽

Chong Cao ◽

Zhehui Qu ◽

Wenjing Zhang ◽

Yue Liu ◽

...

Keyword(s):

Immune Responses ◽

Virus Type ◽

Hepatitis A ◽

Hepatitis A Virus ◽

Innate Immune ◽

Innate Immune Responses ◽

Duck Hepatitis ◽

Type 3

Download Full-text

Virus isolate from carp: genetic characterization reveals a novel picornavirus with two aphthovirus 2A-like sequences

Journal of General Virology ◽

10.1099/vir.0.058172-0 ◽

2014 ◽

Vol 95 (1) ◽

pp. 80-90 ◽

Cited By ~ 23

Author(s):

Jeannette Lange ◽

Marco Groth ◽

Dieter Fichtner ◽

Harald Granzow ◽

Barbara Keller ◽

...

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Sequence Analysis ◽

Phylogenetic Trees ◽

Hepatitis A ◽

Hepatitis A Virus ◽

Clinical Symptoms ◽

Clinical Signs ◽

Duck Hepatitis ◽

A Genome

Picornaviruses have been isolated from a variety of hosts, mainly mammals and birds. Here, we describe the sequence analysis of carp picornavirus 1 (CPV-1) F37/06 that was isolated from an organ pool (heart, brain, liver) of a common carp (Cyprinus carpio). This carp perished after an accidental discharge of liquid manure into a fish pond and presented without obvious clinical symptoms. Experimental intraperitoneal infection of young carp with CPV-1 revealed no clinical signs, but the virus was re-isolated from various organs. Sequence analysis of almost the complete genome (7632 nt excluding the poly-A tract) revealed a novel picornavirus clade. In phylogenetic trees, the polymerase sequence clusters with parechoviruses, duck hepatitis A virus, eel picornavirus and aquamavirus A. The ORF includes 6807 nt and encodes a polyprotein of 2269 amino acids. CPV-1 has a genome layout like that of picornaviruses except for the presence of two aphthovirus 2A-like NPGP sequence motifs: VPg+5′UTR[1AB-1C-1D-2A1npgp/2A2npgp-2B-2CATPase/3A-3BVPg-3Cpro-3Dpol]3′UTR-poly-A. 2A1npgp and 2A2npgp are separated by 133 amino acids. The proteins 2A2npgp, 2B, 3A and 3BVPg have no significant similarity to the corresponding proteins of other picornaviruses. Amino acid identities of the orthologous proteins P1, 2C, 3Cpro and 3Dpol range from 16.4 to 40.8 % in the eel picornavirus/CPV-1 comparison. 3Dpol shows the closest similarity to eel picornavirus, with an amino acid identity of 40.8 %, followed by human parechovirus (36.5 %), duck hepatitis A virus (32.7 %) and swine pasivirus (29.3 %). Both the unique genome organization and low sequence similarity support the assignment of CPV-1 to a novel picornavirus species within a novel genus.

Download Full-text