DETECTION AND DIFFERENTIATION OF THE VACCINE STRAIN AND FIELD ISOLATES OF DUCK HEPATITIS A VIRUS TYPE 1 USING REAL-TIME RT-PCR AND HIGH RESOLUTION MELTING ASSAYS

Duck hepatitis A virus type 1 (DHAV-1) infection is a highly contagious and fatal disease of young ducklings. A live attenuated vaccine strain designated as 5886 has been used in Taiwan for the control of DHAV-1. Although several molecular biological methods are reported for diagnosis of DHAV-1 infection, none of them is able to discriminate between the vaccine strain and field viruses of DHAV-1. In the present study, a real-time reverse transcriptase polymerase chain reaction (RT-PCR) and high resolution melting (HRM) assay was developed for rapid detection and differentiation between the vaccine strain and field viruses of DHAV-1. This assay is highly specific for DHAV-1 and the detection limit is about 100 copies of the viral RNA. Experiments using fecal samples collected from ducklings experimentally infected with DHAV-1 showed that DHAV-1 could be detected in fecal samples as early as 6 h post-infection. In summary, a real-time RT-PCR and HRM assay is developed in this study and this assay could be valuable for diagnosis and surveillance of DHAV-1 infection in the field.

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Improved duplex RT-PCR assay for differential diagnosis of mixed infection of duck hepatitis A virus type 1 and type 3 in ducklings

Journal of Virological Methods ◽

10.1016/j.jviromet.2013.04.012 ◽

2013 ◽

Vol 192 (1-2) ◽

pp. 12-17 ◽

Cited By ~ 27

Author(s):

Lin-Lin Chen ◽

Qian Xu ◽

Rui-Hua Zhang ◽

Lei Yang ◽

Jing-Xin Li ◽

...

Keyword(s):

Differential Diagnosis ◽

Virus Type ◽

Mixed Infection ◽

Hepatitis A ◽

Hepatitis A Virus ◽

Rt Pcr ◽

Pcr Assay ◽

Duck Hepatitis ◽

Type 3

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Construction of Recombinant Lactococcus lactis Strain Expressing VP1 Fusion Protein of Duck Hepatitis A Virus Type 1 and Evaluation of Its Immune Effect

Vaccines ◽

10.3390/vaccines9121479 ◽

2021 ◽

Vol 9 (12) ◽

pp. 1479

Author(s):

Xiaoting Zhang ◽

Ruihua Zhang ◽

Jingyu Wang ◽

Nana Sui ◽

Guige Xu ◽

...

Keyword(s):

Immune System ◽

Fusion Protein ◽

Lactococcus Lactis ◽

Virus Type ◽

Hepatitis A ◽

Hepatitis A Virus ◽

Interleukin 2 ◽

Interleukin 4 ◽

Duck Hepatitis

With the continuous development of duck farming and the increasing breeding density, the incidence of duck hepatitis A virus type 1 (DHAV-1) has been on the rise, seriously endangering the development of duck farming. To reduce the use of antibiotics in duck breeding, susceptibility risks and mortality, and avoid virulence recovery and immune failure risk, this study aims to develop a new type of mucosal immune probiotics and make full use of molecular biology techniques, on the level of genetic engineering, to modify Lactococcus lactis (L. lactis). In this study, a secretory recombinant L. lactis named MG1363-VP1 with an enhanced Green Fluorescent Protein (eGFP) and translation enhancer T7g10L was constructed, which could express the VP1-eGFP fusion protein of DHAV-1. The animal experiment in ducklings was performed to detect the immune response and protection effect of oral microecologics by recombinant L. lactis. The results showed that oral L. lactis MG1363-VP1 significantly induced the body’s humoral immune system and mucosal immune system to produce specific anti-VP1 IgG antibodies and mucosal secretory immunoglobulin A (sIgA) for DHAV-1 in ducklings, and cytokines including interleukin-2 (IL-2), interleukin-4 (IL-4), interleukin-10 (IL-10), and interferon gamma (IFN-γ). The mortality rate was monitored simultaneously by the natural infestation in the process of production and breeding; notably, the ducklings vaccinated with L. lactis MG1363-VP1 were effectively protected against the nature infection of DHAV-1. The recombinant L. lactis MG1363-VP1 constructed in this study provides a new means of preventing and controlling DHAV-1 infection in the future.

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Duck Hepatitis A Virus Type 1 Induces eIF2α Phosphorylation-Dependent Cellular Translation Shutoff via PERK/GCN2

Frontiers in Microbiology ◽

10.3389/fmicb.2021.624540 ◽

2021 ◽

Vol 12 ◽

Author(s):

Yuanzhi Liu ◽

Anchun Cheng ◽

Mingshu Wang ◽

Sai Mao ◽

Xumin Ou ◽

...

Keyword(s):

Virus Type ◽

Hepatitis A ◽

Hepatitis A Virus ◽

Translation Efficiency ◽

Eif2α Phosphorylation ◽

Duck Hepatitis ◽

Cellular Translation ◽

First Time

Duck hepatitis A virus type 1 (DHAV-1) is one of the most deadly pathogens that endanger the duck industry. Most viruses usually turn off host translation after infection to facilitate viral replication and translation. For the first time report to our knowledge, DHAV-1 can induce eIF2α phosphorylation and inhibit cellular translation in duck embryo fibroblasts (DEFs). Moreover, the activity of DHAV-1 in the cells caused obvious eIF2α phosphorylation, which has nothing to do with the viral protein. Subsequently, we screened two kinases (PERK and GCN2) that affect eIF2α phosphorylation through inhibitors and shRNA. Notably, the role of GCN2 in other picornaviruses has not been reported. In addition, when the phosphorylation of eIF2α induced by DHAV-1 is inhibited, the translation efficiency of DEFs restores to a normal level, indicating that DHAV-1 induced cellular translation shutoff is dependent on eIF2α phosphorylation.

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