Cytokine gene expression in the livers of ducklings infected with duck hepatitis virus-1 JX strain

Poult Sci. 2012 Mar;91(3):583-91. doi: 10.3382/ps.2011-01743.

Abstract

Duck hepatitis virus type 1 (DHV-1) causes a highly contagious disease in ducklings and is often associated with liver necrosis, hemorrhages, and high mortality. In the current study, the expression levels of gene transcripts encoding proinflammatory cytokines and the virus were measured by quantitative reverse-transcription PCR in duck livers after infection with a DHV-1 JX isolate obtained from natural cases in Hubei Province, China. In addition, sera IL-1β, IL-6, and alanine aminotransferase levels were quantified. Liver histopathology was examined following DHV-1 infection. The ducklings died within 1 to 2 d postinfection (d.p.i.) because of typical liver degeneration, hemorrhage, necrosis, and bile-duct epithelial cell proliferation. Transcripts of the cytokines IFN-α, IL-6, TNF-α, and IL-10 decreased by 0.5 d.p.i. and then gradually increased at 1 d.p.i. Similarly, DHV-1 JX 3D gene levels in the liver sharply increased at 1 d.p.i. and then maintained a high level. In contrast, liver TNF-α and IL-1β transcripts showed no increased expression of the cytokine gene postinfection and significantly decreased compared with the expression at 0.25 d.p.i., only the expression of IFN-α transcripts increased 128-fold by 1 d.p.i. Changes in the serum IL-6 level remained relatively stable postinfection and not significantly different compared with that of the control (P > 0.05), whereas serum levels of IL-1β significantly decreased at 0.5 d.p.i. and increased from 1 d.p.i. onwards (P < 0.05). Serum alanine aminotransferase levels significantly increased 2 d.p.i. compared with that of the control group (P < 0.01), which seemed to keep with the number of dead ducks. The cytokines exhibited a biphasic pattern following DHV-1 JX infection. Taken together, the data indicated that duckling liver inflammatory responses were produced following experimental DHV-1 JX infection involving multiple cytokines.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alanine Transaminase / blood
  • Alanine Transaminase / immunology
  • Animals
  • Cytokines / biosynthesis*
  • Cytokines / genetics
  • Cytokines / immunology
  • Ducks*
  • Hepatitis Virus, Duck / genetics
  • Hepatitis Virus, Duck / immunology*
  • Hepatitis, Viral, Animal / genetics
  • Hepatitis, Viral, Animal / immunology*
  • Hepatitis, Viral, Animal / virology
  • Histocytochemistry / veterinary
  • Interferon-alpha / genetics
  • Interferon-alpha / immunology
  • Interleukin-10 / genetics
  • Interleukin-10 / immunology
  • Interleukin-1beta / genetics
  • Interleukin-1beta / immunology
  • Interleukin-6 / genetics
  • Interleukin-6 / immunology
  • Liver / immunology*
  • Picornaviridae Infections / genetics
  • Picornaviridae Infections / immunology
  • Picornaviridae Infections / veterinary*
  • Picornaviridae Infections / virology
  • Poultry Diseases / genetics
  • Poultry Diseases / immunology
  • Poultry Diseases / virology*
  • RNA / chemistry
  • RNA / genetics
  • Reverse Transcriptase Polymerase Chain Reaction / veterinary
  • Tumor Necrosis Factor-alpha / genetics
  • Tumor Necrosis Factor-alpha / immunology

Substances

  • Cytokines
  • Interferon-alpha
  • Interleukin-1beta
  • Interleukin-6
  • Tumor Necrosis Factor-alpha
  • Interleukin-10
  • RNA
  • Alanine Transaminase