CCL3 and viral chemokine-binding protein gg modulate pulmonary inflammation and virus replication during equine herpesvirus 1 infection

J Virol. 2008 Feb;82(4):1714-22. doi: 10.1128/JVI.02137-07. Epub 2007 Dec 12.

Abstract

CCL3 is a proinflammatory chemokine that mediates many of the cellular changes occurring in pulmonary disease. Here, CCL3(-/-) mice were used to investigate the role of this chemokine during respiratory herpesvirus infection. Compared to wild-type mice, CCL3(-/-) mice infected with the alphaherpesvirus equine herpesvirus 1 (EHV-1) displayed reduced body weight loss but had higher pulmonary viral loads. Lungs from infected CCL3(-/-) mice suffered a milder interstitial pneumonia, and fewer immune cells were recovered from the pulmonary airways after infection. We could also demonstrate that herpesvirus-encoded chemokine-binding glycoprotein G (gG) was capable of inhibiting the chemotactic functions of CCL3. This CCL3-mediated chemotaxis, however, was restored in the presence of gG-specific antibodies, which puts into question the advertised use of gG deletion mutants as marker vaccines. In summary, we concluded that CCL3 is a major player in controlling herpesvirus replication in the target organ, the lung, and does so by evoking a strong inflammatory response. The immunomodulatory activity of CCL3 is balanced by the expression of viral gG, whose chemokine-binding activity is mitigated in secondary infections by the production of anti-gG antibodies.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies, Viral / immunology
  • Chemokine CCL3 / genetics
  • Chemokine CCL3 / metabolism*
  • Herpesviridae Infections / genetics
  • Herpesviridae Infections / immunology*
  • Herpesviridae Infections / pathology
  • Herpesvirus 1, Equid / physiology*
  • Mice
  • Mice, Knockout
  • Pneumonia, Viral / genetics
  • Pneumonia, Viral / immunology*
  • Pneumonia, Viral / pathology
  • Viral Envelope Proteins / antagonists & inhibitors
  • Viral Envelope Proteins / metabolism*
  • Viral Load
  • Virus Replication*

Substances

  • Antibodies, Viral
  • Chemokine CCL3
  • Viral Envelope Proteins
  • glycoprotein G, Equid herpesvirus 1