Toll-like receptor activation and expression in bovine alpha-herpesvirus infections

Res Vet Sci. 2014 Feb;96(1):196-203. doi: 10.1016/j.rvsc.2013.11.015. Epub 2013 Dec 18.

Abstract

The involvement of Toll-like receptors (TLRs) in bovine herpesvirus types 1 (BoHV-1) and 5 (BoHV-5) infections has not been analyzed. In this study, the role of TLR signaling on virus replication was investigated. Blood leukocytes consistently express TLRs. Thus, our approach was to study in vitro the effects of agonist stimulation of TLRs expressed by peripheral blood leukocytes on BoHV-1 and BoHV-5 replication. Furthermore, the patterns of TLRs 3, 7-9 expression on virus-infected-bovine leukocytes were analyzed. Only Imiquimod (TLR7/8 agonist) showed anti-viral activity on infected MDBK cells. This is the first evidence that the timely activation of TLR7/8 signaling is effective in impairing BoHV-1 and 5 replication, thereby providing an experimental indication that Imiquimod may be a promising immune modulator. This work describes, for the first time, the expression patterns of TLRs in BoHV-1- or BoHV-5-infected-bovine leukocytes, suggesting the involvement of TLR7 and TLR9 in the recognition of these viruses.

Keywords: Agonist; Bovine herpesvirus; Expression patterns; Toll-like receptor.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aminoquinolines / pharmacology*
  • Aminoquinolines / therapeutic use
  • Animals
  • Cattle
  • Cattle Diseases / immunology
  • Cattle Diseases / virology*
  • Cell Line
  • Herpesviridae Infections / drug therapy
  • Herpesviridae Infections / immunology
  • Herpesviridae Infections / veterinary*
  • Herpesviridae Infections / virology
  • Herpesvirus 1, Bovine / immunology*
  • Herpesvirus 5, Bovine / immunology*
  • Imiquimod
  • Least-Squares Analysis
  • Leukocytes, Mononuclear
  • RNA, Viral / chemistry
  • RNA, Viral / genetics
  • Reverse Transcriptase Polymerase Chain Reaction / veterinary
  • Signal Transduction / immunology
  • Toll-Like Receptors / agonists
  • Toll-Like Receptors / immunology*
  • Virus Replication / immunology

Substances

  • Aminoquinolines
  • RNA, Viral
  • Toll-Like Receptors
  • Imiquimod