Involvement of toll-like receptors 3 and 7/8 in the neuropathogenesis of bovine herpesvirus types 1 and 5

RENSETTI, D; MARIN, M; QUINTANA, S; MORÁN, P; VERNA, A; ODEÓN, A; PEREZ, S. E

RESEARCH IN VETERINARY SCIENCE

ELSEVIER SCI LTD

Lugar: Amsterdam; Año: 2016 vol. 107 p. 1 - 7

0034-5288

Bovine herpesvirus types 1 (BoHV-1) and 5 (BoHV-5) areclosely related alpha-herpesviruses. BoHV-5 is the causal agent of non-suppurativemeningoencephalitis in calves. BoHV-1 causes respiratory disease, abortions, genitaldisorders and, occasionally, encephalitis in cattle. Both viruses areneurotropic and they share similar biological properties. Nevertheless, theydiffer in their ability to cause neurological disease. Toll-like receptors(TLRs) are involved in the innate immune response to pathogens. In this study,the variations in the expression levels of TLRs were evaluated in differentregions of the bovine central nervous system during the acute infection andreactivation of BoHV-1 and BoHV-5- infected cattle. With the exception of TLR9,significant up-regulation of all TLRs was detected following primary infectionof neural tissues by both bovine alpha-herpesviruses. Furthermore, the stagesof acute infection and reactivation were characterized by a distinguishable TLRexpression pattern. Important differences in TLRexpression upon infection of the central nervous system by BoHV-1 or BoHV-5were not detected. The striking differences in TLR mRNA levels during acuteinfection and reactivation provide evidence that the innate immune response maybe involved in the clinical outcomes observed at each stage. Further researchis required to analyze the mechanisms that initiate TLR activation and thesignaling cascade mediated by each TLR to elucidate the precise role thesereceptors play in bovine herpesvirus encephalitis.