| Abstract: | Orf virus (ORFV), a member of parapoxvirus, is an enveloped virus with genomeof double-stranded DNA. ORFV causes contagious pustular dermatitis or contagious ecthymain sheep and goats worldwide. In general, detection of viral DNA and observing ORFV virionin tissues of afflicted animals are two methods commonly used for diagnosis of orfinfection; however, isolation of the ORFV in cell culture using virus-containing tissue asinoculum is known to be difficult. In this work, the ORFV (Hoping strain) isolated incentral Taiwan was successfully grown in cell culture. We further examined the biochemicalcharacteristic of our isolate, including viral genotyping, viral mRNA and proteinexpression. By electron microscopy, one unique form of viral particle from ORFV infectedcellular lysate was demonstrated in the negative-stained field. Moreover, immunomodulatingand anti-influenza virus properties of this ORFV were investigated. ORFV stimulated humanmonocytes (THP-1) secreting proinflammatory cytokines IL-8 and TNF-α. And, pre-treatmentof ORFV-infected cell medium prevents A549 cells from subsequent type A influenza virus(IAV) infection. Similarly, mice infected with ORFV via both intramuscular andsubcutaneous routes at two days prior to IAV infection significantly decreased thereplication of IAV. In summary, the results of a current study indicated our Hoping strainharbors the immune modulator property; with such a bio-adjuvanticity, we further provedthat pre-exposure of ORFV protects animals from subsequent IAV infection. |
