A novel porcine gammaherpesvirus

Abstract

A novel porcine gammaherpesvirus was detected in the blood of domestic pigs by PCR. With degenerate-primer PCR and subsequent long-distance PCR approaches a 60-kbp genome stretch was amplified. Sequence analysis revealed the presence of the gammaherpesvirus ORFs 03 to 46 as well as a putative chemokine receptor and a v-bcl-2 gene. The 60-kbp sequence was compared with the corresponding sequence of the porcine lymphotropic herpesvirus 1 (PLHV-1) published recently and the sequence of PLHV-2, which was amplified from porcine tonsil. Considerable sequence differences (amino acid identities: 49-89%) were found between the novel virus and PLHV-1 as well as PLHV-2, which were very closely related to each other (amino acid identities: 85-98%). The novel virus had essentially the same genome organization as PLHV-1 and -2 and was therefore designated PLHV-3. Like PLHV-1 and -2, PLHV-3 was frequently found in the blood and in lymphoid organs of domestic and feral pigs from different geographic locations. In the blood, the PLHVs were detected predominantly in B-cells. Indication for latent as well as productive PLHV-3 infection was found in the porcine B-cell line L23. It can be concluded that the PLHVs are widespread and are likely to cause a persistent B-lymphotropic infection. Since PLHV-1 has been implicated in the development of porcine posttransplantation lymphoproliferative disease, all porcine lymphotropic gammaherpesviruses are of concern when pigs are used as donors in xenotransplantation.

Detection of a Second Novel Gammaherpesvirus in a Free-ranging Koala (Phascolarctos cinereus)

“…We previously reported the detection of PhaHV-1 in samples from three koalas (koalas A-C, Table 1) using a generic panherpes nested PCR targeting a conserved region of the herpesvirus DNA polymerase (DPOL) gene (Chmielewicz et al, 2003). Direct sequencing of the amplified PCR products showed that the DNA sequences were identical in each sample .…”

“…The unknown sequence (designated PhaHV-X) had 60% pairwise nucleotide identity with PhaHV-1 (GENEious software (http://www.geneious.com/)). To obtain additional PhaHV-X sequence, further PCRs were performed using the degenerative primer DFA paired with primers KG1 or IYG (Chmielewicz et al, 2003), or a reverse primer designed using available PhaHV-1 sequence (PhaHV-1.Rev 59TTCACAGAG-TCCGTGTCGCC93). These PCRs used template extracted from all koala samples that were PCR-positive for herpesvirus DNA .…”

Novel herpesviruses of Suidae: indicators for a second genogroup of artiodactyl gammaherpesviruses

“…The intergenic regions were 95 % identical. In contrast, the intraspecies nucleic acid identity of PLHV-3 was always more than 99?9 % in coding regions and more than 99?0 % in non-coding regions (Chmielewicz et al, 2003a). Furthermore, domestic pigs have only tested positive for PLHV-3 (Chmielewicz et al, 2003a).…”

“…Nucleic acid-based (Ehlers et al, 1999b;Chmielewicz et al, 2003a) and 178 bp (excluding primer binding sites) were obtained, the length depending upon the herpesvirus species. When novel sequences were detected, specific primer pairs were designed and retested in the suid species of origin.…”

“…Due to their lymphotropism, they were named porcine lymphotropic herpesviruses 1, 2 and 3 (PLHV-1, -2, -3). PLHV-1 and -3 and PLHV-2 have been found to be highly prevalent in domestic and feral pig populations, respectively (Ehlers et al, 1999b;Ulrich et al, 1999;Chmielewicz et al, 2003a). Evidence for the pathogenic potential of PLHV-1 was obtained using a porcine model of haematopoietic stem cell transplantation.…”