Is HHV-6 a Human and Porcine Virus?
http://vir.sgmjournals.org/content/80/4/971
Abstract
Evidence for the existence of porcine
gammaherpesviruses was obtained by PCR and sequence analysis. Initially,
samples of
peripheral blood mononuclear cells (PBMC), spleens,
lungs, kidneys and livers of pigs from Germany and Spain were tested
with
a PCR assay which targets conserved regions of the
herpesvirus DNA polymerase gene with degenerate and
deoxyinosine-substituted
primers. Amplicons of identical sequence were
obtained from one spleen and two PBMC samples. This sequence showed a
high percentage
of identity with the DNA polymerase genes of
herpesviruses of the oncogenic subfamily Gammaherpesvirinae. Alignment
of amino
acid sequences showed the highest identity values
with bovine gammaherpesviruses, namely alcelaphine herpesvirus type 1
(68%),
ovine herpesvirus type 2 (68%) and bovine
lymphotropic herpesvirus (67%). Comparison with pseudorabies virus and
porcine cytomegalovirus,
which are the only porcine herpesvirus species
presently known, showed values of only 41%. PCR analysis of PBMC (n =
39) and
spleen (n = 19) samples from German pigs, using
primers specific for the novel sequence, revealed a prevalence of 87 and
95%,
respectively. In this analysis, three out of eight
spleen samples from Spanish pigs were also positive. Subsequent
sequencing
of the amplicons revealed the presence of two
closely related gammaherpesvirus sequences, differing from each other by
8%
at the amino acid level. The putative novel porcine
herpesviruses, from which these sequences originated, were tentatively
designated porcine lymphotropic herpesvirus type 1
and type 2 (PLHV-1 and PLHV-2). When using pig organs for
xenotransplantation,
the presence of these viruses has to be considered.
