Jf. Modiano et al., RETROVIRUS-LIKE ACTIVITY IN AN IMMUNOSUPPRESSED DOG - PATHOLOGICAL AND IMMUNOLOGICAL FINDINGS, Journal of Comparative Pathology, 112(2), 1995, pp. 165-183
A putative retrovirus was isolated from a dog with a severe, acquired
immunodeficiency-like syndrome. The haematological abnormalities and i
mmunological deficiencies included anaemia, leucopenia (lymphopenia an
d neutropenia), thrombocytopenia, decreased humoral immunity, and inef
fective T-cell responses in-vitro. The necropsy findings included gene
ralized lymphoid depletion, severe bone marrow hypoplasia, plasmacytic
infiltrates in lymphoid and non-lymphoid organs, and severe secondary
infections. Supernates of peripheral blood mononuclear cell cultures
from the affected dog contained an agent with manganese-dependent reve
rse transcriptase (RT) activity that sedimented at a density of 1.122
g/ml. RT activity was also found post-mortem in extracts prepared from
the bone marrow, lymph nodes, and small intestine. The lymph nodes an
d small intestine expressed a 3.8 kb mRNA that was recognized by a bov
ine leukaemia virus (BLV) pol DNA probe by Northern blotting. DNA isol
ated from the lymph nodes and small intestine from the affected dog sh
owed distinct band patterns by Southern analysis, suggesting an exogen
ous retrovirus. The retrovirus could be propagated in normal canine pe
ripheral blood mononuclear cells or short-term canine lymphocyte cell
lines in-vitro, and was cytopathogenic for cells of canine, but not hu
man, origin. These results suggest the existence of a pathogenic canin
e retrovirus capable of producing disease of the type associated with
retroviruses in other species.