1 Max von Pettenkofer Institute for Medical Microbiology
and Hygiene, University of Munich, Germany.
2 Institute for Experimental Pathology and Therapy, Academy of Medical
Sciences, Primate Research Center Sukhumi, Georgia. 3Immunopathology
Laboratory, Department of Pathology, Karolinska Institute Stockholm,
Sweden.
+present address: Departments of Neurology, Biochemistry and Biophysics,
University of California, San Francisco, USA.
T-cell leukemia virus-like proviral sequences (STLV-I) as well
as EBV-like sequences were detected in PBLs and tissues of non-human
primates (Papio hamadryas baboons, Green monkeys and Macaca arctoides;
Sukhumi Primate Center/Georgia) by PCR. Surprisingly, two different
types of STLV-I within Papio hamadryas baboons were found. One of
it represents the baboon prototype STLV-I-Su described earlier,
present in lymphomatous baboons from the "highlymphoma stock", which
shows about 83% homology to HTLV-I and 85% to STLV-I in the env
and tax genes. The inter-individual variability within this subtype
is very low (about 1% in the tax gene) .The second subtype was mainly
found in asymptomatic animals from the control colony and showed
in the env gene 95% homology to HTLV-I, but only 82% to the prototype
baboon sequence. The presence of two subtypes within the Sukhumi
baboon population might be interesting in respect to the inoculation
experiments with human leukemic blood and to possible interspecies
transmissions.
The nature of the Herpes Papio-virus was elucidated as EBV-like
and the homology to the human EBV was >90% in the polymerase gene.
The homologies between different monkey species were between 92
and 96% and also here two subtypes within the baboons were detected.
This is the first direct demonstration by sequencing that the Herpes
Papio virus is closly related to EBV. For further studies of this
animal model, rabbits were inoculated with cells originated from
lymphomatous baboons and macaques. The rabbits developed generalized
lymphomas lethal within 1-2 months. EBV-like and STLV-I-like sequences
could be detected by PCR and sequencing showed 99-100% identity
to the inoculum, indicating in fact the transmission from monkey
to rabbit. These animal models seem to be very suitable for the
elucidation of the pathogenesis of human HTLV-I associated T-cell
leukemia/lymphoma and might be furtheron used for therapeutical
and preventative studies.
|