Time course of the animal experiments.

In a pilot experiment, the animal Mm5574 received 2 transfusions (Tr1 and Tr2) of autologous T cells at a 10-week interval. At necropsy (N) in week 25, pathological changes were not observed. Subsequently, the animals Mm7067, Mf6311, Mf6490, and Mf6698 received a first autologous transfusion (Tr1) and then a second transfusion (Tr2) after 20 weeks. At week 55, these animals and 2 naive control monkeys (Mf406 and Mf409) were subjected to intravenous challenge infection (Inf). Whereas the control animals died within 2 weeks from peripheral T-cell lymphoma, the other animals survived without pathological changes at necropsy at week 68. In 2 cases, the transformed T cells were successfully recultivated from peripheral blood, as indicated by (R). The results of virus isolation assays (V) and DNA-PCR (P) from peripheral blood leukocytes are summarized as follows: open squares indicate negative results and filled squares represent positive results for virus isolation (V) or PCR detection (P), respectively. While infectious virus was rarely isolated from peripheral blood, virus DNA was detectable in peripheral blood cells for long periods.