Assessment of HTLV-1 infection in rabbits. Rabbits were inoculated with 1 × 107 irradiated 729wtHTLV-1, 729HTLVRex-, or 729HTLVRex- + Rex (Table 1). At weeks 1, 2, 3, 4, 6, 8 after inoculation, rabbit PBMCs and sera were isolated from blood. (A) p19 Gag expression in the supernatant of ex vivo-cultured rabbit PBMCs. PBMCs were cultured ex vivo for 2 weeks, and p19 Gag in the culture supernatant was detected by ELISA. Results are the average of 2 rabbits for each cell line, indicating that only PBMCs from 729wtHTLV-1-inoculated rabbits produce detectable p19 Gag. Error bars indicate standard deviations. (B) HTLV-1-specific serologic response. Sera from inoculated rabbits were tested for reactivity to specific HTLV-1 proteins by Western blot. A representative rabbit from each group as indicated is shown with reactive viral proteins labeled on the left. Results indicate that only 729wtHTLV-1-inoculated rabbits are seropositive. (C) Detection of HTLV-1-specific sequences in rabbits. Genomic DNA was isolated from rabbit PBMCs and subjected to PCR using HTLV-1-specific oligonucleotide primers. A representative result from one rabbit in each group is shown. Viral DNA integration was only detected in wtHTLV-1-inoculated rabbits.
