Time course analysis of IAb transcription in vivo. A, RT-PCR analysis of IAb and control CD2 gene transcription in tissues from long-term tolerant CBA #13 (POD 176). Proviral IAb sequences were detected by annealing to a [32P]-IRES–specific oligonucleotide. B, IAb transgene transcription in PBMCs, lymph nodes (LN), spleen, and thymus. Two rejector IAb-CBA (Rej; tested 11 wk after BMC infusion) and six long-term tolerant IAb-CBA (Tol; 30–32 wk) mice were monitored by RT-PCR for proviral IAb transcription. *Number of animals positive for IAb/number tested. Rej, rejector IAb-CBA mouse; Tol, long-term tolerant IAb-CBA mouse.