r-hTRX/ADF is produced by DNA recombinant procedure in E. Coli as an intracellular protein. In the search for a possible mechanism of interleukin 2 receptor ?-chain (IL-2R?)/p55 (Tac) induction in adult T cell leukemia (ATL), a soluble factor responsible for this receptor abnormality was discovered by Teshigawara et al. The factor called ATL-derived factor (ADF) enhanced the IL-2R? expression on some lymphocytes. After gene cloning, ADF
12 kDa in SDS-PAGE analysis