HTLV-I Tax-transactivated IL-9 expression in Jurkat T cells. (A) IL-9 mRNA levels after Tax induction were detected by Taqman real-time PCR. The copy number of IL-9 mRNA was normalized by the copy number of hypoxanthine guanine phosphoribosyl transferase 1 (HPRT1) mRNA. The data are representative of 3 independent experiments. (B) Western blot analysis using a monoclonal antibody to Tax for relative expression of wild-type HTLV-I Tax (JPX-9) and nonfunctional mutant Tax (JPX-m) in JPX-9 and JPX-m before and after addition of 20 μM CdCl₂. (C) Taqman real-time analysis of HTLV-I Tax and IL-9 message in ATL PBMCs ex vivo cells.