Overexpression of HIAP-1 in HTLV-1–infected human T-cells. HIAP-1 and Tax expressions were analyzed in HTLV-1–transformed T-cell lines (C91-PL and MT-2), ATL-derived cultures (Champ, StEd, ATL-3, and JuanaW), HAM/TSP-derived cultures (Eva), in uninfected ALL-derived CD4⁺ control T-cell lines (CCRF-CEM, Molt-4, and Jurkat), and in PBLs isolated from 3 healthy donors (PBL1-PBL3). (A) Total RNA was extracted and subjected to RT-PCR analyses. Equal loading was controlled by β-actin RT-PCR. (B) The same cDNAs were used for real-time RT-PCR analyses of HIAP-1, Tax, and β-actin (internal standard) transcripts. The relative mRNA copy numbers of HIAP-1 and Tax mRNA were determined as multiples of the β-actin mRNA copy number. The columns represent the mean of 6 experiments; the error bars, mean error. (C) To detect HIAP-1 protein, immunoblots were stained using HIAP-1–and β-actin–specific monoclonal antibodies.