Levels of VEGF secreted by Tax-positive and -negative cell lines. (a) 293T cells were transfected with 1 μg of pCA-Tax1-HIS or pCA empty. Cells were incubated for 48 h, and VEGF was quantified in cell culture supernatants by ELISA. (b) A total of 1 × 106 cells each of the MT2 and C91 (HTLV-1 transformed), H2 (HTLV-2 transformed), TH, TE, CR (ATL cell lines), and CEM and Jurkat cells lines was cultured for 48 h, and VEGF protein in cell culture supernatant was quantified by ELISA.