Effect of Tax transfection on VEGF promoter activity and secretion.

(A) VEGF-Luc or HTLV-I LTR-Luc constructs in pGL-2 corresponding to the luciferase gene under the control of the VEGF promoter or the HTLV-I promoter, respectively, was cotransfected into Jurkat cells with the internal control PSV β-galactosidase and either pCMV-Tax or empty vector. Luciferase activity was quantified 24 hours later and was normalized with the β-galactosidase activity. (B) HeLa cells were transfected with pCMV-Tax or empty vector. Levels of VEGF in the cell supernatant were measured using a commercial ELISA kit.