Figure 3.

SV40-based episomal copy number and gene expression in transiently transfected HT-1376 cells. (A) Densitometric analysis of data shown in Fig. 2. 107/402-T expression (▪) is presented on a relative scale, with 100% indicating the observed level at day 1. Copy number of episomes encoding wild-type T (○) or 107/402-T (•) is presented on a log scale. (B and C) Plotted are the relative levels of β-galactosidase (▪) and luciferase (•) expression in cells cotransfected with pRSVlacZII, pCMVint-lux, and either pRC/CMV.107/402-T or pRC/CMV, respectively. Gene expression is normalized for the day 1 value, which is considered to be 100%. Shown are means ± SE of three separate experiments. Significance was determined using a paired, one-tailed Student’s t test. ∗, P < 0.05; ∗∗ P < 0.01.