Figure 2.

Expression of a nonsecretory protein via an adenovirus vector does not alter the synthesis or the polarized secretion of VEGF and TGF. RPE-J cells grown on porous filter supports were transduced with AdVEGF (A and B) or AdTGF (C and D) at mois estimated from Fig. 1 to result in an ≈80% apical secretion of the gene product. Sixteen hours later, the cells were transduced with AdCMV-LacZ, expressing the β-galactosidase gene, at mois between 0 and 300. Eight hours later, the media were changed. After 14–16 h, the media and the cells were assayed for VEGF or TGF. Increasing mois of AdCMV-LacZ as assayed by β-galactosidase activity (▴-▴) had no effect on the polarized secretion or secretion levels of VEGF (A and B) or TGF (C and D). In A and C, the results from four separate experiments are shown as mean ± SEM. B and D are representative experiments. Dark bars, apical secretion; light bars, basal secretion.