Figure 4From: Lentiviral vector design using alternative RNA export elementsSchematic and viral titer of different lentiviral vector packaging constructs. Lentiviral vectors were produced using different transfer plasmids containing RRE (Fig. 4A) or multiple copies of SRV-1 (Fig. 4B) or MPV CTE (Fig. 4C). Viral titer was determined by end-point dilution using X-gal stained HeLa cells and p24 Gag protein ELISA. HATCHED bars = Kozak sequence (CCACCATGG); W = woodchuck post-regulatory element; C = constitutive transport element; pA = bovine growth hormone poly(A) signal; RRE = rev-responsive element; SD = splice donor; SA = splice acceptor. * p < 0.05 difference between lentiviral vectors produced with or without the rev protein.Back to article page