Figure 2

Role of the WPRE on β-gal protein expression in cell lines following lentiviral vector transduction. Canine (MDCK; Fig. 2A) and murine (RAG; Fig. 2B) immortalized cells were transduced with lentiviral vectors in the presence and absence of the WPRE in the transfer plasmid. The lentiviral transfer plasmid used in this experiment was the pHRSVcPGKnlsLacZS1.4(+) and pHRSVcPGKnlsLacZS1.4(+)W(+). The MDCK (MOI 3) and RAG (MOI 1) were transduced with the VSV-G pseudotyped lentiviral vectors and 48 hours later, the proteins were isolated and assayed for β-gal protein by ELISA. C = central polypurine tract sequence; PGK = murine phosphoglycerokinase promoter; nlsLacZ = nuclear localized lacZ gene; S1.4(+) = 4 copies of the SRV-1 CTE; W(-) = no WPRE; W(+) = WPRE. n = 3–5 different samples/lentiviral preparation. * p < 0.01 difference between the different groups.