Figure 1: Lentiviral vector constructs and expression of transgenes in HEK293 cells. Panel A: HIV-1 based self-inactivated vectors using the CMV promoter to drive the expression of EGFP alone (HIV-CMV-EGFP), FPR-EGFP fusion protein (HIV-CMV-FPR-EGFP) or two independent proteins (FPR and EGFP) through an internal ribosomal entry site (HIV-CMV-FPR-IRES2-EGFP). iHEK293 cells were transduced with HIV-CMV-EGFP (B), HIV-CMV-FPR-EGFP (C) or HIV- CMV-FPR-IRES2-EGFP (D). i Cytosolic calcium responses of HEK293 cells, expressing EFPG alone (Green line), FPR-EGFP fusion protein (Red line) or the two separate proteins (FPR and EGFP) (Blue line), to N-formyl peptide stimulation.