Dual reporter lentiviral construct. Schematic diagram of the dual reporter, bidirectional lentiviral vector. LTR indicates long terminal repeat; RSV, respiratory syncytial virus; R, R element of retroviral LTR; U3, U3 element of retroviral LTR; ψ, packaging signal; RRE, rev response element; cPPT, central polypurine tract; bGH pA, bovine growth hormone polyadenylation signal; hPGK prom, human phosphoglycerate kinase-1 promoter; INS, insulator core derived from the chicken CHS4 element; N, nuclear factor of activated T cells (NFAT)-responsive enhancer; β, minimal human β-globin promoter; CBR Luciferase, click beetle red Luciferase; WPRE, woodchuck posttranscriptional regulatory element; pA, polyadenylation signal; and TATA, TATA box.