Titration of infectivity of single-cycle and replication-competent HIV-1 stocks.

aSingle-cycle, VSV-G-pseudotyped luciferase reporter HIV-1 Vpr+, HIV-1 Vpr−, and Vpr complemented HIV-1 Vpr− stocks. The data represent average results of duplicated samples from two independent experiments.bSingle-cycle, MLV amphotrophic (Ampho) envelope-pseudotyped luciferase reporter HIV-1 Vpr+ and HIV-1 Vpr− virus stocks.cReplication-competent HIV-1NLAD8(WT) and HIV-1NLAD8(ΔVpr) stocks. All viral stocks were prepared from HEK293T cells and analyzed for p24 concentration by ELISA. The infectivity of each virus stock was evaluated on HIV-1 indicator GHOST/R5 cells by a limiting dilution assay [35]. The relative infectivity of each virus stock is presented as the number of infectious units (IU) per 1 ng of p24.