FIG. 6.

MAGI infectivities of virus stocks produced from CEM (12D-7) cells infected with VSV-G pseudotypes. HeLa cells were cotransfected with wt, KFS (env-minus), d8, 34VI, or 34VI/d8 molecular clones and a VSV-G expression vector. The VSV-G-pseudotyped virus stocks were normalized for RT activity and used to infect CEM (12D-7) cells. Two days postinfection, virus-containing supernatants were harvested, normalized for RT activity, and used to infect the MAGI cell line (19). Infected MAGI cells were fixed, stained, and scored 2 days postinfection. The infectivity of wt virus stocks was approximately 3 × 10⁴ infectious units/ml. Data presented are averages of at least two assays, ± standard deviations.