FIG. 4.

Resistance to retroviral infection is specific to the MLV core. (A) Cells (1 × 10⁴/well of a 96-well plate) of the indicated cell lines were infected with either 5 × 10⁴ IU (LTU) of MMP-nls-lacZ[VSV-G] or 5 × 10⁴ IU of a VSV-G-pseudotyped HIV-1 vector that encodes β-galactosidase (Lenti6/V5-GW/lacZ [VSV-G]) and assayed 48 h postinfection with chemiluminescent assays for β-galactosidase and for viable cells as described for Fig. 2. (B) Cells (1 × 10⁴/well of a 96-well plate) of WT CHO-K1 or the indicated cell lines engineered to express TVA800 were infected with either 5 × 10⁴ IU (LTU) of the MLV vectors MMp-nls-LacZ[VSV-G], 5 × 10⁴ IU of pMMp-nls-LacZ[envA], or the ASLV-A vector RCASBP(A)-AP and assayed 48 h postinfection with chemiluminescent assays for cell viability and either β-galactosidase or alkaline phosphatase. TVA-expressing cell lines are designated with a T after the line name. The data shown are the average mean values obtained in an experiment with quadruplicate samples and are representative of results of three independent experiments. Error bars indicate the standard deviations of the data.