Influence of gene labeling in HIV-1 gag on viral infectivity and replication.

<p>A) Viral infectivity was assessed after transiently infecting HEK293T cells with the indicated viral plasmids, harvesting cells 72 h post transfection and using equal amounts of capsid-normalized virus particles to infect CD4-positive TZM-bl indicator cells. Luciferase activity (RLU) was measured in cells lysed 48 h post infection. The control represents uninfected cells. Error bars indicate the standard deviations from quadruplet infection. B) To monitor and maintain viral replication over a period of 20 weeks, CEM cells were infected in duplicate with virus-containing supernatants. Capsid protein (p24) amounts in culture supernatants were quantified by ELISA at the indicated time points. The control represents supernatant from an uninfected cell culture. Error bars indicate standard deviations from duplicate infections.