Use of Luciferase Reporter Viruses for Studying HIV Entry

HIV replication is classically measured by quantitating virus present in the supernatant of infected cells over time. Typically, cells are infected at low multiplicity of infection (MOI) and washed extensively to remove input virus. Samples of culture supernatant are then removed over approximately a two week period and frozen. Virus in the supernatants is then quantitated by reverse transcriptase assay or by ELISA for p24 ^gag antigen. Using live virus for studying virus replication is appropriate for many applications but has several drawbacks. Generating growth curves is relatively labor-intensive, requiring frequent sampling and passaging of the infected cultures. Input virus may be carried over and mistaken for virus production at early points in the growth curve. In addition, there is the biohazard associated with working with live virus.