Figure 1.

Coreceptor use profiles of SHIV Env proteins. Viral pseudotypes generated by cotransfection of env and NL-luc-E⁻R⁻ constructs into 293T cells were used to infect feline CCCS target cells expressing CD4 and indicated coreceptor. Infection of target cells leads to integration of the reporter virus genome and long terminal repeat-mediated production of luciferase, which was quantified in cell lysates 3 days after infection. Values were normalized to the level of infection of SHIV-4 with CXCR4 for each experiment. Experiments were performed ≥3 times by using at least two independently derived virus stocks. Error bars represent SEMs. HIV-1 JRFL is shown as a control for CCR5 expression.