Figure 2.

Loss of an N-linked glycan at position 386 in primary HIV Envs enhances macrophage tropism and neutralization sensitivity to mAb b12. (A) MDM were infected with luciferase-expressing reporter viruses expressing wild-type or N386D mutant Envs. Cells were lysed 6 days post-infection and analyzed for luciferase activity. (B, C, D) Luciferase-expressing reporter viruses expressing wild-type or N386D mutant Envs were incubated with a range of concentrations of human mAb b12 (B), sCD4 (C), or a HIV-1 neutralizing patient serum (PS; D) 1 h prior to infection of Cf2 cells transiently expressing CD4 and CCR5. Cells were harvested 48 h post infection and assayed for luciferase activity. Data are expressed as the concentrations at which luciferase expression was reduced by 50% compared to infection in the absence of mAb (IC₅₀). Error bars represent standard deviations.