Figure 5

Sensitivity of brain and immune tissue envelopes to inhibition by soluble CD4, the CD4bs mab, b12 and the CCR5 antagonist maraviroc: The impact of macrophage tropism. A panel of 32 envelopes that represented the full range of macrophage-tropism observed for LN/spleen envelopes and included highly macrophage-tropic envelopes from the brain was tested for their sensitivity to sCD4, b12 and maraviroc using env+ pseudovirions. A. Brain envelopes were significantly more sensitive to sCD4 compared to those from immune tissues, but are not significantly more sensitive to maraviroc or the CD4bs mab, b12. B. Soluble CD4 sensitivity correlates with macrophage infectivity and is highly significant. There is a weaker correlation between b12 sensitivity and macrophage infection. Control envelopes JR-FL (mac-tropic) and JR-CSF (non-mac-tropic) are depicted as green and red spots respectively. C. Even when just LN/spleen envelopes are analyzed, there is a strong correlation between macrophage infection and sCD4 sensitivity as well as a weaker association with b12. This latter observation rules out the possibility that brain or LN/spleen founder effects affect the correlations shown.