Figure 1.

HIV RNA and DNA can be detected in AMs despite low T-tropic HIV entry and replication rates. (A) HIV Gag RNA and DNA are detectable in alveolar macrophages (AMs) from individuals with untreated HIV infection. HIV Gag RNA or DNA copies per cell by qRT-PCR in AMs from the Cape Town cohort. Dashed lines denote the limit of detection for the assay, and negative values are plotted at 50% of the limit of detection. (B, C) Viral entry was detected in AMs and BAL CD4+ T cells from HIV-uninfected subjects using gravity infection for 12 h with a BLaM-Vpr construct (HIV+) of JR-CSF (B) or 89.6 (C) or mock infection (HIV-) at a multiplicity of infection (MOI) of 1. HIV entry was detected by cleavage of a fluorescent BLaM substrate and measured by flow cytometry; n = 6. (D, E) CD4+ T cells, MDMs and AMs were infected with replication-competent JR-CSF (D) or 89.6 (E) at a MOI of 0.2 for 12 h. HIV p24 levels in the supernatant were measured by ELISA at the indicated time points and normalized to input at day 1; n = 11 for T cells, n = 12 for MDMs, and n = 6 for AMs. Statistics were done by Kruskal–Wallis tests with Dunn’s multiple test correction in B and C. *p < 0.05, **p < 0.01, ***p < 0.001.