NGF down-modulates A3G synthesis. Macrophages were treated with NGF (10 ng/mL unless otherwise indicated) alone or in combination with IFN-γ (10 ng/mL) for 48 hours. Cells were either lysed for immunoblotting (A,C) or RNA extraction and qRT-PCR were performed as described previously.30 (B). Alternatively, HIV-1–infected macrophages were treated with these molecules at the above-mentioned concentrations, and after 48 hours, cells were lysed, total DNA extracted, and the integrated HIV-1 LTR was sequenced. The phylogenetic relationship between the proviral DNA derived from these samples is presented in a tree rooted by the LTR sequence from the untreated HIV-1–infected cell (D). In panels A and C, representative immunoblots with their respective densitometries (A3G/β-actin) are displayed (n = 3). Data in panel B represent mean ± SEM of 3 independent experiments, **P < .01. In panel D, the bootstrap probability is indicated for each interior branch and the scale bar indicates the number of nucleotide changes per site.
