Vpx-treatment increases the intracellular dNTP pool in DCs. Monocyte-derived DCs treated with SIVmac VLPs with and without Vpx were collected at 0, 12, and 24 hours post VLP treatment. (A) The intracellular dNTP pool of VLP-transduced DCs was measured using the single nucleotide incorporation assay. The data show results of DCs from two independent healthy donors. Error bars represent standard deviation of the mean of duplicate samples. The asterisks indicate a significant difference (p <0.001) compared with the (Vpx -) controls at 24 hr post VLP-transduction. (B). A representative HIV-1 RT-based single nucleotide primer extension gel is shown for dATP extension for both donors. Reactions (+/−) RT were used to indicate unextended primer (P) versus and extended primer (P+1). Vpx(+) VLP treated samples at 24 hr were diluted 1:3 to prevent complete primer extension and maintain results within the linear range for quantification purposes.