PI susceptibility and single round infectivity of patient Gag-Protease derived pre-PI therapy and at the time of treatment failure.

<p>Full-length Gag-Protease from pre-PI therapy and failure time-points was amplified or synthesised, and cloned into our Gag-Pol expression vector p8.9NSX+. PI susceptibility of VSV-g pseudotyped viruses from patients experiencing virological failure in the absence of major resistance mutations was measured in a cell-based, single-round, phenotypic assay to the PIs A) Lopinavir (LPV) and B) Darunavir (DRV). The patient numbers are shown for each data point and data are means of two independent repeats. Our data demonstrate no significant difference in susceptibility between pre-PI therapy and failure viruses to the PIs LPV (t test, p = 0.91) and DRV (t test, p = 0.78), in patients failing in the absence of major resistance mutations. (C) Single-round infectivity of viruses was measured in the absence of drug in HEK 293T cells and compared in patients failing without major resistance mutations. No significant decrease in single-round infectivity was present (t test, p = 0.07).