Sensitivity vector metrics further illuminate the phenotype of well-characterized point mutants. (A) Infectivity profile of wt JR-CSF (R5) envelope, and three point mutants: (B) S142N, (C) E153G and (D) K421D, previously shown to enhance or perturb CCR5 or CD4 usage with polar plots (beneath) representing the metrics obtained from mathematical analysis of the infectivity profiles (A-C). The vector angle (θ) is the angle between the x-axis and the dotted line. The vector amplitude (Δ) is represented by the length of the dotted line. The mean infectivity (M) is represented by the size of the circle. Data shown is a representative of two experiments. (E) Table of the average Affinofile metrics obtained from (A-D) and graphically shown in polar plots beneath (A-D). Boxes next to (E) describe the phenotypes indicated by each metric relative to wt JR-CSF. The infectivity profile of each Env was independently repeated twice.