Induction of antibodies against gp120 and p24. (A) Representative profiles of one patient with high (119) and one patient with low (106) rebound. Longitudinal VL measurements and antibody responses are depicted. Gray shaded areas indicate drug-free treatment periods. Viral load (log plasma VL) depicts the log HIV-plasma RNA copies per milliliter and is indicated in black. Anti-gp120 (red) and anti-p24 (green) titers are shown as reciprocal serum dilution that yielded 50% saturation. Autologous neutralization titers against the patient isolates derived at the beginning of the fifth-cycle reciprocal serum dilution that yield 70% inhibition (blue) are shown. (B) Longitudinal anti-gp120 (red) and anti-p24 (green) titer increases (Δ log) over baseline titers (weeks 0 to 2; cycle 1) were compared using 1-way ANOVA (Kruskal-Wallis test with the Dunn multiple comparison post testing) (n = 46 patients); short STIs (circles); long-term STIs (squares). Solid bars indicate mean values. (C) Correlation analysis of anti-gp120 versus anti-p24 responses. (Left) Analysis of baseline titers; (middle) maximum titers; (right) correlation of slopes of antibody titers measured during cycles 1 to 4. All significant observations were significant on the individual level and also after Bonferroni correction. n.s. indicates not significant. The solid line indicates the regression line, and the dotted lines indicate 95% confidence intervals.