Kinetics of anti-Gag responses predicts viral load improvement and T helper activity. (A) Correlation analysis of viral load improvement versus slopes of anti-gp120 (left) and anti-p24 responses (middle) during cycles 1 to 4 (n = 46). (Right) Correlation analysis of viral load improvement versus timing of anti-p24 response. Weeks required to achieve a 2-fold increase over baseline were calculated by linear regression analysis and plotted versus viral load improvement (n = 42). (B) Patients were stratified for early and late anti-p24 responses according to the slope of titers measured during cycles 1 to 4. Early response: slope more than 0.01; late response: slope less than 0.01. Early and late groups were compared with respect to viral set points before ART and after STI and for viral load improvement using the Mann-Whitney test. (A-B) All significant observations were significant on the individual level and also after Bonferroni correction. (C) Correlation analysis of CD4 T helper responses at week 40 with maximum titer increases of anti-gp120 and anti-p24 responses. CD4 T helper responses depict the number of IFN-γ-producing, spot-forming cells per million CD8-depleted PBMCs in response to p24 stimulation as measured by ELISPOT (n = 21). The observation was only significant on the individual level. Significance was lost after Bonferroni correction (P > .025).