Extended Data Fig. 9: Dual CTLA-4/PD-1 blockade does not control or delay viral rebound after ATI.

The delay in viral rebound by ICB was analyzed as the average number of days until detectable viral loads were observed in plasma with RT-qPCR. Plasma viral loads following ATI are shown for individual RMs by ICB: (b) control, (c) αCTLA-4, (d) αPD-1, (e) combined blockade, and (f) BsAb. Mamu-A^*01⁺ RMs are shown with a bold connecting line and animals with prior ICB-related viral reactivation in plasma are represented as closed data points. The dotted horizontal line indicates the PCR assay limit of detection, with undetectable events plotted as 30 copies/mL. (g) Plasma viral loads following ATI were averaged by ICB and are shown with the mean as the solid line in bold and the s.e.m. represented by the color-matched shaded region. (h) The attenuation in set-point plasma viremia was analyzed between chronic infection (d52 p.i.) and following rebound (d170 post-ATI, p.A.). Population sizes are as follows for all viral load and rebound delay analyses: controls (n=6), black; αCTLA-4 (n=6), blue; αPD-1 (n=6), pink; combined blockade (n=7), red; and BsAb (n=8), purple. (i) By 12 replicate reaction RT-qPCR, the number of cell-associated SIV-RNA copies per 10⁶ cells was quantified in axillary LN at necropsy: controls (n=6), αCTLA-4 (n=6), αPD-1 (n=5), combined blockade (n=6), and BsAb (n=7). Averaged data are presented as the mean ± s.e.m., and were analyzed with a two-sided (g) two-way ANOVA with Dunnett’s correction for multiple comparisons or (a,h,i) a Mann-Whitney U test and/or Wilcoxon ranked sign test. Color-coded statistical asterisks indicate significance between control animals and the treatment group of that color. *, p<0.05; **, p<0.01; ***, p<0.001; ****, p<0.0001.