FIG 6.

Effect of blocking Treg-inhibitory molecules on T cell responses to ex vivo VZV restimulation. (A) Proliferation. Data were derived from 31 adults, including 19 participants >70 years of age, 6 participants 60 to 70 years of age, and 6 participants 50 to 60 years of age. PBMC from day 42 after vaccination corresponding to peak memory responses were stimulated with live VZV vOKA (control), supplemented with either anti-CTLA4 mAb (CTLA4 block), anti-PD1 mAb (PD1 block), or anti-CD39 mAb (CD39 block). (B) IL-2 SFC measured by a FluoroSpot assay. Data were derived from 14 older adults. PBMC from day 42 after vaccination corresponding to peak memory responses were stimulated with the VZV lysate in growth medium (control) or growth medium supplemented with anti-CTLA4 mAb (CTLA4 block), with anti-PD1 mAb (PD1 block), or with anti-CD39 mAb (CD39 block). Horizontal bars indicate comparisons between control and treated conditions. **** indicates a P value of <0.0001, calculated with a Wilcoxon matched-pairs signed-rank test. *, P < 0.05 and ≥ 0.01; **, P < 0.01 and ≥ 0.001; ns, not significant.