FIG 3.

Induced specific Treg phenotypes. (A) Representative flow cytometry dot plots showing the frequencies of activated CD134⁺ CD4⁺ T cells observed poststimulation with either HCMV lysate or with HHV-6A/HHV-6B lysates and their respective negative controls (unstimulated or mock lysates). (B to D) Gating strategy used to identify the frequencies of Treg subsets defined with the expression of CD127^low CD25^high (B), CD45RA⁻ Foxp3^high (C), and CD15s⁺ Foxp3^high (D) effector Tregs (eTregs). Their respective frequencies are summed up for HCMV (•) or HHV-6-induced (HHV-6A, ○; HHV-6B, ♦) specific Tregs. Each symbol represents an individual donor, and horizontal bars indicate the medians. (E to G) P values were calculated using the Wilcoxon pair test for group comparisons. Correlations between the frequency of IFN-γ-secreting effector T cells and the frequency of induced eTregs specific for either HCMV (•) (E), HHV-6 (HHV-6A, ○; HHV-6B, ♦) (F), or pooled specificities (HCMV and HHV-6) (G). The correlation coefficients were derived from Spearman analyses.