A) Frequencies of BST2+ CD4 and CD8 T cells among PBMCs cultured overnight in presence or absence of different combinations of TLR9L, stimulating CD3-specific Ab (HIT3a) and stimulating CD28-specific Ab (CD28.2); medians and IQRs of experiments from N=6 independent donors are shown. B) Frequencies of BST2+ CD4 and CD8 T cells among PBMCs cultured overnight in presence or absence of TLR9L and/or stimulating CD3-specific Ab (HIT3a) and pre-treated or not with blocking antibodies against the subunit 2 of the IFN-α receptor (αIFNAR2) and/or against the subunit 1 of the IFN-γ receptor (αIFNGR1); each symbol represents results from one independent donor (N=3) for both CD4 and CD8 T cells (empty and solid symbols, respectively). C) IFN-α was measured by ELISA in supernatants from PBMCs cultured overnight in presence or absence of different combinations of TLR9L, HIT3a and CD28.2, pre-treated or not with the BST2-specific blocking Ab 26F8; medians and IQRs of experiments from N=6 independent donors are shown. In both panels, * P<0.05, ** P<0.01 compared to control.