Blockade of CD95-CD95L interactions, TGF-β, or IL-10 does not restore the inhibition of T-cell stimulation by HCMV-infected mature moDCs. (A) Allogeneic T cells were preincubated with CD95 antagonist Ab (ZB4, 2.5 μg/mL), agonist Ab (CH11, 1 μg/mL), or both Abs successively. Controls included isotype-matched, nonreactive Abs in the same concentrations. Abs were added again during the MLR at days +2 and +4. Blockade of the CD95/CD95L interaction did not restore the immunostimulatory capacity of infected moDCs in the allogeneic MLR. (B) Allogeneic T cells were preincubated with a mixture of Abs blocking IL-10R-α (15 μg/mL), IL-10R-β (50 μg/mL), and TGF-β (10 μg/mL). Controls included a mixture of isotype-matched nonreactive Abs in the same concentrations or medium alone without Ab. Blocking IL-10 and TGF-β did not restore the immunostimulatory capacity of infected moDCs toward allogeneic T cells in the MLR. Note that the y-axes use log₂ scales to depict T-cell proliferation based on 3HTdR incorporation (cpm) during the last 8 to 12 hours of a 5-day alloMLR culture. (C) Positive controls using noninfected moDCs confirmed the appropriate activity of the mAbs used in panels A and B. Error bars indicate SD.