ROS produced by monocytes contribute to PVR expression on Ag-activated T cells. (A) CFSE-labeled PBMCs were immunodepleted or not depleted of CD14⁺ cells. Total PBMCs or CD14⁻ PBMCs were stimulated with SEB for 2 days and treated or not with H₂O₂ (100μM). Staining and FACS analysis were performed after an additional 24 hours on CFSE^low T cells, as described in the legend to Figure 3A. CD48 expression was analyzed as a control. Filled histogram shows the isotypic control mAb, and the black line shows PVR or CD48. PVR or CD48 MFI values subtracted from isotypic control mAb value are shown. (B) Mean values of MFI ± SD of PVR expression on total and CD14⁻ PBMCs treated or not with H₂O₂ (100μM) from 3 different donors tested. Statistical analysis was with the Student paired t test.