RBCs reduce ROS production in activated human T cells.

Resting human PBLs were labeled with 100 μM DCFH-DA as indicated in “Materials and methods.” T cells were left unstimulated or were activated with PHA-P (5 μg/mL) in CM in the absence (PHA) or presence (PHA+RBC) of RBCs for 24 hours. After harvesting, duplicates of the cell cultures were treated with lysis solution or were left untreated and were subsequently stained with CD3-RPE, and labeled cells were acquired in a FACSort. Dot blots show FSC versus CD3 staining in cultures treated with lysis solution and in nontreated cultures. Histograms show DCF fluorescence on gated CD3⁺ T cells in both conditions. The decrease in DFC mean fluorescence intensity in the presence of RBCs was statistically significant according to K/S statistics (D/s(n) = 39.07).