Phenotypic characterization of T cells after activation.

Human PBLs were stimulated with PHA and cultured for 1 to 5 days in the absence or presence of RBCs, as indicated. Activated T cells were stained with FITC- or RPE-conjugated antibodies against CD69, CD25, CD71, HLA-DR, and unlabeled anti-CD95, followed by FITC-conjugated rabbit-antimouse immunoglobulins. Labeled cells were acquired in a FACSort and analyzed using the Lysis II program. Histograms show results of resting PBL (day 0) and activated (day 5) T cells for all markers except CD69, for which day 1 is shown. Data are representative of 3 separate experiments.