Figure 3. Human peripheral lymphocytes were stained with anti-CD3 and various fluorophore-conjugated secondary antibodies, and were analyzed in a FACS Caliber flow cytometer (Becton Dickinson). DyLight 488 (green)-, FITC (yellow)-, and Cy2 (blue)-conjugated secondary antibodies were from Jackson ImmunoResearch. A comparable secondary antibody conjugated with Alexa Fluor 488 was purchased from Molecular Probes, Inc. The arrow indicates a slight background with the Alexa Fluor 488 conjugate in this experiment.