Figure 12. Human peripheral lymphocytes were stained with anti-CD3 and various fluorophore-conjugated secondary antibodies, and were analyzed in a FACS-Calibur (Becton Dickinson) flow cytometer. DyLight 649 (green)-, APC (yellow)-, and Cy5 (blue)-conjugated secondary antibodies were from Jackson ImmunoResearch. A similar secondary antibody conjugated with Alexa 647 (red) was purchased from Molecular Probes, Inc. Notice the slight background at arrow in this experiment with the Alexa 647-secondary antibody.