Using a live/dead to remove dead cells can improve your staining. (a). Use of forward and side scatter gating (red rectangle) may not remove all dead cells and some non-specific binding may still be present. (b). Exclusion of dead cells using propidium iodide staining (red rectangle) means less non-specific binding and easier identification of positively stained populations. Images shown here are human peripheral blood stained with CD14 (MCA1568) and CD3 (MCA463).