Fixation1)Collect2X106cells.2)Pelletcellsbyspinningat1,000rpm,4°Cfor5minutes.3)ResUSPendcellpelletin1mlofcoldPBS.4)Fixcellsbyadding4mlof-20°Cabsoluteethanol.5)Storecellsat-20°Cinthisfixationbufferuntilreadyforanalysis.(Nomorethan2weeks)Staining6)Centrifuge(asabove)fixedcellsandresuspendpelletin1mlofPBS.7)Add100µlof200µg/mlDNase-free,RNaseAandincubateat37°Cfor30minutes.8)Add100µlof1mg/mlpropidiumiodide(lightsensitive)andincubateatroomtemperaturefor5-10minutes.9)Placesamplesin12X75FalcontubesandreadonBectonDickinsonFACSTarPLUS.