Hi Stephen... We routinely do FITC, PE and APC immunophenotyping with 7-AAD at 5 ug/ml as a viability indicator. We also have a cell death assay using Oncoimmunin's PhiPhiLux G1D2 (which emits around the FITC range), a PE-conjugated antibody, 7-AAD and APC-annexin V all simultaneously. Unlike PE-Cy5, 7-AAD has almost no crossbeam interference issues with APC. We can run both assays on either our Vantage with a HeNe laser or Calibur with the red diode with no crossbeam compensation between 7-AAD and APC. We DO, however, notice some mild quenching of the PE signal with 7-AAD present, particularly at higher 7-AAD concentrations (such as those needed for DNA cell cycle). Not a big problem, but you should watch out for it. I don't have a good explanation for why it happens (perhaps some sort of energy transfer). Hope this helps. Bill ________________ Bill Telford, Ph.D. NCI MB Flow Cytometry Core Laboratory National Cancer Institute National Institutes of Health Bethesda, MD At 06:30 PM 1/17/00 -0500, Fang-Yao (Stephen) Hou wrote: > >Dear FLOW users: > >I am wondering if anyone here has experience in running the 4-color panel, >FITC PE 7AAD & APC on a dual-laser Calibur. Can we separate the signals between >7AAD and APC? I appreciate any experience or publication in this aspect. Thanks > >Stephen Hou
This archive was generated by hypermail 2b29 : Sat Mar 10 2001 - 19:31:03 EST