Purification strategy for isolating cells stained with CD34/CD71 and HLA-DR. Live cells were gated on the basis of PI staining (A), and these cells were then gated on the basis of low side scatter (B). Subsequently, cells were gated for expression of CD34-Cy5, into CD34⁺ (R3) or CD34⁻ (R4) windows (C). The CD34⁺ cells in R3 were then sorted on the basis of their expression of CD71-PE and HLA-DR-FITC (D). Sort gates for C and D were set up to exclude 100% of the cells in an isotype control.