Phenotypic analysis of CD4⁺ CD34⁺⁺ Lin⁻ LDFL cells. CD34⁺⁺ Lin⁻ LDFL cells were isolated by immunomagnetic bead depletion of GPA⁻ LDFL cells after staining with FITC-labeled MoAb against CD3, CD8, CD10, CD14, CD15, CD16, CD19, and CD20. These Lin⁻ cells were then stained for CD34 expression in a two-step protocol using anti-CD34-biotin followed by streptavidin-APC or streptavidin-TC. CD34⁺⁺ Lin⁻ PI⁻ LDFL cells were isolated by FACS. The sorted cells were stained for CD4 and the other cell-surface markers indicated. Additionally, staining with CD4 and Rh123 was also performed, for which the incubation periods for Rh123 efflux are indicated. These data are shown using linear-density contour plots with one degree of smoothing. A 10% resolution was used for all plots except for the analyses of cytokine receptor expression and HLA-DR, which are shown at 5% resolution. However, the analysis of CD38 versus CD4 expression is shown on a 50% logarithmic-density contour plot to show the expression of CD4 on the rare subpopulation of CD34⁺⁺ that does not express CD38. These data are compiled from the analyses of multiple tissues and are representative of at least two analyses per phenotype.