Phenotypic analysis of in vitro-generated CD1a⁺ cells. Purified CD34⁺ CB cells were cultured for 10 days in serum-free medium in the presence of FL plus TGF-β1, GM-CSF, TNFα, and SCF. They were then harvested and combined-stained for expression of CD1a and several informative molecules as indicated. Overlay diagrams show expression of the indicated molecules (lines) versus negative control (dotted lines) by gated CD1a⁺ cells. CD1a⁺ cells were gated in separate diagrams (CD1a v SSC, not shown). Histograms represent at least 3,000 gated CD1a⁺ cells.