Identification and frequency of lin⁻/HLA-DR⁺ CBDC. CB nucleated cells (A), mononuclear cells (B), SRBC⁻ cells (C), and lin⁻-enriched cells (D) were double labeled with the lineage marker (CD3, CD11b, CD14, CD16, CD19, CD34, CD56, and glycophorin A) specific MoAb and anti–HLA-DR. CBDC are indicated by rectangles and the percentages of lin⁻/HLA-DR⁺ CBDC are shown. The quadrants were set according to isotype controls.