Selectin ligands on CB-CD34⁺ cells are sialylated. Purified FucTVI-treated or control CB-CD34⁺ cells were incubated with sialidase or vehicle and assayed for P- and E-selectin binding. Sialidase treatment completely abrogated selectin binding in both FucTVI-treated and control CB-CD34⁺ cells. Shown is 1 of 3 experiments with the same result. Filled histograms represent control chimera binding performed in the presence of 5 mM EDTA.