Expression of ILT5 on leukemia cells. (A) The titers of ILT5-specific antibodies were determined in serum samples derived from a patient who relapsed from AML. (B) B cell (top panels) and myeloid (middle panels) leukemia samples were analyzed for ILT5 expression. Blasts were identified by side scatter analysis and low CD45 expression (left panels). CD34/ILT5 expression on the gated cells is shown (right panels). (Bottom panels) Myeloma cells were identified by forward scatter/side scatter analysis (left panel) and CD138 expression (right panel).