AMG 330-induced cytotoxicity in primary human AML cells. (A-C) Pretreatment specimens from 3 adult patients with normal karyotype AML were phenotypically assessed to enumerate endogenous T cells and quantify CD33 expression on myeloid blasts. Parallel aliquots of cells were incubated with increasing concentrations of AMG 330 and various E:T cell ratios using healthy donor T cells. After 48 hours, cell counts were determined and cytotoxicity was assessed with DAPI staining to quantify drug-specific cytotoxicity. Individual results for samples #1, #2, and #3 are depicted in panels A, B, and C, respectively. Mean values are shown from 1 experiment performed in duplicate wells using a single healthy donor as source for exogenous T cells.