Tumor cells in primary culture are specifically killed by BiAb-armed ATC. Ex vivo glioma cells expressing both HER2/neu and EGFR were incubated overnight with unarmed ATC or ATC armed with HER2Bi, EGFRBi or CD20Bi. The data are pooled from 4 experiments, using 4 different ATC donors and a range of E:T. Residual viabilities (mean ± SEM) based upon MTT assays are shown. The targets are killed by HER2Bi- and EGFRBi-armed ATC, whereas unarmed and CD20Bi-armed ATC fail to kill. Mean of 4 donors (± SEM), when compared with unarmed ATC, the residual viable cells after HER2Bi- or EGFRBi-ATC were statistically significant (p < 0.001, 1-way ANOVA; ***). Arming with CD20BiAb showed no statistically significant difference from unarmed ATC (p > 0.05, 1-way ANOVA; n.s.). Lower panel: Shows the HER2 (7.15%) and EGFR (9.99%) expression as percent positive cells in this ex vivo cell line.