Dose dependent enhancement of anti-tumor cytotoxicity of expanded ATC by ipilimumab. Effect of ipilimumab on BiAb-mediated T cell cytotoxicity was examined by adding ipilimumab at the initiation of ATC expansion cultures from healthy donors at various concentrations ranging from 0 to 50 μg/mL. ATC were harvested on day 14, armed with EGFRBi or CD20Bi, and co-cultured at 25:1 E:T ratio for 18 hours with COLO356/FG ( left) or 4 hours with Daudi ( right ) for cytotoxicity assay. BiAb-mediated tumor specific cytotoxicity was measured by 51Cr release assay. Each bar represents a mean ± SE of 3 donors (COLO356/FG) or 4 donors (Daudi). The dose-dependent effect of ipilimumab was statistically significant in matched sample, one-way ANOVA for COLO356/FG (*p < 0.05) and Daudi (**p < 0.05).