CAR T cells with mAb therapy provides an additive antitumor effect. (A) NSG mice that underwent engraftment IP with Raji-GFP/Luc tumor cells were treated with 5e5 CD19-CAR T cells and 4 total doses of rituximab (100 μg/mouse) on the indicated days. (B) Tumor burden was assessed via BLI and shown for a representative study, and (C) total luminescence was quantified and normalized to pretreatment tumor burden. (D) Survival curves for tumor-bearing mice (2 independent experiments) treated with CD19-targeted CAR T cells and rituximab or a control mAb. (E) NSG mice received engraftment IP with Raji tumors, and all mice received a round of 4 doses (100 μg/mouse) of rituximab. Mice were subsequently divided into the indicated treatment groups. CAR-treated mice were given a dose of 5e5 CAR T cells. (F) Tumor burden was monitored via BLI. See supplemental Figure 2B for the associated survival curve. (G) Overall survival (OS) curves for mice pretreated with rituximab followed by a 10 day rest period. Rituximab-refractory experiment is shown for 1 representative study. See supplemental Figure 2 for replicates. Statistics were performed using a log-rank survival analysis.