CD28 and neoplasm: As shown in Fig. 2a, CAR.CD19.CD28-T cells were co-cultured with Daudi tumor cells at suboptimal conditions of decreased E:T ratio (from 1:1 to 1:2.5), showing that, also in this case, the antitumor activity of CAR.CD19-T cells exposed to emapalumab at the highest dose of 100 μg/ml was superimposable to that of CAR-T cells in the absence of the drug.