Tumor-Targeted Human T Cells Expressing CD28-Based Chimeric Antigen Receptors Circumvent CTLA-4 Inhibition
Fig 1
Different CD28 costimulation for CD3z/CD28-based CAR or CD3z-based CAR + CD80 transduced T cells.
(A) Plots represent CAR transduction efficiencies in primary T cells, measured by flow cytometry 4 days after retroviral transduction. Numbers in upper left quadrants indicate percentages of transduced cells; numbers in lower right quadrants indicate CAR MFIs. Since ΔLNGFR is used as a technical control and has no functional impact on T cells, it is omitted in the termed T-cell groups for clarity. (B) In vitro T cell growth of 19z1+, 19z1-CD80+ and 19-28z+ T cells weekly cocultured with artificial antigen presenting cells (aAPC) expressing CD19 or CD19 and CD80, as indicated, without exogenous cytokines. CAR expression was weekly determined by flow cytometry. Arrows indicate stimulation time points. (C, D) Cytokine concentrations measured in supernatants of cocultures depicted in B, at day 8 (C) and day 22 (D). These data are representative of one out of three different experiments producing similar patterns.