Antimyeloma efficacy of SLAMF7-CAR T cells in vivo. NSG mice were inoculated with CD38⁺CD138⁺SLAMF7⁺ ffluc_eGFP–transduced MM.1S myeloma cells (IV) and, 14 days later, treated with a single dose of SLAMF7-CAR T cells or CD19-CAR (control) T cells (both: IV, 2.5 × 10⁶ CD4⁺ and 2.5 × 10⁶ CD8⁺; total dose: 5 × 10⁶) or remained untreated (n = 5 mice per group). (A) Serial bioluminescence imaging to assess myeloma progression/regression. Radiance was measured in regions of interest that encompassed the entire body of mice. Labels on the left state the day after inoculation with MM.1S myeloma cells. (B) Flow cytometric analysis of peripheral blood (PB), bone marrow (BM), and spleens (SP) to detect residual MM.1S myeloma cells in exemplary mice that were euthanized in each treatment group on day 35 after tumor inoculation (ie, day 21 after treatment). (C) Waterfall plot shows the relative increase/decrease in bioluminescence signal between day 14 (before treatment) and day 20 (6 days after treatment) in individual mice. (A-C) The data shown are representative of 3 independent experiments with SLAMF7-CAR and control CD19-CAR T cells prepared from 3 healthy donors.