case_images: PMC11099209_01
case_images: Final CAR-T cell product and CAR-T cell subsets persistence characteristics. (A) CD4+ and CD8+ subsets composition of the final CAR-T cell product; (B) Persistence of CD4+ and CD8+ CAR-T cells; (C) Cmax, AUC0-28 days and AUC0-3 months; (D, E) Flow cytometry plots of CAR-T cells in the peripheral blood and cerebrospinal fluid.
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case_images: Following ex vivo lentiviral transduction and expansion, CAR-T cells totaling approximately 1.29 * 106 cells were obtained, with CD4+ CAR-T cells constituting 85.3% ( Figure 1A ). Serum concentrations of inflammatory markers also significantly increased, and CAR-T cells reached Cmax at 56.3% (77.7 cells/muL) on day +14 ( Figures 1C ,  2 ). In our case, CAR-T cell expansion was primarily achieved through CD4+ CAR-T cells, resulting in a CD4+/CD8+ ratio of 89 ( Figures 1B ,  2 ). CAR-T cells comprised 31.6% of leukocytes in the cerebrospinal fluid, with a CD4+/CD8+ CAR-T cell ratio of 54 ( Figures 1D, E ). CAR-T cells continued to be detected at significant levels in the peripheral blood (+28 days - 27.9 cells/mul, +3 months - 2.5 cells/mul, +6 months - 0.76 cells/mul), maintaining B-cells aplasia ( Figures 1D, E ,  2 ). The AUC for 0-3 months amounted to 1333 cells/mul, including CD4+ CAR-T cells 1269.4 cells/mul ( Figure 1C ).
case_images: Biochemical and immunological kinetics after CD19 CAR-T cell infusion.
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case_images: After 7 days of CAR-T cell infusion, the patient's symptoms improved, dyspnea resolved, inflammatory markers returned to normal values, and no signs of CRS or ICANS were registered in the first 10 days (see  Figure 2 ). Serum concentrations of inflammatory markers also significantly increased, and CAR-T cells reached Cmax at 56.3% (77.7 cells/muL) on day +14 ( Figures 1C ,  2 ). In our case, CAR-T cell expansion was primarily achieved through CD4+ CAR-T cells, resulting in a CD4+/CD8+ ratio of 89 ( Figures 1B ,  2 ). IT chemotherapy, the patient showed a dramatic clinical improvement, with ICANS decreasing to grade II (ICE 6 points). In less than 32 hours after the IT chemotherapy, the patient's ICANS had resolved to grade 0, inflammatory markers decreased, and steroid therapy was discontinued to ensure CAR-T cell function ( Figure 2 ). CAR-T cells continued to be detected at significant levels in the peripheral blood (+28 days - 27.9 cells/mul, +3 months - 2.5 cells/mul, +6 months - 0.76 cells/mul), maintaining B-cells aplasia ( Figures 1D, E ,  2 ).
case_images: Radiological scans during CD19 CAR-T cell therapy.
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case_images: PET/CT scans at +3 months ( Figure 3 ) and CT scans at +6 and +9 months confirmed an ongoing complete remission (CR).