CAR-T19 cells induced CD19 downmodulation and degradation. NALM6 cells were cocultured for 2 hours at a 1:1 E:T ratio with nontransduced Jurkat cells (J-NT), J-CAR-T19, or J-STAb-T19 cells. A, Representative dot plots showing CD2, CD19, and CD10 expression. B, Analysis of 19-CAR expression. C, Representative images of CD19 and LAMP1 cellular localization in NALM6 cells cocultured with J-NT-T, J-CAR-T19, or J-STAb-T19 cells. D, Pearson coefficients' for CD19 and LAMP1 colocalization assessment in NALM6 cells in the indicated cocultures. Dots represent the analyzed cells in one experiment representative of two performed. Mean ± SD values are shown. The P values were calculated with one-way ANOVA with Tukey multiple comparison tests.