Characterization of the drug products. CD19-CAR–Retro_ALLO and CD19-CAR–Lenti_ALLO were characterized via flow cytometry in terms of levels of transduction (A), CD4⁺ and CD8⁺ subpopulations (B); memory phenotype, with identification of naive (N), CM, EM, and terminally differentiated effector memory cells reexpressing CD45ra (TEMRA) (C-D); and activation (A)/exhaustion (E) profile.