GNS cells were cultured in StemPro NSC medium (Thermo Fisher) as described previously.27 (link) The neuroblastoma line LAN-1 was maintained in Dubesco’s Modified Eagle Medium (DMEM)-F12 media with 10% Fetal Calf Serum, 1% Glutamax, 1% Pen/Step. Peripheral T cells were separated from blood samples and used to generate GD2-specific third-generation CAR-T cells using GD2-iCAR retroviral vector SFG.iCasp9.2A.14g2a.CD28.OX40.zeta supernatant (Center for Cell and Gene Therapy, Baylor College of Medicine, Houston, Texas, USA) and our clinical manufacturing protocol as described previously.29 (link) The second-generation GD2-CAR-IL-15 retrovector38 58 59 (link) was obtained under a material transfer agreement with Baylor College of Medicine with the kind assistance of Professor Leonid Metelitsa. Post-thawing, CAR-T-cell products were maintained in TEXMACS media (Miltenyi) with 10 ng/mL IL-7 and 5 ng/mL IL-15 for a maximum of 10 days.