Simultaneous induction of Tri-antigen specific cytotoxic T lymphocytes(CTLs) using DCs transferred with WT1, survivin and TERT mRNA for adoptive T cell therapy

Abstract

T cell to tumor cell ratios, increasing anti-tumor activity and improving patient survival. We therefore incorporated the OX40 and CD28 co-stimulatory endodomains into our GD2-CAR construct in the hope they would enhance in vivo expansion and persistence of CAR T-cells in patients with relapsed/refractory neuroblastoma. Methods: This is a Phase I, dose-escalating, safety trial administering 3 generation GD2-CAR T cells to patients with relapsed/refractory neuroblastoma. Results: We have manufactured 4 autologous 3 generation GD2-CAR T cell products (patient ages: 4 e 23 years). Starting with a median of 20x10 PBMCs, we obtained a median of 450x10 CAR T cells (range 240x10 to 480x10, 18-fold expansion) after 10 3 days of culture. The transduction efficiency was 79 5% by FACS. Phenotypically, the T cell lines were 27 11% CD4 and 67 10% CD8, with 8 2% central memory (CD45ROCD62LCCR7), and 12 10% naive (CD45RACCR7) cells in the final products. Cr release assays showed the T cell lines produced 70 7% and 55 8% lysis of GD2 targets (LAN-1 and CHLA255, respectively) at a 20:1 effector:target ratio. One patient has been treated, so far without significant toxicity. Clinical and immunological results are pending. Conclusion: Generation of autolgous 3 generation CAR T cells for the treatment of high-risk neuroblastoma appears feasible and the safety and antitumor activity of the approach are now being assessed.