Checkpoint Blockade Reverses Anergy in IL-13Rα2 Humanized scFv-Based CAR T Cells to Treat Murine and Canine Gliomas

作者：Yibo Yin, Alina C. Boesteanu, Zev A. Binder, Chong Xu, Reiss Reid, Jesse L. Rodriguez, Danielle Cook, Radhika Thokala, Kristin Blouch, Bevin McGettigan-Croce, Logan Zhang, Christoph Konradt, Alexandria P. Cogdill, M. Kazim Panjwani, Shuguang Jiang, Denis Migliorini, Nadia Dahmane, Avery D. Posey, Carl H. June, Nicola J. Mason, Zhiguo Lin, Donald M. O’Rourke, Laura A. Johnson · 发表于：Molecular Therapy — Oncolytics · 年份：2018 · DOI：10.1016/j.omto.2018.08.002 · 被引用次数：179 · 研究领域：CAR-T cell therapy research、Virus-based gene therapy research、Immunotherapy and Immune Responses

We generated two humanized interleukin-13 receptor α2 (IL-13Rα2) chimeric antigen receptors (CARs), Hu07BBz and Hu08BBz, that recognized human IL-13Rα2, but not IL-13Rα1. Hu08BBz also recognized canine IL-13Rα2. Both of these CAR T cell constructs demonstrated superior tumor inhibitory effects in a subcutaneous xenograft model of human glioma compared with a humanized EGFRvIII CAR T construct used in a recent phase 1 clinical trial (ClinicalTrials.gov: NCT02209376). The Hu08BBz demonstrated a 75% reduction in orthotopic tumor growth using low-dose CAR T cell infusion. Using combination therapy with immune checkpoint blockade, humanized IL-13Rα2 CAR T cells performed significantly better when combined with CTLA-4 blockade, and humanized EGFRvIII CAR T cells' efficacy was improved by PD-1 and TIM-3 blockade in the same mouse model, which was correlated with the levels of checkpoint molecule expression in co-cultures with the same tumor in vitro . Humanized IL-13Rα2 CAR T cells also demonstrated benefit from a self-secreted anti-CTLA-4 minibody in the same mouse model. In addition to a canine glioma cell line (J3T), canine osteosarcoma lung cancer and leukemia cell lines also express IL-13Rα2 and were recognized by Hu08BBz. Canine IL-13Rα2 CAR T cell was also generated and tested in vitro by co-culture with canine tumor cells and in vivo in an orthotopic model of canine glioma. Based on these results, we are designing a pre-clinical trial to evaluate the safety of canine IL-13Rα...