Obajdin, Larcombe-Young, Davies, and Maher et al. showed in xenograft models that CAR T cells engineered to express NKG2D and an adaptor protein comprising the ITAM-expressing Dap12 endodomain fused to the C terminus of Dap10 (which naturally associates with NKG2D) persisted and rejected a wide range of NKG2DL+ solid tumors, even upon tumor rechallenge. The CAR T cells’ potency relied on high NKG2D cell surface expression, Dap10 rather than CD28 costimulation, Dap10 provision as an adaptor (vs. fused linearly), plasma cell membrane proximity of the Dap10-Dap12 adaptor, and the number of Dap12 ITAMs per CAR monomer.
Contributed by Paula Hochman
ABSTRACT: NKG2D ligands (NKG2DLs) are broadly expressed in cancer. To target these, we describe an adaptor chimeric antigen receptor (CAR) termed NKG2D/Dap10-12. Herein, T cells are engineered to co-express NKG2D with a fusion protein that comprises Dap10 joined to a Dap12 endodomain. NKG2D/Dap10-12 T cells elicit compelling efficacy, eradicating or controlling NKG2DL-expressing tumors in several established xenograft models. Importantly, durable responses, long-term survival, and rejection of tumor re-challenge are reproducibly achieved. Efficacy is markedly superior to a clinical stage CAR analog, comprising an NKG2D-CD3_ fusion. Structure-function analysis using an extended CAR panel demonstrates that potency is dependent on membrane proximity of signaling units, high NKG2D cell surface expression, adaptor structure, provision of exogenous Dap10, and inclusion of one rather than three immune tyrosine activation motifs per signaling unit. Potent therapeutic impact of NKG2D/Dap10-12 T cells is also underpinned by enhanced oxidative phosphorylation, reduced senescence, and transcriptomic re-programming for increased ribosomal biogenesis.
Author Info: (1) King's College London, School of Cancer and Pharmaceutical Sciences, CAR Mechanics Lab, London SE1 9RT, UK. (2) King's College London, School of Cancer and Pharmaceutical Scien
Author Info: (1) King's College London, School of Cancer and Pharmaceutical Sciences, CAR Mechanics Lab, London SE1 9RT, UK. (2) King's College London, School of Cancer and Pharmaceutical Sciences, CAR Mechanics Lab, London SE1 9RT, UK. (3) Leucid Bio Ltd, Guy's Hospital, London SE1 9RT, UK. (4) Leucid Bio Ltd, Guy's Hospital, London SE1 9RT, UK. (5) Leucid Bio Ltd, Guy's Hospital, London SE1 9RT, UK. (6) King's College London, Department of Infectious Diseases, School of Immunology and Microbial Sciences, Guy's Hospital, London SE1 9RT, UK. (7) King's College London, School of Cancer and Pharmaceutical Sciences, CAR Mechanics Lab, London SE1 9RT, UK. (8) Department of Respiratory Medicine, Division of Medicinal Sciences, University College London, London, UK. (9) Leucid Bio Ltd, Guy's Hospital, London SE1 9RT, UK. (10) Leucid Bio Ltd, Guy's Hospital, London SE1 9RT, UK. (11) Leucid Bio Ltd, Guy's Hospital, London SE1 9RT, UK. (12) Leucid Bio Ltd, Guy's Hospital, London SE1 9RT, UK. (13) Department of Thoracic Surgery, Guy's and St. Thomas' NHS Trust Foundation, London SE1 9RT, UK. (14) Department of Physics, King's College London, London WC2R 2LS, UK. (15) Division of Digestive Diseases, Faculty of Medicine, Imperial College London, London W12 0NN, UK. (16) King's College London, Centre for Stem Cells and Regenerative Medicine & Institute for Liver Studies, Guy's Hospital, London SE1 9RT, UK. (17) King's College London, Department of Infectious Diseases, School of Immunology and Microbial Sciences, Guy's Hospital, London SE1 9RT, UK. (18) Leucid Bio Ltd, Guy's Hospital, London SE1 9RT, UK. (19) King's College London, School of Cancer and Pharmaceutical Sciences, CAR Mechanics Lab, London SE1 9RT, UK; Leucid Bio Ltd, Guy's Hospital, London SE1 9RT, UK; Department of Immunology, Eastbourne Hospital, Kings Drive, Eastbourne, East Sussex BN21 2UD, UK. Electronic address: john.maher@kcl.ac.uk.
