Tumor control via targeting PD-L1 with chimeric antigen receptor modified NK cells
Yvette Robbins, Sarah Greene, Jay Friedman, Paúl E. Clavijo, Carter Van Waes, Kellsye P. Fabian, Michelle R. Padget, Houssein Abdul Sater, John H Lee, Patrick Soon‐Shiong, James L. Gulley, Jeffrey Schlom, James W. Hodge, Clint Allen
Abstract
Failed T cell-based immunotherapies in the presence of genomic alterations in antigen presentations pathways may be overcome by NK cell-based immunotherapy. This approach may still be limited by the presence of immunosuppressive myeloid populations. Here, we demonstrate that NK cells (haNKs) engineered to express a PD-L1 chimeric antigen receptor (CAR) haNKs killed a panel of human and murine head and neck cancer cells at low effector-to-target ratios in a PD-L1-dependent fashion. Treatment of syngeneic tumors resulted in CD8 and PD-L1-dependent tumor rejection or growth inhibition and a reduction in myeloid cells endogenously expressing high levels of PD-L1. Treatment of xenograft tumors resulted in PD-L1-dependent tumor growth inhibition. PD-L1 CAR haNKs reduced levels of macrophages and other myeloid cells endogenously expressing high PD-L1 in peripheral blood from patients with head and neck cancer. The clinical study of PD-L1 CAR haNKs is warranted.