Multi-phenotype CRISPR-Cas9 Screen Identifies p38 Kinase as a Target for Adoptive Immunotherapies

Abstract

T cells are central to all currently effective cancer immunotherapies, but the characteristics defining therapeutically effective anti-tumor T cells have not been comprehensively elucidated. Here, we delineate four phenotypic qualities of effective anti-tumor T cells: cell expansion, differentiation, oxidative stress, and genomic stress. Using a CRISPR-Cas9-based genetic screen of primary T cells we measured the multi-phenotypic impact of disrupting 25 T cell receptor-driven kinases. We identified p38 kinase as a central regulator of all four phenotypes and uncovered transcriptional and antioxidant pathways regulated by p38 in T cells. Pharmacological inhibition of p38 improved the efficacy of mouse anti-tumor T cells and enhanced the functionalities of human tumor-reactive and gene-engineered T cells, paving the way for clinically relevant interventions.

Keywords: CD19 CAR T cell; CRISPR-Cas9 screen; DNA damage; NY-ESO-1; ROS; adoptive transfer immunotherapy; differentiation; multi-phenotype; neoantigen TIL; p38.