CRISPR-screen informed engineered T cell therapies

Adoptive T cell therapies can deliver curative responses for refractory patients with B cell malignancies, yet clinical activity in solid tumors remains inconsistent. Tumor-intrinsic barriers dominating this inconsistency include the immunosuppressive solid tumor microenvironment (TME) imposing chronic inhibitory cues to T cells and the scarcity of patient-shared and uniformly expressed tumor-restricted antigens for T cells to target. CRISPR-based forward genetics screens enable mapping of the functional genome regulating T cell anti-tumor activity. Here, we review recent insights from pooled CRISPR knockout screens in T cells to define convergent targets and pathways regulating T cell anti-tumor function and align the pharmacology of engineered T cells with sequential barriers they encounter within the TME. We additionally propose a framework for CRISPR screen-enabled target prioritization and present an example of how these principles can be applied to the functional enhancement of T cells through TIL (Tumor Infiltrating Lymphocyte) therapy, which utilizes a patient’s personalized immune response against solid tumor antigens.