Great teamwork: P Datlinger*✉️, E Pankevich*, C Arnold*, N Pranckevicius, J Lin, D Romanovskaia, M Schäfer, F Piras, AC Orts, A Nemc, P Biesaga, M Chan, T Neuwirth, A Artemov, W Li, S Ladstätter, T Krausgruber & C Bock✉️ (*first authors, ✉️correspondance).

CELLFIE supports diverse CRISPR modalities. Base editing proved especially powerful. Tiling screens of RHOG suggest inhibition of GTP binding pocket as therapeutic angle and identified gRNAs for clinical translation. (7/7)

With many promising single edits reported across labs, the key challenge is combining them into tailored therapeutic designs. We extended CELLFIE with combinatorial screens and discovered a strong synergy between RHOG and FAS knockouts. (6/7)

We developed in vivo CROP-seq for screens in mouse immunotherapy models. By reading gRNAs from abundant mRNA and tracking individual clones, we identified RHOG, FAS, and PRDM1 as CAR T boosters. In vivo CROP-seq supports discovery screens with thousands of perturbations. (4/7)

To address clinical limitations of CAR T therapies, we performed genome-scale FACS screens for target recognition, T cell activation, apoptosis/fratricide, and exhaustion—resulting in the largest CAR T screening dataset to date. (3/7)

We ran genome-wide screens for T cell fitness under TCR and repeated target cell stimulation. This revealed novel knockouts that enhance CAR T cell persistence, alongside many well-known clinical targets. (2/7)

#CELLFIE for CAR T screening—a new mRNA-based platform for screening primary cells. CAR + gRNA library are delivered by lentivirus, CRISPR modifiers as electroporated mRNA. That’s more flexible and effective than existing T cell screening methods. (1/7)