Transient overexpression of IKZF1 enhances memory precursor phenotype in CAR-T cells 4151

Abstract Description Chimeric antigen receptor (CAR)-T cell therapy represents a groundbreaking advancement in cancer treatment, with its success hinging on the long-term persistence of CAR-T cells. This persistence relies on the formation of long-lived memory CAR-T cells that provide durable protection against cancer recurrence. However, the mechanisms regulating CAR-T cell longevity remain only partially understood. Our previous research highlighted asymmetric cell division (ACD) as a pivotal process in determining cell fate following CAR-T activation, revealing distinct roles for proximal and distal daughter cells. Building on these findings, we investigated candidates of memory commitment by modulating fate-determining transcription factors (TFs) during ACD in CAR-T cells. Using CRISPR/Cas9 gene editing, we identified IKZF1 as necessary for the memory formation of distal daughter cells during ACD, as its loss impaired memory precursor development. We then demonstrated that transient overexpression of IKZF1 via mRNA-lipid nanoparticles (LNP) during ACD is sufficient to enhance the memory precursor phenotype of CAR-T cells, without compromising in vitro cytotoxicity. Furthermore, IKZF1 overexpression induced a metabolic phenotype reminiscent of resting CAR-T cells. These findings underscore the potential of transient IKZF1 overexpression as a novel strategy to modulate CAR-T cell fate and enhance memory formation, providing a promising avenue to improve the durability of CAR-T therapies. Funding Sources NIH 5K08AR080266-04 Topic Categories Tumor Immunology: Checkpoints, Prevention, and Treatment (TIPT)