Language
English
Publication Date
4-2-2025
Journal
Cancer Immunology Research
DOI
10.1158/2326-6066.CIR-24-0259
PMID
39820712
PMCID
PMC11962401
PubMedCentral® Posted Date
1-16-2025
PubMedCentral® Full Text Version
Author MSS
Abstract
Natural killer T cells (NKTs) are a promising platform for cancer immunotherapy, but few genes involved in the regulation of NKT therapeutic activity have been identified. To find regulators of NKT functional fitness, we developed a CRISPR/Cas9-based mutagenesis screen that uses a guide RNA (gRNA) library targeting 1,118 immune-related genes. Unmodified NKTs and NKTs expressing a GD2-specific chimeric antigen receptor (GD2.CAR) were transduced with the gRNA library and exposed to CD1d+ leukemia or CD1d-GD2+ neuroblastoma cells, respectively, over six challenge cycles in vitro. Quantification of gRNA abundance revealed enrichment of PRDM1-specific gRNAs in both NKTs and GD2.CAR NKTs, a result that was validated through targeted PRDM1 knockout. Transcriptional, phenotypic, and functional analyses demonstrated that CAR NKTs with PRDM1 knockout underwent central memory-like differentiation and resisted exhaustion. However, these cells downregulated the cytotoxic mediator granzyme B and showed reduced in vitro cytotoxicity and only moderate in vivo antitumor activity in a xenogeneic neuroblastoma model. In contrast, short hairpin RNA-mediated PRDM1 knockdown preserved effector function while promoting central memory differentiation, resulting in GD2.CAR NKTs with potent in vivo antitumor activity. Thus, we have identified PRDM1 as a regulator of NKT memory differentiation and effector function that can be exploited to improve the efficacy of NKT-based cancer immunotherapies.
Keywords
Positive Regulatory Domain I-Binding Factor 1, Animals, Humans, Natural Killer T-Cells, Mice, Immunologic Memory, Cell Line, Tumor, Immunotherapy, Adoptive, CRISPR-Cas Systems, Xenograft Model Antitumor Assays, Receptors, Chimeric Antigen, Neuroblastoma
Published Open-Access
yes
Recommended Citation
Tian, Gengwen; Barragan, Gabriel A; Yu, Hangjin; et al., "PRDM1 Is a Key Regulator of the NKT-cell Central Memory Program and Effector Function" (2025). Faculty, Staff and Students Publications. 6331.
https://digitalcommons.library.tmc.edu/baylor_docs/6331