Miniaturized scalable arrayed CRISPR screening in primary cells enables discovery at the single donor resolution
High-efficiency gene editing in primary human cells is critical for advancing therapeutic development and functional genomics,yet conventional electroporation platforms often require high cell input and are poorly suited to parallelized experiments. Here we introduce a next-generation digital microfluidics (DMF) electroporation platform that enables high-throughput,low-input genome engineering using discrete droplets manipulated on a planar electrode array. The system supports 48 independently programmable reaction sites and integrates seamlessly with laboratory automation,allowing efficient delivery of CRISPR-Cas9 RNPs and mRNA cargo into as few as 3,000 primary human cells per condition. The platform was validated across diverse primary human cell types and cargo modalities,demonstrating efficient delivery of various cargo,with high rates of transfection,gene knockout via non-homologous end joining,and precise knock-in through homology-directed repair. To showcase its utility in functional genomics,we applied the platform to an arrayed CRISPR-Cas9 screen in chronically stimulated human CD4⁺ T cells,identifying novel regulators of exhaustion,including epigenetic and transcriptional modulators. These findings establish our DMF-based electroporation platform as a powerful tool for miniaturized genome engineering in rare or precious cell populations and provide a scalable framework for high-content genetic screening in primary human cells.Supplementary InformationThe online version contains supplementary material available at 10.1038/s41598-025-13532-z.
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(Aug 2025)
Journal of Biomedical Science 32 3
CD24a knockout results in an enhanced macrophage- and CD8⁺ T cell-mediated anti-tumor immune responses in tumor microenvironment in a murine triple-negative breast cancer model
BackgroundCD24 plays a crucial role not only in promoting tumor progression and metastasis but also in modulating macrophage-mediated anti-tumor immunity. However,its impact on the immune landscape of the tumor microenvironment (TME) remains unexplored. Here,we investigated the role of CD24a,the murine CD24 gene,in tumor progression and TME immune dynamics in a murine triple-negative breast cancer (TNBC) model.MethodsClustered Regularly Interspaced Short Palindromic Repeat (CRISPR)/Cas9 knockout technology was employed to generate CD24a knockout in the murine TNBC cell line 4T1. Flow cytometry was utilized to analyze the immune cell populations,including myeloid-derived suppressor cells (MDSCs),natural killer cells,T cells,and macrophages,within tumors,spleens,and bone marrow in the orthotopic mouse 4T1 breast cancer model. Immunofluorescence (IF) staining was used to detect the immune cells in tumor sections. High-speed confocal was used to perform three-dimensional (3D) mapping of immune cells in the 4T1 orthotopic tumors.ResultsKnocking out CD24a significantly reduced tumor growth kinetics and prolonged mouse survival in vivo. Flow cytometry and IF analysis of tumor samples revealed that CD24a loss significantly promoted the infiltration of M1 macrophages and cytotoxic CD8+ T cells into the TME while reducing the recruitment and expansion of granulocytic MDSCs (gMDSCs). In vitro coculture experiments showed that CD24a deficiency significantly enhanced macrophage‐mediated phagocytosis and CD8⁺ T cell-mediated cytotoxicity,effects that were partially reversed by re‐expression of CD24a. Moreover,in vivo depletion of macrophages and CD8+ T cells reverted the delayed tumor growth caused by CD24a knockout,underscoring their critical role in tumor growth suppression associated with CD24a knockout. 3D mapping of immune cells in the TME confirmed the anti-tumor immune landscape in the CD24a knockout 4T1 tumors. Furthermore,in vitro analysis showed that CD24a loss upregulated macrophage colony-stimulating factor expression while suppressed levels of CXCL1,CXCL5,and CXCL10,chemokines known to recruit gMDSCs,further providing a molecular basis for enhanced macrophage recruitment and diminished gMDSC accumulation.ConclusionsOur findings suggest that CD24a may regulate immune suppression within the TNBC TME. Targeting CD24a enhances macrophage- and CD8⁺ T cell-mediated anti-tumor immune responses and is associated with a shift in the TME toward a more immunogenic state,thereby suppressing tumor growth. These results may support CD24 as a promising immunotherapeutic target for TNBC.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12929-025-01165-3.
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(Aug 2025)
Nature Communications 16
Integrative multi-omics reveals a regulatory and exhausted T-cell landscape in CLL and identifies galectin-9 as an immunotherapy target
T-cell exhaustion contributes to immunotherapy failure in chronic lymphocytic leukemia (CLL). Here,we analyze T cells from CLL patients’ blood,bone marrow,and lymph nodes,as well as from a CLL mouse model,using single-cell RNA sequencing,mass cytometry,and tissue imaging. T cells in CLL lymph nodes show the most distinct profiles,with accumulation of regulatory T cells and CD8+ T cells in various exhaustion states,including precursor (TPEX) and terminally exhausted (TEX) cells. Integration of T-cell receptor sequencing data and use of the predicTCR classifier suggest an enrichment of CLL-reactive T cells in lymph nodes. Interactome studies reveal potential immunotherapy targets,notably galectin-9,a TIM3 ligand. Inhibiting galectin-9 in mice reduces disease progression and TIM3+ T cells. Galectin-9 expression also correlates with worse survival in CLL and other cancers,suggesting its role in immune evasion and potential as a therapeutic target. Multi-omics can be used to characterise tumour and immune cell populations. Here the authors use multi-omics to characterise CLL blood and tissue samples and use prediction models for CLL TCR specificity and implicate interactions between galectin-9 and TIM3 as involved in CLL immune escape and propose galectin-9 as a possible immunotherapy target.
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(Aug 2025)
RMD Open 11 3
TNF inhibitors affect the induction and maintenance of spike-specific B-cell responses after mRNA vaccination
AbstractObjectivesTumour necrosis factor inhibitors (TNFi) are widely used and effective as treatment for immune-mediated inflammatory diseases (IMIDs). However,TNFi therapy causes a faster waning of antibody responses following vaccination. The underlying cause by which TNFi affect humoral immunity remains to be elucidated. The formation of long-lasting,high-affinity antibodies after vaccination results from germinal centre (GC)-derived,T cell-dependent B-cell responses. Therefore,this study investigated how TNFi affect the formation and maintenance of antigen-specific B- and CD4+ T-cell responses following SARS-CoV-2 mRNA vaccination.MethodsSARS-CoV-2 spike-specific B-cell responses were characterised using spectral flow cytometry. Spike-specific CD4+ T cells were measured using an activation-induced marker assay. 15 patients with inflammatory bowel disease (IBD) treated with TNFi were compared with 9 IBD patients without systemic immunosuppression and 10 healthy controls.ResultsSpike-specific CD4+T-cell frequency and phenotype,including T follicular helper cells,were not affected by TNFi. Total spike-specific B-cell frequencies were reduced in TNFi-treated patients. Deep phenotyping revealed lower IgG+memory B-cell frequencies in TNFi-treated patients 3–6 months after vaccination. These data were confirmed in TNFi-treated rheumatoid arthritis patients. Interestingly,already at day 7 after the second vaccination,TNFi therapy reduced the induction of class-switched CD11c- CD71+activated B cells,which are believed to be GC-derived. Conversely,CD11c+B cells,associated with extrafollicular B-cell responses,were not affected by TNFi therapy.ConclusionsThese data suggest that TNFi therapy affects the differentiation of GC-derived B cells,which may explain its effect on humoral immune responses.
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(Aug 2025)
Cancer Immunology,Immunotherapy : CII 74 9
GPX4 is a key ferroptosis regulator orchestrating T cells and CAR-T-cells sensitivity to ferroptosis
Induction of ferroptosis,an iron-dependent form of regulated cell death,holds promise as a strategy to overcome tumor resistance to conventional therapies and enhance immunotherapy responses. However,while the susceptibility of tumor cells to ferroptosis is extensively studied,limited data exists on the vulnerability of immune cells to disturbed iron balance and lipid peroxidation. Here,we found that T-cell stimulation rewires iron and redox homeostasis and by increasing levels of reactive oxygen species and labile iron promotes lipid peroxidation and T-cells’ ferroptosis. Upon stimulation,we detected changes in the balance of ferroptosis-suppressive proteins,including decrease of GPX4. Subsequently,we identified GPX4 as a master regulator orchestrating T/CAR-T-cells’ sensitivity to ferroptosis and observed that GPX4 inhibitors impair CAR-T cells’ antitumor functions. Our study demonstrated differential GPX4 expression and diverse susceptibility to ferroptosis between CD4⁺ and CD8⁺ T cells. Among analyzed subsets of naïve,central memory (CM),effector memory (EM),and terminally differentiated effector memory (TEMRA),CD8⁺ EM and CD8⁺ TEMRA cells exhibited the highest sensitivity to ferroptosis. We also showed that ferroptosis limited the anti-tumor efficacy of CAR-T cells,while ferroptosis inhibition improved their therapeutic effect,both in vitro and in vivo. Our findings are not only important to understand vulnerabilities of CAR-T cells but may also hold particular significance for their therapeutic development. In this context,future anticancer therapies should be carefully designed to selectively induce the ferroptosis of tumor cells without impeding cytotoxic cells’ antitumor efficacy. Additionally,we postulate that promoting less differentiated phenotype of CAR-T cells should be exploited therapeutically to create CAR-T products characterized by decreased sensitivity to ferroptosis within tumor microenvironment.Supplementary InformationThe online version contains supplementary material available at 10.1007/s00262-025-04133-w.
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(Jul 2025)
Journal for Immunotherapy of Cancer 13 7
Constitutive IL-7 signaling promotes CAR-NK cell survival in the solid tumor microenvironment but impairs tumor control
AbstractBackgroundAdoptive transfer of chimeric antigen receptor (CAR)-expressing natural killer (NK) cells has demonstrated success against hematological malignancies. Efficacy against solid tumors has been limited by poor NK cell survival and function in the suppressive tumor microenvironment (TME). To enhance efficacy against solid tumors,stimulatory cytokines have been incorporated into CAR-NK cell therapeutic approaches. However,current cytokine strategies have limitations,including systemic toxicities,exogenous dependencies,and unwanted TME bystander effects. Here,we aimed to overcome these limitations by modifying CAR-NK cells to express a constitutively active interleukin (IL)-7 receptor,termed C7R,capable of providing intrinsic CAR-NK cell activation that does not rely on or produce exogenous signals nor activate bystander cells.MethodsWe examined persistence,antitumor function,and transcriptional profiles of CAR-NK cells coexpressing C7R in a novel tumor immune microenvironment (TiME) co-culture system and against hematologic and solid tumor xenografts in vivo.ResultsPeripheral blood NK cells expressing a CAR directed against the solid tumor antigen GD2 and modified with C7R demonstrated enhanced tumor killing and persistence in vitro compared with CAR-NK cells without cytokine support and similar functions to CAR-NK cells supplemented with recombinant IL-15. C7R.CAR-NK cells exhibited enhanced survival and proliferation within neuroblastoma TiME xenografts in vivo but produced poor long-term tumor control compared with CAR-NK cells supplemented with IL-15. Similar results were seen using C7R-expressing CD19.CAR-NK cells against CD19+leukemia xenografts. Gene expression analysis revealed that chronic signaling via C7R induced a transcriptional signature consistent with intratumor stressed NK cells with blunted effector function. We identified gene candidates associated with chronic cytokine-stressed NK cells that could be targeted to reduce CAR-NK cell stress within the solid TME.ConclusionC7R promoted CAR-NK cell survival in hostile TMEs independent of exogenous signals but resulted in poor antitumor function in vivo. Our data reveals the detrimental role of continuous IL-7 signaling in CAR-NK cells and provides insights into proper application of cytokine signals when attempting to enhance CAR-NK cell antitumor activity.
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