Abstract
CAR-macrophage (CAR-M) therapy holds promise for the treatment of tumor and fibrotic diseases, yet genetic engineering remains the main efficacy-enhancing approach. Here we develop a non-genetic strategy using viscoelastic hydrogel to mechanically prime CAR-Ms. CAR-Ms exhibit potent phagocytosis of activated fibroblasts and collagen-degradation capacity, and hydrogel priming further enhances their cytotoxicity. Mechanistically, viscoelastic hydrogel priming reduces CAR-M membrane tension, which triggers membrane CAR to disassemble from clusters into dispersed monomers and dimers, leading to enhanced downstream signaling. In pulmonary fibrosis models, hydrogel-primed CAR-Ms demonstrate superior therapeutic outcomes, showing fibrosis reduction and microenvironment improvement. This study highlights CAR-M therapy’s potential for pulmonary fibrosis treatment and offers a distinct approach to improve CAR-M efficacy by physical stimuli.
Data availability
The main data supporting the results in this study are available within the paper and its Supplementary Information. The raw RNA-seq data are available at the Sequence Read Archive database via the accession number PRJNA1355556. Source data are provided with this paper.
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Acknowledgements
We thank Dr. Hui Zhao and Dr. Yinqiang Sui for their generous contribution of anti-CD19 CAR sequences, Nalm6 cells and their assistance in constructing the CD69 upregulation assay in this study. We appreciate Dr. Liping Deng for her guidance and suggestions in plasmid construction. We also thank Xin Wang for her help in establishing a single-molecular photobleaching assay. Some of the illustrations were created with Biorender.com. This work was supported by the National Natural Science Foundation of China-82125018 (Y.D.), National Natural Science Foundation of China-32430058 (Y.D.), and Natural Science Foundation of Beijing, China-Z230016 (Y.D.). Schematics were created using several icon elements from BioRender.com.
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Y.Z. and Y.D. conceived the study. Z.L. established the hydrogel preparation method and assisted in viscoelasticity measurements. Y.Z. performed cell engineering, phagocytosis and cytotoxicity assays, hydrogel priming of cells, and establishment and treatment of the mouse pulmonary fibrosis model. Z.L. assisted with hydrogel-related experiments. Y.A. performed tail vein injections. R.Z. contributed to pulmonary fibrosis modeling and tail vein injections. W.K. assisted with data analysis and generated 3D images of fibrotic lungs. Y.D. supervised the project. Y.Z. wrote the original draft. Y.Z. and Y.D. reviewed and edited the manuscript.
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Zhang, Y., Liu, Z., Kong, W. et al. Viscoelastic hydrogel primed CAR-macrophage for pulmonary fibrosis treatment. Nat Commun (2026). https://doi.org/10.1038/s41467-025-68033-4
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DOI: https://doi.org/10.1038/s41467-025-68033-4
