Dendritic cell Piezo1 integrating mechanical stiffness and inflammatory signals directs the differentiation of T _H 1 and T _reg cells in cancer

Dendritic cells (DCs) play an important role in anti-tumor immunity by inducing T cell differentiation. Herein, we found that the mechanical sensor Piezo1 expressed by DCs integrates innate inflammatory stimuli and stiffness signals and directs the reciprocal differentiation of T _H 1 and regulatory T (T _reg ) cells in cancer. Genetic deletion of Piezo1 in DCs inhibited the generation of T _H 1 cells while driving the development of T _reg cells in promoting cancer growth. Mechanistically, Piezo1-deficient DCs regulated the secretion of the polarizing cytokines TGFβ1 and IL-12, leading to increased TGFβR2-p-Smad3 activity and decreased IL-12Rβ2-p-STAT4 activity while inducing the reciprocal differentiation of T _reg and T _H 1 cells. In addition, Piezo1 integrated the SIRT1-hypoxia-inducible factor-1 alpha (HIF1α)-dependent metabolic pathway and calcium-calcineurin-NFAT signaling pathway to orchestrate reciprocal T _H 1 and T _reg lineage commitment through DC-derived IL-12 and TGFβ1. Our studies provide critical insight for understanding the role of the DC-based mechanical regulation of immunopathology in directing T cell lineage commitment in tumor microenvironments.