Lei, KewenKurum, ArmandKaynak, MuratBonati, LuciaHan, YulongCencen, VeronikaGao, MinXie, Yu-QingGuo, YugangHannebelle, Melanie T. M.Wu, YangpingZhou, GuanyuGuo, MingFantner, Georg E.Sakar, Mahmut SelmanTang, Li2021-12-182021-12-182021-12-182021-12-0610.1038/s41551-021-00826-6https://infoscience.epfl.ch/handle/20.500.14299/183920WOS:000727131700001Cancer cells enriched in cholesterol in their plasma membrane impair T-cell-mediated cytotoxicity, which can be augmented by stiffening the cancer cells via cholesterol depletion, as shown in mouse models of adoptive T-cell immunotherapy. Malignant transformation and tumour progression are associated with cancer-cell softening. Yet how the biomechanics of cancer cells affects T-cell-mediated cytotoxicity and thus the outcomes of adoptive T-cell immunotherapies is unknown. Here we show that T-cell-mediated cancer-cell killing is hampered for cortically soft cancer cells, which have plasma membranes enriched in cholesterol, and that cancer-cell stiffening via cholesterol depletion augments T-cell cytotoxicity and enhances the efficacy of adoptive T-cell therapy against solid tumours in mice. We also show that the enhanced cytotoxicity against stiffened cancer cells is mediated by augmented T-cell forces arising from an increased accumulation of filamentous actin at the immunological synapse, and that cancer-cell stiffening has negligible influence on: T-cell-receptor signalling, production of cytolytic proteins such as granzyme B, secretion of interferon gamma and tumour necrosis factor alpha, and Fas-receptor-Fas-ligand interactions. Our findings reveal a mechanical immune checkpoint that could be targeted therapeutically to improve the effectiveness of cancer immunotherapies.Engineering, BiomedicalEngineeringplasma-membraneforce microscopystiffnesscyclodextrinsplasticitymechanicsdynamicsactintcrtext::journal::journal article::research article