Cutting Edge: Mechanical Forces Acting on T Cells Immobilized via the TCR Complex Can Trigger TCR Signaling

sented by the MHC activates specific T cells to control infections. Recent theoretical considerations have sug-gested that mechanical forces acting on the TCR may be important for receptor triggering. In this study, we directly tested the hypothesis that physical forces act-ing on the TCR can initiate signaling in T cells by mi-cromanipulation of individual T cells bound to artificial APCs expressing engineered TCR ligands. We find that mechanical forces acting on T cells bound to APCs via the TCR complex but not other surface receptors can initiate signaling in T cells in an Src kinase-dependent fashion. Our data indicate that T cells are mechanically sensitive when coupled to APCs by the TCR and indi-cates that the TCR may act as a mechanosensor. Our data provide new insight into TCR function. Th