Structure-activity mapping of the peptide- and force-dependent landscape of T-cell activation
Abstract Adaptive immunity relies on T lymphocytes that use αβ T-cell receptors (TCRs) to discriminate amongst peptides presented by MHC molecules (pMHCs). An enhanced ability to screen for pMHCs capable of inducing robust T-cell responses could have broad applications in diagnosing and treating immune diseases. T-cell activation in vivo relies on biomechanical forces to trigger activation by sparse antigenic pMHCs. However, in vitro screening tests potential pMHCs without force and at high (non-physiological) pMHC densities and thus often fails to predict potent agonists in vivo. Here, we present a technology that uses biomechanical force to initiate T-cell triggering in high throughput. BATTLES (Biomechanically-Assisted T-cell Triggering for Large-scale Exogenous-pMHC Screening) displays candidate pMHCs on spectrally encoded ‘smart beads’ capable of applying physiological loads to T cells, facilitating exploration of the force- and sequence-dependent landscape of T-cell responses. BATTLES can be used to explore basic T-cell mechanobiology and T cell-based immunotherapies.