Abstract
Abstractαβ T-cell receptors (TCRs) recognize aberrant peptides bound to major histocompatibility complex molecules (pMHCs) on unhealthy cells, amplifying specificity and sensitivity through physical load placed on the TCR-pMHC bond during immunosurveillance. To understand this mechanobiology, TCRs stimulated by abundantly and sparsely arrayed epitopes (NP366-374/Dband PA224-233/Db, respectively) followingin vivoinfluenza A virus infection were studied with optical tweezers. While certain NP repertoire CD8 T lymphocytes require many ligands for activation, others are digital, needing just few. Conversely, all PA TCRs perform digitally, exhibiting pronounced bond lifetime increases through sustained, energizing volleys of structural transitioning. Optimal digital performance is superiorin vivo,correlating with ERK phosphorylation, CD3 loss, and activation marker upregulationin vitro. Given neoantigen array paucity, digital TCRs are likely critical for immunotherapies.One Sentence SummaryQuality of ligand recognition in a T-cell repertoire is revealed through application of physical load on clonal T-cell receptor (TCR)-pMHC bonds
Publisher
Cold Spring Harbor Laboratory