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E. Klotzsch, G. Schütz:
"Improved Ligand Discrimination by Force-Induced Unbinding of the T Cell Receptor from Peptide-MHC";
Biophysical Journal, 104 (2013), 1670 - 1675.

T cell activation is mediated via the recognition of peptides by the T cell receptor (TCR). This receptor ligand interaction
is highly specific, and the TCR has to discriminate between a huge number of peptides presented by the products of the
major histocompatibility complexes (MHCs). Recent studies indicate that cells probe the TCR-pMHC interaction by imposing
force on the interaction. Here we investigated in a theoretical analysis the consequences of such force-induced unbinding for
T cell recognition. Our findings are as follows. First, the bond rupture under force is much faster, improving the time resolution
of the discrimination process. Second, cells can access additional parameters characterizing the shape of the binding energy
surface. Third, load-induced unbinding yields a reduced coefficient of variation of the bond lifetimes, which improves the discriminative
power even between peptide/MHCs (pMHCs) with similar off-rates.