Structure-activity relationship of T-cell receptors based on alanine scanning

► TCR recognize complexes between HLA and peptides derived from intracellular proteins. ► We used alanine scanning to determine amino acids for binding to the peptide/HLA. ► Five substitutions decreased the binding affinity compared with that of wildtype TCR. ► One substitution improved the binding affinity compared with wildtype TCR. ► Our results provide fundamental information for constructing mutant TCRs.