T cell recognition of Cys-containing HLA-A*02:01-restricted peptides and the corresponding AABA-substituted peptides. Curves indicate IFN-γ secretion by relevant T cells in response to coculture with APCs pulsed with titrated concentrations of (A) CTAG2(157–165), (B) TP53(168–176) R175H, (C) CYFIP1(116–124) I121V, (D) HIVEP2(1674–1682) P1682L, (E) PMEL(639–647), and (F) PHLPP1(563–571) G556E peptides.