Recognition of cyclic peptides by T cells. The T cell clone 430.1.142 (specific for the DQ2-αI gliadin epitope) was stimulated by cyclic peptides harboring the DQ2-αI sequence. (■) P198, (▲) peptide 1, (▼) peptide 2, (◆) peptide 3, (●) peptide 4, (□) peptide 5, (△) peptide 6, (▽) peptide 7, (◇) LQPFPQPELPY. The inset shows CPM in lower ranges for non stimulatory cyclic peptides. P198: KPLLIIAEDVEGEY; Mycobacterium bovis 65 kDa heat shock protein 243-255Y. Mean and SD is shown.