Figure 4.

Enhanced antigen presentation of peptide 3 relative to peptide 1. (A) Peptides 1 (□) and 3 (■) (10 μM) were incubated with γ-irradiated VAVY cells for either 2 hours or overnight before being removed. Polyclonal T cell line P28 TCL1 proliferation was used to assess the amount of peptide-DQ2 complexes on the surface of the VAVY cells. (B) Titration of peptides 1, 3, 12, and 13 using P28 TCL3 T cells. Although aldehyde peptide 3 showed enhanced antigen presentation relative to non-aldehyde peptide 1, di-aldehyde peptide 13 showed a decreased level of antigen presentation compared to its parent peptide 12. Peptide 1 ■ (EC₅₀ = 3.3 μM); Peptide 3 □ (EC₅₀ = 1.0 μM); Peptide 12 ▲ (EC₅₀ = 0.016 μM); Peptide 13 △ (EC₅₀ = 0.039 μM)