Fig. 4.

Human monocyte-derived DCs generate primarily light NS1_122–130 peptide after culture with UV irradiated, IAV A/X-31 infected, SILAC-labeled, A2⁻ BEAS cells. (A) Poisson detection chromatogram for light NS1_122–130 identifies elution at scan 1,088. (B) MS at scan 1,088. The heavy form at m/z 518.8 is about 5% of the light form at m/z 515.8. (C) SILAC labeling of an A2⁺ LAZ cell line produces dominantly heavy-labeled peptides as shown by the low energy (C) precursor spectrum and high energy (D) fragment spectrum of the gamma-IFN–inducible lysosomal thiol reductase peptide, an almost universally observed and abundant endogenous peptide with HLA-A2⁺ cells.