Diversity of Epitope and Cytokine Profiles for Primary and Secondary Influenza A Virus-Specific CD8+ T Cell Responses

摘要: Screening with the flow cytometric IFN-γ assay has led to identification of a new immunogenic peptide (SSYRRVPGI) from influenza PB1 polymerase (PB1703–711) and mimotope (ISPLMVAYM) PB2 (PB2198–206). CD8+ T cells specific for KbPB1703 make both TNF-α following stimulation peptides. The KbPB1703+ population kills PB2198-pulsed targets, but cell lines stimulated PB2198 neither bind tetramer nor become CTL. This CD8+KbPB1703+ is prominent in primary response an H3N2 virus, although it much less obvious secondary challenge H1N1-primed mice. Even so, we can now account >40% pneumonia >85% those present after → H1N1 challenge. Profiles staining vitro have been traced four most peptides through responses into long-term memory. DbNP366 epitope that immunodominant shows lowest frequencies IFN-γ+TNF-α+ >6 wk, intensity also low first 3 wk. By 11 however, IFN-γ/TNF-α profiles look be similar all epitopes. At least by criterion cytokine production, there considerable epitope-related functional diversity virus-specific response. results provide cautionary tale using approach identity antigenic