Figure 3. Interferon-γ (IFN-γ) or tumor necrosis factor-α (TNFα) production by influenza A virus (IAV)-specific lung CD4+ T-cells.
Lungs from mice infected with PR/8 and HK/X31 IAVs, as previously described in Figure 1, were homogenized and stimulated for 6 hrs with nucleoprotein (NP)311–325 peptide, a MHC Class II restricted PR/8 IAV epitope. The % of NP311–325-specific IFN-γ+ (A) or TNFα+ (B) producing lung CD4+ T-cells and the frequencies of NP311–325-specific lung CD4+ T-cells (C) were determined in B6, MyD88−/− and TLR7−/− mice (expressed as the percentage of CD3+ T-cells). Values shown (A & B) are the % of IFN-γ+ or TNFα+ NP311–325-specific CD4+ T cells minus unstimulated background (expressed as the percentage of CD4+ T-cells). Bars are median values. *p<0.05 compared to NP311–325-specific B6 lung CD4+ T-cells.