IFNG and influenza: Secreted cytokines following spleen harvest and antigen restimulation (1 μg/mL whole influenza antigen, detergent split A/Victoria or whole HK68 as indicated) were measured after 72 h of stimulation by MesoScale Discovery (MSD) U-PLEX Assay Platform (MesoScale Diagnostics) to detect mouse IFNγ, IL-17, TNFα, IL-2, and IL-5.