To examine the induction of CMI responses against influenza in immunized mice, the spleens were collected four weeks following the second immunization and analyzed for an HA-specific CMI response using anti-influenza CD8 pentamer staining for the HA518 epitope conserved between H5 and H9, but not H7 subtypes, and interferon-gamma (IFN-γ)-ELISpot assays. Here, CD8A is linked to influenza.