Importantly, T-cell activating cytokine IL-2 was significantly elevated in the vaccinated animals during acute infection when compared to the controls (p = 0.0264), as was leukocyte chemoattractant RANTES (p = 0.0430) (Fig 4A), which is produced by epithelial cells in response to influenza infection in order to recruit leukocytes to the site of infection [56]. The gene discussed is CCL5; the disease is infection.