LEP and infection: Global deficiency of leptin receptor (db/db) have worsened survival following influenza A infection.Leptin receptor deficiency impaired viral clearance & diminished the IFN-γ levels.Loss of leptin receptor within lung epithelium or within macrophages is not associated with worsened lung injury or mortality following infection.Decrease proinflammatory cytokines IL-6 and IL-1β level and increase survival.Disruption of leptin signaling in T cells limits worsened the pH1N1 dependent mortality and infection severity.