TNF and infection: Inhibits neuraminidase activity, restrains the infection by interfering with endocytosis, increases the levels of IFN-γ and IL-10 in serum, decreases the levels of TNF-α and IL-6, alleviates the pathological changes of lung tissue and decreases the lung index of mice infected by A/swine/Tianjing/14/2009(H1N1).