TNF and infection: In a typical response, circulating monocytes are recruited to the site of infection upon signaling by damage-associated and pathogen-associated molecular patterns (DAMPs and PAMPs), and proinflammatory cytokines such as IL-6, IFNγ, and TNFα; these arriving monocytes initially differentiate, or polarize, toward proinflammatory (M1) macrophages (17–25).