Secreted by MØ and T-cells.

Local: TNF acts on endothelial cells to recruit PMNs and Monocytes to the site of infection.

Systemic: Fever. Very high levels of TNF cause septic shock.

Secreted by MØ, endothelial cells.

IL-1 acts on endothelial cells near a site of infection to increase expression of selectin and integrin-ligand for binding and recruitment (diapedesis) of PMNs and Monocytes to the site of infection.

Powerful inducer of inflammation.

Secreted by MØ and Dendritic cells.

IL-12 activates NK cells and enhances their cytotoxic activity.

Secreted by NK cells.

IFN-γ activates MØ and enhances their ability to kill phagocytosed pathogens by increasing their production of ROS and NO.

Secreted by MØ and Dendritic cells.

• IFN-α activates NK cells and enhances cytotoxic function.
• Inhibit viral replication.
• Increase MHC I expression on all cells.

Secreted by MØ.

IL-15 causes NK cell proliferation and development.

Secreted by MØ and Dendritic cells.

Chemokines activate circulating PMN and Monocytes causing increased affinity of integrin for its ligand (diapedesis) and chemotaxis towards the site of infection.

Secreted by fibroblasts.

• NK cell activation and increased cytotoxicity.
• Inhibits viral replication.
• Increases MHC I expression on all cells.