TNF and infection: Upon infection, microglia, macrophages and astrocytes become activated and secrete several pro-inflammatory cytokines and chemokines [i.e., tumor necrosis factor-α (TNFα), interleukin-1β (IL-1β), interferon-γ (IFNγ), C-C motif chemokine ligand 2 (CCL2), C-X-C motif chemokine 10 (CXCL10)] and neurotoxins [i.e., arachidonic/quinolinic acid and metabolites, platelet activating factor, neurotoxic amines, reactive oxygen species (ROS), nitric oxide (NO) and glutamate]3,4,9.