The strong correlation between TNF-α and IL-10 levels in the CSF indicates the activation of distinct cellular compartments in the CNS during infection, and identification of the CNS cellular sources of IL-10, TNF-α and TGF-β in HAT will require further work in model systems, and to determine if distinct subsets of brain macrophages are involved in inflammatory/counterinflammatory regulation as has been observed in in vitro models of murine brain macrophage activation [41]. This evidence concerns the gene TNF and infection.