TNF and human African trypanosomiasis: Whereas TNF is able to directly kill long slender bloodstream forms of the protozoan parasite Trypanosoma brucei brucei causing sleeping sickness, by means of lysosomal lysis (Lucas et al., 1994; Magez et al., 1997; Daulouède et al., 2001) upon lectin-like recognition of their variant surface glycoprotein, lymphotoxin-α, which has a similar conformation as TNF and which can bind to TNF receptors, failed to do so.