Researchers from the University of Brussels, Gosselies, Belgium and
colleagues have discovered a strategy that Trypanosoma brucei
rhodesiense, the parasite that causes sleeping sickness, uses to overcome
natural human defenses against infection (Nature.
Human serum contains a molecule called trypanosome lytic factor that
can prevent infection. Some strains of the parasite make a shortened version
of a cell surface molecule called serum resistance-associated protein (SRA)
that allows them to evade this defense, but the identity of the lytic factor
and the exact molecular mechanism of this evasion were unknown.
Stephenson J. "Atypical" Pneumonia Alert. JAMA. 2003;289(14):1774. doi:10.1001/jama.289.14.1774-a