Novel expression-linked copies of the genes for variant surface antigens in trypanosomes

Pathogenic African trypanosomes evade the immune system of their mammalian hosts by the sequential expression of alternative cell-surface glycoproteins (reviewed in refs 1, 2). Variant surface glycoproteins (VSGs) purified3 from cloned variants of Trypanosoma brucei have similar molecular weights (about 60,000), but differ in amino acid composition3, N… CONTINUE READING