Antigenic variation and the African trypanosome genome

JE Donelson - Acta tropica, 2003 - Elsevier
African trypanosomes are protozoan parasites that reside in the mammalian bloodstream
where they constantly confront the immune responses directed against them. They keep one-
step-ahead of the immune system by continually switching from the expression of one
variant surface glycoprotein (VSG) on their surface to the expression of another
immunologically distinct VSG—a phenomenon called antigenic variation. About 1000 VSG
genes (VSGs) and pseudo-VSGs are scattered throughout the trypanosome genome, all of …