Variant surface glycoprotein density defines an immune evasion threshold for African trypanosomes undergoing antigenic variation.

ABSTRACT: Trypanosoma brucei is a protozoan parasite that evades its host's adaptive immune response by repeatedly replacing its dense variant surface glycoprotein (VSG) coat from its large genomic VSG repertoire. While the mechanisms regulating VSG gene expression and diversification have been examined extensively, the dynamics of VSG coat replacement at the protein level, and the impact of this process on successful immune evasion, remain unclear. Here we evaluate the rate of VSG replacement at the trypanosome surface following a genetic VSG switch, and show that full coat replacement requires several days to complete. Using in vivo infection assays, we demonstrate that parasites undergoing coat replacement are only vulnerable to clearance via early IgM antibodies for a limited time. Finally, we s

SUBMITTER: Pinger J 

PROVIDER: S-EPMC5635023 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature