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The in vivo dynamics of antigenic variation in Trypanosoma brucei.

ABSTRACT: Trypanosoma brucei, a causative agent of African Sleeping Sickness, constantly changes its dense variant surface glycoprotein (VSG) coat to avoid elimination by the immune system of its mammalian host, using an extensive repertoire of dedicated genes. However, the dynamics of VSG expression in T. brucei during an infection are poorly understood. We have developed a method, based on de novo assembly of VSGs, for quantitatively examining the diversity of expressed VSGs in any population of trypanosomes and monitored VSG population dynamics in vivo. Our experiments revealed unexpected diversity within parasite populations and a mechanism for diversifying the genome-encoded VSG repertoire. The interaction between T. brucei and its host is substantially more dynamic and nuanced than previously expected.

SUBMITTER: Mugnier MR

PROVIDER: S-EPMC4514441 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature

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The in vivo dynamics of antigenic variation in Trypanosoma brucei.

Mugnier Monica R MR Cross George A M GA Papavasiliou F Nina FN

Science (New York, N.Y.) 20150301 6229

Trypanosoma brucei, a causative agent of African Sleeping Sickness, constantly changes its dense variant surface glycoprotein (VSG) coat to avoid elimination by the immune system of its mammalian host, using an extensive repertoire of dedicated genes. However, the dynamics of VSG expression in T. brucei during an infection are poorly understood. We have developed a method, based on de novo assembly of VSGs, for quantitatively examining the diversity of expressed VSGs in any population of trypano ...[more]

PMID: 25814582

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