Trypanosomiasis vaccine

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A Trypanosomiasis vaccine is a vaccine against trypanosomiasis. No effective vaccine currently exists, but development of a vaccine is the subject of current research.

The Bill & Melinda Gates Foundation has been involved in funding research conducted by the Sabin Vaccine Institute and others. [1]

There are many obstacles to development of such a vaccine. One obstacle is variant surface glycoprotein which makes it difficult for the immune system to recognize the infectious organism. [2] Also, Trypanosoma brucei has a direct inhibitory effect upon B cells. [3]

It has been suggested that these challenges could be overcome by a vaccine against the initial antigens, [4] or generating an immune response against the cysteine protease (for example, cruzipain). [5] [6]

An effective vaccine was achieved in 2021 using a mouse model of infection with Trypanosoma vivax . [7]

See also

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Animal trypanosomiasis

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Variant surface glycoprotein

Variant surface glycoprotein (VSG) is a ~60kDa protein which densely packs the cell surface of protozoan parasites belonging to the genus Trypanosoma. This genus is notable for their cell surface proteins. They were first isolated from Trypanosoma brucei in 1975 by George Cross. VSG allows the trypanosomatid parasites to evade the mammalian host's immune system by extensive antigenic variation. They form a 12–15 nm surface coat. VSG dimers, ~90% of all cell surface protein. It also makes up ~10% of total cell protein. For this reason, these proteins are highly immunogenic and an immune response raised against a specific VSG coat will rapidly kill trypanosomes expressing this variant. However, with each cell division there is a possibility that the progeny will switch expression to change the VSG that is being expressed. VSG has no prescribed biochemical activity.

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  1. "US Fraunhofer Center receives Grant from the Bill & Melinda Gates Foundation-Intellectual Property" . Retrieved 2009-01-15.
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