Jeremy Sternberg
8.8 Summary
African trypanosome immunological interactions with the host are defined by the VSG molecule and its GPI anchor. Trypanosomes effectively evade humoral responses through a combination of antigenic variation and rapid membrane recycling of their VSG and any bound antibodies. However, the VSG and GPI an- chor components are potent non-specific activators of a type 1 innate immune response that leads to immunopathology through a sustained inflammatory re- sponse syndrome. At the same time, a truncated VSG gene product, SRA, is able to neutralise the potent innate humoral factor Apo-L1 present in human serum.
Antigenic variation, together with the destruction of marginal zone and follic- ular B cell compartments in the spleen, renders the likelihood of an effective vaccine very low.
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