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A latent ability to persist: differentiation in Toxoplasma gondii

Abstract

A critical factor in the transmission and pathogenesis of Toxoplasma gondii is the ability to convert from an acute disease-causing, proliferative stage (tachyzoite), to a chronic, dormant stage (bradyzoite). The conversion of the tachyzoite-containing parasitophorous vacuole membrane into the less permeable bradyzoite cyst wall allows the parasite to persist for years within the host to maximize transmissibility to both primary (felids) and secondary (virtually all other warm-blooded vertebrates) hosts. This review presents our current understanding of the latent stage, including the factors that are important in bradyzoite induction and maintenance. Also discussed are the recent studies that have begun to unravel the mechanisms behind stage switching.

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Acknowledgements

The authors thank Dr. Michael White for his careful and critical review of our manuscript. Research in the laboratories of Drs. Sullivan and Kim is supported by Grants from the National Institutes of Health: AI116496 and AI124723 (WJS), R01AI087625 (KK), and AI092801 (to KK and WJS). This manuscript is dedicated to the memory of Dr. Zoi Tampaki who was a dedicated scientist, a valued colleague, and a beloved friend. We miss you every day.

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Correspondence to Victoria Jeffers.

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Jeffers, V., Tampaki, Z., Kim, K. et al. A latent ability to persist: differentiation in Toxoplasma gondii. Cell. Mol. Life Sci. 75, 2355–2373 (2018). https://doi.org/10.1007/s00018-018-2808-x

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Keywords

  • Toxoplasma
  • Toxoplasmosis
  • Differentiation
  • Encystation
  • Tachyzoite
  • Bradyzoite
  • Latency
  • Gene regulation
  • Epigenetics
  • Immunity