Programmed Cell Death and the Enteric Protozoan Parasite Blastocystis hominis: Perspectives and Prospects

  • Kevin S. W. Tan
Part of the Molecular Biology Intelligence Unit book series (MBIU)


The propensity for unicellular eukaryotes to undergo programmed cell death (PCD) has been well documented in recent years. This fascinating yet somewhat counterintuitive phenomenon has been reported to occur for many species of the parasitic Protozoa. Among the luminal Protozoa, PCD in Blastocystis has been the best characterized. This intestinal protozoan parasite has been shown to exhibit a number of PCD features that are apoptotic or non-apoptotic. Caspase-like activity and mitochondria are involved in Blastocystis PCD and have been linked to DNA fragmentation in the parasite. PCD, however, can also occur in the absence of mitochondrial and caspase involvement and DNA fragmentation. This indicates that multiple cell death pathways exist in Blastocystis, highlighting the cellular complexity of the seemingly simple Protozoa. Despite advances in our understanding of Blastocystis PCD, specific genes and proteins associated with this process have yet to be identified. Recent work has shown that Blastocystis can induce apoptosis in intestinal epithelial cells in vitro. Interplay of cell death between host and parasite should provide interesting and novel insights into host-pathogen interactions in vivo.


Programme Cell Death Apoptotic Body Cell Shrinkage Central Vacuole Cell Death Differ 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Landes Bioscience and Springer Science+Business Media 2008

Authors and Affiliations

  1. 1.Laboratory of Molecular and Cellular Parasitology, Department of MicrobiologyYong Loo Lin School of Medicine National University of SingaporeSingapore

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