The strategies of the Theileria parasite: a new twist in host-pathogen interactions.
Theileria parasites infect and transform cells of the ruminant immune system. Continuous proliferation and survival of Theileria-transformed cells involves the well-orchestrated activation of several host-cell signalling pathways. Constitutive NF-kappa B (nuclear factor kappa B) activation is accomplished by recruiting the IKK (I kappa B kinase) complex, a central regulator of NF-kappa B pathways, to the surface of the transforming schizont, where it becomes permanently activated. Constitutive activation of the PI-3K-PKB [phosphoinositide 3-kinase-(Akt) protein kinase B] pathway is likely to be indirect and is essential for continuous proliferation. Theileria-transformed T cells express a range of anti-apoptotic proteins that can be expected to provide protection against apoptosis induced by death receptors, as well as cellular control mechanisms that are mobilised to eliminate cells that entered a cycle of uncontrolled proliferation.
Dobbelaere
Dirk A E
DA
Division of Molecular Pathology, Institute of Animal Pathology, University of Bern, Länggassstrasse 122, CH-3012 Bern, Switzerland. dirk.dobbelaere@itpa.unibe.ch
Küenzi
Peter
P
D000818:Animals; D017209:Apoptosis / Q000276:immunology*; D006801:Humans; D051550:I-kappa B Kinase; D020935:MAP Kinase Signaling System / Q000276:immunology; D051379:Mice; D016328:NF-kappa B / Q000276:immunology; D019869:Phosphatidylinositol 3-Kinases / Q000276:immunology; D017346:Protein Serine-Threonine Kinases / Q000276:immunology*; D011518:Proto-Oncogene Proteins / Q000276:immunology*; D051057:Proto-Oncogene Proteins c-akt; D016794:Theileria / Q000276:immunology*; D013801:Theileriasis / Q000276:immunology / Q000469:parasitology
D051550:I-kappa B Kinase; D016328:NF-kappa B; D019869:Phosphatidylinositol 3-Kinases; D017346:Protein Serine-Threonine Kinases; D011518:Proto-Oncogene Proteins; D051057:Proto-Oncogene Proteins c-akt; C494918:AKT1 protein, human; C496559:CHUK protein, human; C496564:Chuk protein, mouse; C496560:IKBKB protein, human; C496565:IKBKE protein, human; C496562:Ikbkb protein, mouse; C496566:Ikbke protein, mouse