Parasitology Research

, Volume 96, Issue 6, pp 402–409 | Cite as

Mechanisms associated with Acanthamoeba castellanii (T4) phagocytosis

  • Selwa Alsam
  • James Sissons
  • Ricky Dudley
  • Naveed Ahmed KhanEmail author
Original Paper


Using fluorescein isothiocyanate (FITC)-labelled Escherichia coli, phagocytosis in Acanthamoeba is studied. This assay is based on the quenching effect of trypan blue on FITC-labelled E. coli. Only intracellular E. coli retain their fluorescence, which are easily discriminated from non-fluorescent adherent bacteria. Acanthamoeba uptake of E. coli is significantly reduced in the presence of genistein, a protein tyrosine kinase inhibitor. In contrast, sodium orthovanadate (protein tyrosine phosphatase inhibitor) increases bacterial uptake by Acanthamoeba. Treatment of Acanthamoeba with cytochalasin D (actin polymerization inhibitor) abolished the ability of Acanthamoeba to phagocytose E. coli suggesting that tyrosine kinase-mediated signaling may play a role in Acanthamoeba phagocytosis. In addition, we showed that phosphatidylinositol 3-kinase (PI3K) plays an important role in Acanthamoeba uptake of E. coli. Role of mannose-binding protein in Acanthamoeba phagocytosis is discussed further.


Genistein Sodium Orthovanadate Human Brain Microvascular Endothelial Cell Stress Fibre Formation Phagocytosis Assay 
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.



This work is supported by Faculty Research Grant, Birkbeck College, University of London, London, England, UK


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Copyright information

© Springer-Verlag 2005

Authors and Affiliations

  • Selwa Alsam
    • 1
  • James Sissons
    • 1
  • Ricky Dudley
    • 1
  • Naveed Ahmed Khan
    • 1
    Email author
  1. 1.School of Biological and Chemical Sciences, BirkbeckUniversity of LondonLondonUK

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