Entamoeba histolytica: lipid rafts are involved in adhesion of trophozoites to host extracellular matrix components.

نویسندگان

  • K Mittal
  • B H Welter
  • L A Temesvari
چکیده

Adhesion is an important virulence function for Entamoeba histolytica, the causative agent of amoebic dysentery. Lipid rafts, cholesterol-rich domains, function in compartmentalization of cellular processes. In E. histolytica, rafts participate in parasite-host cell interactions; however, their role in parasite-host extracellular matrix (ECM) interactions has not been explored. Disruption of rafts with a cholesterol extracting agent, methyl-beta-cyclodextrin (MbetaCD), resulted in inhibition of adhesion to collagen, and to a lesser extent, to fibronectin. Replenishment of cholesterol in MbetaCD-treated cells, using a lipoprotein-cholesterol concentrate, restored adhesion to collagen. Confocal microscopy revealed enrichment of rafts at parasite-ECM interfaces. A raft-resident adhesin, the galactose/N-acetylgalactosamine-inhibitable lectin, mediates interaction to host cells by binding to galactose or N-acetylgalactosamine moieties on host glycoproteins. In this study, galactose inhibited adhesion to collagen, but not to fibronectin. Together these data suggest that rafts participate in E. histolytica-ECM interactions and that raft-associated Gal/GalNAc lectin may serve as a collagen receptor.

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عنوان ژورنال:
  • Experimental parasitology

دوره 120 2  شماره 

صفحات  -

تاریخ انتشار 2008