epidermal-growth-factor and Giardiasis

Topics: Anaphylaxis; Animals; Epidermal Growth Factor; Giardiasis; Humans; Intestines; Microvilli; Yersinia Infections

In order to improve our understanding of the host cell-parasite interactions in giardiasis, this study assessed the effects of Giardia lamblia on epithelial permeability and tight junctional ZO-1, determined whether epidermal growth factor (EGF) may affect Giardia-induced epithelial injury, and evaluated if EGF modulates epithelial colonization by live G. lamblia trophozoites. Permeability was assessed in assays of trans-epithelial fluxes of FITC-dextran, and ZO-1 integrity was characterized by confocal laser immunofluorescence microscopy in confluent epithelial cell monolayers. G. lamblia significantly increased paracellular permeability and disrupted tight-junctional ZO-1 of a novel non-transformed human small intestinal epithelial cell line (SCBN). Pre-treatment with EGF prevented the development of these abnormalities and significantly inhibited attachment of live trophozoites to the enterocytes, independently of a direct microbiocidal action. These findings demonstrate that G. lamblia may cause intestinal pathophysiology by disrupting tight junctional ZO-1 and increasing epithelial permeability. Apical administration of EGF prevents these abnormalities, and reduces epithelial colonization by the live parasites.

Topics: Animals; Cell Membrane Permeability; Epidermal Growth Factor; Epithelial Cells; Giardia lamblia; Giardiasis; Host-Parasite Interactions; Humans; Intestinal Mucosa; Intestine, Small; Membrane Proteins; Microscopy, Confocal; Phosphoproteins; Tight Junctions; Zonula Occludens-1 Protein