title: Cell-matrix interactions of Entamoeba histolytica and E. dispar. A comparative study by electron-, atomic force- and confocal microscopy.
abstract: Invasion of tissues by Entamoeba histolytica is a multistep process that initiates with the adhesion of the parasite to target tissues. The recognition of the non-invasive Entamoeba dispar as a distinct, but closely related protozoan species raised the question as to whether the lack of its pathogenic potential could be related to a weaker adhesion due to limited cytoskeleton restructuring capacity. We here compared the adhesion process of both amebas to fibronectin through scanning, transmission, atomic force, and confocal microscopy. In addition, electrophoretic and western blot assays of actin were also compared. Adhesion of E. histolytica to fibronectin involves a dramatic reorganization of the actin network that results in a tighter contact to and the subsequent focal degradation of the fibronectin matrix. In contrast, E. dispar showed no regions of focal adhesion, the cytoskeleton was poorly reorganized and there was little fibronectin degradation. In addition, atomic force microscopy using topographic, error signal and phase modes revealed clear-cut differences at the site of contact of both amebas with the substrate. In spite of the morphological and genetic similarities between E. histolytica and E. dispar the present results demonstrate striking differences in their respective cell-to-matrix adhesion processes, which may be of relevance for understanding the invasive character of E. histolytica.
authors.affiliation: Department of Infectomics and Molecular Pathogenesis, Centro de Investigación y de Estudios Avanzados, Apartado Postal 14-740, Mexico City, Mexico. Electronic address: daniel_talamas@hotmail.com.
authors.forename: Daniel
authors.initials: D
authors.lastname: Talamás-Lara
authors.affiliation: Department of Infectomics and Molecular Pathogenesis, Centro de Investigación y de Estudios Avanzados, Apartado Postal 14-740, Mexico City, Mexico. Electronic address: ptr@cinvestav.mx.
authors.forename: Patricia
authors.initials: P
authors.lastname: Talamás-Rohana
authors.affiliation: Department of Physics, Centro de Investigación y de Estudios Avanzados, Apartado Postal 14-740, Mexico City, Mexico. Electronic address: rogelio@fis.cinvestav.mx.
authors.forename: Rogelio Jaime
authors.initials: RJ
authors.lastname: Fragoso-Soriano
authors.affiliation: Department of Infectomics and Molecular Pathogenesis, Centro de Investigación y de Estudios Avanzados, Apartado Postal 14-740, Mexico City, Mexico. Electronic address: mespinosac@cinvestav.mx.
authors.forename: Martha
authors.initials: M
authors.lastname: Espinosa-Cantellano
authors.affiliation: Department of Infectomics and Molecular Pathogenesis, Centro de Investigación y de Estudios Avanzados, Apartado Postal 14-740, Mexico City, Mexico. Electronic address: bchavez@cinvestav.mx.
authors.forename: Bibiana
authors.initials: B
authors.lastname: Chávez-Munguía
authors.affiliation: Department of Infectomics and Molecular Pathogenesis, Centro de Investigación y de Estudios Avanzados, Apartado Postal 14-740, Mexico City, Mexico. Electronic address: goroa@cinvestav.mx.
authors.forename: Arturo
authors.initials: A
authors.lastname: González-Robles
authors.affiliation: Department of Infectomics and Molecular Pathogenesis, Centro de Investigación y de Estudios Avanzados, Apartado Postal 14-740, Mexico City, Mexico. Electronic address: amartine@cinvestav.mx.
authors.forename: Adolfo
authors.initials: A
authors.lastname: Martínez-Palomo
mesh_terms: D000818:Animals; D002450:Cell Communication / Q000502:physiology*; D004747:Entamoeba / Q000254:growth & development / Q000378:metabolism* / Q000648:ultrastructure; D004748:Entamoeba histolytica / Q000254:growth & development / Q000378:metabolism* / Q000648:ultrastructure; D005353:Fibronectins / Q000378:metabolism*; D018625:Microscopy, Atomic Force / Q000379:methods*; D018613:Microscopy, Confocal / Q000379:methods*; D008855:Microscopy, Electron, Scanning / Q000379:methods*
chemical_list: D005353:Fibronectins
keywords: Actin; Adhesion; Cytoskeleton; Entamoeba dispar; Entamoeba histolytica; Fibronectin