title: [Massive production of Entamoeba histolytica cysts under axenic conditions].
abstract: After an exponential phase of growth, HK9 strain amebas, kept in the axenic medium PEHPS, spontaneously acquire a form morphologically similar to various natural cysts, as well as a resistance to hypotonic shock, due to the effect of a wall, partially composed of polysaccharides. The number of differentiated amebas increases gradually, although their viability diminishes, in function of the incubation time. On the ninth day, 96% of the population is made up of these cells, although only 6% are viable. The ultramicroscopic structure of the great majority of differentiated amebas corresponds to that of immature cysts. These, and the PEHPS medium, constitute a good model for a characterization of the start of the differentiation of E. histolytica, and open the opportunity of obtaining in axenic conditions, massive cultures of mature cysts.
authors.affiliation: División de Biología Celular, Instituto Mexicano del Seguro Social, Monterrey, N.L.
authors.forename: S
authors.initials: S
authors.lastname: Said-Fernández
authors.forename: B D
authors.initials: BD
authors.lastname: Mata-Cárdenas
authors.forename: M T
authors.initials: MT
authors.lastname: González-Garza
authors.forename: J
authors.initials: J
authors.lastname: Mora-Galindo
authors.forename: J
authors.initials: J
authors.lastname: Ruiz-Ordóñez
authors.forename: L
authors.initials: L
authors.lastname: Navarro-Marmolejo
mesh_terms: D000818:Animals; D003470:Culture Media; D004748:Entamoeba histolytica / Q000254:growth & development / Q000648:ultrastructure*; D005856:Germ-Free Life / Q000502:physiology*; D008855:Microscopy, Electron, Scanning; D008858:Microscopy, Phase-Contrast; D009997:Osmotic Pressure
chemical_list: D003470:Culture Media
vernacular_title: Producción masiva de quistes de Entamoeba histolytica en condiciones axénicas.