Academic Journals Database
Disseminating quality controlled scientific knowledge

Schistosoma mansoni: cambios ultraestructurales durante la transformación del miracidio in vitro

Author(s): Emilia E. Barrios | Héctor J. Finol | Víctor Delgado | Wolfan Araque

Journal: Salus Online
ISSN 1316-7138

Volume: 8;
Issue: 1;
Start page: 17;
Date: 2004;
VIEW PDF   PDF DOWNLOAD PDF   Download PDF Original page

Keywords: Schistosoma mansoni | transmission electron microscopy | miracidia

Ultrastructural changes were assessed during in vitro transformation ofmiracidia (M) of Schistosoma mansoni. Morphological characteristics werebased on viability (protonefrigial integrity and uptake of trypan blue dye), larvalsize and degree of differentiation into mother sporocysts (MS) during incubationin RPMI-1640 by 30 min followed by 7 days in Hansen medium. Lightmicroscopy showed that M first step of transformation occurs within 30 min,with loss of movement and ciliary epidermal plates. Transformed MS areextended, with worm-like movement and active flame cells; viability was 76% at5 days and 50% at 11 days, and increased three-fold in length reaching 300 µmduring the first 16 days. Transmission Electron Microscopy at 24 h of culturerevealed significant structural changes in tegumental composition anddistribution; free polysomes and microvilli were found in the external layer ofthe tegument. At day 7 the external membrane of MS was thin and interiorgerminative bags were observed, with electron-dense proteic granules. Theprotonefrigial system remained intact at 24 h of culture, constituted by flamecells with 11 pairs of peripheral microtubules. It is concluded that miracidialtransformation in cell-free culture results in surface alteration, and involvesultrastructural changes

Tango Jona
Tangokurs Rapperswil-Jona

RPA Switzerland

Robotic Process Automation Switzerland