ESTABLISHMENT OF A LONG TERM IN VITRO CULTIVATION SYSTEMOF ECHINOCOCCUS GRANULOSUS GERMINAL CELLS

ALBANI C. M.; ELISSONDO M. C.; CUMINO ANDREA; DENEGRI G. M.

Mar del Plata

Congreso; IX Congreso Argentino de Protozoologia y Enfermedades Parasitarias; 2011

Cystic echinococcosis is a zoonotic disease caused by the larval stage (metacestode) of the parasite Echinococcus granulosus which has a worldwide distribution and important medical and economic impact. An interesting topic of study in the developmental biology of flatworms is a population of totipotent stem cells denominated ?germinal cells? in the obligate parasitic trematodes and cestodes which is believed to possess the capacity to directly differentiate into all somatic cells and are regarded to be the only flatworm cell type that is mitotically active. With the aim of characterize the germinal cell cultivation system, the behavior in culture, survival to cryopreservation, karyotype and regeneration into mice were studied. We found germinal cells divided indefinitely for at least 2 years maintaining a high proliferation rate. After cryopreservation, the cells recovered with a survival of 80%. The chromosome assay showed that the number of chromosomes ranged from 18 to 72, nevertheless the main chromosome number was 36 which occupy 32% in the 100 metaphase cells counted. Moreover the cells were able to develop into complete cysts after being inoculated into mice which was confirmed by histopathological analysis. Based on the characteristics displayed for the E. granulosus germinal cell culture (e.g. cellular homogeneity, indefinitely multiplication, ability to regenerate a complete cyst), we propose that it would be a suitable in vitro model to lead developmental, regeneration and genetic engineering studies as a model for totipotent stem cells of platyhelmintes.