title: Trypanosoma cruzi induces apoptosis in ex vivo infected human chorionic villi.
abstract: Chagas' disease, produced by the haemoflagellated protozoan Trypanosoma cruzi (T. cruzi), is one of the most frequent endemic diseases in Latin America. In spite that in the past few years T. cruzi congenital transmission has become of epidemiological importance, studies about this mechanism of infection are scarce. The placental tissue undergoes apoptosis throughout gestation, as part of its normal turnover. On the other hand, it is known that T. cruzi induces, delays or inhibits apoptosis in other mammalian tissues. In order to determine the effect of parasite invasion on normal apoptosis in the placenta, explants of human chorionic villi were incubated with 105 trypomastigotes for 24 h. Effective infection was tested by visualizing T. cruzi antigens in histological preparations and by PCR. Upon infection, apoptotic cell death was determined by light and transmission electron microscopy, TUNEL analysis, measurement of caspase-3 like activity and immunohistochemical detection of caspase 3 cleaved cytokeratin 18. Our results clearly show that T. cruzi induces apoptosis in the chorionic villi and suggest that this is one of mechanisms used by the parasite to insure infection and invasion of human placenta and fetus.
authors.affiliation: Programa de Anatomía y Biología del Desarrollo, Instituto de Ciencias Biomédicas, Universidad de Chile, Santiago.
authors.forename: J
authors.initials: J
authors.lastname: Duaso
authors.forename: G
authors.initials: G
authors.lastname: Rojo
authors.forename: F
authors.initials: F
authors.lastname: Jaña
authors.forename: N
authors.initials: N
authors.lastname: Galanti
authors.forename: G
authors.initials: G
authors.lastname: Cabrera
authors.forename: C
authors.initials: C
authors.lastname: Bosco
authors.forename: R
authors.initials: R
authors.lastname: López-Muñoz
authors.forename: J D
authors.initials: JD
authors.lastname: Maya
authors.forename: J
authors.initials: J
authors.lastname: Ferreira
authors.forename: U
authors.initials: U
authors.lastname: Kemmerling
mesh_terms: D000818:Animals; D017209:Apoptosis; D053148:Caspase 3 / Q000378:metabolism; D014355:Chagas Disease / Q000378:metabolism / Q000473:pathology*; D002522:Chlorocebus aethiops; D002824:Chorionic Villi / Q000469:parasitology / Q000473:pathology*; D018920:Coculture Techniques; D053938:DNA Fragmentation; D005260:Female; D006790:Host-Parasite Interactions; D006801:Humans; D053538:Keratin-18 / Q000378:metabolism; D011247:Pregnancy; D014349:Trypanosoma cruzi / Q000502:physiology*; D014709:Vero Cells
chemical_list: D053538:Keratin-18; C505407:CASP3 protein, human; D053148:Caspase 3