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Item rypanosoma cruzi induces apoptosis in ex vivo infected human chorionic villiAutores: Duaso, J.; Rojo, G.; Jana, E.; Galanti, N.; Cabrera, G.; Bosco, C.; Lopez-Munoz, R.; Maya, J.D.; Ferreira, J.; Kemmerling, U.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. (C) 2011 Elsevier Ltd. All rights reservedItem Participation of proteases in the infection of human Chorionic villi explants by Trypanosoma cruziAutores: Castillo, C.; Duaso, J.; Villarroel, A.; Cabrera, G.; Maya, J.D.; Galanti, N.; Kemmerling, U.Meeting AbstractItem Placentas from women with chagas' disease present similar histopathological change as ex vivov juman organic human chorionicc villiI infected with Trypanosoma cruziAutores: Duaso, J.; Bosco, C.; Maya, JD.; Galanti, N; Kemmerling, U.Item CONGENITAL INFECTION OF PROTOZOA: HISTOPATHOLOGICAL AND HISTOCHEMICAL ANALYSIS OF HUMAN CHORIONIC VILLI EXPLANTS INFECTED EX VIVO WITH TRYPANOSOMA CRUZI AND TOXOPLASMA GONDIIAutores: Liempi, A.; Droguett, D.; Castillo, C.; Sandoval, A.; Figueroa, P.; Galanti, N.; Maya, JD.; Kemmerling, U.Item Trypanasoma cruzi induces cellular proliferation in the trophoblastic cell line bewoAutores: Droguett, D.; Liempi, A.; Castillo, C.; Duaso, J.; Cerda, M.; Hartel, S.; Galanti, N.; Maya, J.D; Kemmerling, U.Chagas’ disease is caused by the haemophlagelated protozoan Trypanosoma cruzi (T. cruzi), which is able to cross the placental barrier and infect both the placenta and fetus. In ex vivo infected human chorionic villi, a low concentration of parasite induces activation of the Mitogen Activated Protein Kinase (MAPK) ERK1/2 signaling pathway, which plays an important role in cellular proliferation and differentiation. In order to determine whether the parasite is able to induce cellular proliferation in the trophoblast, BeWo cells were incubated in presence and absence of T. cruzi trypomastigotes (Y strain) (ratio parasite/BeWo cells 1:10) and in presence and absence of FBS for 2, 6, 12 and 24 hours. DNA synthesis was assayed by bromodeoxyuridine (BrdU) incorporation and determined by spectrometry and immunocytochemistry. Mitotic index was determined in DAPI stained samples and cell growth by detection of Nucleolar organizer regions (NORs) using silver staining (AgNORs). Parasites inside cells were identified by their nuclear and kinetoplast morphology. At least 500 cells were counted in each condition and analyzed using the MATLAB software; the statistical significance was analyzed by ANOVA followed by the Dunnetts post-test. The low concentration of T. cruzi used (mimicking women with chronic Chagas disease) induces a significant increase of BrdU incorporation into DNA and in the number of mitosis and of NORs in BeWo cells. We conclude that T. cruzi induces cell proliferation in the trophoblast; this process may form part of a “local placental antiparasite” defense mechanism. Financed by FONDECYT Projects Nº1120230 (UK), Nº 1130189 (JM), Nº1130113 (NG), 1120579 (SH). Support of CONICYT-PBCT Anillo ACT 112 and ICM (P09-015-F), Chile is also acknowledged.
