title: Early events related with the behaviour of Trypanosoma cruzi within an endocytic vacuole in mouse peritoneal macrophages.
abstract: Transmission electron microscopy was used to analyse the process of interaction of Trypanosoma cruzi with resident and activated mouse peritoneal macrophages. Initially, the parasites are located within a membrane-bounded endocytic vacuole. Lysosomes from the host cell fuse and discharge their content into the parasite-containing vacuole, as visualized by localization of horseradish peroxidase and acid phosphatase activity. Acridine orange was used to label secondary lysosomes in order to quantify the process of lysosome-phagosome fusion by fluorescence microscopy. The fusion index was higher for amastigote than for epimastigote and trypomastigote forms. Images were obtained showing that a few hours after ingestion of trypomastigote forms by the macrophages there is progressive disruption of the membrane lining the vacuole, until its complete disappearance.
authors.affiliation: Laboratório de Ultraestrutura Celular e Microscopia Eletrônica, Instituto de Biofísica Carlos Chagos Filho, Universidade Federal do Rio de Janeiro, Brasil.
authors.forename: T M
authors.initials: TM
authors.lastname: de Carvalho
authors.forename: W
authors.initials: W
authors.lastname: de Souza
mesh_terms: D000135:Acid Phosphatase / Q000378:metabolism; D000818:Animals; D004705:Endocytosis; D006651:Histocytochemistry; D006735:Horseradish Peroxidase; D002479:Inclusion Bodies / Q000378:metabolism / Q000469:parasitology* / Q000502:physiology; D008247:Lysosomes / Q000502:physiology / Q000648:ultrastructure; D008264:Macrophages / Q000378:metabolism / Q000502:physiology / Q000648:ultrastructure*; D051379:Mice; D008854:Microscopy, Electron; D010529:Peritoneal Cavity / Q000166:cytology; D014349:Trypanosoma cruzi / Q000502:physiology* / Q000648:ultrastructure
chemical_list: D006735:Horseradish Peroxidase; D000135:Acid Phosphatase