title: Extracellular ATP induces cell death in CD4+/CD8+ double-positive thymocytes in mice infected with Trypanosoma cruzi.
abstract: In the acute phase of Trypanosoma cruzi infection, there is dramatic atrophy of the thymus. However, the pathways involved in this change have not yet been identified. This event is mainly characterized by a massive loss of cortical CD4+/CD8+ double-positive cells, but also by other structural and functional alterations in the organ. A number of molecules, including extracellular ATP, have been suggested to play a role in the selective processes that take place in the thymus. ATP and analogues trigger many different cellular responses in thymocytes and other cell types, such as the opening of plasma membrane cation channels and a pore that may induce cell death. Herein, we investigated the possible involvement of extracellular ATP in thymus atrophy induced by infection with T. cruzi. We observed that ATP induces an increase in plasma membrane permeabilization and cellular death in CD4+/CD8+ double-positive thymocytes collected from infected mice during the atrophy phase. No differences were observed prior to the atrophy phase or during the chronic phase. Our results indicate that P2Z/P2X7 receptors may play a central role in thymus atrophy during T. cruzi infection.
authors.affiliation: Laboratório de Imunobiofísica, Instituto de Biofísica Carlos Chagas Filho, UFRJ, Bloco G do CCS, Cidade Universitária, Ilha do Fundão, 21941-590 Rio de Janeiro, Brazil.
authors.forename: Marcio
authors.initials: M
authors.lastname: Mantuano-Barradas
authors.forename: Andréa
authors.initials: A
authors.lastname: Henriques-Pons
authors.forename: Tânia C
authors.initials: TC
authors.lastname: Araújo-Jorge
authors.forename: Francesco
authors.initials: F
authors.lastname: Di Virgilio
authors.forename: Robson
authors.initials: R
authors.lastname: Coutinho-Silva
authors.forename: Pedro M
authors.initials: PM
authors.lastname: Persechini
mesh_terms: D000255:Adenosine Triphosphate / Q000494:pharmacology*; D000818:Animals; D017209:Apoptosis; D015704:CD4 Antigens / Q000378:metabolism; D016827:CD8 Antigens / Q000378:metabolism; D014355:Chagas Disease / Q000276:immunology / Q000473:pathology*; D051379:Mice; D013950:Thymus Gland / Q000187:drug effects* / Q000276:immunology / Q000473:pathology; D014349:Trypanosoma cruzi
chemical_list: D015704:CD4 Antigens; D016827:CD8 Antigens; D000255:Adenosine Triphosphate