title: Colonization of Rhodnius prolixus gut by Trypanosoma cruzi involves an extensive parasite killing.
abstract: Trypanosoma cruzi, the etiological agent of Chagas disease, is ingested by triatomines during their bloodmeal on an infected mammal. Aiming to investigate the development and differentiation of T. cruzi inside the intestinal tract of Rhodnius prolixus at the beginning of infection we fed insects with cultured epimastigotes and blood trypomastigotes from infected mice to determine the amount of recovered parasites after ingestion. Approximately 20% of the ingested parasites was found in the insect anterior midgut (AM) 3 h after feeding. Interestingly, a significant reduction (80%) in the numbers of trypomastigotes was observed after 24 h of infection suggesting that parasites were killed in the AM. Moreover, few parasites were found in that intestinal portion after 96 h of infection. The evaluation of the numbers of parasites in the posterior midgut (PM) at the same periods showed a reduced parasite load, indicating that parasites were not moving from the AM. Additionally, incubation of blood trypomastigotes with extracts from R. prolixus AMs revealed that components of this tissue could induce significant death of T. cruzi. Finally, we observed that differentiation from trypomastigotes to epimastigotes is not completed in the AM; instead we suggest that trypomastigotes change to intermediary forms before their migration to the PM, where differentiation to epimastigotes takes place. The present work clarifies controversial points concerning T. cruzi development in insect vector, showing that parasite suffers a drastic decrease in population size before epimastigonesis accomplishment in PM.
authors.affiliation: Vector Behavior and Pathogen Interaction Group,Centro de Pesquisas René Rachou,Fiocruz,Av. Augusto de Lima,1715,Belo Horizonte,Minas Gerais,Brazil.
authors.forename: Roberta Carvalho
authors.initials: RC
authors.lastname: Ferreira
authors.affiliation: Laboratory of Functional Genomic,Instituto Carlos Chagas,Fiocruz,Rua Prof. Algacyr Munhoz Mader,3775, 81350-010 Curitiba,Paraná,Brazil.
authors.forename: Rafael Luis
authors.initials: RL
authors.lastname: Kessler
authors.affiliation: Vector Behavior and Pathogen Interaction Group,Centro de Pesquisas René Rachou,Fiocruz,Av. Augusto de Lima,1715,Belo Horizonte,Minas Gerais,Brazil.
authors.forename: Marcelo Gustavo
authors.initials: MG
authors.lastname: Lorenzo
authors.affiliation: Instituto de Ciências Biológicas,Universidade Federal de Minas Gerais,Av. Pres. Antônio Carlos 6627,Pampulha,31270-901 Belo Horizonte,Minas Gerais,Brazil.
authors.forename: Rafaela Magalhães Macedo
authors.initials: RM
authors.lastname: Paim
authors.affiliation: Vector Behavior and Pathogen Interaction Group,Centro de Pesquisas René Rachou,Fiocruz,Av. Augusto de Lima,1715,Belo Horizonte,Minas Gerais,Brazil.
authors.forename: Luciana De Lima
authors.initials: Lde L
authors.lastname: Ferreira
authors.affiliation: Laboratory of Functional Genomic,Instituto Carlos Chagas,Fiocruz,Rua Prof. Algacyr Munhoz Mader,3775, 81350-010 Curitiba,Paraná,Brazil.
authors.forename: Christian Macagnan
authors.initials: CM
authors.lastname: Probst
authors.affiliation: Instituto de Ciências Biológicas,Universidade Federal de Minas Gerais,Av. Pres. Antônio Carlos 6627,Pampulha,31270-901 Belo Horizonte,Minas Gerais,Brazil.
authors.forename: Juliana
authors.initials: J
authors.lastname: Alves-Silva
authors.affiliation: Vector Behavior and Pathogen Interaction Group,Centro de Pesquisas René Rachou,Fiocruz,Av. Augusto de Lima,1715,Belo Horizonte,Minas Gerais,Brazil.
authors.forename: Alessandra Aparecida
authors.identifier: http://orcid.org/0000-0002-9162-2731
authors.initials: AA
authors.lastname: Guarneri
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D014355:Chagas Disease / Q000097:blood / Q000469:parasitology* / Q000635:transmission; D016054:DNA, Protozoan / Q000737:chemistry / Q000302:isolation & purification; D007303:Insect Vectors / Q000469:parasitology*; D051379:Mice; D009758:Nymph / Q000469:parasitology; D060888:Real-Time Polymerase Chain Reaction; D012239:Rhodnius / Q000469:parasitology*; D014349:Trypanosoma cruzi / Q000235:genetics / Q000254:growth & development*
chemical_list: D016054:DNA, Protozoan
keywords: Chagas disease; Rhodnius prolixus; Trypanosoma cruzi; epimastigogenesis; trypanosome