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Waldeck B, Schaub GA. "Natural infections" with Trypanosoma cruzi via the skin of mice: size of mouthparts of vectors and numbers of invading parasites. Parasitol Res 2022; 121:2033-2041. [PMID: 35507065 PMCID: PMC9192721 DOI: 10.1007/s00436-022-07516-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 04/04/2022] [Indexed: 11/29/2022]
Abstract
Investigating parameters influencing natural infections with Trypanosoma cruzi via the skin, the diameters of mouthparts of different stages of triatomines vectors were measured to determine the size of the channel accessible for T. cruzi during cutaneous infection. The mean diameters of the skin-penetrating mandibles of first to fifth instar nymphs of the vector Triatoma infestans increased from 18 to 65 µm. The mean diameter in fourth instar nymphs of Dipetalogaster maxima was 86 µm. Different numbers of isolated vector-derived metacyclic trypomastigotes (10–10,000) were injected intradermally into mice. Prepatent periods, parasitemia and mortality rates were compared with those of mice obtaining 10,000 metacyclic trypomastigotes that are usually present in the first drop of faeces onto the feeding wounds of fifth and fourth instar nymphs of T. infestans and D. maxima, respectively. After injection of 50–10,000 T. cruzi, in all 42 mice the infection developed. An injection of 10 parasites induced an infection in 8 out of 15 mice. With increasing doses of parasites, prepatent periods tended to decrease. The level of parasitemia was higher after injection of the lowest dose. Except for one mouse all infected mice died. After placement of 10,000 metacyclic trypomastigotes onto the feeding wound of fifth or fourth instar nymphs of T. infestans and D. maxima, respectively, the infection rates of the groups, prepatent periods and the levels of parasitemia of T. cruzi in mice indicated that about 10–1,000 metacyclic trypomastigotes entered the skin via this route. For the first time, the present data emphasise the risk of an infection by infectious excreta of triatomines deposited near the feeding wound and the low number of invading parasites.
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Affiliation(s)
- Barbara Waldeck
- Zoology-Parasitology, Ruhr University, 44780, Bochum, Germany
| | - Günter A Schaub
- Zoology-Parasitology, Ruhr University, 44780, Bochum, Germany.
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de Souza Marques F, Duarte THC, Xavier VF, Ferraz AT, das Mercês AC, Silva TVC, Mendes LC, da Fonseca Medeiros L, Perin L, Mathias FAS, da Silva Fonseca K, Nogueira-Paiva NC, Carneiro CM, de Abreu Vieira PM. Different infective forms trigger distinct lesions in the colon during experimental Chagas disease. Parasitol Res 2021; 120:3475-3486. [PMID: 34476583 DOI: 10.1007/s00436-021-07236-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Accepted: 06/25/2021] [Indexed: 11/25/2022]
Abstract
With the control of vectorial transmission of Chagas disease caused by metacyclic trypomastigotes (MT) in endemic countries, other pathways of infection have become important. The infection caused by blood trypomastigotes (BT) is relevant in places where the blood transfusion and organ transplantation are poorly controlled. This study aimed to evaluate immunopathogenic parameters in the colon during the acute and chronic phases of experimental infection in Swiss mice infected with BT or MT forms of VL-10 strain of Trypanosoma cruzi. We have found that animals infected with MT forms presented lower survival rate, and higher tissue parasitism in the acute phase of the disease, which may be associated with the exacerbated activation of the immune system with the production of pro-inflammatory cytokines even in the chronic phase of infection. Taken together, these results can also be associated to the maintenance of the inflammatory process in chronic phase and an earlier denervation of myenteric plexus in colon. These findings emphasized the importance of the inoculum source and the strain, once different forms of different strains seem to promote distinct diseases.
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Affiliation(s)
- Flávia de Souza Marques
- Laboratory of Morphopathology, Department of Biological Sciences, Nucleus of Biological Sciences Research, Institute of Exact and Biological Sciences, Federal University of Ouro Preto, Ouro Preto, Minas Gerais, Brazil
| | - Thays Helena Chaves Duarte
- Laboratory of Morphopathology, Department of Biological Sciences, Nucleus of Biological Sciences Research, Institute of Exact and Biological Sciences, Federal University of Ouro Preto, Ouro Preto, Minas Gerais, Brazil
| | - Viviane Flores Xavier
- Laboratory of Morphopathology, Department of Biological Sciences, Nucleus of Biological Sciences Research, Institute of Exact and Biological Sciences, Federal University of Ouro Preto, Ouro Preto, Minas Gerais, Brazil
| | - Aline Tonhela Ferraz
- Laboratory of Morphopathology, Department of Biological Sciences, Nucleus of Biological Sciences Research, Institute of Exact and Biological Sciences, Federal University of Ouro Preto, Ouro Preto, Minas Gerais, Brazil
| | - Aline Coelho das Mercês
- Laboratory of Morphopathology, Department of Biological Sciences, Nucleus of Biological Sciences Research, Institute of Exact and Biological Sciences, Federal University of Ouro Preto, Ouro Preto, Minas Gerais, Brazil
| | - Thaís Vieira Carvalho Silva
- Laboratory of Morphopathology, Department of Biological Sciences, Nucleus of Biological Sciences Research, Institute of Exact and Biological Sciences, Federal University of Ouro Preto, Ouro Preto, Minas Gerais, Brazil
| | - Lívia Carvalho Mendes
- Laboratory of Immunopathology, Nucleus of Biological Sciences Research, Institute of Exact and Biological Sciences, Federal University of Ouro Preto, Ouro Preto, Minas Gerais, Brazil
| | - Luciana da Fonseca Medeiros
- Laboratory of Immunopathology, Nucleus of Biological Sciences Research, Institute of Exact and Biological Sciences, Federal University of Ouro Preto, Ouro Preto, Minas Gerais, Brazil
| | - Luísa Perin
- Laboratory of Immunopathology, Nucleus of Biological Sciences Research, Institute of Exact and Biological Sciences, Federal University of Ouro Preto, Ouro Preto, Minas Gerais, Brazil
| | - Fernando Augusto Siqueira Mathias
- Laboratory of Immunopathology, Nucleus of Biological Sciences Research, Institute of Exact and Biological Sciences, Federal University of Ouro Preto, Ouro Preto, Minas Gerais, Brazil
| | - Kátia da Silva Fonseca
- Laboratory of Immunopathology, Nucleus of Biological Sciences Research, Institute of Exact and Biological Sciences, Federal University of Ouro Preto, Ouro Preto, Minas Gerais, Brazil
| | - Nivia Carolina Nogueira-Paiva
- Laboratory of Immunopathology, Nucleus of Biological Sciences Research, Institute of Exact and Biological Sciences, Federal University of Ouro Preto, Ouro Preto, Minas Gerais, Brazil
| | - Cláudia Martins Carneiro
- Laboratory of Immunopathology, Nucleus of Biological Sciences Research, Institute of Exact and Biological Sciences, Federal University of Ouro Preto, Ouro Preto, Minas Gerais, Brazil.,Department of Clinical Analysis, School of Pharmacy, Federal University of Ouro Preto, Ouro Preto, Minas Gerais, Brazil
| | - Paula Melo de Abreu Vieira
- Laboratory of Morphopathology, Department of Biological Sciences, Nucleus of Biological Sciences Research, Institute of Exact and Biological Sciences, Federal University of Ouro Preto, Ouro Preto, Minas Gerais, Brazil.
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Cruz-Saavedra L, Vallejo GA, Guhl F, Ramírez JD. Transcriptomic changes across the life cycle of Trypanosoma cruzi II. PeerJ 2020; 8:e8947. [PMID: 32461822 PMCID: PMC7231504 DOI: 10.7717/peerj.8947] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Accepted: 03/19/2020] [Indexed: 12/15/2022] Open
Abstract
Trypanosoma cruzi is a flagellated protozoan that causes Chagas disease; it presents a complex life cycle comprising four morphological stages: epimastigote (EP), metacyclic trypomastigote (MT), cell-derived trypomastigote (CDT) and amastigote (AM). Previous transcriptomic studies on three stages (EPs, CDTs and AMs) have demonstrated differences in gene expressions among them; however, to the best of our knowledge, no studies have reported on gene expressions in MTs. Therefore, the present study compared differentially expressed genes (DEGs), and signaling pathway reconstruction in EPs, MTs, AMs and CDTs. The results revealed differences in gene expressions in the stages evaluated; these differences were greater between MTs and AMs-PTs. The signaling pathway that presented the highest number of DEGs in all the stages was associated with ribosomes protein profiles, whereas the other related pathways activated were processes related to energy metabolism from glucose, amino acid metabolism, or RNA regulation. However, the role of autophagy in the entire life cycle of T. cruzi and the presence of processes such as meiosis and homologous recombination in MTs (where the expressions of SPO11 and Rad51 plays a role) are crucial. These findings represent an important step towards the full understanding of the molecular basis during the life cycle of T. cruzi.
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Affiliation(s)
- Lissa Cruz-Saavedra
- Grupo de Investigaciones Microbiológicas-UR (GIMUR), Departamento de Biología, Facultad de Ciencias Naturales, Universidad del Rosario, Bogota, Colombia
| | - Gustavo A Vallejo
- Laboratorio de Investigación en Parasitología Tropical, Facultad de Ciencias, Universidad del Tolima, Ibagué, Colombia
| | - Felipe Guhl
- Centro de Investigaciones en Microbiología y Parasitología Tropical (CIMPAT), Facultad de Ciencias, Universidad de Los Andes, Bogota, Colombia
| | - Juan David Ramírez
- Grupo de Investigaciones Microbiológicas-UR (GIMUR), Departamento de Biología, Facultad de Ciencias Naturales, Universidad del Rosario, Bogota, Colombia
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Cruz-Saavedra L, Muñoz M, Patiño LH, Vallejo GA, Guhl F, Ramírez JD. Slight temperature changes cause rapid transcriptomic responses in Trypanosoma cruzi metacyclic trypomastigotes. Parasit Vectors 2020; 13:255. [PMID: 32410662 PMCID: PMC7226949 DOI: 10.1186/s13071-020-04125-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Accepted: 05/08/2020] [Indexed: 02/06/2023] Open
Abstract
Background Severe changes in temperature can affect the behavior and ecology of some infectious agents. Trypanosoma cruzi is a protozoan that causes Chagas disease. This parasite has high genetic variability and can be divided into six discrete typing units (DTUs). Trypanosoma cruzi also has a complex life-cycle, which includes the process of metacyclogenesis when non-infective epimastigote forms are differentiated into infective metacyclic trypomastigotes (MT). Studies in triatomines have shown that changes in temperature also affect the number and viability of MT. Methods The objective of this study was to evaluate how temperature affects the transcriptional profiles of T. cruzi I and II (TcI and TcII) MT by exposing parasites to two temperatures (27 °C and 28 °C) and comparing those to normal culture conditions at 26 °C. Subsequently, RNA-seq was conducted and differentially expressed genes were quantified and associated to metabolic pathways. Results A statistically significant difference was observed in the number of MT between the temperatures evaluated and the control, TcII DTU was not strongly affected to exposure to high temperatures compared to TcI. Similar results were found when we analyzed gene expression in this DTU, with the greatest number of differentially expressed genes being observed at 28 °C, which could indicate a dysregulation of different signaling pathways under this temperature. Chromosome analysis indicated that chromosome 1 harbored the highest number of changes for both DTUs for all thermal treatments. Finally, gene ontology (GO) analyses showed a decrease in the coding RNAs involved in the regulation of processes related to the metabolism of lipids and carbohydrates, the evasion of oxidative stress, and proteolysis and phosphorylation processes, and a decrease in RNAs coding to ribosomal proteins in TcI and TcII, along with an increase in the expression of surface metalloprotease GP63 in TcII. Conclusions Slight temperature shifts lead to increased cell death of metacyclic trypomastigotes because of the deregulation of gene expression of different processes essential for the TcI and TcII DTUs of T. cruzi.![]()
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Affiliation(s)
- Lissa Cruz-Saavedra
- Grupo de Investigaciones Microbiológicas-UR (GIMUR), Departamento de Biología, Facultad de Ciencias Naturales, Universidad del Rosario, Bogotá, Colombia
| | - Marina Muñoz
- Grupo de Investigaciones Microbiológicas-UR (GIMUR), Departamento de Biología, Facultad de Ciencias Naturales, Universidad del Rosario, Bogotá, Colombia
| | - Luz Helena Patiño
- Grupo de Investigaciones Microbiológicas-UR (GIMUR), Departamento de Biología, Facultad de Ciencias Naturales, Universidad del Rosario, Bogotá, Colombia
| | - Gustavo A Vallejo
- Laboratorio de Investigaciones en Parasitología Tropical, Facultad de Ciencias, Universidad del Tolima, Ibagué, Colombia
| | - Felipe Guhl
- Centro de Investigaciones en Microbiología y Parasitología Tropical (CIMPAT), Facultad de Ciencias, Universidad de Los Andes, Bogotá, Colombia
| | - Juan David Ramírez
- Grupo de Investigaciones Microbiológicas-UR (GIMUR), Departamento de Biología, Facultad de Ciencias Naturales, Universidad del Rosario, Bogotá, Colombia.
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Cruz-Saavedra L, Muñoz M, León C, Patarroyo MA, Arevalo G, Pavia P, Vallejo G, Carranza JC, Ramírez JD. Purification of Trypanosoma cruzi metacyclic trypomastigotes by ion exchange chromatography in sepharose-DEAE, a novel methodology for host-pathogen interaction studies. J Microbiol Methods 2017; 142:27-32. [PMID: 28865682 DOI: 10.1016/j.mimet.2017.08.021] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Revised: 08/24/2017] [Accepted: 08/24/2017] [Indexed: 01/25/2023]
Abstract
Metacyclic trypomastigotes are essential for the understanding of the biology of Trypanosoma cruzi, the agent of Chagas disease. However, obtaining these biological stages in axenic medium is difficult. Techniques based on charge and density of the parasite during different stages have been implemented, without showing a high efficiency in the purification of metacyclic trypomastigotes. So far, there is no protocol implemented where sepharose-DEAE is used as a resin. Therefore, herein we tested its ability to purify metacyclic trypomastigotes in Liver Infusion Triptose (LIT) medium cultures. A simple, easy-to-execute and effective protocol based on ion exchange chromatography on Sepharose-DEAE resin for the purification of T. cruzi trypomastigotes is described. T. cruzi strains from the Discrete Typing Units (DTUs) I and II were used. The strains were harvested in LIT medium at a concentration of 1×107epimastigotes/mL. We calculated the time of trypomastigotes increment (TTI). Based on the data obtained, Ion exchange chromatography was performed with DEAE-sepharose resin. To verify the purity and viability of the trypomastigotes, a culture was carried out in LIT medium with subsequent verification with giemsa staining. To evaluate if the technique affected the infectivity of trypomastigotes, in vitro assays were performed in Vero cells and in vivo in ICR-CD1 mice. The technique allowed the purification of metacyclic trypomastigotes of other stages of T. cruzi in a percentage of 100%, a greater recovery was observed in cultures of 12days. There were differences regarding the recovery of metacyclic trypomastigotes for both DTUs, being DTU TcI the one that recovered a greater amount of these forms. The technique did not affect parasite infectivity in vitro or/and in vivo.
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Affiliation(s)
- Lissa Cruz-Saavedra
- Universidad del Rosario, Facultad de Ciencias Naturales y Matemáticas, Programa de Biología, Grupo de Investigaciones Microbiológicas-UR (GIMUR), Bogotá, Colombia
| | - Marina Muñoz
- Universidad del Rosario, Facultad de Ciencias Naturales y Matemáticas, Programa de Biología, Grupo de Investigaciones Microbiológicas-UR (GIMUR), Bogotá, Colombia
| | - Cielo León
- Universidad del Rosario, Facultad de Ciencias Naturales y Matemáticas, Programa de Biología, Grupo de Investigaciones Microbiológicas-UR (GIMUR), Bogotá, Colombia
| | - Manuel Alfonso Patarroyo
- Molecular Biology and Immunology Department, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia; Universidad del Rosadio, School of Medicine and Health Sciences, Bogotá, Colombia
| | - Gabriela Arevalo
- Molecular Biology and Immunology Department, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia; Universidad del Rosadio, School of Medicine and Health Sciences, Bogotá, Colombia
| | - Paula Pavia
- Unidad de Investigación Cientifica, Subdirección de Docencia e Investigación, Hospital Militar Central, Bogotá, Colombia
| | - Gustavo Vallejo
- Laboratorio de Investigaciones en Parasitología Tropical-LIPT, Universidad del Tolima, Ibague, Colombia
| | - Julio César Carranza
- Laboratorio de Investigaciones en Parasitología Tropical-LIPT, Universidad del Tolima, Ibague, Colombia
| | - Juan David Ramírez
- Universidad del Rosario, Facultad de Ciencias Naturales y Matemáticas, Programa de Biología, Grupo de Investigaciones Microbiológicas-UR (GIMUR), Bogotá, Colombia.
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Kariithi HM, Boeren S, Murungi EK, Vlak JM, Abd-Alla AMM. A proteomics approach reveals molecular manipulators of distinct cellular processes in the salivary glands of Glossina m. morsitans in response to Trypanosoma b. brucei infections. Parasit Vectors 2016; 9:424. [PMID: 27485005 PMCID: PMC4969678 DOI: 10.1186/s13071-016-1714-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Accepted: 07/20/2016] [Indexed: 12/28/2022] Open
Abstract
Background Glossina m. morsitans is the primary vector of the Trypanosoma brucei group, one of the causative agents of African trypanosomoses. The parasites undergo metacyclogenesis, i.e. transformation into the mammalian-infective metacyclic trypomastigote (MT) parasites, in the salivary glands (SGs) of the tsetse vector. Since the MT-parasites are largely uncultivable in vitro, information on the molecular processes that facilitate metacyclogenesis is scanty. Methods To bridge this knowledge gap, we employed tandem mass spectrometry to investigate protein expression modulations in parasitized (T. b. brucei-infected) and unparasitized SGs of G. m. morsitans. We annotated the identified proteins into gene ontologies and mapped the up- and downregulated proteins within protein-protein interaction (PPI) networks. Results We identified 361 host proteins, of which 76.6 % (n = 276) and 22.3 % (n = 81) were up- and downregulated, respectively, in parasitized SGs compared to unparasitized SGs. Whilst 32 proteins were significantly upregulated (> 10-fold), only salivary secreted adenosine was significantly downregulated. Amongst the significantly upregulated proteins, there were proteins associated with blood feeding, immunity, cellular proliferation, homeostasis, cytoskeletal traffic and regulation of protein turnover. The significantly upregulated proteins formed major hubs in the PPI network including key regulators of the Ras/MAPK and Ca2+/cAMP signaling pathways, ubiquitin-proteasome system and mitochondrial respiratory chain. Moreover, we identified 158 trypanosome-specific proteins, notable of which were proteins in the families of the GPI-anchored surface glycoproteins, kinetoplastid calpains, peroxiredoxins, retrotransposon host spot multigene and molecular chaperones. Whilst immune-related trypanosome proteins were over-represented, membrane transporters and proteins involved in translation repression (e.g. ribosomal proteins) were under-represented, potentially reminiscent of the growth-arrested MT-parasites. Conclusions Our data implicate the significantly upregulated proteins as manipulators of diverse cellular processes in response to T. b. brucei infection, potentially to prepare the MT-parasites for invasion and evasion of the mammalian host immune defences. We discuss potential strategies to exploit our findings in enhancement of trypanosome refractoriness or reduce the vector competence of the tsetse vector. Electronic supplementary material The online version of this article (doi:10.1186/s13071-016-1714-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Henry M Kariithi
- Biotechnology Research Institute, Kenya Agricultural and Livestock Research Organization, P.O Box 57811, 00200, Kaptagat Rd, Loresho, Nairobi, Kenya. .,Insect Pest Control Laboratories, Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, International Atomic Energy Agency, Wagrammer Straße 5, Vienna, Austria.
| | - Sjef Boeren
- Laboratory of Biochemistry, Wageningen University, Dreijenlaan 3, 6703, HA, Wageningen, The Netherlands
| | - Edwin K Murungi
- Department of Biochemistry and Molecular Biology, Egerton University, P.O. Box 536, 20115, Njoro, Kenya
| | - Just M Vlak
- Laboratory of Virology, Wageningen University, Droevendaalsesteeg 1, 6708, PB, Wageningen, The Netherlands
| | - Adly M M Abd-Alla
- Insect Pest Control Laboratories, Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, International Atomic Energy Agency, Wagrammer Straße 5, Vienna, Austria.
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Maeda FY, Clemente TM, Macedo S, Cortez C, Yoshida N. Host cell invasion and oral infection by Trypanosoma cruzi strains of genetic groups TcI and TcIV from chagasic patients. Parasit Vectors 2016; 9:189. [PMID: 27038796 PMCID: PMC4818890 DOI: 10.1186/s13071-016-1455-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Accepted: 03/16/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Outbreaks of acute Chagas disease by oral infection have been reported frequently over the last ten years, with higher incidence in northern South America, where Trypanosoma cruzi lineage TcI predominates, being responsible for the major cause of resurgent human disease, and a small percentage is identified as TcIV. Mechanisms of oral infection and host-cell invasion by these parasites are poorly understood. To address that question, we analyzed T. cruzi strains isolated from chagasic patients in Venezuela, Guatemala and Brazil. METHODS Trypanosoma cruzi metacyclic trypomastigotes were orally inoculated into mice. The mouse stomach collected four days later, as well as the stomach and the heart collected 30 days post-infection, were processed for histological analysis. Assays to mimic parasite migration through the gastric mucus layer were performed by counting the parasites that traversed gastric mucin-coated transwell filters. For cell invasion assays, human epithelial HeLa cells were incubated with metacyclic forms and the number of internalized parasites was counted. RESULTS All TcI and TcIV T. cruzi strains were poorly infective by the oral route. Parasites were either undetectable or were detected in small numbers in the mouse stomach four days post oral administration. Replicating parasites were found in the stomach and/or in the heart 30 days post-infection. As compared to TcI lineage, the migration capacity of TcIV parasites through the gastric mucin-coated filter was higher but lower than that exhibited by TcVI metacyclic forms previously shown to be highly infective by the oral route. Expression of pepsin-resistant gp90, the surface molecule that downregulates cell invasion, was higher in TcI than in TcIV parasites and, accordingly, the invasion capacity of TcIV metacyclic forms was higher. Gp90 molecules spontaneously released by TcI metacyclic forms inhibited the parasite entry into host cells. TcI parasites exhibited low intracellular replication rate. CONCLUSIONS Our findings indicate that the poor capacity of TcI lineage, and to a lesser degree of TcIV parasites, in invading gastric epithelium after oral infection of mice may be associated with the inefficiency of metacyclic forms, in particular of TcI parasites, to migrate through the gastric mucus layer, to invade target epithelial cells and to replicate intracellularly.
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Affiliation(s)
- Fernando Yukio Maeda
- Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Tatiana Mordente Clemente
- Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Silene Macedo
- Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Cristian Cortez
- Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Nobuko Yoshida
- Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo, São Paulo, Brazil.
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