1
|
Machado FS, Tyler KM, Brant F, Esper L, Teixeira MM, Tanowitz HB. Pathogenesis of Chagas disease: time to move on. Front Biosci (Elite Ed) 2012; 4:1743-58. [PMID: 22201990 DOI: 10.2741/495] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Trypanosoma cruzi is the etiologic agent of Chagas disease. The contributions of parasite and immune system for disease pathogenesis remain unresolved and controversial. The possibility that Chagas disease was an autoimmune progression triggered by T. cruzi infection led some to question the benefit of treating chronically T. cruzi-infected persons with drugs. Furthermore, it provided the rationale for not investing in research aimed at a vaccine which might carry a risk of inducing autoimmunity or exacerbating inflammation. This viewpoint was adopted by cash-strapped health systems in the developing economies where the disease is endemic and has been repeatedly challenged by researchers and clinicians in recent years and there is now a considerable body of evidence and broad consensus that parasite persistence is requisite for pathogenesis and that antiparasitic immunity can be protective against T. cruzi pathogenesis without eliciting autoimmune pathology. Thus, treatment of chronically infected patients is likely to yield positive outcomes and efforts to understand immunity and vaccine development should be recognized as a priority area of research for Chagas disease.
Collapse
Affiliation(s)
- Fabiana S Machado
- Department of Biochemistry and Immunology, Institute of Biological Sciences, Belo Horizonte, Brazil
| | | | | | | | | | | |
Collapse
|
2
|
de Araújo FF, Vitelli-Avelar DM, Teixeira-Carvalho A, Renato Zuquim Antas P, Assis Silva Gomes J, Sathler-Avelar R, Otávio Costa Rocha M, Elói-Santos SM, Pinho RT, Correa-Oliveira R, Martins-Filho OA. Regulatory T cells phenotype in different clinical forms of Chagas' disease. PLoS Negl Trop Dis 2011; 5:e992. [PMID: 21655351 PMCID: PMC3104959 DOI: 10.1371/journal.pntd.0000992] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
CD25(High) CD4+ regulatory T cells (Treg cells) have been described as key players in immune regulation, preventing infection-induced immune pathology and limiting collateral tissue damage caused by vigorous anti-parasite immune response. In this review, we summarize data obtained by the investigation of Treg cells in different clinical forms of Chagas' disease. Ex vivo immunophenotyping of whole blood, as well as after stimulation with Trypanosoma cruzi antigens, demonstrated that individuals in the indeterminate (IND) clinical form of the disease have a higher frequency of Treg cells, suggesting that an expansion of those cells could be beneficial, possibly by limiting strong cytotoxic activity and tissue damage. Additional analysis demonstrated an activated status of Treg cells based on low expression of CD62L and high expression of CD40L, CD69, and CD54 by cells from all chagasic patients after T. cruzi antigenic stimulation. Moreover, there was an increase in the frequency of the population of Foxp3+ CD25(High)CD4+ cells that was also IL-10+ in the IND group, whereas in the cardiac (CARD) group, there was an increase in the percentage of Foxp3+ CD25(High) CD4+ cells that expressed CTLA-4. These data suggest that IL-10 produced by Treg cells is effective in controlling disease development in IND patients. However, in CARD patients, the same regulatory mechanism, mediated by IL-10 and CTLA-4 expression is unlikely to be sufficient to control the progression of the disease. These data suggest that Treg cells may play an important role in controlling the immune response in Chagas' disease and the balance between regulatory and effector T cells may be important for the progression and development of the disease. Additional detailed analysis of the mechanisms on how these cells are activated and exert their function will certainly give insights for the rational design of procedure to achieve the appropriate balance between protection and pathology during parasite infections.
Collapse
Affiliation(s)
- Fernanda Fortes de Araújo
- Laboratório de Imunologia Celular e Molecular, Centro de Pesquisas René Rachou, FIOCRUZ, Belo Horizonte, Brasil
| | | | - Andréa Teixeira-Carvalho
- Laboratório de Biomarcadores de Diagnóstico e Monitoração, Centro de Pesquisas René Rachou, FIOCRUZ, Belo Horizonte, Brasil
- * E-mail:
| | | | - Juliana Assis Silva Gomes
- Laboratório de Imunologia Celular e Molecular, Centro de Pesquisas René Rachou, FIOCRUZ, Belo Horizonte, Brasil
- Laboratório de Biomarcadores de Diagnóstico e Monitoração, Centro de Pesquisas René Rachou, FIOCRUZ, Belo Horizonte, Brasil
- Laboratório de Biologia das Interações Celulares, Departamento de Morfologia, Instituto de Ciências Biológicas, UFMG, Belo Horizonte, Brasil
| | - Renato Sathler-Avelar
- Laboratório de Biomarcadores de Diagnóstico e Monitoração, Centro de Pesquisas René Rachou, FIOCRUZ, Belo Horizonte, Brasil
| | | | - Silvana Maria Elói-Santos
- Laboratório de Biomarcadores de Diagnóstico e Monitoração, Centro de Pesquisas René Rachou, FIOCRUZ, Belo Horizonte, Brasil
- Departamento de Propedêutica complementar, Faculdade de Medicina, UFMG, Belo Horizonte, Brasil
| | - Rosa Teixeira Pinho
- Laboratório de Imunologia Clínica, Instituto Oswaldo Cruz, FIOCRUZ, Rio de Janeiro, Brasil
| | - Rodrigo Correa-Oliveira
- Laboratório de Imunologia Celular e Molecular, Centro de Pesquisas René Rachou, FIOCRUZ, Belo Horizonte, Brasil
- Instituto Nacional de Ciência e Tecnologia em Doenças Tropicais, INCT-DT, Salvador, Brasil
| | - Olindo Assis Martins-Filho
- Laboratório de Biomarcadores de Diagnóstico e Monitoração, Centro de Pesquisas René Rachou, FIOCRUZ, Belo Horizonte, Brasil
| |
Collapse
|
3
|
Dutra WO, Menezes CAS, Villani FNA, da Costa GC, da Silveira ABM, Reis DD, Gollob KJ. Cellular and genetic mechanisms involved in the generation of protective and pathogenic immune responses in human Chagas disease. Mem Inst Oswaldo Cruz 2010; 104 Suppl 1:208-18. [PMID: 19753476 DOI: 10.1590/s0074-02762009000900027] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2009] [Accepted: 05/14/2009] [Indexed: 01/02/2023] Open
Abstract
Perhaps one of the most intriguing aspects of human Chagas disease is the complex network of events that underlie the generation of protective versus pathogenic immune responses during the chronic phase of the disease. While most individuals do not develop patent disease, a large percentage may develop severe forms that eventually lead to death. Although many efforts have been devoted to deciphering these mechanisms, there is still much to be learned before we can fully understand the pathogenesis of Chagas disease. It is clear that the host's immune response is decisive in this process. While characteristics of the parasite influence the immune response, it is becoming evident that the host genetic background plays a fundamental role in the establishment of pathogenic versus protective responses. The involvement of three complex organisms, host, parasite and vector, is certainly one of the key aspects that calls for multidisciplinary approaches towards the understanding of Chagas disease. We believe that now, one hundred years after the discovery of Chagas disease, it is imperative to continue with highly interactive research in order to elucidate the immune response associated with disease evolution, which will be essential in designing prophylactic or therapeutic interventions.
Collapse
Affiliation(s)
- Walderez Ornelas Dutra
- Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brasil.
| | | | | | | | | | | | | |
Collapse
|
4
|
Verçosa A, Lorena V, Carvalho C, Melo M, Cavalcanti M, Silva E, Ferreira A, Pereira V, Souza W, Gomes Y. Chagas' disease: IgG isotypes against cytoplasmic (CRA) and flagellar (FRA) recombinant repetitive antigens of Trypanosoma cruzi in chronic Chagasic patients. J Clin Lab Anal 2007; 21:271-6. [PMID: 17847109 PMCID: PMC6649189 DOI: 10.1002/jcla.20186] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
The wide range of clinical Chagas' disease manifestations, of which heart involvement is the most significant, because of its characteristics, frequency and consequences, and lack of treatment and cure, justify research in this area. Specific immunoglobulin G (IgG) antibody subclasses have been associated with human Chagas' disease. Thus, in this study, the profile of IgG subclasses against cytoplasmic (CRA) and flagellar (FRA) recombinant repetitive T. cruzi-specific antigens was correlated with cardiac (CARD, n=33), cardiodigestive (CD, n=7), and indeterminate (IND, n=20) forms of Chagas' disease by indirect enzyme-linked immunosorbent assay (ELISA). IgG subclasses were detected in almost all Chagas patients studied. Nevertheless, only specific IgG2 isotype FRA was found with a significant statistical difference in CARD patients when compared to IND patients. This result suggests the potential use of this isotype for prognostic purposes, for monitoring the progression of chronic Chagas' disease, and for predicting the risk of CARD damage. This is important information, as it could help physicians to evaluate and manage the treatment of their patients. However, a follow-up study is necessary to confirm our result.
Collapse
Affiliation(s)
- A.F.A. Verçosa
- Centro de Pesquisas Aggeu Magalhães (CPqAM)/Fiocruz, Recife‐PE, Brazil
| | - V.M.B. Lorena
- Centro de Pesquisas Aggeu Magalhães (CPqAM)/Fiocruz, Recife‐PE, Brazil
| | - C.L. Carvalho
- Centro de Pesquisas Aggeu Magalhães (CPqAM)/Fiocruz, Recife‐PE, Brazil
| | - M.F.A.D. Melo
- Centro de Pesquisas Aggeu Magalhães (CPqAM)/Fiocruz, Recife‐PE, Brazil
| | - M.G.A. Cavalcanti
- Hospital Oswaldo Cruz (HUOC)/Universidade de Pernambuco (UPE), Recife‐PE, Brazil
| | - E.D. Silva
- Bio‐Manguinhos/Fiocruz, Rio de Janeiro‐RJ, Brazil
| | | | - V.R.A. Pereira
- Centro de Pesquisas Aggeu Magalhães (CPqAM)/Fiocruz, Recife‐PE, Brazil
| | - W.V. Souza
- Centro de Pesquisas Aggeu Magalhães (CPqAM)/Fiocruz, Recife‐PE, Brazil
| | - Y.M. Gomes
- Centro de Pesquisas Aggeu Magalhães (CPqAM)/Fiocruz, Recife‐PE, Brazil
| |
Collapse
|
5
|
Pavón-Martínez N, Masso-Rojas F, López-Alcántara R, Monteón VM. Altered pattern of connectivity in Chagas disease. Ann N Y Acad Sci 2007; 1107:271-9. [PMID: 17804555 DOI: 10.1196/annals.1381.029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
It has been proposed that natural autoreactivity plays a physiological role in the immune system by connecting all these clones (Id/anti-Id) and forming a dense and highly regulated network. In the present work, we analyzed the connectivity pattern in Chagas disease. Serum samples of 20 chronic chagasic cardiopathy (CCC) patients with dilated cardiopathy, 20 infected-asymptomatic subjects (IAS), and 20 healthy seronegative controls (H) were tested. Pattern of connectivity was distinguishable from that of healthy donor and those with CCC and IAS. This suggests that there are alterations in regulatory networks, inclusive being more evident in CCC patients than in IAS.
Collapse
Affiliation(s)
- Natalia Pavón-Martínez
- Instituto Nacional Cardiología Ignacio Chávez, México DF, Juan Badiano 1, Mexico City, Mexico
| | | | | | | |
Collapse
|
6
|
Dutra WO, Rocha MOC, Teixeira MM. The clinical immunology of human Chagas disease. Trends Parasitol 2005; 21:581-7. [PMID: 16236550 DOI: 10.1016/j.pt.2005.09.007] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2005] [Revised: 08/05/2005] [Accepted: 09/28/2005] [Indexed: 10/25/2022]
Abstract
Human infection with the protozoan parasite Trypanosoma cruzi leads to Chagas disease, which affects approximately 17 million people in Latin America. A significant percentage of the infected population will develop clinical symptoms or present changes in laboratory and/or image evaluation. The existence of a large spectrum of clinical manifestations--with patients ranging from asymptomatic to severe cardiac involvement--emphasizes the need to use standardized and well-defined clinical criteria among different research groups. In this article, we carry out a systematic review of the immunology in human Chagas disease, discussing recent findings in the context of a clinical perspective.
Collapse
Affiliation(s)
- Walderez O Dutra
- Department of Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Avenida Antônio Carlos 6627, Belo Horizonte, Minas Gerais 31270-901, Brazil
| | | | | |
Collapse
|
7
|
Kerner N, Liégeard P, Levin MJ, Hontebeyrie-Joskowicz M. Trypanosoma cruzi: antibodies to a MAP-like protein in chronic Chagas' disease cross-react with mammalian cytoskeleton. Exp Parasitol 1991; 73:451-9. [PMID: 1959572 DOI: 10.1016/0014-4894(91)90069-9] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Trypanosoma cruzi lambda gt 11 library from epimastogote derived mRNA was screened with human chagasic sera or sera from chronically infected mice. Strong reactive recombinants were detected with both sera. Two recombinant clones were studied in more detail and shown to be composed of the same 114-bp repetitive sequence coding for a 38 amino acid repetition. This repetition is the same size and shares greater than 60% homology with the reported T. brucei microtubule associated protein (MAP) p320. The insert of one of these clones, K1-7 (228 bp), was subcloned into pMSgt11 and the soluble recombinant polypeptide expressed. Antibodies against the K1-7 fusion polypeptide recognized a major 110-kDa band from cytoskeleton. Anti K1-7 monospecific antibodies detected several cytoskeletal proteins from 3T3 fibroblasts and bovine brain microtubule preparations. Reciprocally, anti-MAP1b monoclonal antibodies raised against bovine brain microtubule reacted with the K1-7 polypeptide on Western blots. The protein identified by K1-7 antibodies may be one of the parasite molecules associated to molecular mimicry.
Collapse
|