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1.
PLoS Negl Trop Dis ; 14(5): e0007980, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32433643

RESUMO

Chagas disease, the clinical presentation of T. cruzi infection, is a major human health concern. While the acute phase of Chagas disease is typically asymptomatic and self-resolving, chronically infected individuals suffer numerous sequelae later in life. Cardiomyopathies in particular are the most severe consequence of chronic Chagas disease and cannot be reversed solely by parasite load reduction. To prioritize new therapeutic targets, we unbiasedly interrogated the host signaling events in heart tissues isolated from a Chagas disease mouse model using quantitative, multiplexed proteomics. We defined the host response to infection at both the proteome and phospho-proteome levels. The proteome showed an increase in the immune response and a strong repression of several mitochondrial proteins. Complementing the proteome studies, the phospho-proteomic survey found an abundance of phospho-site alterations in plasma membrane and cytoskeletal proteins. Bioinformatic analysis of kinase activity provided substantial evidence for the activation of NDRG2 and JNK/p38 kinases during Chagas disease. A significant activation of DYRK2 and AMPKA2 and the inhibition of casein family kinases were also predicted. We concluded our analyses by linking the diseased heart proteome profile to known therapeutic interventions, uncovering a potential to target mitochondrial proteins, secreted immune effectors and core kinases for the treatment of chronic Chagas disease. Together, this study provides molecular insight into host proteome and phospho-proteome responses to T. cruzi infection in the heart for the first time, highlighting pathways that can be further validated for functional contributions to disease and suitability as drug targets.


Assuntos
Cardiomiopatia Chagásica/metabolismo , Animais , Cardiomiopatia Chagásica/genética , Cardiomiopatia Chagásica/imunologia , Cardiomiopatia Chagásica/parasitologia , Feminino , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Proteoma/genética , Proteoma/metabolismo , Proteômica , Transdução de Sinais , Trypanosoma cruzi/fisiologia
2.
PLoS Pathog ; 16(4): e1008474, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32315358

RESUMO

Trypanosoma cruzi (T. cruzi) is the etiological agent of Chagas cardiomyopathy. In the present study, we investigated the role of extracellular vesicles (Ev) in shaping the macrophage (Mφ) response in progressive Chagas disease (CD). We purified T. cruzi Ev (TcEv) from axenic parasite cultures, and T. cruzi-induced Ev (TEv) from the supernatants of infected cells and plasma of acutely and chronically infected wild-type and Parp1-/- mice. Cultured (Raw 264.7) and bone-marrow Mφ responded to TcEV and TEv with a profound increase in the expression and release of TNF-α, IL-6, and IL-1ß cytokines. TEv produced by both immune (Mφ) and non-immune (muscle) cells were proinflammatory. Chemical inhibition or genetic deletion of PARP1 (a DNA repair enzyme) significantly depressed the TEv-induced transcriptional and translational activation of proinflammatory Mφ response. Oxidized DNA encapsulated by TEv was necessary for PARP1-dependent proinflammatory Mφ response. Inhibition studies suggested that DNA-sensing innate immune receptors (cGAS>>TLR9) synergized with PARP1 in signaling the NFκB activation, and inhibition of PARP1 and cGAS resulted in >80% inhibition of TEv-induced NFκB activity. Histochemical studies showed intense inflammatory infiltrate associated with profound increase in CD11b+CD68+TNF-α+ Mφ in the myocardium of CD wild-type mice. In comparison, chronically infected Parp1-/- mice exhibited low-to-moderate tissue inflammation, >80% decline in myocardial infiltration of TNF-α+ Mφ, and no change in immunoregulatory IL-10+ Mφ. We conclude that oxidized DNA released with TEv signal the PARP1-cGAS-NF-κB pathway of proinflammatory Mφ activation and worsens the chronic inflammatory pathology in CD. Small molecule antagonists of PARP1-cGAS signaling pathway would potentially be useful in reprogramming the Mφ activation and controlling the chronic inflammation in CD.


Assuntos
Doença de Chagas/metabolismo , Vesículas Extracelulares/metabolismo , Ativação de Macrófagos/imunologia , Macrófagos/imunologia , NF-kappa B/metabolismo , Nucleotidiltransferases/metabolismo , Poli(ADP-Ribose) Polimerase-1/metabolismo , Animais , Cardiomiopatia Chagásica/imunologia , Cardiomiopatia Chagásica/metabolismo , Citocinas/imunologia , Citocinas/metabolismo , Feminino , Interleucina-1beta/imunologia , Interleucina-1beta/metabolismo , Interleucina-6/imunologia , Interleucina-6/metabolismo , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Knockout , NF-kappa B/imunologia , Nucleotidiltransferases/imunologia , Poli(ADP-Ribose) Polimerase-1/imunologia , Células RAW 264.7 , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/imunologia , Trypanosoma cruzi/metabolismo , Trypanosoma cruzi/patogenicidade , Fator de Necrose Tumoral alfa/imunologia , Fator de Necrose Tumoral alfa/metabolismo
3.
J Immunol ; 204(6): 1571-1581, 2020 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-32060134

RESUMO

T cell-mediated immune response plays a crucial role in controlling Trypanosoma cruzi infection and parasite burden, but it is also involved in the clinical onset and progression of chronic Chagas' disease. Therefore, the study of T cells is central to the understanding of the immune response against the parasite and its implications for the infected organism. The complexity of the parasite-host interactions hampers the identification and characterization of T cell-activating epitopes. We approached this issue by combining in silico and in vitro methods to interrogate patients' T cells specificity. Fifty T. cruzi peptides predicted to bind a broad range of class I and II HLA molecules were selected for in vitro screening against PBMC samples from a cohort of chronic Chagas' disease patients, using IFN-γ secretion as a readout. Seven of these peptides were shown to activate this type of T cell response, and four out of these contain class I and II epitopes that, to our knowledge, are first described in this study. The remaining three contain sequences that had been previously demonstrated to induce CD8+ T cell response in Chagas' disease patients, or bind HLA-A*02:01, but are, in this study, demonstrated to engage CD4+ T cells. We also assessed the degree of differentiation of activated T cells and looked into the HLA variants that might restrict the recognition of these peptides in the context of human T. cruzi infection.


Assuntos
Antígenos de Protozoários/imunologia , Linfócitos T CD4-Positivos/imunologia , Cardiomiopatia Chagásica/imunologia , Epitopos de Linfócito T/imunologia , Trypanosoma cruzi/imunologia , Antígenos de Protozoários/metabolismo , Argentina , Linfócitos T CD4-Positivos/metabolismo , Diferenciação Celular/imunologia , Cardiomiopatia Chagásica/sangue , Cardiomiopatia Chagásica/parasitologia , Simulação por Computador , ELISPOT , Epitopos de Linfócito T/metabolismo , Feminino , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe I/metabolismo , Antígenos de Histocompatibilidade Classe II/imunologia , Antígenos de Histocompatibilidade Classe II/metabolismo , Humanos , Imunidade Celular , Memória Imunológica , Testes de Liberação de Interferon-gama , Ativação Linfocitária , Masculino , Trypanosoma cruzi/metabolismo
4.
Biochim Biophys Acta Mol Basis Dis ; 1866(5): 165658, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-31904415

RESUMO

Chagas disease is currently endemic to 21 Latin-American countries and has also become a global concern because of globalization and mass migration of chronically infected individuals. Prophylactic and therapeutic vaccination might contribute to control the infection and the pathology, as complement of other strategies such as vector control and chemotherapy. Ideal prophylactic vaccine would produce sterilizing immunity; however, a reduction of the parasite burden would prevent progression from Trypanosoma cruzi infection to Chagas disease. A therapeutic vaccine for Chagas disease may improve or even replace the treatment with current drugs which have several side effects and require long term treatment that frequently leads to therapeutic withdrawal. Here, we will review some aspects about sub-unit vaccines, the rationale behind the selection of the immunogen, the role of adjuvants, the advantages and limitations of DNA-based vaccines and the idea of therapeutic vaccines. One of the main limitations to advance vaccine development against Chagas disease is the high number of variables that must be considered and the lack of uniform criteria among research laboratories. To make possible comparisons, much of this review will be focused on experiments that kept many variables constant including antigen mass/doses, type of eukaryotic plasmid, DNA-delivery system, mice strain and sex, lethal and sublethal model of infection, and similar immunogenicity and efficacy assessments.


Assuntos
Antígenos de Protozoários/imunologia , Cardiomiopatia Chagásica/prevenção & controle , Vacinas Protozoárias/imunologia , Projetos de Pesquisa , Trypanosoma cruzi/imunologia , Animais , Cardiomiopatia Chagásica/imunologia , Cardiomiopatia Chagásica/parasitologia , Modelos Animais de Doenças , Feminino , Humanos , Imunogenicidade da Vacina , Masculino , Camundongos , Vacinas Protozoárias/administração & dosagem , Fatores Sexuais , Vacinas de Subunidades/administração & dosagem , Vacinas de Subunidades/imunologia
5.
Acta Trop ; 202: 105242, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31669531

RESUMO

The lack of useful tools for detection the impact of treatment during the follow-up of chronic Chagas disease treated patients difficult the adequate care to the affected population. The objective of this study was to evaluate the functional response of CD8+ T lymphocyte population, critical for the control of Trypanosoma cruzi infection, as a possible cellular biomarker of treated Chagas disease patients. Thus, we analyzed the antigen-specific CD8+ T-cell response before and after benznidazole treatment in asymptomatic (indeterminate) and cardiac chronic Chagas disease patients. A marked dysfunctional process of the CD8+ T cell population was found in patients with an advanced pathology. Thus, the cardiac patients have a higher co-expression of inhibitory receptors and a lower antigen-specific multifunctional capacity compared with that of asymptomatic patients. Remarkably, benznidazole treatment partially reverses this functional exhaustion process of CD8+ T cells in both asymptomatic and cardiac Chagas disease patients. Thus, the co-expression of inhibitory molecules tends to be reduced after benznidazole treatment, mainly in asymptomatic patients, finding a significant drop in the expression of inhibitory receptors such as PD-1 and 2B4. In addition, the multifunctional antigen-specific response of CD8+ T cells is enhanced after treatment in chronic patients. An increase in the subset of cells with cytotoxic capacity and production of the IFN-γ cytokine was also observed in both treated asymptomatic and cardiac chronic Chagas disease patients. The results derived from this study show the improvement of the functional capacity of CD8+ T cells after treatment which could be have a positive effect on parasitic control. In addition, the phenotypic and functional profile of the CD8+ T cells described could serve as a tool for monitoring the impact of benznidazole treatment.


Assuntos
Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/metabolismo , Doença de Chagas , Receptores Coestimuladores e Inibidores de Linfócitos T/metabolismo , Nitroimidazóis/farmacologia , Tripanossomicidas/farmacologia , Trypanosoma cruzi , Biomarcadores/sangue , Linfócitos T CD8-Positivos/imunologia , Cardiomiopatia Chagásica/tratamento farmacológico , Cardiomiopatia Chagásica/imunologia , Doença de Chagas/tratamento farmacológico , Doença de Chagas/imunologia , Doença Crônica , Citocinas/sangue , Humanos , Nitroimidazóis/uso terapêutico , Receptor de Morte Celular Programada 1/sangue , Família de Moléculas de Sinalização da Ativação Linfocitária/sangue , Tripanossomicidas/uso terapêutico
6.
Rev Soc Bras Med Trop ; 52: e20190386, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31800924

RESUMO

INTRODUCTION: Chronic chagasic cardiopathy (CCC) is essentially a dilated cardiomyopathy in which a subacute, but constant chronic inflammatory process causes progressive destruction of the heart tissue. The action of proinflammatory cytokines, such as tumor necrosis factor alpha (TNF-α), interferon gamma (IFN-γ), and anti-inflammatory cytokines, like interleukin IL-10 and IL-17, plays a fundamental role in the immunopathogenesis and evolution of disease. Early anti-congestive therapy, aimed at changing the morbidity and mortality rate, has been shown to reduce disease progression and to alter patients' immune response pattern. METHODS: This cross-sectional study aimed to evaluate the profile of Th1 and Th17 cytokines and IL-17, TNF-α, and IFN-γ expressions in different stages of CCC. Forty patients affected by chronic Chagas disease were divided into different groups according to the stage of the pathology. In agreement with the Brazilian consensus on Chagas disease, patients were classified as presenting an undetermined form, a cardiac form and a digestive form. Serum IFN-γ, TNF-α, IL-10, and IL-17 were evaluated. RESULTS: Lower serum IFN-γ concentrations were detected in patients receiving angiotensin-converting enzyme inhibitors (p = 0.0182), but not in those using angiotensin receptor blockers (p = 0.0783). Patients using amiodarone and aldosterone antagonist presented higher serum TNF-α concentrations (p = 0.0106 and 0.0187, respectively). IL-10 and IL-17 levels did not differ between the study groups (p = 0.7273 and p = 0.6697, respectively). CONCLUSIONS: These results suggest that the cytokine profile and disease progression are altered by anti-congestive medications commonly prescribed for CCC.


Assuntos
Cardiomiopatia Chagásica/imunologia , Citocinas/sangue , Adulto , Idoso , Cardiomiopatia Chagásica/sangue , Cardiomiopatia Chagásica/tratamento farmacológico , Doença Crônica , Estudos Transversais , Citocinas/imunologia , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
7.
PLoS Negl Trop Dis ; 13(7): e0007597, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31356587

RESUMO

CD8+ T lymphocytes play an important role in controlling infections by intracellular pathogens. Chemokines and their receptors are crucial for the migration of CD8+ T-lymphocytes, which are the main IFNγ producers and cytotoxic effectors cells. Although the participation of chemokine ligands and receptors has been largely explored in viral infection, much less is known in infection by Trypanosoma cruzi, the causative agent of Chagas disease. After T. cruzi infection, CXCR3 chemokine receptor is highly expressed on the surface of CD8+ T-lymphocytes. Here, we hypothesized that CXCR3 is a key molecule for migration of parasite-specific CD8+ T-cells towards infected tissues, where they may play their effector activities. Using a model of induction of resistance to highly susceptible A/Sn mice using an ASP2-carrying DNA/adenovirus prime-boost strategy, we showed that CXCR3 expression was upregulated on CD8+ T-cells, which selectively migrated towards its ligands CXCL9 and CXCL10. Anti-CXCR3 administration reversed the vaccine-induced resistance to T. cruzi infection in a way associated with hampered cytotoxic activity and increased proapoptotic markers on the H2KK-restricted TEWETGQI-specific CD8+ T-cells. Furthermore, CXCR3 receptor critically guided TEWETGQI-specific effector CD8+ T-cells to the infected heart tissue that express CXCL9 and CXCL10. Overall, our study pointed CXCR3 and its ligands as key molecules to drive T. cruzi-specific effector CD8+ T-cells into the infected heart tissue. The unveiling of the process driving cell migration and colonization of infected tissues by pathogen-specific effector T-cells is a crucial requirement to the development of vaccine strategies.


Assuntos
Vacinas contra Adenovirus/imunologia , Linfócitos T CD8-Positivos/imunologia , Cardiomiopatia Chagásica/imunologia , Quimiotaxia de Leucócito , Miocárdio/metabolismo , Receptores CXCR3/metabolismo , Trypanosoma cruzi/imunologia , Animais , Apoptose , Cardiomiopatia Chagásica/parasitologia , Cardiomiopatia Chagásica/prevenção & controle , Feminino , Coração/parasitologia , Ligantes , Camundongos , Camundongos Endogâmicos C57BL , Miocárdio/imunologia , Receptores CCR2/metabolismo , Baço/imunologia , Regulação para Cima , Vacinas de DNA/imunologia
8.
Front Immunol ; 10: 1257, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31244833

RESUMO

Chronic Chagas disease cardiomyopathy (CCC) is a major cause of heart disease in Latin America and treatment for this condition is unsatisfactory. Here we investigated the effects of BA5, an amide semi-synthetic derivative betulinic acid, in a model of CCC. Mice chronically infected with T. cruzi were treated orally with BA5 (10 or 1 mg/Kg), three times per week, for 2 months. BA5 treatment decreased inflammation and fibrosis in heart sections but did not improve exercise capacity or ameliorate cardiac electric disturbances in infected mice. Serum concentrations of TNF-α, IFN-γ, and IL-1ß, as well as cardiac gene expression of pro-inflammatory mediators, were reduced after BA5 treatment. In contrast, a significant increase in the anti-inflammatory cytokine IL-10 concentration was observed in BA5-treated mice in both tested doses compared to vehicle-treated mice. Moreover, polarization to anti-inflammatory/M2 macrophage phenotype was evidenced by a decrease in the expression of NOS2 and proinflammatory cytokines and the increase in M2 markers, such as Arg1 and CHI3 in mice treated with BA5. In conclusion, BA5 had a potent anti-inflammatory activity on a model of parasite-driven heart disease related to IL-10 production and a switch from M1 to M2 subset of macrophages.


Assuntos
Anti-Inflamatórios/farmacologia , Cardiomiopatia Chagásica/tratamento farmacológico , Interleucina-10/imunologia , Macrófagos/imunologia , Triterpenos/farmacologia , Trypanosoma cruzi/imunologia , Animais , Cardiomiopatia Chagásica/imunologia , Cardiomiopatia Chagásica/patologia , Doença Crônica , Modelos Animais de Doenças , Fibrose , Inflamação/tratamento farmacológico , Inflamação/imunologia , Inflamação/patologia , Macrófagos/patologia , Camundongos , Triterpenos Pentacíclicos
9.
PLoS Negl Trop Dis ; 13(5): e0007413, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31145733

RESUMO

Chagas disease, caused by the parasite Trypanosoma cruzi, develops into chronic Chagas' cardiomyopathy in ~30% of infected individuals, characterized by conduction disorders, arrhythmias, heart failure, and even sudden cardiac death. Current anti-parasitic treatments are plagued by significant side effects and poor efficacy in the chronic phase of disease; thus, there is a pressing need for new treatment options. A therapeutic vaccine could bolster the protective TH1-mediated immune response, thereby slowing or halting the progression of chronic Chagas' cardiomyopathy. Prior work in mice has demonstrated therapeutic efficacy of a Tc24 recombinant protein vaccine in the acute phase of Chagas disease. However, it is anticipated that humans will be vaccinated therapeutically when in the chronic phase of disease. This study investigates the therapeutic efficacy of a vaccine prototype containing recombinant protein Tc24, formulated with an emulsion containing the Toll-like receptor 4 agonist E6020 as an immunomodulatory adjuvant in a mouse model of chronic T. cruzi infection. Among outbred ICR mice vaccinated during chronic T. cruzi infection, there is a significant increase in the number of animals with undetectable systemic parasitemia (60% of vaccinated mice compared to 0% in the sham vaccine control group), and a two-fold reduction in cardiac fibrosis over the control group. The vaccinated mice produce a robust protective TH1-biased immune response to the vaccine, as demonstrated by a significant increase in antigen-specific IFNγ-production, the number of antigen-specific IFNγ-producing cells, and IgG2a antibody titers. Importantly, therapeutic vaccination significantly reduced cardiac fibrosis in chronically infected mice. This is a first study demonstrating therapeutic efficacy of the prototype Tc24 recombinant protein and E6020 stable emulsion vaccine against cardiac fibrosis in a mouse model of chronic T. cruzi infection.


Assuntos
Anticorpos Antiprotozoários/imunologia , Cardiomiopatia Chagásica/imunologia , Vacinas Protozoárias/administração & dosagem , Animais , Cardiomiopatia Chagásica/parasitologia , Cardiomiopatia Chagásica/patologia , Cardiomiopatia Chagásica/prevenção & controle , Modelos Animais de Doenças , Feminino , Fibrose , Humanos , Interferon gama/genética , Interferon gama/imunologia , Camundongos , Camundongos Endogâmicos ICR , Miocárdio/patologia , Parasitemia/imunologia , Parasitemia/parasitologia , Parasitemia/patologia , Parasitemia/prevenção & controle , Vacinas Protozoárias/imunologia , Células Th1/imunologia , Trypanosoma cruzi/imunologia , Trypanosoma cruzi/fisiologia , Vacinação
10.
Front Immunol ; 10: 800, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31057540

RESUMO

Background: Chagas cardiomyopathy is the main fibrosing myocarditis among known heart diseases. Development of cardiomyopathy has been related to extracellular matrix (ECM) remodeling, which are controlled by matrix metalloproteinases (MMPs) and cytokines, especially interleukin (IL)-1ß. The convertion of 31KDa inactive precursor, the proIL-1ß in 17KDa active IL-1ß peptide, is controlled by caspase-1-dependent pathway, associated with inflammasomes. Other caspase-1 independent mechanisms mediated by proteases, especially as MMPs, have already been described. Methods: We evaluated IL-1ß activation pathways in neutrophils and monocyte subsets from patients with different clinical forms of Chagas disease after T. cruzi antigen stimulation by multiparameter flow cytometry. Results: Our data demonstrated that Chagas patients with the indeterminate clinical form (IND) showed increased levels of IL-1ß post-stimulation as well as increased expression of MMP-2, NLRP3, and CASP1, which are associated with the classical caspase-1-dependent pathway. Conversely, patients with the cardiac clinical form (CARD) showed increased IL-1ß after stimulation associated with MMP-9 and alternative caspase-1-independent pathway. Conclusions: We suggest some distinct molecular mechanisms for production of IL-1ß in innate immune cells from patients with different clinical forms of Chagas disease. MMP-2 and MMP-9 gelatinases are associated with distinct disease outcomes and IL-1ß production.


Assuntos
Cardiomiopatia Chagásica/imunologia , Doença de Chagas/imunologia , Imunidade Inata/imunologia , Interleucina-1beta/imunologia , Adulto , Idoso , Caspase 1/imunologia , Citocinas/imunologia , Feminino , Humanos , Inflamassomos/imunologia , Masculino , Metaloproteinase 2 da Matriz/imunologia , Metaloproteinase 9 da Matriz/imunologia , Pessoa de Meia-Idade , Monócitos/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Neutrófilos/imunologia , Trypanosoma cruzi/imunologia
11.
Infect Immun ; 87(6)2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30936158

RESUMO

In chronic Trypanosoma cruzi infection, the cause of Chagas disease, life-threatening inflammatory diseases develop over time in the heart, esophagus, and colon of some patients. C57BL/6 mice infected with the myotropic Colombiana strain of T. cruzi model many of the immunological and parasitological features of human infection but succumb to chronic paralyzing myositis and skeletal muscle vasculitis, not cardiomyopathy or gastrointestinal disease. Here we show that T cell depletion in the chronic phase of this model increased tissue parasitism to acute-phase levels and induced neutrophilic skeletal muscle inflammation. Conversely, after daily treatment with the trypanocide benznidazole for 8 weeks during the chronic phase, viable parasites were no longer detectable, myositis completely resolved, vasculitis was ∼80% reduced, fibrosis was reduced, and myofiber morphology normalized. After the drug was discontinued, parasitism rebounded, and immunopathology recurred. The parasite load was statistically strongly correlated with the severity of inflammation. Thus, both T cell immunity and trypanocidal pharmacotherapy suppress to very low levels, but do not cure, T. cruzi infection, which is necessary and possibly sufficient to induce crippling chronic skeletal muscle myositis and vasculitis in the model.


Assuntos
Cardiomiopatia Chagásica/parasitologia , Músculo Esquelético/parasitologia , Miosite/parasitologia , Trypanosoma cruzi/fisiologia , Vasculite/parasitologia , Animais , Cardiomiopatia Chagásica/imunologia , Modelos Animais de Doenças , Humanos , Imunidade , Camundongos , Camundongos Endogâmicos C57BL , Miosite/imunologia , Linfócitos T/imunologia , Vasculite/imunologia
12.
Hum Immunol ; 80(7): 517-522, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30853363

RESUMO

INTRODUCTION: Chagas disease, caused by the protozoan Trypanosoma cruzi (T. cruzi), is the fourth most important tropical disease, which affects approximately 7 million people worldwide. The mechanisms involved in the development of this disease are not completely well understood. An important protective role of regulatory T cells (Treg) in Chagas disease has been observed; however, the specific mechanisms remain unclear. We evaluated apoptosis as a possible mechanism mediated by Treg cells (CD4+CD25HighFOXP3+) to orchestrate the immune response in chronic Chagas disease. METHODS AND RESULTS: Patients with Chagas disease were grouped as the indeterminate (IND; asymptomatic patients with Chagas disease; n = 10) and dilated cardiomyopathy (CARD; n = 10). Healthy T. cruzi-negative individuals (NI; n = 10) were included as a control group. In order to evaluate the apoptotic cell profile, the expression of PD1, PD1L, CD39, CD95, CD95L molecules were investigated. We also evaluated the proportion of CD14+ cells expressing caspase 3. The IND group presented a substantially higher expression of CD39 by Treg cells as compared to the CARD group. On the other hand, the CARD group showed higher expression of PD-1 by Treg cells than both NI and IND groups. Significant positive correlations were observed between Treg CD95L+ cells and CD14 cells expressing caspase 3 as well as between Treg CD39 cells and CD14+ Caspase3+ cells in the IND group. CONCLUSION: Our data indicate that the expressions of different molecules that induce apoptosis are associated with suppressive mechanisms mediated by Treg cells and suggest a possible role for PD1 and PDL1 molecules in the morbidity of chronic Chagas disease.


Assuntos
Antígeno B7-H1/metabolismo , Cardiomiopatia Dilatada/sangue , Cardiomiopatia Chagásica/imunologia , Receptor de Morte Celular Programada 1/metabolismo , Linfócitos T Reguladores/imunologia , Trypanosoma cruzi/imunologia , Adulto , Idoso , Antígenos de Protozoários/imunologia , Apoptose/imunologia , Apirase/metabolismo , Antígenos CD4/metabolismo , Feminino , Fatores de Transcrição Forkhead/metabolismo , Humanos , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Masculino , Pessoa de Meia-Idade , Testes Sorológicos
13.
J Proteomics ; 194: 179-190, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30503829

RESUMO

Chagas disease, caused by the protozoan Trypanosoma cruzi, affects millions of people worldwide, especially in Latin America. Approximately 30% of the cases evolve to the chronic symptomatic stage due to cardiac and/or digestive damage, generally accompanied by nervous system impairment. Given the higher frequency and severity of clinical manifestations related to cardiac tissue lesion, the goal of this study was the identification of proteins associated with the disease progression towards its cardiac form. Thus, T. cruzi bloodstream trypomastigotes proteins were submitted to immunoprecipitation using antibodies from patients with the asymptomatic or cardiac (stages B1 and C) forms of the disease and from healthy donors as control. Immunoreactive proteins were identified and quantified based on mass spectrometry analysis and shifts in the recognition profile were further evaluated. Compared to asymptomatic samples, IgG from stage C patients predominantly detected the I/6 autoantigen, whereas IgG from B1 patients resulted in higher yield of dihydrolipoamide acetyltransferase precursor, calpain cysteine peptidase, and two variants of CAP5.5. In this work, CAP5.5 recognition by serum immunoglobulin from patients with early cardiomyopathy generated a 23-fold abundance variation when compared to samples from asymptomatic patients, highlighting the participation of this protein in cardiac form progression of the disease. SIGNIFICANCE: While T. cruzi has become the major cause of infectious cardiomyopathy in Latin America, research groups have been struggling to find alternative treatment, vaccine candidates, and improved diagnostic tests. In addition, the absence of adequate biomarkers to assess cure and progression of disease is a major setback for clinical trials and patients monitoring. Therefore, our findings may contribute to a better understanding of T. cruzi pathogenesis and evaluation of suitable candidates for vaccine and diagnostic tests, besides the clinical applicability of the potential biomarkers for patient follow-up and prognosis. Finally, the identification of T. cruzi proteins recognized by IgG from healthy donors may contribute for the understanding and discovery of epitope conservation among a broad range of pathogens.


Assuntos
Calpaína , Cardiomiopatia Chagásica , Proteínas de Protozoários , Trypanosoma cruzi , Anticorpos Antiprotozoários/sangue , Anticorpos Antiprotozoários/imunologia , Calpaína/sangue , Calpaína/imunologia , Cardiomiopatia Chagásica/sangue , Cardiomiopatia Chagásica/imunologia , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Masculino , Proteínas de Protozoários/sangue , Proteínas de Protozoários/imunologia , Trypanosoma cruzi/enzimologia , Trypanosoma cruzi/imunologia
14.
Annu Rev Pathol ; 14: 421-447, 2019 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-30355152

RESUMO

Chagas heart disease is an inflammatory cardiomyopathy that develops in approximately one-third of people infected with the protozoan parasite Trypanosoma cruzi. One way T. cruzi is transmitted to people is through contact with infected kissing bugs, which are found in much of the Western Hemisphere, including in vast areas of the United States. The epidemiology of T. cruzi and Chagas heart disease and the varied mechanisms leading to myocyte destruction, mononuclear cell infiltration, fibrosis, and edema in the heart have been extensively studied by hundreds of scientists for more than 100 years. Despite this wealth of knowledge, it is still impossible to predict what will happen in an individual infected with T. cruzi because of the tremendous variability in clonal parasite virulence and human susceptibility to infection and the lack of definitive molecular predictors of outcome from either side of the host-parasite equation. Further, while several distinct mechanisms of pathogenesis have been studied in isolation, it is certain that multiple coincident mechanisms combine to determine the ultimate outcome. For these reasons, Chagas disease is best considered a collection of related but distinct illnesses. This review highlights the pathology and pathogenesis of the most common adverse sequela of T. cruzi infection-Chagas heart disease-and concludes with a discussion of key unanswered questions and a view to the future.


Assuntos
Cardiomiopatia Chagásica/patologia , Animais , Cardiomiopatia Chagásica/etiologia , Cardiomiopatia Chagásica/imunologia , Fibrose , Humanos , Miocardite , Miocárdio/patologia
15.
Cytokine ; 113: 285-290, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30037707

RESUMO

This study investigated the efficacy of the vaccine in liver of mice infected with the Trypanosoma cruzi (T. cruzi) and immunized with AdASP-2. For this purpose, histopathological analysis and gene expression of COX-2, TNF-alpha, TNFR, iNOS, cytochrome C, caspase-3, TLR4, IL-6 and IL10 were evaluated. The following groups were used in this study: Group 1 - Control Group (CTRL) animals received AdßGal vehicle; Group 2 - Infected Group (TC) animals were infected with T. cruzi; Group 3 - Immunized Group (AdASP-2): animals were immunized by AdASP-2 vaccine; Group 4 - Immunized and Infected Group (AdASP-2+TC) animals were infected with T. cruzi and immunized by AdSP-2 vaccine. A significant decrease of amastigote nests was noticed in the group of animals that were immunized with AdASP-2 and infected on the same day. COX-2 and TNF-alpha gene expressions increased in TC group, whereas TNF-alpha decreased in the TC+AdASP-2 group. TNFR expression was high in AdASP-2+TC group. iNOS expression was high for all experimental groups whereas cytochrome C decreased for all experimental groups. Caspase 3 increased in TC and TC+AdASP-2 groups. The gene expression of TLR4 and IL-10 showed an increase in AdASP-2+TC group. Finally, hepatic fibrosis was noticed to TC and AdASP-2 + TC groups. Taken together, our results demonstrated that vaccination with AdASP-2 was effective against the acute phase of experimental Chagas disease as a result of a more powerful and rapid immune response closely related to expression of some inflammatory genes, such as iNOS, TNF-alpha, TLR 4, and IL-10.


Assuntos
Cardiomiopatia Chagásica/imunologia , Cirrose Hepática/imunologia , Fígado/imunologia , Neuraminidase/imunologia , Vacinas Protozoárias/imunologia , Trypanosoma cruzi/imunologia , Adenoviridae , Animais , Caspase 3/imunologia , Cardiomiopatia Chagásica/parasitologia , Cardiomiopatia Chagásica/patologia , Cardiomiopatia Chagásica/prevenção & controle , Ciclo-Oxigenase 2/imunologia , Citocromos c/imunologia , Citocinas/imunologia , Feminino , Fígado/parasitologia , Fígado/patologia , Cirrose Hepática/parasitologia , Cirrose Hepática/patologia , Cirrose Hepática/prevenção & controle , Camundongos , Óxido Nítrico Sintase Tipo II/imunologia , Receptor 4 Toll-Like/imunologia
16.
Heart Vessels ; 34(1): 123-133, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30047012

RESUMO

Chronic Chagas heart disease (CCHD affects about 30% of patients with chronic Chagas disease (CCD). Systemic arterial hypertension (SAH) afflicts about 25% of patients with CCD. The association of CCHD with SAH (CCHD-SAH) predisposes patients to develop chronic heart failure. The role of cytokines in disease progression in patients with CCHD-SAH is unknown. Accordingly, the aim of this study was to evaluate the plasma levels of cytokines expressing the Th1, Th2, Th17 pattern, as well as Treg cytokines, TNF-alpha, IL-1ß, IL-8, IL-7 in patients with SAH-CCHD to get insight into the immunomodulation process in patients with this condition. Fifteen patients with CCHD, 22 patients with CCHD-SAH, and 28 controls were studied. All patients underwent history-taking, physical examination, 12-lead resting ECG, chest X-ray, and Doppler-echocardiogram. Ten of 15 (66%) patients with CCHD, and 16 of 22 (73%) patients with CCHD-SAH had decreased left ventricular ejection fraction (p > 0.05). Cytokines levels were performed on plasma samples using the ELISA method. Overall, proinflammatory, anti-inflammatory, and regulatory cytokine levels were increased in patients with CCHD-SAH in comparison to patients with CCHD and controls. However, such a difference was higher regarding IL-2, IL-5, IL-17, IL-12, and TNF-alpha cytokine levels, respectively. Cytokine levels were higher in CCHD patients in comparison to controls. Patients with CCHD-SAH have increased plasma levels of pro-inflammatory, anti-inflammatory, and regulatory cytokines in comparison with CCHD patients, thus suggesting a higher level of immunomodulation in patients with CCHD-SAH.


Assuntos
Cardiomiopatia Chagásica/imunologia , Citocinas/metabolismo , Hipertensão/imunologia , Linfócitos T Reguladores/metabolismo , Células Th1/metabolismo , Células Th17/metabolismo , Células Th2/metabolismo , Biomarcadores/metabolismo , Cardiomiopatia Chagásica/metabolismo , Doença Crônica , Progressão da Doença , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Hipertensão/metabolismo , Masculino , Pessoa de Meia-Idade , Linfócitos T Reguladores/imunologia , Células Th1/imunologia , Células Th17/imunologia , Células Th2/imunologia
17.
Front Immunol ; 9: 2791, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30559742

RESUMO

Chagas disease is caused by infection with the protozoan Trypanosoma cruzi and affects over 8 million people worldwide. In spite of a powerful innate and adaptive immune response in acute infection, the parasite evades eradication, leading to a chronic persistent infection with low parasitism. Chronically infected subjects display differential patterns of disease progression. While 30% develop chronic Chagas disease cardiomyopathy (CCC)-a severe inflammatory dilated cardiomyopathy-decades after infection, 60% of the patients remain disease-free, in the asymptomatic/indeterminate (ASY) form, and 10% develop gastrointestinal disease. Infection of genetically deficient mice provided a map of genes relevant for resistance to T. cruzi infection, leading to the identification of multiple genes linked to survival to infection. These include pathogen resistance genes (PRG) needed for intracellular parasite destruction, and genes involved in disease tolerance (protection against tissue damage and acute phase death-DTG). All identified DTGs were found to directly or indirectly inhibit IFN-γ production or Th1 differentiation. We hypothesize that the absolute need for DTG to control potentially lethal IFN-γ PRG activity leads to T. cruzi persistence and establishment of chronic infection. IFN-γ production is higher in CCC than ASY patients, and is the most highly expressed cytokine in CCC hearts. Key DTGs that downmodulate IFN-γ, like IL-10, and Ebi3/IL27p28, are higher in ASY patients. Polymorphisms in PRG and DTG are associated with differential disease progression. We thus hypothesize that ASY patients are disease tolerant, while an imbalance of DTG and IFN-γ PRG activity leads to the inflammatory heart damage of CCC.


Assuntos
Cardiomiopatia Chagásica/imunologia , Doença de Chagas/imunologia , Tolerância Imunológica/imunologia , Trypanosoma cruzi/imunologia , Progressão da Doença , Coração/parasitologia , Humanos , Interferon gama/imunologia , Interleucina-10/imunologia , Células Th1/imunologia , Células Th1/parasitologia
18.
Free Radic Biol Med ; 129: 227-236, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30248443

RESUMO

Elderly organisms are more susceptible to infectious diseases. However, the impact of aging on antiparasitic mechanisms, especially the nitric oxide pathway, is poorly understood. Using an integrated in vivo and in vitro model, we compared the severity of Trypanosoma cruzi infection in young and elderly (8 or 72 weeks old) mice. Forty C57BL/6 mice were randomized into four groups: Y-inf, young infected; Yn-inf, young uninfected; A-inf, aged infected; An-inf, aged uninfected. Parasitemia was measured daily, and animals were euthanized after 15 days of infection. Trypanosoma cruzi-induced inflammatory processes were analyzed in blood and heart samples, as well as in bone marrow-derived macrophages (BMDMs) co-cultured with splenocytes isolated from young or elderly mice. Our results indicated upregulated IgG2b and IL-17 production in elderly animals, which was not sufficient to reduce parasitemia, parasitic load and myocarditis to levels observed in young animals. The higher susceptibility of elderly mice to T. cruzi infection was accompanied by reduced cardiac inducible nitric oxide synthase (iNOS) gene expression, nitric oxide (NO) and IFN-γ levels, as well as an antagonistic upregulation of arginase-1 expression and arginase activity. The same responses were observed when BMDMs co-cultured with splenocytes from elderly mice were stimulated with T. cruzi antigens. Our findings indicate that elderly mice were more susceptible to T. cruzi infection, which was potentially related to an attenuated response to antigenic stimulation, inhibition of iNOS gene expression and NO production, and antagonistic upregulation of arginase gene expression and activity, which created favorable conditions for heart parasitism and myocarditis development.


Assuntos
Envelhecimento/genética , Arginase/genética , Cardiomiopatia Chagásica/genética , Doença de Chagas/genética , Óxido Nítrico Sintase Tipo II/genética , Parasitemia/genética , Trypanosoma cruzi/patogenicidade , Envelhecimento/imunologia , Animais , Antígenos de Protozoários/farmacologia , Arginase/sangue , Cardiomiopatia Chagásica/imunologia , Cardiomiopatia Chagásica/parasitologia , Doença de Chagas/imunologia , Doença de Chagas/parasitologia , Técnicas de Cocultura , Regulação da Expressão Gênica , Coração/parasitologia , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Imunoglobulina G/sangue , Imunoglobulina G/genética , Interferon gama/sangue , Interferon gama/genética , Interleucina-10/sangue , Interleucina-10/genética , Interleucina-17/sangue , Interleucina-17/genética , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/parasitologia , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico Sintase Tipo II/sangue , Parasitemia/imunologia , Índice de Gravidade de Doença , Transdução de Sinais , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Linfócitos T/parasitologia , Trypanosoma cruzi/imunologia
19.
Neuroimmunomodulation ; 25(3): 119-128, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30253402

RESUMO

Individuals who are infected with Trypanosoma cruzi develop chronic Chagas cardiomyopathy (CCC), which is a complication involving a series of immune pathogenetic mechanisms, although an association between immune and metabolic alterations was more recently proposed. Accordingly, we investigated the immuno-metabolic response in chagasic patients and their possible influence on CCC pathogenesis. To this end, T. cruzi-seropositive (asymptomatic or with CCC) and sero-negative individuals were studied. Serum tumour necrosis factor (TNF)-α, interleukin (IL)-6, adipocytokines and the expression of their receptors in peripheral blood mononuclear cell (PBMC) were evaluated, together with other factors influencing the immune response. CCC patients showed major metabolic and hormonal abnormalities, in parallel with increased IL-6 and leptin serum levels. TNF-α receptor s, leptin and adiponectin receptors (ObR and Adipo-Rs respectively), as well as PPAR-γ expression in PBMCs from CCC patients were compatible with a counteracting response leading to an unfavourable immune-metabolic profile. These results suggest that persistently increased levels of immune-metabolic pro-inflammatory mediators along with the adverse endocrine anti-inflammatory response of CCC individuals, may contribute to the underlying mechanisms dealing with myocardial tissue damage.


Assuntos
Cardiomiopatia Chagásica/imunologia , Cardiomiopatia Chagásica/metabolismo , Imunidade Celular/fisiologia , Síndrome Metabólica/imunologia , Síndrome Metabólica/metabolismo , Índice de Gravidade de Doença , Adulto , Biomarcadores/metabolismo , Cardiomiopatia Chagásica/fisiopatologia , Citocinas/imunologia , Citocinas/metabolismo , Eletrocardiografia/tendências , Feminino , Humanos , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Masculino , Síndrome Metabólica/fisiopatologia , Pessoa de Meia-Idade
20.
PLoS Negl Trop Dis ; 12(8): e0006617, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30067739

RESUMO

Cardiomyopathy is the most serious consequence of Chagas disease, a neglected human disorder caused by Trypanosoma cruzi infection. Because T. cruzi parasites invade cardiomyocytes, we sought to investigate whether these cells recognize the parasite in vivo by receptors signaling through the MyD88 adaptor, which mediates the activation pathway of most Toll-like receptors (TLRs) and IL-1/IL-18 receptors, and influence the development of acute cardiac pathology. First, we showed that HL-1 cardiac muscle cell line expresses MyD88 gene and protein at resting state and after T. cruzi infection. To evaluate the role in vivo of MyD88 expression in cardiomyocytes, we generated Mer+MyD88flox+/+ mice in which tamoxifen treatment is expected to eliminate the MyD88 gene exclusively in cardiomyocytes. This Cre-loxP model was validated by both PCR and western blot analysis; tamoxifen treatment of Mer+MyD88flox+/+ mice resulted in decreased MyD88 gene and protein expression in the heart, but not in the spleen, while had no effect on littermates. The elimination of MyD88 in cardiomyocytes determined a lower increase in CCL5, IFNγ and TNFα gene transcription during acute infection by T. cruzi parasites of the Y strain, but it did not significantly modify heart leukocyte infiltration and parasitism. Together, our results show that cardiomyocytes can sense T. cruzi infection through MyD88-mediated molecular pathways and contribute to the local immune response to the parasite. The strong pro-inflammatory response of heart-recruited leukocytes may overshadow the effects of MyD88 deficiency in cardiomyocytes on the local leukocyte recruitment and T. cruzi control during acute infection.


Assuntos
Cardiomiopatia Chagásica/imunologia , Fator 88 de Diferenciação Mieloide/metabolismo , Miócitos Cardíacos/metabolismo , Trypanosoma cruzi/imunologia , Animais , Linhagem Celular , Cardiomiopatia Chagásica/metabolismo , Citocinas/genética , Citocinas/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Genótipo , Humanos , Camundongos Knockout , Camundongos Transgênicos , Fator 88 de Diferenciação Mieloide/genética , Miocárdio/imunologia , Miocárdio/metabolismo , RNA Mensageiro , Moduladores Seletivos de Receptor Estrogênico/farmacologia , Tamoxifeno/farmacologia
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