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1.
Parasite Immunol ; 39(8)2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28543409

RESUMO

Cardiomyopathy is the most important clinical manifestation in the chronic phase of Chagas' disease because of its frequency, severity and impact on morbidity and mortality. The extracellular matrix degradation during cardiac remodeling in Trypanosoma cruzi infection is driven by matrix metalloproteinases (MMPs), primarily the MMP-2 and MMP-9 gelatinases. MMPs also regulate some molecules related to inflammation, such as growth factors, cytokines and chemokines. The involvement of MMP-2 and MMP-9 is not yet fully understood in Chagas' disease. It has been proposed that the gelatinases may have opposite effect on inflammation/regulation and cardiac remodeling. MMP-2 would participate in regulation, offering a protective role for cardiac damage in asymptomatic patients and would be a good marker for the initiation of changes in the heart. On the other hand, MMP-9 can be used as a marker for serious changes on the heart and would be associated with inflammation and fibrosis. Here, we consolidate all characteristics involving MMP-2 and MMP-9 in Chagas' disease based on current studies to clarify their participation on the inflammation/regulation and fibrosis, and the synergistic or antagonistic role between them.


Assuntos
Cardiomiopatia Chagásica/enzimologia , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Animais , Biomarcadores , Cardiomiopatia Chagásica/metabolismo , Cardiomiopatia Chagásica/patologia , Citocinas , Humanos , Inflamação/enzimologia , Inflamação/parasitologia , Inflamação/patologia , Trypanosoma cruzi
2.
Parasite Immunol ; 35(7-8): 214-23, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23607422

RESUMO

Chagas disease was discovered more than a hundred years ago, but its pathogenesis is still not completely understood. Autoimmunity is one of the mechanisms shown to contribute to its pathogenesis, which may indicate an important participation of B lymphocytes. Patients with Chagas disease have shown increased percentage of B cells producing IL-10. However, there are no reports of the phenotypic markers of B cells producing IL-10 in patients with Chagas disease. For the first time in the literature, we evaluated the phenotypic profile of distinct markers of B cells from peripheral blood of noninfected individuals and patients with Chagas disease. Our results showed that patients with Chagas disease had a higher expression of CD21 and CD24 on the surface of CD19+ B cells, while CD43 and CD23 were expressed equally in all groups. Moreover, the expression of MHC-II (HLA-DR), CD80, CD86, caspase-3, granzyme B and intracellular IL-10 and TGF-ß by CD19+ B cells was higher in patients with Chagas disease. The results of IL-10 production within CD19+ CD5+ CD1d+ B cells showed a higher percentage of this cytokine in patients with Chagas disease. Thus, our data bring a new knowledge about distinct markers of B cells in immune responses of Chagas disease.


Assuntos
Linfócitos B/imunologia , Doença de Chagas/imunologia , Adulto , Antígenos CD/análise , Linfócitos B/metabolismo , Biomarcadores/análise , Caspase 3/metabolismo , Doença de Chagas/metabolismo , Feminino , Antígenos HLA-DR/imunologia , Antígenos HLA-DR/metabolismo , Humanos , Imunofenotipagem , Interleucina-10/biossíntese , Interleucina-10/imunologia , Masculino , Pessoa de Meia-Idade , Fator de Crescimento Transformador beta/metabolismo , Trypanosoma cruzi/imunologia
3.
Scand J Immunol ; 76(3): 311-9, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22670682

RESUMO

Although the pathophysiology of Chagas disease is not completely understood, it is widely accepted that involvement of the immune response is critical in determining the outcome of the disease. In this context, CD4⁺ T cells may play an important role in generating different mechanisms of protection. In addition to effector and regulatory functions, CD4⁺ T cells may be also involved with lytic activities against the parasite and may have a relevant role on control of the infection. In this study, we have evaluated CD4⁺ T cells expressing cytotoxic and apoptosis markers in response to Trypanossoma cruzi infection in indeterminate (IND) and cardiac (CARD) patients with Chagas disease and non-infected individuals (NI). Our data demonstrated that: (1) CD4⁺ T cells presented higher ex vivo granzyme B expression in patients with Chagas disease compared with healthy individuals and that antigen induced a greater granzyme B expression in IND patients; (2) CD95L expression in CD4⁺ CD95⁺ T cells from IND patients is higher than in CARD and NI; (3) IND and CARD patients had an increased frequency of caspase-3 after in vitro stimulation and also expressed a high frequency of annexinV⁺ 7ADD⁺ within CD4⁺ T cells; (4) Lastly, a positive correlation was seen between cytotoxic molecules and CD45RO memory marker in CD4⁺ T cells and between caspase-3 and CD95L within CD4⁺ CD95⁺ T cells. These results suggest new insights into the functional competence of CD4⁺ T cells among the different clinical forms of Chagas disease, which will lead to a better understanding of their influence during immune responses against T. cruzi.


Assuntos
Apoptose/imunologia , Linfócitos T CD4-Positivos/imunologia , Doença de Chagas/imunologia , Subpopulações de Linfócitos T/imunologia , Adulto , Idoso , Animais , Biomarcadores/análise , Linfócitos T CD4-Positivos/metabolismo , Doença de Chagas/complicações , Doença de Chagas/metabolismo , Citotoxicidade Imunológica/imunologia , Feminino , Citometria de Fluxo , Granzimas/imunologia , Granzimas/metabolismo , Cardiopatias/etiologia , Cardiopatias/imunologia , Humanos , Proteína 1 de Membrana Associada ao Lisossomo/imunologia , Proteína 1 de Membrana Associada ao Lisossomo/metabolismo , Masculino , Pessoa de Meia-Idade , Subpopulações de Linfócitos T/metabolismo , Trypanosoma cruzi/imunologia
4.
Genes Immun ; 11(5): 374-83, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20535134

RESUMO

Congenital Toxoplasma gondii infection can result in intracranial calcification, hydrocephalus and retinochoroiditis. Acquired infection is commonly associated with ocular disease. Pathology is characterized by strong proinflammatory responses. Ligation of ATP by purinergic receptor P2X(7), encoded by P2RX7, stimulates proinflammatory cytokines and can lead directly to killing of intracellular pathogens. To determine whether P2X(7) has a role in susceptibility to congenital toxoplasmosis, we examined polymorphisms at P2RX7 in 149 child/parent trios from North America. We found association (FBAT Z-scores +/-2.429; P=0.015) between the derived C(+)G(-) allele (f=0.68; OR=2.06; 95% CI: 1.14-3.75) at single-nucleotide polymorphism (SNP) rs1718119 (1068T>C; Thr-348-Ala), and a second synonymous variant rs1621388 in linkage disequilibrium with it, and clinical signs of disease per se. Analysis of clinical subgroups showed no association with hydrocephalus, with effect sizes for associations with retinal disease and brain calcifications enhanced (OR=3.0-4.25; 0.004

Assuntos
Coriorretinite/genética , Predisposição Genética para Doença/genética , Receptores Purinérgicos P2/genética , Toxoplasmose Congênita/genética , Adulto , Brasil , Pré-Escolar , Coriorretinite/etiologia , Feminino , Estudo de Associação Genômica Ampla , Haplótipos/genética , Humanos , Padrões de Herança/genética , Desequilíbrio de Ligação , Modelos Logísticos , Masculino , América do Norte , Polimorfismo de Nucleotídeo Único/genética , Receptores Purinérgicos P2X7 , Toxoplasmose Congênita/complicações
5.
J Exp Med ; 179(2): 589-600, 1994 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-7905019

RESUMO

BALB/c mice infected with the intracellular protozoan Leishmania major mount a T helper cell 2 (Th2) response that fails to control growth of the parasite and results in the development of visceral leishmaniasis. Separation of CD4+ T cells into CD45RBhigh and CD45RBlow subsets showed that the L. major-specific Th2 cells were contained within the CD45RBlow population as these cells produced high levels of antigen-specific interleukin 4 (IL-4) in vitro and transferred a nonhealing response to L. major-infected C.B-17 scid mice. In contrast, the CD45RBhighCD4+ population contained L. major-reactive cells that produced interferon gamma (IFN-gamma) in vitro and transferred a healing Th1 response to L. major-infected C.B-17 scid mice. Transfer of the Th1 response by the CD45RBhigh population was inhibited by the CD45RBlow population by a mechanism that was dependent on IL-4. These data indicate that L. major-specific Th1 cells do develop in BALB/c mice, but their functional expression is actively inhibited by production of IL-4 by Th2 cells. In this response, the suppressed Th1 cells can be phenotypically distinguished from the suppressive Th2 cells by the level of expression of CD45RB. Although the CD45RBhigh population mediated a protective response to L. major, C.B-17 scid mice restored with this population developed a severe inflammatory response in the colon that was independent of L. major infection, and was prevented by cotransfer of the CD45RBlow population. The colitis appeared to be due to a dysregulated Th1 response as anti-IFN-gamma, but not anti-IL-4, prevented it. Taken together, the data show that the CD4+ T cell population identified by high level expression of the CD45RB antigen contains cells that mediate both protective and pathogenic Th1 responses and that the reciprocal CD45RBlow population can suppress both of these responses. Whether suppression of cell-mediated immunity is beneficial or not depends on the nature of the stimulus, being deleterious during L. major infection but crucial for control of potentially pathogenic inflammatory responses developing in the gut.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Imunidade Celular , Leishmania major/imunologia , Leishmaniose Cutânea/imunologia , Antígenos Comuns de Leucócito/imunologia , Animais , Anticorpos Monoclonais , Linfócitos T CD4-Positivos/transplante , Comunicação Celular , Colite/imunologia , Feminino , Imunoterapia Adotiva , Interferon gama/antagonistas & inibidores , Interferon gama/biossíntese , Interleucina-10/metabolismo , Interleucina-4/biossíntese , Antígenos Comuns de Leucócito/biossíntese , Camundongos , Camundongos Endogâmicos BALB C , Camundongos SCID , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/transplante
6.
Scand J Immunol ; 72(6): 529-39, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21044127

RESUMO

The clinical manifestations of human Chagas disease are associated with distinct and complex host-parasite interactions that directly involve the host's immune system. In this study, we analysed the relationship between the production of intracytoplasmic cytokines after in vitro stimulation with the recombinant antigens CRA (cytoplasmatic repetitive antigen) or FRA (flagellar repetitive antigen) from Trypanosoma cruzi and the chronic cardiac or indeterminate clinical forms of Chagas disease. The chagasic patient groups consisted of 39 individuals, selected at the Chagas Disease Unit of the Oswaldo Cruz University Hospital, whom presented either a cardiac form without cardiac dilatation (CARD 1), cardiac form with cardiac dilatation (CARD 2) or indeterminate form (IND). Blood samples were obtained from these patients and cultured in the presence of CRA or FRA. The cytokines produced by lymphocytes and monocytes after antigen stimulation were analysed by flow cytometry. Our results showed that the IFN-γ and TNF-α, produced by CD8+ T lymphocytes after in vitro stimulation with CRA, differed among chagasic patients with CARD 1, CARD 2 or IND. We propose that these cytokines could be utilized as immunological markers for clinical cardiac forms of Chagas disease. In a prospective study of patients presenting IND and CARD 1, the assay performed in this paper could serve as a tool to monitor therapeutic interventions, thus improving the patient's quality of life.


Assuntos
Antígenos de Protozoários/imunologia , Cardiomiopatia Chagásica/imunologia , Citocinas/biossíntese , Trypanosoma cruzi/imunologia , Adulto , Idoso , Biomarcadores/metabolismo , Células Cultivadas , Cardiomiopatia Chagásica/diagnóstico , Progressão da Doença , Feminino , Flagelos/imunologia , Humanos , Linfócitos/imunologia , Masculino , Pessoa de Meia-Idade , Monócitos/imunologia , Proteínas Recombinantes/imunologia
7.
Trials ; 21(1): 328, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32293523

RESUMO

BACKGROUND: Chagas disease (CD) continues to be a neglected infectious disease with one of the largest burdens globally. Despite the modest cure rates in adult chronic patients and its safety profile, benznidazole (BNZ) is still the drug of choice. Its current recommended dose is based on nonrandomized studies, and efficacy and safety of the optimal dose of BNZ have been scarcely analyzed in clinical trials. METHODS/DESIGN: MULTIBENZ is a phase II, randomized, noninferiority, double-blind, multicenter international clinical trial. A total of 240 patients with Trypanosoma CD in the chronic phase will be recruited in four different countries (Argentina, Brazil, Colombia, and Spain). Patients will be randomized to receive BNZ 150 mg/day for 60 days, 400 mg/day for 15 days, or 300 mg/day for 60 days (comparator arm). The primary outcome is the efficacy of three different BNZ therapeutic schemes in terms of dose and duration. Efficacy will be assessed according to the proportion of patients with sustained parasitic load suppression in peripheral blood measured by polymerase chain reaction. The secondary outcomes are related to pharmacokinetics and drug tolerability. The follow-up will be 12 months from randomization to end of study participation. Recruitment was started in April 2018. CONCLUSION: This is a clinical trial conducted for the assessment of different dose schemes of BNZ compared with the standard treatment regimen for the treatment of CD in the chronic phase. MULTIBENZ may help to clarify which is the most adequate BNZ regimen in terms of efficacy and safety, predicated on sustained parasitic load suppression in peripheral blood. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03191162. Registered on 19 June 2017.


Assuntos
Doença de Chagas/tratamento farmacológico , Doenças Negligenciadas/parasitologia , Nitroimidazóis/uso terapêutico , Tripanossomicidas/uso terapêutico , Trypanosoma cruzi/isolamento & purificação , Adulto , Assistência ao Convalescente , Argentina/epidemiologia , Brasil/epidemiologia , Estudos de Casos e Controles , Doença de Chagas/parasitologia , Doença Crônica , Colômbia/epidemiologia , Método Duplo-Cego , Feminino , Humanos , Masculino , Nitroimidazóis/farmacocinética , Carga Parasitária/estatística & dados numéricos , Segurança , Espanha/epidemiologia , Resultado do Tratamento , Tripanossomicidas/farmacocinética , Trypanosoma cruzi/genética
8.
Scand J Immunol ; 69(6): 521-8, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19439013

RESUMO

RATIONALE: Patients with chronic Schistosoma mansoni infection show lower anti-soluble egg antigen (SEA) proliferation responses and higher responses to soluble worm antigen preparation (SWAP). OBJECTIVE: To compare the activation status and proliferation response of peripheral blood mononuclear cells (PBMC) of infected (XTO) and egg-negative individuals (NI) living in the same endemic area. METHODS: XTO (n = 51) and NI individuals from the same geographical area (n = 37) and healthy blood donors (n = 22) were evaluated before and after stimulation with SEA and SWAP. The expression of activation markers (CD4(+) HLADR(+), CD8(high+)HLA-DR(+) and CD8(+) CD28(+)) and proliferation assay was assessed by flow cytometry. FINDINGS: PBMC from infected patients showed lower frequency of CD4(+) but no change in CD8(+) T cells when compared with the healthy donor group. The ratio CD4(+)/CD8(+) was 1.3, 0.6 and 0.5 in healthy donors, infected and non-infected individuals, respectively. The HLA-DR(+) expression on CD8(+) was higher in PBMC from infected and non-infected individuals than from healthy donors, but similar in both total lymphocytes and CD4(+) populations. No intergroup proliferation response differences were observed in CD4(+) and CD8(+) PBMC unstimulated and stimulated with SEA and SWAP. The SEA but not SWAP-stimulated cells showed a decrease in the expression of phosphorylated extracellular signal-regulated kinase (ERK1/2). CONCLUSIONS: XTO and NI individuals living in the same area presented a smaller per cent of CD4(+) and a higher per cent of CD8(+) cells. The activation by either CD8(high+)HLA-DR(+) or CD8(high+)HLA-DR(+)/CD8(+) was enhanced and decreased in XTO and NI by CD8(+) CD28(+) and CD8(+) CD28(+)/CD8(+) when compared with healthy donor. ERK phosphorylation was attenuated in XTO and NI individuals when stimulated with SEA but not SWAP.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Esquistossomose mansoni/imunologia , Subpopulações de Linfócitos T/imunologia , Adolescente , Adulto , Animais , Antígenos de Helmintos/imunologia , Antígenos CD28/imunologia , Citometria de Fluxo , Antígenos HLA-DR/imunologia , Antígenos HLA-DR/metabolismo , Humanos , Pessoa de Meia-Idade , Proteína Quinase 1 Ativada por Mitógeno/imunologia , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/imunologia , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Fosforilação , Schistosoma mansoni/imunologia , Transdução de Sinais/imunologia
9.
Clin Exp Dermatol ; 34(8): e709-11, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20055840

RESUMO

Acute generalized exanthematous pustulosis (AGEP) is an uncommon disease, which presents as a nonfollicular erythematous sterile pustular eruption. More than 90% of the cases are induced by adverse drug reactions, often triggered by anti-infectious systemic drugs. We report a case of itraconazole-induced AGEP in a 22-year-old man, with an assessment of his cytokine/chemokine production and drug-specific cell reactivity. We found that AGEP, like other T cell-mediated drug eruptions, alters the immunological status of the patient, probably favouring T-cell activation, recruitment and regulation. Few cases of itraconazole-induced AGEP have been described in the literature, and to our knowledge, this is the first report in which the cellular immunological features are assessed.


Assuntos
Pustulose Exantematosa Aguda Generalizada/imunologia , Antifúngicos/efeitos adversos , Toxidermias/imunologia , Itraconazol/efeitos adversos , Ativação Linfocitária/imunologia , Pustulose Exantematosa Aguda Generalizada/induzido quimicamente , Humanos , Masculino , Linfócitos T/fisiologia , Adulto Jovem
10.
Antimicrob Agents Chemother ; 52(8): 2780-6, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18519730

RESUMO

The objective of the present study was to test the hypothesis that treatment of schistosomiasis mansoni with praziquantel can alter significantly the immune response of patients and generate a reversal of the level of fibrosis. Peripheral blood mononuclear cell (PBMC) samples were collected from, and abdominal ultrasound examinations conducted on, volunteers infected with Schistosoma mansoni and living in an area where the disease is endemic, both prior to and one year after treatment with praziquantel. Subjects were classified into groups according to the level of pathology (i.e., absent, incipient, moderate, or severe fibrosis). PBMCs were stimulated with schistosome soluble egg antigens (SEA), and the levels of production of the cytokines gamma interferon (IFN-gamma), tumor necrosis factor alpha, transforming growth factor beta, and interleukin-4 (IL-4), IL-10, and IL-13 were determined. The chemotherapy was effective in reducing morbidity, particularly for individuals presenting with severe fibrosis. When levels of cytokine production in posttreatment PBMC cultures stimulated by SEA were categorized as low or high, significant differences in the distribution of IL-13 levels between groups presenting with or not presenting with fibrosis were established. Comparison of pre- and posttreatment SEA-induced cytokine levels in individuals who had experienced no change in the grade of fibrosis following chemotherapy revealed that the level of IFN-gamma decreased in subjects with fibrosis whereas that of IL-10 decreased in individuals with and without fibrosis. The data suggest that chemotherapy is effective in reducing the morbidity of the disease and that the level of IL-13 may be a useful indicator of the persistence of fibrosis following treatment.


Assuntos
Anti-Helmínticos/uso terapêutico , Citocinas/sangue , Praziquantel/uso terapêutico , Esquistossomose mansoni/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Brasil , Feminino , Humanos , Interferon gama/sangue , Interleucina-10/sangue , Interleucina-13/sangue , Interleucina-4/sangue , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Masculino , Pessoa de Meia-Idade , Esquistossomose mansoni/sangue , Esquistossomose mansoni/diagnóstico por imagem , Fator de Crescimento Transformador beta/sangue , Ultrassonografia , Adulto Jovem
11.
Parasitology ; 135(11): 1337-42, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18664306

RESUMO

Chagas' disease is one of the few functional gastrointestinal disorders for which a causative agent has been identified. However, some pathological aspects of the chagasic megasyndromes are still incompletely understood. Chagasic megacolon is characterized by an inflammatory process, organ dilatation and neuronal reduction in both plexuses of the enteric nervous system (ENS). Although some studies on the ENS in Chagas' disease have been performed, the process of neuronal destruction and neuronal regeneration still remains unclear. Our hypothesis is that the regeneration process of the ENS may be involved with the mechanisms that prevent or retard organ dilatation and chagasic megacolon development. For that reason, we evaluated the neuronal regeneration with the marker GAP-43 in the colon's neuronal plexuses from chagasic patients with megacolon, and from non-infected individuals. Visual examination and quantitative analysis revealed an increased neuronal regeneration process in the dilated portion from chagasic patients when compared with the non-dilated portion and with non-infected individuals. We believe that this increased regeneration can be interpreted as an accentuated neuronal plasticity that may be a response of the ENS to avoid megacolon propagation to the entire organ and maintain the colon functional innervation.


Assuntos
Doença de Chagas/complicações , Doença de Chagas/patologia , Sistema Nervoso Entérico/fisiopatologia , Proteína GAP-43/metabolismo , Megacolo/patologia , Plasticidade Neuronal/fisiologia , Animais , Doença de Chagas/parasitologia , Colo/inervação , Humanos , Megacolo/etiologia , Megacolo/metabolismo , Plexo Mientérico/fisiopatologia , Regeneração Nervosa/fisiologia , Plexo Submucoso/fisiopatologia , Trypanosoma cruzi
12.
Parasitology ; 135(8): 943-53, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18598576

RESUMO

Evolutionary and closer structural relationships are demonstrated by phylogenetic analysis, peptide prediction and molecular modelling between Solanum tuberosum apyrase, Schistosoma mansoni SmATPase 2 and Leishmania braziliensis NDPase. Specific protein domains are suggested to be potentially involved in the immune response, and also seem to be conserved during host and parasite co-evolution. Significant IgG antibody reactivity was observed in sera from patients with American cutaneous leishmaniasis (ACL) and schistosomiasis using potato apyrase as antigen in ELISA. S. mansoni adult worm or egg, L. braziliensis promastigote (Lb) and Trypanosoma cruzi epimastigote (EPI) have ATP diphosphohydrolases, and antigenic preparations of them were evaluated. In ACL patients, IgG seropositivity was about 43% and 90% for Lb and potato apyrase, respectively, while IgM was lower (40%) or IgG (100%) seropositivity for both soluble egg (SEA) and adult worm (SWAP) antigens was higher than that found for potato apyrase (IgM=10%; IgG=39%). In Chagas disease, IgG seropositivity for EPI and potato apyrase was 97% and 17%, respectively, while the IgM was low (3%) for both antigens. The study of the conserved domains from both parasite proteins and potato apyrase could lead to the development of new drug targets or molecular markers.


Assuntos
Apirase/imunologia , Sequência Conservada/imunologia , Mapeamento de Epitopos , Parasitos/enzimologia , Parasitos/imunologia , Solanum tuberosum/enzimologia , Sequência de Aminoácidos , Animais , Anticorpos Antiprotozoários/imunologia , Apirase/química , Doença de Chagas/sangue , Doença de Chagas/imunologia , Humanos , Leishmania braziliensis/enzimologia , Leishmania braziliensis/genética , Leishmania braziliensis/imunologia , Leishmaniose Cutânea/sangue , Leishmaniose Cutânea/imunologia , Dados de Sequência Molecular , Parasitos/genética , Filogenia , Estrutura Terciária de Proteína , Schistosoma mansoni/enzimologia , Schistosoma mansoni/genética , Schistosoma mansoni/imunologia , Esquistossomose/sangue , Esquistossomose/imunologia , Alinhamento de Sequência
13.
Exp Parasitol ; 120(3): 269-74, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18786531

RESUMO

A detailed investigation has been carried out about the serological profiles of groups of dogs experimentally infected with metacyclic (MT) or blood (BT) trypomastigotes of Berenice-78 Trypanosoma cruzi strain. Peripheral blood was collected from infected dogs and uninfected controls, weekly during 35 days following the acute phase of infection, and immunoglobulin profiles were determined by ELISA. Dogs infected with BT exhibited unaltered levels of IgG2, increases in IgM, IgE, IgA, IgG and IgG1. In contrast, dogs infected with MT presented unaltered levels of IgE and IgG1 and an increase in IgM, IgA, IgG and IgG2 levels. Compared with the MT group, animals infected with BT showed significant increases in IgM on days 7, 14 and 28, in IgA on days 7, 14 and 21, in IgE on days 7 and 14, in IgG on days 14 and 28, and in IgG1 on days 7, 14 and 21. Parasitemia levels of the infected animals were measured over the same time period. No correlations were found between the immunoglobulin profiles and the parasitemia levels. The results demonstrated that the inoculum source (BT or MT) influence the immunoglobulin isotype profile that may drive distinct outcome of acute canine Chagas disease.


Assuntos
Doença de Chagas/imunologia , Isotipos de Imunoglobulinas/sangue , Trypanosoma cruzi/imunologia , Doença Aguda , Animais , Doença de Chagas/parasitologia , Cães , Ensaio de Imunoadsorção Enzimática , Feminino , Imunoglobulina A/biossíntese , Imunoglobulina A/sangue , Imunoglobulina E/biossíntese , Imunoglobulina E/sangue , Imunoglobulina G/biossíntese , Imunoglobulina G/sangue , Isotipos de Imunoglobulinas/biossíntese , Imunoglobulina M/biossíntese , Imunoglobulina M/sangue , Cinética , Estudos Longitudinais , Camundongos , Parasitemia/imunologia , Parasitemia/parasitologia
14.
Mem Inst Oswaldo Cruz ; 103(5): 423-30, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18797753

RESUMO

Chagas disease is a major public health problem in Bolivia. In the city of Cochabamba, 58% of the population lives in peripheral urban districts ("popular zones") where the infection prevalence is extremely high. From 1995 to 1999, we studied the demographics of Chagas infections in children from five to 13 years old (n = 2218) from the South zone (SZ) and North zone (NZ) districts, which differ in social, environmental, and agricultural conditions. Information gathered from these districts demonstrates qualitative and quantitative evidence for the active transmission of Trypanosoma cruzi in urban Cochabamba. Seropositivity was high in both zones (25% in SZ and 19% in NZ). We observed a high risk of infection in children from five to nine years old in SZ, but in NZ, a higher risk occurred in children aged 10-13, with odds ratio for infection three times higher in NZ than in SZ. This difference was not due to triatomine density, since more than 1,000 Triatoma infestans were captured in both zones, but was possibly secondary to the vector infection rate (79% in SZ and 37% in NZ). Electrocardiogram abnormalities were found to be prevalent in children and pre-adolescents (SZ = 40%, NZ = 17%), indicating that under continuous exposure to infection and re-infection, a severe form of the disease may develop early in life. This work demonstrates that T. cruzi infection should also be considered an urban health problem and is not restricted to the rural areas and small villages of Bolivia.


Assuntos
Doença de Chagas/transmissão , Conhecimentos, Atitudes e Prática em Saúde , Insetos Vetores/parasitologia , Triatoma/parasitologia , Trypanosoma cruzi/isolamento & purificação , Adolescente , Animais , Bolívia/epidemiologia , Gatos , Bovinos , Doença de Chagas/diagnóstico , Doença de Chagas/epidemiologia , Criança , Pré-Escolar , Cães , Feminino , Humanos , Masculino , Densidade Demográfica , Prevalência , Coelhos , Fatores de Risco , Estudos Soroepidemiológicos , Ovinos , Fatores Socioeconômicos , População Urbana
16.
J Clin Invest ; 84(3): 1028-31, 1989 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2503542

RESUMO

Cord blood mononuclear cells (CBMC) of neonates born of mothers with Chagas' disease or schistosomiasis exhibited strong proliferative responses against idiotypes expressed on antibodies with specificity for Trypanosoma cruzi or Schistosoma mansoni antigens, respectively. These immunoaffinity-purified preparations were stimulatory if they were prepared from pools of patients' sera or from the mother's own serum, taken early during her pregnancy. These CBMC did not respond to normal immunoglobulin, and CBMC of neonates born of uninfected mothers did not respond to antibodies against either T. cruzi or S. mansoni, or normal immunoglobulin preparations. We propose that in utero exposure of a fetus to some idiotypes expressed on placentally transferred antibodies induces anti-Id T lymphocyte sensitization, which we detect as a proliferative response by CBMC exposed to immunoaffinity-purified antibodies expressing the relevant idiotypes. This is the first experimental evidence that children born of mothers with chronic infections undergo natural in utero idiotypic manipulations and are born possessing cellular anti-Id reactivity.


Assuntos
Doença de Chagas/imunologia , Sangue Fetal/imunologia , Imunidade Materno-Adquirida , Idiótipos de Imunoglobulinas/imunologia , Esquistossomose mansoni/imunologia , Animais , Anticorpos Anti-Helmínticos/fisiologia , Anticorpos Antiprotozoários/fisiologia , Feminino , Humanos , Imunoglobulinas/fisiologia , Ativação Linfocitária , Mães , Fito-Hemaglutininas/farmacologia , Gravidez
17.
Am J Trop Med Hyg ; 77(3): 495-9, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17827366

RESUMO

This study was conducted in Posse, a rural community in Goiàs, Brazil. Persons were recruited into the study through house-to-house sampling of all houses in the sampled area. Blood samples were collected for seropositivity assessments for Trypanosoma cruzi and an electrocardiogram was assessed using a portable system. The results demonstrate significant differences between seropositive and seronegative persons for electrocardiographic (ECG)-derived traits. Seropositive persons had substantially longer QRS and QT intervals than seronegative persons. The PR interval was significantly different between seropositive and seronegative persons. Conduction abnormalities were observed more frequently in seropositive than seronegative persons. Right bundle branch block, an ECG abnormality typical of Chagas disease, was observed in 15% of seropositive persons compared with less than 1% of seronegative persons. Results indicate that T. cruzi infection and subsequent Chagas disease will continue to be major health problems for the foreseeable future in this typical rural area of Brazil.


Assuntos
Doença de Chagas/complicações , Doença de Chagas/imunologia , Cardiopatias/complicações , Animais , Brasil , Doença de Chagas/sangue , Eletrocardiografia , Feminino , Humanos , Masculino , Trypanosoma cruzi/imunologia
18.
Clin Microbiol Infect ; 13(11): 1083-8, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17727687

RESUMO

The immunological mechanisms involved in the development of duodenal ulcer, especially in childhood, are unclear. Helicobacter pylori-positive children and adults, with and without duodenal ulcer, were therefore compared with respect to CD4(+) T-cells, and CD8(+) T-cells, B-cells and B1a-cells, as well as cell activation (CD4(+)/HLA-DR(+) and CD8(+)/HLA-DR(+)) and co-stimulatory (CD4(+)/CD28(+) and CD8(+)/CD28(+)) markers, in peripheral blood. Children with and without duodenal ulcer differed significantly. In particular, there was a phenotypic change in CD8(+) T-cells from children with ulcer that involved a 200% increase in the number of CD8(+)/HLA-DR(+) cells/mm(3) and a decrease of 34.2% in the number of CD8(+)/CD28(+) cells/mm(3). This phenotype of chronically activated memory CD8(+) T-cells, which has also been observed in patients with AIDS and tuberculosis, is associated with disease severity and progression. A lower frequency of B1a-cells was also observed in the group of children with ulcer. Conversely, no difference between infected adults with and without ulcer was observed, but the percentage of CD4(+)/HLA-DR(+) cells was lower in adults with ulcer, suggesting that a down-regulated immune response may play a role in the development of duodenal ulcer in adults. Gastric inflammation correlated positively with CD4(+) and chronically activated CD4(+) T-cells in children and adults without duodenal ulcer, respectively. These results suggest that there are differences in the immunophenotyping profile between H. pylori-positive children and adults with duodenal ulcer, indicating the possibility of distinct immune mechanisms in the development of the disease according to age.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Úlcera Duodenal/imunologia , Infecções por Helicobacter/imunologia , Helicobacter pylori/imunologia , Adolescente , Adulto , Fatores Etários , Idoso , Linfócitos B/imunologia , Criança , Úlcera Duodenal/sangue , Feminino , Antígenos HLA-DR/imunologia , Infecções por Helicobacter/microbiologia , Humanos , Imunofenotipagem/métodos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Subpopulações de Linfócitos T/imunologia
19.
Vet Immunol Immunopathol ; 115(1-2): 135-45, 2007 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-17097741

RESUMO

Recent studies suggest that asymptomatic dogs infected with canine visceral leishmaniasis (CVL) develop a Th1 immunological profile whilst oligosymptomatic and symptomatic CVL-infected animals present a Th2 profile. In the present study, an RT-PCR method has been standardised and employed to evaluate the frequency and the semi-quantitative level of expression of the cytokines IL-4, IL-10, IL-12, INF-gamma and TNF-alpha in splenocytes of 30 dogs naturally infected with Leishmania chagasi and of 7 non-infected dogs (NID). An increase in the level of expression of IL-12 (p=0.059) was detected in all CVL-infected dogs compared with NID. In dogs exhibiting high parasitism, the frequency of expression of IL-10 was higher (p=0.011) than in animals presenting low parasitism or medium parasitism (MP) and in NID animals, whilst the level of expression of IL-10 was higher (p=0.0094) than in animals exhibiting MP and in the NID group. Positive correlations between the levels of expression of IL-10 with respect to the progression of the disease (IL-10: r=0.3510; p=0.0337) and the levels of expression of IL-10 and INF-gamma increase in parasitism (IL-10: r=0.3428; p=0.0438 and INF-gamma: r=0.4690; p=0.0045) were observed. Such data suggest that CVL is marked by a balanced production of Th1 and Th2 cytokines, with a predominant accumulation of IL-10 as a consequence of an increase in parasitic load and progression of the disease, and INF-gamma was related with the increase in parasitic load.


Assuntos
Citocinas/genética , Doenças do Cão/imunologia , Leishmania infantum , Leishmaniose Visceral/veterinária , Baço/imunologia , Animais , Cães , Leishmaniose Visceral/imunologia , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa
20.
Front Biosci ; 11: 1158-63, 2006 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-16146804

RESUMO

The understanding of the role of the immune response in the development of gastrointestinal and cardio-digestive (CD) forms of Chagas disease has received little attention. In this paper, the commitment of each leukocyte population of peripheral blood to the production of IFN-gamma, TNF-alpha, IL-12, IL-4, IL-5 and IL-10 was studied in patients with the CD form of Chagas disease. The data show that cells from patients with the CD form of the disease have distinct cytokine profiles when compared with the other clinical forms of Chagas disease and suggest that eosinophils are the major source of cytokine production in this clinical entity. The data presented in this paper demonstrate that patients with CD form can be distinguished from patients with gastrointestinal or cardiac forms of the disease by the distinct cytokine profile of peripheral blood cells.


Assuntos
Doença de Chagas/diagnóstico , Doença de Chagas/patologia , Adulto , Idoso , Animais , Células Cultivadas , Doença de Chagas/metabolismo , Citocinas/metabolismo , Eosinófilos/metabolismo , Eosinófilos/parasitologia , Feminino , Humanos , Interferon gama/metabolismo , Interleucina-10/metabolismo , Interleucina-12/metabolismo , Interleucina-4/metabolismo , Interleucina-5/metabolismo , Leucócitos/metabolismo , Leucócitos/parasitologia , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Fenótipo , Trypanosoma cruzi/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
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