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Rodríguez-Morales O, Roldán FJ, Vargas-Barrón J, Parra-Benítez E, Medina-García MDL, Vergara-Bello E, Arce-Fonseca M. Echocardiographic Findings in Canine Model of Chagas Disease Immunized with DNA Trypanosoma cruzi Genes. Animals (Basel) 2020; 10:E648. [PMID: 32283649 PMCID: PMC7222844 DOI: 10.3390/ani10040648] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Revised: 04/03/2020] [Accepted: 04/03/2020] [Indexed: 02/06/2023] Open
Abstract
Chagas disease (ChD) is considered an emerging disease in the USA and Europe. Trypanosoma cruzi genes encoding a trans-sialidase protein and an amastigote-specific glycoprotein were tested as vaccines in canine model. The aim for this study was determining the prophylactic effect of these genes in experimentally infected dogs by echocardiography evaluation to compare with our findings obtained by other techniques published previously. Low fractional-shortening values of non-vaccinated dogs suggested an impairment in general cardiac function. Low left ventricular ejection fraction values found in infected dogs suggested myocardial injury regardless of whether they were vaccinated. Low left ventricular diastolic/systolic diameters suggested that progressive heart damage or heart dilation could be prevented by DNA vaccination. Systolic peak time was higher in non-vaccinated groups, increasing vulnerability to malignant arrhythmias and sudden death. High left ventricular volume suggested a decrease in wall thickness that might lead to increased size of the heart cavity, except in the pBCSP plasmid-vaccinated dogs. There was an echocardiographic evidence of left ventricular dilation and reduction in systolic function in experimental chagasic dogs. Echocardiography allowed a more complete follow-up of the pathological process in the living patient than with other techniques like electrocardiography, anatomopathology, and histopathology, being the method of choice for characterizing the clinical stages of ChD.
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Affiliation(s)
- Olivia Rodríguez-Morales
- Department of Molecular Biology, National Institute of Cardiology “Ignacio Chávez”, Juan Badiano No. 1, Col. Sección XVI, Tlalpan, Mexico City 14080, Mexico; (O.R.-M.); (E.P.-B.); (M.d.L.M.-G.); (E.V.-B.)
| | - Francisco-Javier Roldán
- Department of Echocardiography, National Institute of Cardiology “Ignacio Chávez”, Juan Badiano No. 1, Col. Sección XVI, Tlalpan, Mexico City 14080, Mexico; (F.-J.R.); (J.V.-B.)
| | - Jesús Vargas-Barrón
- Department of Echocardiography, National Institute of Cardiology “Ignacio Chávez”, Juan Badiano No. 1, Col. Sección XVI, Tlalpan, Mexico City 14080, Mexico; (F.-J.R.); (J.V.-B.)
| | - Enrique Parra-Benítez
- Department of Molecular Biology, National Institute of Cardiology “Ignacio Chávez”, Juan Badiano No. 1, Col. Sección XVI, Tlalpan, Mexico City 14080, Mexico; (O.R.-M.); (E.P.-B.); (M.d.L.M.-G.); (E.V.-B.)
| | - María de Lourdes Medina-García
- Department of Molecular Biology, National Institute of Cardiology “Ignacio Chávez”, Juan Badiano No. 1, Col. Sección XVI, Tlalpan, Mexico City 14080, Mexico; (O.R.-M.); (E.P.-B.); (M.d.L.M.-G.); (E.V.-B.)
| | - Emilia Vergara-Bello
- Department of Molecular Biology, National Institute of Cardiology “Ignacio Chávez”, Juan Badiano No. 1, Col. Sección XVI, Tlalpan, Mexico City 14080, Mexico; (O.R.-M.); (E.P.-B.); (M.d.L.M.-G.); (E.V.-B.)
| | - Minerva Arce-Fonseca
- Department of Molecular Biology, National Institute of Cardiology “Ignacio Chávez”, Juan Badiano No. 1, Col. Sección XVI, Tlalpan, Mexico City 14080, Mexico; (O.R.-M.); (E.P.-B.); (M.d.L.M.-G.); (E.V.-B.)
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de Souza SM, Vieira PMDA, Roatt BM, Reis LES, da Silva Fonseca K, Nogueira NC, Reis AB, Tafuri WL, Carneiro CM. Dogs infected with the blood trypomastigote form of Trypanosoma cruzi display an increase expression of cytokines and chemokines plus an intense cardiac parasitism during acute infection. Mol Immunol 2013; 58:92-7. [PMID: 24317279 DOI: 10.1016/j.molimm.2013.11.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2013] [Revised: 11/05/2013] [Accepted: 11/09/2013] [Indexed: 02/06/2023]
Abstract
The recent increase in immigration of people from areas endemic for Chagas disease (Trypanosoma cruzi) to the United States and Europe has raised concerns about the transmission via blood transfusion and organ transplants in these countries. Infection by these pathways occurs through blood trypomastigotes (BT), and these forms of T. cruzi are completely distinct of metacyclic trypomastigotes (MT), released by triatomine vector, in relation to parasite-host interaction. Thus, research comparing infection with these different infective forms is important for explaining the potential impacts on the disease course. Here, we investigated tissue parasitism and relative mRNA expression of cytokines, chemokines, and chemokine receptors in the heart during acute infection by MT or BT forms in dogs. BT-infected dogs presented a higher cardiac parasitism, increased relative mRNA expression of pro-inflammatory and immunomodulatory cytokines and of the chemokines CCL3/MIP-1α, CCL5/RANTES, and the chemokine receptor CCR5 during the acute phase of infection, as compared to MT-infected dogs. These results suggest that infection with BT forms may lead to an increased immune response, as revealed by the cytokines ratio, but this kind of immune response was not able to control the cardiac parasitism. Infection with the MT form presented an increase in the relative mRNA expression of IL-12p40 as compared to that of IL-10 or TGF-β1. Correlation analysis showed increased relative mRNA expression of IFN-γ as well as IL-10, which may be an immunomodulatory response, as well as an increase in the correlation of CCL5/RANTES and its CCR5 receptor. Our findings revealed a difference between inoculum sources of T. cruzi, as vectorial or transfusional routes of T. cruzi infection may trigger distinct parasite-host interactions during the acute phase, which may influence immunopathological aspects of Chagas disease.
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Affiliation(s)
- Sheler Martins de Souza
- Laboratório de Imunopatologia, Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, Minas Gerais, Brazil
| | - Paula Melo de Abreu Vieira
- Laboratório de Imunopatologia, Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, Minas Gerais, Brazil; Departamento de Ciências Biológicas, Instituto de Ciências Exatas e Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, Minas Gerais, Brazil
| | - Bruno Mendes Roatt
- Laboratório de Imunopatologia, Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, Minas Gerais, Brazil
| | - Levi Eduardo Soares Reis
- Laboratório de Imunopatologia, Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, Minas Gerais, Brazil; Laboratório de Pesquisas Clínicas, Departamento de Análises Clínicas, Escola de Farmácia, Universidade Federal de Ouro Preto, Ouro Preto, Minas Gerais, Brazil
| | - Kátia da Silva Fonseca
- Laboratório de Imunopatologia, Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, Minas Gerais, Brazil
| | - Nívia Carolina Nogueira
- Laboratório de Imunopatologia, Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, Minas Gerais, Brazil
| | - Alexandre Barbosa Reis
- Laboratório de Imunopatologia, Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, Minas Gerais, Brazil; Laboratório de Pesquisas Clínicas, Departamento de Análises Clínicas, Escola de Farmácia, Universidade Federal de Ouro Preto, Ouro Preto, Minas Gerais, Brazil
| | - Washington Luiz Tafuri
- Laboratório de Imunopatologia, Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, Minas Gerais, Brazil
| | - Cláudia Martins Carneiro
- Laboratório de Imunopatologia, Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, Minas Gerais, Brazil; Laboratório de Pesquisas Clínicas, Departamento de Análises Clínicas, Escola de Farmácia, Universidade Federal de Ouro Preto, Ouro Preto, Minas Gerais, Brazil.
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Arce-Fonseca M, Ballinas-Verdugo MA, Zenteno ERA, Suárez-Flores D, Carrillo-Sánchez SC, Alejandre-Aguilar R, Rosales-Encina JL, Reyes PA, Rodríguez-Morales O. Specific humoral and cellular immunity induced by Trypanosoma cruzi DNA immunization in a canine model. Vet Res 2013; 44:15. [PMID: 23497041 PMCID: PMC3601012 DOI: 10.1186/1297-9716-44-15] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2012] [Accepted: 02/07/2013] [Indexed: 11/18/2022] Open
Abstract
Chagas disease has a high incidence in Mexico and other Latin American countries. Because one of the most important known methods of prevention is vector control, which has been effective only in certain areas of South America, the development of a vaccine to protect people at risk has been proposed. In this study, we assessed the cellular and humoral immune response generated following immunization with pBCSP and pBCSSP4 plasmids containing the genes encoding a trans-sialidase protein (present in all three forms of T. cruzi) and an amastigote specific glycoprotein, respectively, in a canine model. Thirty-five beagle dogs were divided randomly into 5 groups (n = 7) and were immunized twice intramuscularly with 500 μg of pBCSSP4, pBCSP, pBk-CMV (empty plasmid) or saline solution. Fifteen days after the last immunization the 4 groups were infected intraperitoneally with 500 000 metacyclic trypomastigotes. The fifth group was unimmunized/infected. The parasitaemia in the immunized/infected dogs was for a shorter period (14 vs. 29 days) and the parasite load was lower. The concentration of IgG1 (0.612 ± 0.019 O.D.) and IgG2 (1.167 ± 0.097 O.D.) subclasses was measured (absorbance) 15 days after the last immunization with both recombinant plasmids, the majority of which were IgG2. The treatment of parasites using the serum from dogs immunized with pBCSP and pBCSSP4 plasmids produced 54% (± 11.8) and 68% (± 21.4) complement-mediated lysis, respectively. At 12 h post immunization, an increase in cytokines was not observed; however, vaccination with pBCSSP4 significantly increased the levels of IFN-γ and IL-10 at 9 months post-infection. The recombinant plasmid immunization stimulated the spleen cell proliferation showing a positive stimulatory index above 2.0. In conclusion, immunization using both genes effectively induces a humoral and cellular immune response.
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Affiliation(s)
- Minerva Arce-Fonseca
- Department of Molecular Biology, Instituto Nacional de Cardiología "Ignacio Chávez", Juan Badiano No, 1, Col, Sección XVI, Tlalpan, Mexico City, CP 14080, Mexico.
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Basso B. Modulation of immune response in experimental Chagas disease. World J Exp Med 2013; 3:1-10. [PMID: 24520540 PMCID: PMC3905588 DOI: 10.5493/wjem.v3.i1.1] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2012] [Revised: 01/07/2013] [Accepted: 02/06/2013] [Indexed: 02/06/2023] Open
Abstract
Trypanosoma cruzi (T. cruzi), the etiological agent of Chagas disease, affects nearly 18 million people in Latin America and 90 million are at risk of infection. The parasite presents two stages of medical importance in the host, the amastigote, intracellular replicating form, and the extracellular trypomastigote, the infective form. Thus infection by T. cruzi induces a complex immune response that involves effectors and regulatory mechanisms. That is why control of the infection requires a strong humoral and cellular immune response; hence, the outcome of host-parasite interaction in the early stages of infection is extremely important. A critical event during this period of the infection is innate immune response, in which the macrophage’s role is vital. Thus, after being phagocytized, the parasite is able to develop intracellularly; however, during later periods, these cells induce its elimination by means of toxic metabolites. In turn, as the infection progresses, adaptive immune response mechanisms are triggered through the TH1 and TH2 responses. Finally, T. cruzi, like other protozoa such as Leishmania and Toxoplasma, have numerous evasive mechanisms to the immune response that make it possible to spread around the host. In our Laboratory we have developed a vaccination model in mice with Trypanosoma rangeli, nonpathogenic to humans, which modulates the immune response to infection by T. cruzi, thus protecting them. Vaccinated animals showed an important innate response (modulation of NO and other metabolites, cytokines, activation of macrophages), a strong adaptive cellular response and significant increase in specific antibodies. The modulation caused early elimination of the parasites, low parasitaemia, the absence of histological lesions and high survival rates. Even though progress has been made in the knowledge of some of these mechanisms, new studies must be conducted which could target further prophylactic and therapeutic trials against T. cruzi infection.
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Different infective forms trigger distinct immune response in experimental Chagas disease. PLoS One 2012; 7:e32912. [PMID: 22412949 PMCID: PMC3296760 DOI: 10.1371/journal.pone.0032912] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2011] [Accepted: 02/04/2012] [Indexed: 11/26/2022] Open
Abstract
Although metacyclic and blood trypomastigotes are completely functional in relation to parasite-host interaction and/or target cell invasion, they differ in the molecules present on the surface. Thus, aspects related to the variability that the forms of T. cruzi interacts with host cells may lead to fundamental implications on the immune response against this parasite and, consequently, the clinical evolution of Chagas disease. We have shown that BT infected mice presented higher levels of parasitemia during all the acute phase of infection. Moreover, the infection with either MT or BT forms resulted in increased levels of total leukocytes, monocytes and lymphocytes, specifically later for MT and earlier for BT. The infection with BT forms presented earlier production of proinflammatory cytokine TNF-α and later of IFN-γ by both T cells subpopulations. This event was accompanied by an early cardiac inflammation with an exacerbation of this process at the end of the acute phase. On the other hand, infection with MT forms result in an early production of IFN-γ, with subsequent control in the production of this cytokine by IL-10, which provided to these animals an immunomodulatory profile in the end of the acute phase. These results are in agreement with what was found for cardiac inflammation where animals infected with MT forms showed intense cardiac inflammation later at infection, with a decrease in the same at the end of this phase. In summary, our findings emphasize the importance of taking into account the inoculums source of T. cruzi, since vectorial or transfusional routes of T. cruzi infection may trigger distinct parasite-host interactions during the acute phase that may influence relevant biological aspects of chronic Chagas disease.
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Marini V, Moretti E, Bermejo D, Basso B. Vaccination with Trypanosoma rangeli modulates the profiles of immunoglobulins and IL-6 at local and systemic levels in the early phase of Trypanosoma cruzi experimental infection. Mem Inst Oswaldo Cruz 2011; 106:32-7. [PMID: 21340352 DOI: 10.1590/s0074-02762011000100005] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2010] [Accepted: 12/08/2010] [Indexed: 12/17/2022] Open
Abstract
In America, there are two species of Trypanosoma that can infect humans: Trypanosoma cruzi, which is responsible for Chagas disease and Trypanosoma rangeli, which is not pathogenic. We have developed a model of vaccination in mice with T. rangeli epimastigotes that protects against T. cruzi infection. The goal of this work was to study the pattern of specific immunoglobulins in the peritoneum (the site of infection) and in the sera of mice immunized with T. rangeli before and after challenge with T. cruzi. Additionally, we studied the effects triggered by antigen-antibodies binding and the levels of key cytokines involved in the humoral response, such as IL-4, IL-5 and IL-6. The immunization triggered the production of antibodies reactive with T. cruzi in peritoneal fluid (PF) and in serum, mainly IgG1 and, to a lesser magnitude, IgG2. Only immunized mice developed specific IgG3 antibodies in their peritoneal cavities. Antibodies were able to bind to the surface of the parasites and agglutinate them. Among the cytokines studied, IL-6 was elevated in PF during early infection, with higher levels in non-immunized-infected mice. The results indicate that T. rangeli vaccination against T. cruzi infection triggers a high production of specific IgG isotypes in PF and sera before infection and modulates the levels of IL-6 in PF in the early periods of infection.
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Affiliation(s)
- Vanina Marini
- Laboratorio de la Coordinación Nacional de Control de Vectores, Córdoba, Argentina
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Aparicio-Burgos JE, Ochoa-García L, Zepeda-Escobar JA, Gupta S, Dhiman M, Martínez JS, de Oca-Jiménez RM, Arreola MV, Barbabosa-Pliego A, Vázquez-Chagoyán JC, Garg NJ. Testing the efficacy of a multi-component DNA-prime/DNA-boost vaccine against Trypanosoma cruzi infection in dogs. PLoS Negl Trop Dis 2011; 5:e1050. [PMID: 21625470 PMCID: PMC3098890 DOI: 10.1371/journal.pntd.0001050] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2010] [Accepted: 04/15/2011] [Indexed: 11/19/2022] Open
Abstract
Background Trypanosoma cruzi, the etiologic agent of Chagas Disease, is
a major vector borne health problem in Latin America and an emerging
infectious disease in the United States. Methods We tested the efficacy of a multi-component DNA-prime/DNA-boost vaccine
(TcVac1) against experimental T. cruzi infection in a
canine model. Dogs were immunized with antigen-encoding plasmids and
cytokine adjuvants, and two weeks after the last immunization, challenged
with T. cruzi trypomastigotes. We measured antibody
responses by ELISA and haemagglutination assay, parasitemia and infectivity
to triatomines by xenodiagnosis, and performed electrocardiography and
histology to assess myocardial damage and tissue pathology. Results Vaccination with TcVac1 elicited parasite-and antigen-specific IgM and IgG
(IgG2>IgG1) responses. Upon challenge infection, TcVac1-vaccinated dogs,
as compared to non-vaccinated controls dogs, responded to T.
cruzi with a rapid expansion of antibody response, moderately
enhanced CD8+ T cell proliferation and IFN-γ production,
and suppression of phagocytes’ activity evidenced by decreased
myeloperoxidase and nitrite levels. Subsequently, vaccinated dogs controlled
the acute parasitemia by day 37 pi (44 dpi in non-vaccinated dogs), and
exhibited a moderate decline in infectivity to triatomines. TcVac1-immunized
dogs did not control the myocardial parasite burden and electrocardiographic
and histopatholgic cardiac alterations that are the hallmarks of acute
Chagas disease. During the chronic stage, TcVac1-vaccinated dogs exhibited a
moderate decline in cardiac alterations determined by EKG and
anatomo-/histo-pathological analysis while
chronically-infected/non-vaccinated dogs continued to exhibit severe EKG
alterations. Conclusions Overall, these results demonstrated that TcVac1 provided a partial resistance
to T. cruzi infection and Chagas disease, and provide an
impetus to improve the vaccination strategy against Chagas disease. Immunization of dogs with DNA-prime/DNA-boost vaccine (TcVac1) enhanced the
Trypanosoma cruzi-specific type 1 antibody and
CD8+ T cell responses that resulted in an early control of
acute parasitemia and a moderate decline in pathological symptoms during chronic
phase. Further improvement of vaccine-induced immunity would be required to
achieve clinical and epidemiological benefits and prevent transmission of
parasites from vaccinated/infected dogs to triatomines.
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Affiliation(s)
- José E. Aparicio-Burgos
- Centro de Investigación y Estudios
Avanzados, Universidad Autónoma de Estado de México, Toluca,
México
| | - Laucel Ochoa-García
- Centro de Investigación y Estudios
Avanzados, Universidad Autónoma de Estado de México, Toluca,
México
| | | | - Shivali Gupta
- Department of Microbiology and Immunology,
University of Texas Medical Branch, Galveston, Texas, United States of
America
| | - Monisha Dhiman
- Department of Microbiology and Immunology,
University of Texas Medical Branch, Galveston, Texas, United States of
America
| | - José Simón Martínez
- Centro de Investigación y Estudios
Avanzados, Universidad Autónoma de Estado de México, Toluca,
México
| | | | | | - Alberto Barbabosa-Pliego
- Centro de Investigación y Estudios
Avanzados, Universidad Autónoma de Estado de México, Toluca,
México
| | - Juan C. Vázquez-Chagoyán
- Centro de Investigación y Estudios
Avanzados, Universidad Autónoma de Estado de México, Toluca,
México
- * E-mail: (NJG); (JCV-C)
| | - Nisha Jain Garg
- Department of Microbiology and Immunology,
University of Texas Medical Branch, Galveston, Texas, United States of
America
- Department of Pathology, University of Texas
Medical Branch, Galveston, Texas, United States of America
- Faculty of the Institute for Human Infections
and Immunity, and the Sealy Center for Vaccine Development, University of Texas
Medical Branch, Galveston, Texas, United States of America
- * E-mail: (NJG); (JCV-C)
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IgE mediates killing of intracellular Toxoplasma gondii by human macrophages through CD23-dependent, interleukin-10 sensitive pathway. PLoS One 2011; 6:e18289. [PMID: 21526166 PMCID: PMC3081288 DOI: 10.1371/journal.pone.0018289] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2010] [Accepted: 03/02/2011] [Indexed: 12/24/2022] Open
Abstract
Background In addition to helminthic infections, elevated serum IgE levels were observed in many protozoal infections, while their contribution during immune response to these pathogens remained unclear. As IgE/antigen immune complexes (IgE-IC) bind to human cells through FcεRI or FcεRII/CD23 surface molecules, the present study aimed to identify which functional receptor may be involved in IgE-IC interaction with human macrophages, the major effector cell during parasite infection. Methodology/Principal Findings Human monocyte-derived macrophages were infected with Toxoplasma gondii before being incubated with IgE-IC. IgE receptors were then identified using appropriate blocking antibodies. The activation of cells and parasiticidal activity were evaluated by mediator quantification and direct counting of infected macrophages. RNAs were extracted and cell supernatants were also collected for their content in tumor necrosis factor (TNF)-α, interleukin-10 (IL-10) and nitrites. Sera from symptomatic infected patients were also tested for their content of IgE, IL-10 and nitrites, and compared to values found in healthy donors. Results showed that IgE-IC induced intracellular elimination of parasites by human macrophages. IgE-mediated effect was FcεRI-independent, but required cross-linking of surface FcεRII/CD23, cell activation and the generation of nitric oxide (NO). Although TNF-α was shown to be produced during cell activation, this cytokine had minor contribution in this phenomenon while endogenous and exogenous IL-10 down-regulated parasite killing. Inverse relationship was found between IL-10 and NO expression by infected human macrophages at both mRNA and mediator levels. The relationship between these in vitro data and in vivo levels of various factors in T. gondii infected patients supports the involvement of CD23 antigen and IL-10 expression in disease control. Conclusion Thus, IgE may be considered as immune mediator during antiprotozoal activity of human macrophages through its ability to trigger CD23 signaling. Increased cell activation by IgE-IC may also account for chronic inflammatory diseases observed in some patients.
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