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Perumal N, White B, Sanchez-Valdez F, Tarleton RL. cGAS-STING Pathway Activation during Trypanosoma cruzi Infection Leads to Tissue-Dependent Parasite Control. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2023; 211:1123-1133. [PMID: 37603014 PMCID: PMC10783805 DOI: 10.4049/jimmunol.2300373] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Accepted: 07/31/2023] [Indexed: 08/22/2023]
Abstract
Host cell invasion by Trypanosoma cruzi is a markedly silent process, with limited host transcriptional changes indicative of innate immune recognition, except for a modest type I IFN (IFN-I) response. In this study, we show that T. cruzi-induced IFN-β production was nearly abolished in primary murine cGAS-/- or stimulator of IFN genes (STING)-deficient (STINGGt) macrophages and fibroblasts. T. cruzi infection did not impact the ability of IFN-regulatory factor reporter macrophages to respond to classical cGAS-STING agonists, indicating that the limited IFN-β induction is not due to active parasite suppression. cGAS-/-, STINGGt, and IFN-α/β receptor-/- (IFNAR-/-) macrophages infected with T. cruzi yielded significantly higher numbers of amastigotes compared with wild-type macrophages; however, the impact of the STING pathway during infection in vivo is more complex. Despite an initial increase in parasite growth, STINGGt and IFNAR-/- mice ultimately had lower parasite burden in footpads as compared with wild-type mice, demonstrating a role for IFN-I expression in potentiating parasite growth at the infection site. STING pathway activation had little impact on parasite levels in the skeletal muscle; however, in the heart, cGAS-/- and STINGGt mice, but not IFNAR-/- mice, accumulated higher acute parasite loads, suggesting a protective role of STING sensing of T. cruzi in this organ that was independent of IFN-I. Together, these results demonstrate that host cGAS-STING senses T. cruzi infection, enhancing parasite growth at the site of entry, and contributes to acute-phase parasite restriction in the heart, a major site of tissue damage in chronic T. cruzi infection.
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Affiliation(s)
- Natasha Perumal
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA
- Department of Cellular Biology, University of Georgia, Athens, GA
| | - Brooke White
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA
| | | | - Rick L Tarleton
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA
- Department of Cellular Biology, University of Georgia, Athens, GA
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2
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Tarleton RL. Effective drug discovery in Chagas disease. Trends Parasitol 2023; 39:423-431. [PMID: 37024318 DOI: 10.1016/j.pt.2023.03.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Revised: 03/17/2023] [Accepted: 03/17/2023] [Indexed: 04/07/2023]
Abstract
The Chagas field has gone >50 years without tangible progress toward new therapies. My colleagues and I have recently reported on a benzoxaborole compound that achieves consistent parasitological cure in experimentally infected mice and in naturally infected non-human primates (NHPs). While these results do not assure success in human clinical trials, they significantly de-risk this process and form a strong justification for such trials. Highly effective drug discovery depends on a solid understanding of host and parasite biology and excellent knowledge in designing and validating chemical entities. This opinion piece seeks to provide perspectives on the process that led to the discovery of AN15368, with the hope that this will facilitate the discovery of additional clinical candidates for Chagas disease.
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Affiliation(s)
- Rick L Tarleton
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA 30602, USA.
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3
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Recent Advances in the Development of Adenovirus-Vectored Vaccines for Parasitic Infections. Pharmaceuticals (Basel) 2023; 16:ph16030334. [PMID: 36986434 PMCID: PMC10058461 DOI: 10.3390/ph16030334] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2023] [Revised: 01/30/2023] [Accepted: 02/09/2023] [Indexed: 02/24/2023] Open
Abstract
Vaccines against parasites have lagged centuries behind those against viral and bacterial infections, despite the devastating morbidity and widespread effects of parasitic diseases across the globe. One of the greatest hurdles to parasite vaccine development has been the lack of vaccine strategies able to elicit the complex and multifaceted immune responses needed to abrogate parasitic persistence. Viral vectors, especially adenovirus (AdV) vectors, have emerged as a potential solution for complex disease targets, including HIV, tuberculosis, and parasitic diseases, to name a few. AdVs are highly immunogenic and are uniquely able to drive CD8+ T cell responses, which are known to be correlates of immunity in infections with most protozoan and some helminthic parasites. This review presents recent developments in AdV-vectored vaccines targeting five major human parasitic diseases: malaria, Chagas disease, schistosomiasis, leishmaniasis, and toxoplasmosis. Many AdV-vectored vaccines have been developed for these diseases, utilizing a wide variety of vectors, antigens, and modes of delivery. AdV-vectored vaccines are a promising approach for the historically challenging target of human parasitic diseases.
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Padilla AM, Rosenberg C, Cook P, Sanchez-Valdez F, McElhannon C, Tarleton RL. Delayed Activation of T Cells at the Site of Infection Facilitates the Establishment of Trypanosoma cruzi in Both Naive and Immune Hosts. mSphere 2023; 8:e0060122. [PMID: 36695605 PMCID: PMC9942555 DOI: 10.1128/msphere.00601-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Accepted: 12/16/2022] [Indexed: 01/26/2023] Open
Abstract
Although parasite entry through breaks in the skin or mucosa is one of the main routes of natural transmission of Trypanosoma cruzi, little is known about the host cell types initially invaded nor the ability of those host cells to initiate immune responses at the site of infection. To gain insights into these early events, we studied the fate of fluorescently tagged T. cruzi delivered subcutaneously in mouse footpads or ears. We demonstrate that the majority of parasites introduced into the skin initially proliferate there until 8 to 10 days postinfection, when the parasite load decreases. This decline in parasite numbers is dependent on the presence of an intact T cell compartment and on the ability of hosts to produce gamma interferon (IFN-γ). Many of the parasite-containing cells at the initial infection site display a macrophage/monocyte phenotype but with low expression of activation markers, suggesting that these cells provide an early niche for T. cruzi proliferation, rather than being active in parasite control. It is only after the first round of T. cruzi replication and release from host cells that signs of immune activation and control of parasites become apparent. The delay in the activation and failure to rapidly control parasite replication are observed even when T. cruzi-primed T cells are present, such as in chronically infected mice. This failure of a primed immune system to recognize and react prior to extensive parasite expansion at the infection site likely poses a significant challenge for the development of vaccines aiming to prevent T. cruzi infection. IMPORTANCE Trypanosoma cruzi, the parasite causing Chagas disease, usually infects through the mucosa or breaks in the skin, but little is known about the parasite's fate at the site of entry or the early events involving immune control there. Here, we track the local proliferation and subsequent dissemination of fluorescently tagged T. cruzi and the initial immune response at the point of entry. We show that T. cruzi preferentially infects innate immune cells in the skin and that the stimulation of an adaptive T cell response does not occur until after the release of parasites from this first round of infected host cells. This first immunologically "silent" proliferation occurs even in the presence of a strong immune T cell memory generated by previous infection. This capacity of T. cruzi to establish infections while avoiding initial immune recognition has important implications for the potential to develop vaccines to prevent T. cruzi infection.
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Affiliation(s)
- Angel M. Padilla
- Department of Cellular Biology, University of Georgia, Athens, Georgia, USA
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA
| | - Charles Rosenberg
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA
- Department of Microbiology, University of Georgia, Athens, Georgia, USA
| | - Peter Cook
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, United Kingdom
| | - Fernando Sanchez-Valdez
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA
| | - Caroline McElhannon
- Department of Cellular Biology, University of Georgia, Athens, Georgia, USA
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA
| | - Rick L. Tarleton
- Department of Cellular Biology, University of Georgia, Athens, Georgia, USA
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA
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Biscari L, Maza MC, Farré C, Kaufman CD, Amigorena S, Fresno M, Gironès N, Alloatti A. Sec22b-dependent antigen cross-presentation is a significant contributor of T cell priming during infection with the parasite Trypanosoma cruzi. Front Cell Dev Biol 2023; 11:1138571. [PMID: 36936692 PMCID: PMC10014565 DOI: 10.3389/fcell.2023.1138571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Accepted: 02/17/2023] [Indexed: 03/05/2023] Open
Abstract
Antigen cross-presentation is a vital mechanism of dendritic cells and other antigen presenting cells to orchestrate the priming of cytotoxic responses towards killing of infected or cancer cells. In this process, exogenous antigens are internalized by dendritic cells, processed, loaded onto MHC class I molecules and presented to CD8+ T cells to activate them. Sec22b is an ER-Golgi Intermediate Compartment resident SNARE protein that, in partnership with sintaxin4, coordinates the recruitment of the transporter associated with antigen processing protein and the peptide loading complex to phagosomes, where antigenic peptides that have been proteolyzed in the cytosol are loaded in MHC class I molecules and transported to the cell membrane. The silencing of Sec22b in dendritic cells primary cultures and conditionally in dendritic cells of C57BL/6 mice, critically impairs antigen cross-presentation, but neither affects other antigen presentation routes nor cytokine production and secretion. Mice with Sec22b conditionally silenced in dendritic cells (Sec22b-/-) show deficient priming of CD8+ T lymphocytes, fail to control tumor growth, and are resistant to anti-checkpoint immunotherapy. In this work, we show that Sec22b-/- mice elicit a deficient specific CD8+ T cell response when challenged with sublethal doses of Trypanosoma cruzi trypomastigotes that is associated with increased blood parasitemia and diminished survival.
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Affiliation(s)
- Lucía Biscari
- Instituto de Inmunología Clínica y Experimental de Rosario (IDICER), CONICET, Universidad Nacional de Rosario, Rosario, Argentina
| | - Ma Carmen Maza
- Departamento de Biología Molecular, Universidad Autónoma de Madrid (UAM), Madrid, Spain
- Centro de Biología Molecular Severo Ochoa (CSIC-UAM), Madrid, Spain
| | - Cecilia Farré
- Instituto de Inmunología Clínica y Experimental de Rosario (IDICER), CONICET, Universidad Nacional de Rosario, Rosario, Argentina
- Centro de Investigación y Producción de Reactivos Biológicos, Facultad de Ciencias Médicas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Cintia Daniela Kaufman
- Instituto de Inmunología Clínica y Experimental de Rosario (IDICER), CONICET, Universidad Nacional de Rosario, Rosario, Argentina
| | - Sebastian Amigorena
- Institut Curie, INSERM U932, Immunity and Cancer, PSL University, Paris, France
| | - Manuel Fresno
- Departamento de Biología Molecular, Universidad Autónoma de Madrid (UAM), Madrid, Spain
- Centro de Biología Molecular Severo Ochoa (CSIC-UAM), Madrid, Spain
- Instituto de Investigación Sanitaria del Hospital Universitario de la Princesa, Madrid, Spain
| | - Núria Gironès
- Departamento de Biología Molecular, Universidad Autónoma de Madrid (UAM), Madrid, Spain
- Centro de Biología Molecular Severo Ochoa (CSIC-UAM), Madrid, Spain
- Instituto de Investigación Sanitaria del Hospital Universitario de la Princesa, Madrid, Spain
| | - Andrés Alloatti
- Instituto de Inmunología Clínica y Experimental de Rosario (IDICER), CONICET, Universidad Nacional de Rosario, Rosario, Argentina
- *Correspondence: Andrés Alloatti,
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Borgna E, Prochetto E, Gamba JC, Marcipar I, Cabrera G. Role of myeloid-derived suppressor cells during Trypanosoma cruzi infection. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2023; 375:117-163. [PMID: 36967151 DOI: 10.1016/bs.ircmb.2022.09.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Chagas disease (CD), caused by the protozoan parasite Trypanosoma cruzi, is the third largest parasitic disease burden globally. Currently, more than 6 million people are infected, mainly in Latin America, but international migration has turned CD into an emerging health problem in many nonendemic countries. Despite intense research, a vaccine is still not available. A complex parasite life cycle, together with numerous immune system manipulation strategies, may account for the lack of a prophylactic or therapeutic vaccine. There is substantial experimental evidence supporting that T. cruzi acute infection generates a strong immunosuppression state that involves numerous immune populations with regulatory/suppressive capacity. Myeloid-derived suppressor cells (MDSCs), Foxp3+ regulatory T cells (Tregs), regulatory dendritic cells and B regulatory cells are some of the regulatory populations that have been involved in the acute immune response elicited by the parasite. The fact that, during acute infection, MDSCs increase notably in several organs, such as spleen, liver and heart, together with the observation that depletion of those cells can decrease mouse survival to 0%, strongly suggests that MDSCs play a major role during acute T. cruzi infection. Accumulating evidence gained in different settings supports the capacity of MDSCs to interact with cells from both the effector and the regulatory arms of the immune system, shaping the outcome of the response in a very wide range of scenarios that include pathological and physiological processes. In this sense, the aim of the present review is to describe the main knowledge about MDSCs acquired so far, including several crosstalk with other immune populations, which could be useful to gain insight into their role during T. cruzi infection.
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Biscari L, Kaufman CD, Farré C, Huhn V, Pacini MF, Balbi CB, Gómez KA, Pérez AR, Alloatti A. Immunization With Lipopolysaccharide-Activated Dendritic Cells Generates a Specific CD8+ T Cell Response That Confers Partial Protection Against Infection With Trypanosoma cruzi. Front Cell Infect Microbiol 2022; 12:897133. [PMID: 35903201 PMCID: PMC9318436 DOI: 10.3389/fcimb.2022.897133] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Accepted: 06/17/2022] [Indexed: 11/13/2022] Open
Abstract
Lipopolysaccharide (LPS) induces the activation of dendritic cells (DCs) throughout the engagement of toll-like receptor 4. LPS-activated DCs show increased capacity to process and present pathogen-derived antigens to activate naïve T cells. DCs-based vaccines have been successfully used to treat some cancer types, and lately transferred to the field of infectious diseases, in particular against HIV. However, there is no vaccine or DC therapy for any parasitic disease that is currently available. The immune response against Trypanosoma cruzi substantially relies on T cells, and both CD4+ and CD8+ T lymphocytes are required to control parasite growth. Here, we develop a vaccination strategy based on DCs derived from bone marrow, activated with LPS and loaded with TsKb20, an immunodominant epitope of the trans-sialidase family of proteins. We extensively characterized the CD8+ T cell response generated after immunization and compared three different readouts: a tetramer staining, ELISpot and Activation-Induced Marker (AIM) assays. To our knowledge, this work shows for the first time a proper set of T cell markers to evaluate specific CD8+ T cell responses in mice. We also show that our immunization scheme confers protection against T. cruzi, augmenting survival and reducing parasite burden in female but not male mice. We conclude that the immunization with LPS-activated DCs has the potential to prime significant CD8+ T cell responses in C57BL/6 mice independently of the sex, but this response will only be effective in female, possibly due to mice sexual dimorphisms in the response generated against T. cruzi.
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Affiliation(s)
- Lucía Biscari
- Instituto de Inmunología Clínica y Experimental de Rosario (IDICER), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional de Rosario, Rosario, Argentina
| | - Cintia Daniela Kaufman
- Instituto de Inmunología Clínica y Experimental de Rosario (IDICER), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional de Rosario, Rosario, Argentina
| | - Cecilia Farré
- Instituto de Inmunología Clínica y Experimental de Rosario (IDICER), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional de Rosario, Rosario, Argentina
- Centro de Investigación y Producción de Reactivos Biológicos, Facultad de Ciencias Médicas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Victoria Huhn
- Instituto de Inmunología Clínica y Experimental de Rosario (IDICER), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional de Rosario, Rosario, Argentina
| | - María Florencia Pacini
- Instituto de Inmunología Clínica y Experimental de Rosario (IDICER), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional de Rosario, Rosario, Argentina
| | - Camila Bulfoni Balbi
- Instituto de Inmunología Clínica y Experimental de Rosario (IDICER), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional de Rosario, Rosario, Argentina
| | - Karina Andrea Gómez
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular Dr. Héctor N. Torres (INGEBI), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Ana Rosa Pérez
- Instituto de Inmunología Clínica y Experimental de Rosario (IDICER), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional de Rosario, Rosario, Argentina
- Centro de Investigación y Producción de Reactivos Biológicos, Facultad de Ciencias Médicas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Andrés Alloatti
- Instituto de Inmunología Clínica y Experimental de Rosario (IDICER), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional de Rosario, Rosario, Argentina
- *Correspondence: Andrés Alloatti,
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Jones KM, Poveda C, Versteeg L, Bottazzi ME, Hotez PJ. Preclinical advances and the immunophysiology of a new therapeutic chagas disease vaccine. Expert Rev Vaccines 2022; 21:1185-1203. [PMID: 35735065 DOI: 10.1080/14760584.2022.2093721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
INTRODUCTION Chronic infection with the protozoal parasite Trypanosoma cruzi leads to a progressive cardiac disease, known as chronic Chagasic cardiomyopathy (CCC). A new therapeutic Chagas disease vaccine is in development to augment existing antiparasitic chemotherapy drugs. AREAS COVERED We report on our current understanding of the underlying immunologic and physiologic mechanisms that lead to CCC, including parasite immune escape mechanisms that allow persistence and the subsequent inflammatory and fibrotic processes that lead to clinical disease. We report on vaccine design and the observed immunotherapeutic effects including induction of a balanced TH1/TH2/TH17 immune response that leads to reduced parasite burdens and tissue pathology. Further, we report vaccine-linked chemotherapy, a dose sparing strategy to further reduce parasite burdens and tissue pathology. EXPERT OPINION Our vaccine-linked chemotherapeutic approach is a multimodal treatment strategy, addressing both the parasite persistence and the underlying deleterious host inflammatory and fibrotic responses that lead to cardiac dysfunction. In targeting treatment towards patients with chronic indeterminate or early determinate Chagas disease, this vaccine-linked chemotherapeutic approach will be highly economical and will reduce the global disease burden and deaths due to CCC.
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Affiliation(s)
- Kathryn M Jones
- Texas Children's Hospital Center for Vaccine Development, Department of Pediatrics, Division of Tropical Medicine, Baylor College of Medicine, Houston, Texas, United States of America.,Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, United States of America
| | - Cristina Poveda
- Texas Children's Hospital Center for Vaccine Development, Department of Pediatrics, Division of Tropical Medicine, Baylor College of Medicine, Houston, Texas, United States of America.,Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, United States of America
| | - Leroy Versteeg
- Texas Children's Hospital Center for Vaccine Development, Department of Pediatrics, Division of Tropical Medicine, Baylor College of Medicine, Houston, Texas, United States of America.,Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, United States of America.,Cell Biology and Immunology Group, Wageningen University & Research, De Elst 1, 6708 WD Wageningen, The Netherlands
| | - Maria Elena Bottazzi
- Texas Children's Hospital Center for Vaccine Development, Department of Pediatrics, Division of Tropical Medicine, Baylor College of Medicine, Houston, Texas, United States of America.,Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, United States of America.,Department of Biology, Baylor University, Waco, Texas, United States of America
| | - Peter J Hotez
- Texas Children's Hospital Center for Vaccine Development, Department of Pediatrics, Division of Tropical Medicine, Baylor College of Medicine, Houston, Texas, United States of America.,Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, United States of America.,Department of Biology, Baylor University, Waco, Texas, United States of America.,James A. Baker III Institute for Public Policy, Rice University, Houston, Texas, United States of America.,Hagler Institute for Advanced Study at Texas A&M University, College Station, Texas, United States of America
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9
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Ward AI, Lewis MD, Taylor MC, Kelly JM. Incomplete Recruitment of Protective T Cells Is Associated with Trypanosoma cruzi Persistence in the Mouse Colon. Infect Immun 2022; 90:e0038221. [PMID: 34780279 PMCID: PMC8853677 DOI: 10.1128/iai.00382-21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Accepted: 11/08/2021] [Indexed: 11/24/2022] Open
Abstract
Trypanosoma cruzi is the etiological agent of Chagas disease. Following T cell-mediated suppression of acute-phase infection, this intracellular eukaryotic pathogen persists long-term in a limited subset of tissues at extremely low levels. The reasons for this tissue-specific chronicity are not understood. Using a dual bioluminescent-fluorescent reporter strain and highly sensitive tissue imaging that allows experimental infections to be monitored at single-cell resolution, we undertook a systematic analysis of the immunological microenvironments of rare parasitized cells in the mouse colon, a key site of persistence. We demonstrate that incomplete recruitment of T cells to a subset of colonic infection foci permits the occurrence of repeated cycles of intracellular parasite replication and differentiation to motile trypomastigotes at a frequency sufficient to perpetuate chronic infections. The lifelong persistence of parasites in this tissue site continues despite the presence, at a systemic level, of a highly effective T cell response. Overcoming this low-level dynamic host-parasite equilibrium represents a major challenge for vaccine development.
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Affiliation(s)
- Alexander I. Ward
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Michael D. Lewis
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Martin C. Taylor
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - John M. Kelly
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
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10
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Chowdhury IH, Lokugamage N, Garg NJ. Experimental Nanovaccine Offers Protection Against Repeat Exposures to Trypanosoma cruzi Through Activation of Polyfunctional T Cell Response. Front Immunol 2020; 11:595039. [PMID: 33414785 PMCID: PMC7783422 DOI: 10.3389/fimmu.2020.595039] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Accepted: 11/19/2020] [Indexed: 10/26/2022] Open
Abstract
A parasitic protozoan Trypanosoma cruzi (T. cruzi) is the etiologic agent of Chagas disease. Previously, we have identified T. cruzi antigens TcG2 and TcG4 as potential vaccine candidates, cloned in eukaryotic expression vector pCDNA3.1 (referred as p2/4) and tested their ability to elicit protection from T. cruzi infection. In the present study, we subcloned the two antigens in a nanoplasmid that is optimized for delivery, antigen expression, and regulatory compliance standards, and evaluated the nanovaccine (referred as nano2/4) for prophylactic protection against repeat T. cruzi infections. For this, C57BL/6 mice were immunized with two doses of p2/4 or nano2/4 at 21 days interval, challenged with T. cruzi 21 days after 2nd immunization, and euthanized at 10- and 21-days post-infection (pi) corresponding to parasite dissemination and replication phase, respectively. Some mice were re-challenged 21 days pi and monitored at 7 days after re-infection. Without the help of a vaccine, T. cruzi elicited delayed and sub-par T cell activation and low levels of effector molecules that failed to control tissue dissemination and replication of the parasite and provided no protection against repeat challenge infection. The nano2/4 was most effective in eliciting an early activation and production of IFN-γ by CD4+T effector/effector memory (TEM) cells and cytolytic perforin (PFN) and granzyme B (GZB) molecules by CD4+ and CD8+ TEM subsets at 10 days pi that was followed by robust expansion of CD4+ and CD8+ TEM and TCM cells with further increase in IFN-γ production at 21 days pi. Consequently, nano2/4-immunized mice exhibited potent control of parasite dissemination at 10 days pi, and tissue parasite burden and tissue inflammatory infiltrate and necrosis were barely detectable at 21 days pi. Furthermore, nano2/4-immunized mice responded to re-challenge infection with high levels of effector molecules production by CD4+ and CD8+ TEM subpopulations that offered even better control of tissue parasite burden than was observed after 1st infection. In comparison, non-vaccinated/infected mice exhibited clinical features of sickness and 59% mortality within 7 days after re-infection. In conclusion, we show that delivery of TcG2 and TcG4 in nanoplasmid offers excellent, protective T cell immunity against repeat T. cruzi infections.
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Affiliation(s)
- Imran H Chowdhury
- Department of Microbiology and Immunology, The University of Texas Medical Branch (UTMB), Galveston, TX, United States
| | - Nandadeva Lokugamage
- Department of Microbiology and Immunology, The University of Texas Medical Branch (UTMB), Galveston, TX, United States
| | - Nisha Jain Garg
- Department of Microbiology and Immunology, The University of Texas Medical Branch (UTMB), Galveston, TX, United States.,Institute for Human Infections and Immunity, UTMB, Galveston, TX, United States
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11
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Pérez-Mazliah D, Ward AI, Lewis MD. Host-parasite dynamics in Chagas disease from systemic to hyper-local scales. Parasite Immunol 2020; 43:e12786. [PMID: 32799361 DOI: 10.1111/pim.12786] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Revised: 08/11/2020] [Accepted: 08/13/2020] [Indexed: 12/14/2022]
Abstract
Trypanosoma cruzi is a remarkably versatile parasite. It can parasitize almost any nucleated cell type and naturally infects hundreds of mammal species across much of the Americas. In humans, it is the cause of Chagas disease, a set of mainly chronic conditions predominantly affecting the heart and gastrointestinal tract, which can progress to become life threatening. Yet around two thirds of infected people are long-term asymptomatic carriers. Clinical outcomes depend on many factors, but the central determinant is the nature of the host-parasite interactions that play out over the years of chronic infection in diverse tissue environments. In this review, we aim to integrate recent developments in the understanding of the spatial and temporal dynamics of T. cruzi infections with established and emerging concepts in host immune responses in the corresponding phases and tissues.
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Affiliation(s)
- Damián Pérez-Mazliah
- York Biomedical Research Institute, Hull York Medical School, University of York, York, UK
| | - Alexander I Ward
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | - Michael D Lewis
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
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Antonoglou MB, Sánchez Alberti A, Redolfi DM, Bivona AE, Fernández Lynch MJ, Noli Truant S, Sarratea MB, Iannantuono López LV, Malchiodi EL, Fernández MM. Heterologous Chimeric Construct Comprising a Modified Bacterial Superantigen and a Cruzipain Domain Confers Protection Against Trypanosoma cruzi Infection. Front Immunol 2020; 11:1279. [PMID: 32695105 PMCID: PMC7338481 DOI: 10.3389/fimmu.2020.01279] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 05/20/2020] [Indexed: 01/18/2023] Open
Abstract
Chagas disease is an endemic chronic parasitosis in Latin America affecting more than 7 million people. Around 100 million people are currently at risk of acquiring the infection; however, no effective vaccine has been developed yet. Trypanosoma cruzi is the etiological agent of this parasitosis and as an intracellular protozoan it can reside within different tissues, mainly muscle cells, evading host immunity and allowing progression towards the chronic stage of the disease. Considering this intracellular parasitism triggers strong cellular immunity that, besides being necessary to limit infection, is not sufficient to eradicate the parasite from tissues, a differential immune response is required and new strategies for vaccines against Chagas disease need to be explored. In this work, we designed, cloned and expressed a chimeric molecule, named NCz-SEGN24A, comprising a parasite antigen, the N-terminal domain of the major cysteine protease of T. cruzi, cruzipain (Nt-Cz), and a non-toxic form of the staphylococcal superantigen (SAg) G, SEG, with the residue Asn24 mutated to Ala (N24A). The mutant SAg SEGN24A, retains its ability to trigger classical activation of macrophages without inducing T cell apoptosis. To evaluate, as a proof of concept, the immunogenicity and efficacy of the chimeric immunogen vs. its individual antigens, C3H mice were immunized intramuscularly with NCz-SEGN24A co-adjuvanted with CpG-ODN, or the recombinant proteins Nt-Cz plus SEGN24A with the same adjuvant. Vaccinated mice significantly produced Nt-Cz-specific IgG titers after immunization and developed higher IgG2a than IgG1 titers. Specific cell-mediated immunity was assessed by in-vivo DTH and significant responses were obtained. To assess protection, mice were challenged with trypomastigotes of T. cruzi. Both schemes reduced the parasite load throughout the acute phase, but only mice immunized with NCz-SEGN24A showed significant differences against control; moreover, these mice maintained 100% survival. These results encourage testing mutated superantigens fused to specific antigens as immune modulators against pathogens.
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Affiliation(s)
- María Belén Antonoglou
- Cátedra de Inmunología, Departamento de Microbiología, Inmunología, Biotecnología y Genética, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina.,Instituto de Estudios de la Inmunidad Humoral "Prof. Ricardo A. Margni" (IDEHU), UBA-CONICET, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Andrés Sánchez Alberti
- Cátedra de Inmunología, Departamento de Microbiología, Inmunología, Biotecnología y Genética, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina.,Instituto de Estudios de la Inmunidad Humoral "Prof. Ricardo A. Margni" (IDEHU), UBA-CONICET, Universidad de Buenos Aires, Buenos Aires, Argentina.,Departamento de Microbiología, Parasitología e Inmunología, Facultad de Medicina and Instituto de Microbiología y Parasitología Médica (IMPaM), UBA-CONICET, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Daniela María Redolfi
- Cátedra de Inmunología, Departamento de Microbiología, Inmunología, Biotecnología y Genética, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina.,Instituto de Estudios de la Inmunidad Humoral "Prof. Ricardo A. Margni" (IDEHU), UBA-CONICET, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Augusto Ernesto Bivona
- Cátedra de Inmunología, Departamento de Microbiología, Inmunología, Biotecnología y Genética, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina.,Instituto de Estudios de la Inmunidad Humoral "Prof. Ricardo A. Margni" (IDEHU), UBA-CONICET, Universidad de Buenos Aires, Buenos Aires, Argentina.,Departamento de Microbiología, Parasitología e Inmunología, Facultad de Medicina and Instituto de Microbiología y Parasitología Médica (IMPaM), UBA-CONICET, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - María Julieta Fernández Lynch
- Cátedra de Inmunología, Departamento de Microbiología, Inmunología, Biotecnología y Genética, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina.,Instituto de Estudios de la Inmunidad Humoral "Prof. Ricardo A. Margni" (IDEHU), UBA-CONICET, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Sofía Noli Truant
- Cátedra de Inmunología, Departamento de Microbiología, Inmunología, Biotecnología y Genética, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina.,Instituto de Estudios de la Inmunidad Humoral "Prof. Ricardo A. Margni" (IDEHU), UBA-CONICET, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - María Belén Sarratea
- Cátedra de Inmunología, Departamento de Microbiología, Inmunología, Biotecnología y Genética, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina.,Instituto de Estudios de la Inmunidad Humoral "Prof. Ricardo A. Margni" (IDEHU), UBA-CONICET, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Laura Valeria Iannantuono López
- Instituto de Estudios de la Inmunidad Humoral "Prof. Ricardo A. Margni" (IDEHU), UBA-CONICET, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Emilio Luis Malchiodi
- Cátedra de Inmunología, Departamento de Microbiología, Inmunología, Biotecnología y Genética, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina.,Instituto de Estudios de la Inmunidad Humoral "Prof. Ricardo A. Margni" (IDEHU), UBA-CONICET, Universidad de Buenos Aires, Buenos Aires, Argentina.,Departamento de Microbiología, Parasitología e Inmunología, Facultad de Medicina and Instituto de Microbiología y Parasitología Médica (IMPaM), UBA-CONICET, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Marisa Mariel Fernández
- Cátedra de Inmunología, Departamento de Microbiología, Inmunología, Biotecnología y Genética, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina.,Instituto de Estudios de la Inmunidad Humoral "Prof. Ricardo A. Margni" (IDEHU), UBA-CONICET, Universidad de Buenos Aires, Buenos Aires, Argentina
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Abstract
Monoclonal antibody targeting the CD20 antigen on B cells is used to treat the majority of non-Hodgkin lymphoma patients and some autoimmune disorders. This therapy generates adverse effects, notably opportunistic infections and activation of viruses from latency. Here, using the infection murine model with the intracellular parasite Trypanosoma cruzi, we report that anti-CD20 treatment affects not only B cell responses but also CD8+ T cell responses, representing the most important immune effectors involved in control of intracellular pathogens. Anti-CD20 treatment, directly or indirectly, affects cytotoxic T cell number and function, and this deficient response was rescued by the cytokine IL-17A. The identification of IL-17A as the cytokine capable of reversing the poor response of CD8+ T cells provides information about a potential therapeutic treatment aimed at enhancing defective immunity induced by B cell depletion. Treatment with anti-CD20, used in many diseases in which B cells play a pathogenic role, has been associated with susceptibility to intracellular infections. Here, we studied the effect of anti-CD20 injection on CD8+ T cell immunity using an experimental model of Trypanosoma cruzi infection, in which CD8+ T cells play a pivotal role. C57BL/6 mice were treated with anti-CD20 for B cell depletion prior to T. cruzi infection. Infected anti-CD20-treated mice exhibited a CD8+ T cell response with a conserved expansion phase followed by an early contraction, resulting in a strong reduction in total and parasite-specific CD8+ T cell numbers at 20 days postinfection. Anti-CD20 injection increased the frequency of apoptotic CD8+ T cells, decreased the number of effector and memory CD8+ T cells, and reduced the frequency of proliferating and cytokine-producing CD8+ T cells. Accordingly, infected anti-CD20-treated mice presented lower cytotoxicity of T. cruzi peptide-pulsed target cells in vivo. All of these alterations in CD8+ T cell immunity were associated with increased tissue parasitism. Anti-CD20 injection also dampened the CD8+ T cell response, when this had already been generated, indicating that B cells were involved in the maintenance rather than the induction of CD8+ T cell immunity. Anti-CD20 injection also resulted in a marked reduction in the frequency of interleukin-6 (IL-6)- and IL-17A-producing cells, and recombinant IL-17A (rIL-17A) injection partially restored the CD8+ T cell response in infected anti-CD20-treated mice. Thus, anti-CD20 reduced CD8+ T cell immunity, and IL-17A is a candidate for rescuing deficient responses either directly or indirectly.
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Cerbán FM, Stempin CC, Volpini X, Carrera Silva EA, Gea S, Motran CC. Signaling pathways that regulate Trypanosoma cruzi infection and immune response. Biochim Biophys Acta Mol Basis Dis 2020; 1866:165707. [DOI: 10.1016/j.bbadis.2020.165707] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2019] [Revised: 01/14/2020] [Accepted: 01/22/2020] [Indexed: 02/07/2023]
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Drug-cured experimental Trypanosoma cruzi infections confer long-lasting and cross-strain protection. PLoS Negl Trop Dis 2020; 14:e0007717. [PMID: 32302312 PMCID: PMC7190179 DOI: 10.1371/journal.pntd.0007717] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 04/29/2020] [Accepted: 02/11/2020] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND The long term and complex nature of Chagas disease in humans has restricted studies on vaccine feasibility. Animal models also have limitations due to technical difficulties in monitoring the extremely low parasite burden that is characteristic of chronic stage infections. Advances in imaging technology offer alternative approaches that circumvent these problems. Here, we describe the use of highly sensitive whole body in vivo imaging to assess the efficacy of recombinant viral vector vaccines and benznidazole-cured infections to protect mice from challenge with Trypanosoma cruzi. METHODOLOGY/PRINCIPAL FINDINGS Mice were infected with T. cruzi strains modified to express a red-shifted luciferase reporter. Using bioluminescence imaging, we assessed the degree of immunity to re-infection conferred after benznidazole-cure. Those infected for 14 days or more, prior to the onset of benznidazole treatment, were highly protected from challenge with both homologous and heterologous strains. There was a >99% reduction in parasite burden, with parasites frequently undetectable after homologous challenge. This level of protection was considerably greater than that achieved with recombinant vaccines. It was also independent of the route of infection or size of the challenge inoculum, and was long-lasting, with no significant diminution in immunity after almost a year. When the primary infection was benznidazole-treated after 4 days (before completion of the first cycle of intracellular infection), the degree of protection was much reduced, an outcome associated with a minimal T. cruzi-specific IFN-γ+ T cell response. CONCLUSIONS/SIGNIFICANCE Our findings suggest that a protective Chagas disease vaccine must have the ability to eliminate parasites before they reach organs/tissues, such as the GI tract, where once established, they become largely refractory to the induced immune response.
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Bivona AE, Alberti AS, Cerny N, Trinitario SN, Malchiodi EL. Chagas disease vaccine design: the search for an efficient Trypanosoma cruzi immune-mediated control. Biochim Biophys Acta Mol Basis Dis 2020; 1866:165658. [PMID: 31904415 DOI: 10.1016/j.bbadis.2019.165658] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Accepted: 12/20/2019] [Indexed: 12/21/2022]
Abstract
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.
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Affiliation(s)
- Augusto E Bivona
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Inmunología and Instituto de Estudios de la Inmunidad Humoral Prof. Dr. Ricardo A. Margni (IDEHU), UBA-CONICET, Buenos Aires, Argentina; Universidad de Buenos Aires, Facultad de Medicina, Departamento de Microbiología, Parasitología e Inmunología and Instituto de Microbiología y Parasitología Médica (IMPaM), UBA-CONICET, Buenos Aires, Argentina
| | - Andrés Sánchez Alberti
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Inmunología and Instituto de Estudios de la Inmunidad Humoral Prof. Dr. Ricardo A. Margni (IDEHU), UBA-CONICET, Buenos Aires, Argentina; Universidad de Buenos Aires, Facultad de Medicina, Departamento de Microbiología, Parasitología e Inmunología and Instituto de Microbiología y Parasitología Médica (IMPaM), UBA-CONICET, Buenos Aires, Argentina
| | - Natacha Cerny
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Inmunología and Instituto de Estudios de la Inmunidad Humoral Prof. Dr. Ricardo A. Margni (IDEHU), UBA-CONICET, Buenos Aires, Argentina; Universidad de Buenos Aires, Facultad de Medicina, Departamento de Microbiología, Parasitología e Inmunología and Instituto de Microbiología y Parasitología Médica (IMPaM), UBA-CONICET, Buenos Aires, Argentina
| | - Sebastián N Trinitario
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Inmunología and Instituto de Estudios de la Inmunidad Humoral Prof. Dr. Ricardo A. Margni (IDEHU), UBA-CONICET, Buenos Aires, Argentina; Universidad de Buenos Aires, Facultad de Medicina, Departamento de Microbiología, Parasitología e Inmunología and Instituto de Microbiología y Parasitología Médica (IMPaM), UBA-CONICET, Buenos Aires, Argentina
| | - Emilio L Malchiodi
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Inmunología and Instituto de Estudios de la Inmunidad Humoral Prof. Dr. Ricardo A. Margni (IDEHU), UBA-CONICET, Buenos Aires, Argentina; Universidad de Buenos Aires, Facultad de Medicina, Departamento de Microbiología, Parasitología e Inmunología and Instituto de Microbiología y Parasitología Médica (IMPaM), UBA-CONICET, Buenos Aires, Argentina.
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17
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Acosta Rodríguez EV, Araujo Furlan CL, Fiocca Vernengo F, Montes CL, Gruppi A. Understanding CD8 + T Cell Immunity to Trypanosoma cruzi and How to Improve It. Trends Parasitol 2019; 35:899-917. [PMID: 31607632 PMCID: PMC6815727 DOI: 10.1016/j.pt.2019.08.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Revised: 08/24/2019] [Accepted: 08/26/2019] [Indexed: 12/30/2022]
Abstract
The protozoan Trypanosoma cruzi is the causative agent of Chagas' disease, endemic in Latin America but present worldwide. Research efforts have focused on the examination of immune mechanisms that mediate host protection as well as immunopathology during this parasitic infection. The study of CD8+ T cell immunity emerges as a key aspect given the critical importance of parasite-specific CD8+ T cells for host resistance throughout the infection. In recent years, new research has shed light on novel pathways that modulate the induction, maintenance, and regulation of CD8+ T cell responses to T. cruzi. This new knowledge is setting the ground for future vaccines and/or immunotherapies. Herein, we critically review and analyze the latest results published in the field.
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Affiliation(s)
- Eva V Acosta Rodríguez
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI)-CONICET, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, X5000HUA Córdoba, Argentina.
| | - Cintia L Araujo Furlan
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI)-CONICET, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, X5000HUA Córdoba, Argentina
| | - Facundo Fiocca Vernengo
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI)-CONICET, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, X5000HUA Córdoba, Argentina
| | - Carolina L Montes
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI)-CONICET, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, X5000HUA Córdoba, Argentina
| | - Adriana Gruppi
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI)-CONICET, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, X5000HUA Córdoba, Argentina
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18
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Pack AD, Collins MH, Rosenberg CS, Tarleton RL. Highly competent, non-exhausted CD8+ T cells continue to tightly control pathogen load throughout chronic Trypanosoma cruzi infection. PLoS Pathog 2018; 14:e1007410. [PMID: 30419010 PMCID: PMC6258465 DOI: 10.1371/journal.ppat.1007410] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Revised: 11/26/2018] [Accepted: 10/17/2018] [Indexed: 12/21/2022] Open
Abstract
Trypanosoma cruzi infection is characterized by chronic parasitism of non-lymphoid tissues and is rarely eliminated despite potent adaptive immune responses. This failure to cure has frequently been attributed to a loss or impairment of anti-T. cruzi T cell responses over time, analogous to the T cell dysfunction described for other persistent infections. In this study, we have evaluated the role of CD8+ T cells during chronic T. cruzi infection (>100 dpi), with a focus on sites of pathogen persistence. Consistent with repetitive antigen exposure during chronic infection, parasite-specific CD8+ T cells from multiple organs expressed high levels of KLRG1, but exhibit a preferential accumulation of CD69+ cells in skeletal muscle, indicating recent antigen encounter in a niche for T. cruzi persistence. A significant proportion of CD8+ T cells in the muscle also produced IFNγ, TNFα and granzyme B in situ, an indication of their detection of and functional response to T. cruzi in vivo. CD8+ T cell function was crucial for the control of parasite burden during chronic infection as exacerbation of parasite load was observed upon depletion of this population. Attempts to improve T cell function by blocking PD-1 or IL-10, potential negative regulators of T cells, failed to increase IFNγ and TNFα production or to enhance T. cruzi clearance. These results highlight the capacity of the CD8+ T cell population to retain essential in vivo function despite chronic antigen stimulation and support a model in which CD8+ T cell dysfunction plays a negligible role in the ability of Trypanosoma cruzi to persist in mice. The parasite Trypanosoma cruzi establishes lifelong infections in humans and other mammals, leading to severe cardiac and gastrointestinal complications known as Chagas disease. Although the factors that enable T. cruzi persistence remain undefined, in this and many other infection models, pathogen persistence has been attributed to the exhaustion of the immune system, particularly of CD8+ T cells. Here, we show that the inability of hosts to fully resolve T. cruzi infection is not a result of immune exhaustion and that in fact the T. cruzi-specific CD8+ T cell population remains highly competent and actively suppresses parasite outgrowth throughout the chronic infection. These results demonstrate that compromised immunity is not the eventual outcome of all chronic infections and suggest that T. cruzi, and perhaps other pathogens, may employ alternative strategies to subvert immune clearance in the presence of highly functional pathogen-specific effectors. These findings also suggest that interventions to inhibit immune regulatory pathways or to otherwise boost existing immune responses in such infections, will have limited benefit.
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Affiliation(s)
- Angela D. Pack
- Department of Microbiology, University of Georgia, Athens, Georgia, United States of America
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, United States of America
| | - Matthew H. Collins
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, United States of America
- Department of Cellular Biology, University of Georgia, Athens, Georgia, United States of America
| | - Charles S. Rosenberg
- Department of Microbiology, University of Georgia, Athens, Georgia, United States of America
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, United States of America
| | - Rick L. Tarleton
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, United States of America
- Department of Cellular Biology, University of Georgia, Athens, Georgia, United States of America
- * E-mail:
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19
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Acevedo GR, Girard MC, Gómez KA. The Unsolved Jigsaw Puzzle of the Immune Response in Chagas Disease. Front Immunol 2018; 9:1929. [PMID: 30197647 PMCID: PMC6117404 DOI: 10.3389/fimmu.2018.01929] [Citation(s) in RCA: 77] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Accepted: 08/06/2018] [Indexed: 12/26/2022] Open
Abstract
Trypanosoma cruzi interacts with the different arms of the innate and adaptive host's immune response in a very complex and flowery manner. The history of host-parasite co-evolution has provided this protozoan with means of resisting, escaping or subverting the mechanisms of immunity and establishing a chronic infection. Despite many decades of research on the subject, the infection remains incurable, and the factors that steer chronic Chagas disease from an asymptomatic state to clinical onset are still unclear. As the relationship between T. cruzi and the host immune system is intricate, so is the amount and diversity of scientific knowledge on the matter. Many of the mechanisms of immunity are fairly well understood, but unveiling the factors that lead each of these to success or failure, within the coordinated response as a whole, requires further research. The intention behind this Review is to compile the available information on the different aspects of the immune response, with an emphasis on those phenomena that have been studied and confirmed in the human host. For ease of comprehension, it has been subdivided in sections that cover the main humoral and cell-mediated components involved therein. However, we also intend to underline that these elements are not independent, but function intimately and concertedly. Here, we summarize years of investigation carried out to unravel the puzzling interplay between the host and the parasite.
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Affiliation(s)
| | | | - Karina A. Gómez
- Laboratorio de Inmunología de las Infecciones por Tripanosomátidos, Instituto de Investigaciones en Ingeniería Genética y Biología Molecular (INGEBI), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
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20
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McCall LI, Tripathi A, Vargas F, Knight R, Dorrestein PC, Siqueira-Neto JL. Experimental Chagas disease-induced perturbations of the fecal microbiome and metabolome. PLoS Negl Trop Dis 2018. [PMID: 29529084 PMCID: PMC5864088 DOI: 10.1371/journal.pntd.0006344] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Trypanosoma cruzi parasites are the causative agents of Chagas disease. These parasites infect cardiac and gastrointestinal tissues, leading to local inflammation and tissue damage. Digestive Chagas disease is associated with perturbations in food absorption, intestinal traffic and defecation. However, the impact of T. cruzi infection on the gut microbiota and metabolome have yet to be characterized. In this study, we applied mass spectrometry-based metabolomics and 16S rRNA sequencing to profile infection-associated alterations in fecal bacterial composition and fecal metabolome through the acute-stage and into the chronic stage of infection, in a murine model of Chagas disease. We observed joint microbial and chemical perturbations associated with T. cruzi infection. These included alterations in conjugated linoleic acid (CLA) derivatives and in specific members of families Ruminococcaceae and Lachnospiraceae, as well as alterations in secondary bile acids and members of order Clostridiales. These results highlight the importance of multi-‘omics’ and poly-microbial studies in understanding parasitic diseases in general, and Chagas disease in particular. Host-parasite interactions are usually studied as a binary system, without considering the role of the host microbiota. This work integrates microbiome research into the study of gastrointestinal Chagas disease. We show that T. cruzi infection perturbs the fecal microbiome and metabolome, indicating functional changes affecting the gastrointestinal lumen. Our results support further investigation into the role of the microbiota-parasite interaction in gastrointestinal Chagas disease pathogenesis.
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Affiliation(s)
- Laura-Isobel McCall
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, California, United States of America
| | - Anupriya Tripathi
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, California, United States of America.,Division of Biological Sciences, University of California San Diego, La Jolla, California, United States of America.,Department of Pediatrics, University of California San Diego, La Jolla, California, United States of America
| | - Fernando Vargas
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, California, United States of America.,Center for Microbiome Innovation, University of California San Diego, La Jolla, California, United States of America.,Collaborative Mass Spectrometry Innovation Center, University of California San Diego, La Jolla, California, United States of America
| | - Rob Knight
- Department of Pediatrics, University of California San Diego, La Jolla, California, United States of America.,Center for Microbiome Innovation, University of California San Diego, La Jolla, California, United States of America.,Department of Computer Science and Engineering, University of California San Diego, La Jolla, California, United States of America
| | - Pieter C Dorrestein
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, California, United States of America.,Center for Microbiome Innovation, University of California San Diego, La Jolla, California, United States of America.,Collaborative Mass Spectrometry Innovation Center, University of California San Diego, La Jolla, California, United States of America
| | - Jair L Siqueira-Neto
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, California, United States of America
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21
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Bivona AE, Sánchez Alberti A, Matos MN, Cerny N, Cardoso AC, Morales C, González G, Cazorla SI, Malchiodi EL. Trypanosoma cruzi 80 kDa prolyl oligopeptidase (Tc80) as a novel immunogen for Chagas disease vaccine. PLoS Negl Trop Dis 2018; 12:e0006384. [PMID: 29601585 PMCID: PMC5895069 DOI: 10.1371/journal.pntd.0006384] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Revised: 04/11/2018] [Accepted: 03/12/2018] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND Chagas disease, also known as American Trypanosomiasis, is a chronic parasitic disease caused by the flagellated protozoan Trypanosoma cruzi that affects about 8 million people around the world where more than 25 million are at risk of contracting the infection. Despite of being endemic on 21 Latin-American countries, Chagas disease has become a global concern due to migratory movements. Unfortunately, available drugs for the treatment have several limitations and they are generally administered during the chronic phase of the infection, when its efficacy is considered controversial. Thus, prophylactic and/or therapeutic vaccines are emerging as interesting control alternatives. In this work, we proposed Trypanosoma cruzi 80 kDa prolyl oligopeptidase (Tc80) as a new antigen for vaccine development against Chagas disease. METHODOLOGY/PRINCIPAL FINDINGS In a murine model, we analyzed the immune response triggered by different immunization protocols based on Tc80 and evaluated their ability to confer protection against a challenge with the parasite. Immunized mice developed Tc80-specific antibodies which were able to carry out different functions such as: enzymatic inhibition, neutralization of parasite infection and complement-mediated lysis of trypomastigotes. Furthermore, vaccinated mice elicited strong cell-mediated immunity. Spleen cells from immunized mice proliferated and secreted Th1 cytokines (IL-2, IFN-γ and TNF-α) upon re-stimulation with rTc80. Moreover, we found Tc80-specific polyfunctional CD4 T cells, and cytotoxic T lymphocyte activity against one Tc80 MHC-I peptide. Immunization protocols conferred protection against a T. cruzi lethal challenge. Immunized groups showed a decreased parasitemia and higher survival rate compared with non-immunized control mice. Moreover, during the chronic phase of the infection, immunized mice presented: lower levels of myopathy-linked enzymes, parasite burden, electrocardiographic disorders and inflammatory cells. CONCLUSIONS/SIGNIFICANCE Considering that an early control of parasite burden and tissue damage might contribute to avoid the progression towards symptomatic forms of chronic Chagas disease, the efficacy of Tc80-based vaccines make this molecule a promising immunogen for a mono or multicomponent vaccine against T. cruzi infection.
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Affiliation(s)
- Augusto E. Bivona
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Inmunología and Instituto de Estudios de la Inmunidad Humoral Ricardo A. Margni (IDEHU), UBA-CONICET, Buenos Aires, Argentina
- Universidad de Buenos Aires, Facultad de Medicina, Departamento de Microbiología, Parasitología e Inmunología and Instituto de Microbiología y Parasitología Médica (IMPaM), UBA-CONICET, Buenos Aires, Argentina
| | - Andrés Sánchez Alberti
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Inmunología and Instituto de Estudios de la Inmunidad Humoral Ricardo A. Margni (IDEHU), UBA-CONICET, Buenos Aires, Argentina
- Universidad de Buenos Aires, Facultad de Medicina, Departamento de Microbiología, Parasitología e Inmunología and Instituto de Microbiología y Parasitología Médica (IMPaM), UBA-CONICET, Buenos Aires, Argentina
| | - Marina N. Matos
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Inmunología and Instituto de Estudios de la Inmunidad Humoral Ricardo A. Margni (IDEHU), UBA-CONICET, Buenos Aires, Argentina
- Universidad de Buenos Aires, Facultad de Medicina, Departamento de Microbiología, Parasitología e Inmunología and Instituto de Microbiología y Parasitología Médica (IMPaM), UBA-CONICET, Buenos Aires, Argentina
| | - Natacha Cerny
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Inmunología and Instituto de Estudios de la Inmunidad Humoral Ricardo A. Margni (IDEHU), UBA-CONICET, Buenos Aires, Argentina
- Universidad de Buenos Aires, Facultad de Medicina, Departamento de Microbiología, Parasitología e Inmunología and Instituto de Microbiología y Parasitología Médica (IMPaM), UBA-CONICET, Buenos Aires, Argentina
| | - Alejandro C. Cardoso
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Inmunología and Instituto de Estudios de la Inmunidad Humoral Ricardo A. Margni (IDEHU), UBA-CONICET, Buenos Aires, Argentina
- Universidad de Buenos Aires, Facultad de Medicina, Departamento de Microbiología, Parasitología e Inmunología and Instituto de Microbiología y Parasitología Médica (IMPaM), UBA-CONICET, Buenos Aires, Argentina
| | - Celina Morales
- Universidad de Buenos Aires, Facultad de Medicina, Departamento de Patología, Instituto de Fisiopatología Cardiovascular, Buenos Aires, Argentina
| | - Germán González
- Universidad de Buenos Aires, Facultad de Medicina, Departamento de Patología, Instituto de Fisiopatología Cardiovascular, Buenos Aires, Argentina
| | - Silvia I. Cazorla
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Inmunología and Instituto de Estudios de la Inmunidad Humoral Ricardo A. Margni (IDEHU), UBA-CONICET, Buenos Aires, Argentina
- Universidad de Buenos Aires, Facultad de Medicina, Departamento de Microbiología, Parasitología e Inmunología and Instituto de Microbiología y Parasitología Médica (IMPaM), UBA-CONICET, Buenos Aires, Argentina
- Laboratorio de Inmunología, Centro de Referencia para Lactobacilos (CERELA-CONICET). Tucumán, Argentina
| | - Emilio L. Malchiodi
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Inmunología and Instituto de Estudios de la Inmunidad Humoral Ricardo A. Margni (IDEHU), UBA-CONICET, Buenos Aires, Argentina
- Universidad de Buenos Aires, Facultad de Medicina, Departamento de Microbiología, Parasitología e Inmunología and Instituto de Microbiología y Parasitología Médica (IMPaM), UBA-CONICET, Buenos Aires, Argentina
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Arroyo-Olarte RD, Martínez I, Cruz-Rivera M, Mendlovic F, Espinoza B. Complement system contributes to modulate the infectivity of susceptible TcI strains of Trypanosoma cruzi. Mem Inst Oswaldo Cruz 2018. [PMID: 29513875 PMCID: PMC5851054 DOI: 10.1590/0074-02760170332] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
BACKGROUND Trypanosoma cruzi is a protozoan parasite and an etiological agent of Chagas disease. There is a wide variability in the clinical outcome of its infection, ranging from asymptomatic individuals to those with chronic fatal mega syndromes. Both parasite and host factors, as well as their interplay, are thought to be involved in the process. OBJECTIVES To evaluate the resistance to complement-mediated killing in two T. cruzi TcI strains with differential virulence and the subsequent effect on their infectivity in mammalian cells. METHODS Tissue-culture derived trypomastigotes of both strains were incubated in guinea pig serum and subjected to flow cytometry in order to determine their viability and complement activations. Trypomastigotes were also incubated on host cells monolayers in the presence of serum, and infectivity was evaluated under different conditions of complement pathway inhibition. Relative expression of the main parasite-specific complement receptors between the two strains was assessed by quantitative real-time polymerase chain reaction. FINDINGS In this work, we showed that two TcI strains, one with lower virulence (Ninoa) compared to the other (Qro), differ in their resistance to the lytic activity of complement system, hence causing a compromised ability of Ninoa strain to invade mammalian cells. These results correlate with the three-fold lower messenger RNA (mRNA) levels of complement regulatory protein (CRP), trypomastigote-decay acceleration factor (T-DAF), and complement C2 receptor inhibitor trispanning (CRIT) in Ninoa compared to those in Qro. On the other hand, calreticulin (CRT) mRNA and surface protein levels were higher in Ninoa strain and promoted its infectivity when the lectin pathway of the complement system was inhibited. MAIN CONCLUSIONS This work suggests the complex interplay of CRP, T-DAF, CRIT, and CRT, and the diagnostic value of mRNA levels in the assessment of virulence potential of T. cruzi strains, particularly when dealing with isolates with similar genetic background.
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Affiliation(s)
- Ruben D Arroyo-Olarte
- Universidad Nacional Autónoma de México, Instituto de Investigaciones Biomedicas, Departamento de Immunología, Ciudad de Mexico, Mexico
| | - Ignacio Martínez
- Universidad Nacional Autónoma de México, Instituto de Investigaciones Biomedicas, Departamento de Immunología, Ciudad de Mexico, Mexico
| | - Mayra Cruz-Rivera
- Universidad Nacional Autónoma de México, Facultad de Medicina, Departamento de Microbiología y Parasitología, Ciudad de Mexico, Mexico
| | - Fela Mendlovic
- Universidad Nacional Autónoma de México, Facultad de Medicina, Departamento de Microbiología y Parasitología, Ciudad de Mexico, Mexico.,Universidad Anahuac, Facultad de Ciencias de la Salud, Mexico Norte, Estado de Mexico, Mexico
| | - Bertha Espinoza
- Universidad Nacional Autónoma de México, Instituto de Investigaciones Biomedicas, Departamento de Immunología, Ciudad de Mexico, Mexico
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Poncini CV, González-Cappa SM. Dual role of monocyte-derived dendritic cells in Trypanosoma cruzi infection. Eur J Immunol 2017; 47:1936-1948. [PMID: 28748529 DOI: 10.1002/eji.201646830] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Revised: 05/22/2017] [Accepted: 07/05/2017] [Indexed: 01/29/2023]
Abstract
Pathogens can cause inflammation when inoculated into the skin. The vector-transmitted protozoan parasite Trypanosoma cruzi induces poor cellular-infiltration and disseminates, causing high mortality in the experimental model. Here, we characterized the inflammatory foci at the parasite inoculation site and secondary lymphoid organs using a murine model. While no macrophages and few neutrophils and monocytes (Mo) were recruited into the skin, T. cruzi infection elicited the mobilization of Ly6C+ Mo to draining lymph nodes and spleen. Over time, this population became enriched in CD11b+ Ly6C+ CD11c+ MHCII+ CD86+ cells resembling inflammatory dendritic cells (DCs). Adoptive transfer of Ly6C+ Mo purified from the bone marrow of CD11c-GFP transgenic mice confirmed the monocytic origin of Ly6C+ DCs found in the spleen of infected animals. Isolated Mo-derived cells not only produced TNF-α and nitric oxide, but also IL-10 and displayed a poor capacity to induce lymphoproliferation. Ablation of Mo-derived cells by 5-fluorouracil confirmed their dual role during infection, limiting the parasite load by inducible nitric oxide synthase-related mechanisms and negatively affecting the development of anti-parasite T-cell response. This study demonstrated that consistent with their antagonistic properties, these cells not only control the parasite spreading but also its persistence in the host.
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Affiliation(s)
- Carolina V Poncini
- Instituto de Investigaciones en Microbiología y Parasitología Médicas (IMPaM), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)-Universidad de Buenos Aires, Argentina.,Departamento de Microbiología, Facultad de Medicina, Universidad de Buenos Aires, CABA, Argentina
| | - Stella M González-Cappa
- Instituto de Investigaciones en Microbiología y Parasitología Médicas (IMPaM), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)-Universidad de Buenos Aires, Argentina.,Departamento de Microbiología, Facultad de Medicina, Universidad de Buenos Aires, CABA, Argentina
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Balouz V, Agüero F, Buscaglia CA. Chagas Disease Diagnostic Applications: Present Knowledge and Future Steps. ADVANCES IN PARASITOLOGY 2016; 97:1-45. [PMID: 28325368 PMCID: PMC5363286 DOI: 10.1016/bs.apar.2016.10.001] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Chagas disease, caused by the protozoan Trypanosoma cruzi, is a lifelong and debilitating illness of major significance throughout Latin America and an emergent threat to global public health. Being a neglected disease, the vast majority of Chagasic patients have limited access to proper diagnosis and treatment, and there is only a marginal investment into R&D for drug and vaccine development. In this context, identification of novel biomarkers able to transcend the current limits of diagnostic methods surfaces as a main priority in Chagas disease applied research. The expectation is that these novel biomarkers will provide reliable, reproducible and accurate results irrespective of the genetic background, infecting parasite strain, stage of disease, and clinical-associated features of Chagasic populations. In addition, they should be able to address other still unmet diagnostic needs, including early detection of congenital T. cruzi transmission, rapid assessment of treatment efficiency or failure, indication/prediction of disease progression and direct parasite typification in clinical samples. The lack of access of poor and neglected populations to essential diagnostics also stresses the necessity of developing new methods operational in point-of-care settings. In summary, emergent diagnostic tests integrating these novel and tailored tools should provide a significant impact on the effectiveness of current intervention schemes and on the clinical management of Chagasic patients. In this chapter, we discuss the present knowledge and possible future steps in Chagas disease diagnostic applications, as well as the opportunity provided by recent advances in high-throughput methods for biomarker discovery.
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Affiliation(s)
- Virginia Balouz
- Instituto de Investigaciones Biotecnológicas - Instituto Tecnológico de Chascomús (IIB-INTECH), Universidad Nacional de San Martín (UNSAM) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), San Martín, B 1650 HMP, Buenos Aires, Argentina
| | - Fernán Agüero
- Instituto de Investigaciones Biotecnológicas - Instituto Tecnológico de Chascomús (IIB-INTECH), Universidad Nacional de San Martín (UNSAM) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), San Martín, B 1650 HMP, Buenos Aires, Argentina
| | - Carlos A. Buscaglia
- Instituto de Investigaciones Biotecnológicas - Instituto Tecnológico de Chascomús (IIB-INTECH), Universidad Nacional de San Martín (UNSAM) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), San Martín, B 1650 HMP, Buenos Aires, Argentina
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Long-Term Immunity to Trypanosoma cruzi in the Absence of Immunodominant trans-Sialidase-Specific CD8+ T Cells. Infect Immun 2016; 84:2627-38. [PMID: 27354447 DOI: 10.1128/iai.00241-16] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Accepted: 06/24/2016] [Indexed: 11/20/2022] Open
Abstract
Trypanosoma cruzi infection drives the expansion of remarkably focused CD8(+) T cell responses targeting epitopes encoded by variant trans-sialidase (TS) genes. Infection of C57BL/6 mice with T. cruzi results in up to 40% of all CD8(+) T cells committed to recognition of the dominant TSKB20 and subdominant TSKB18 TS epitopes. However, despite this enormous response, these mice fail to clear T. cruzi infection and subsequently develop chronic disease. One possible reason for the failure to cure T. cruzi infection is that immunodomination by these TS-specific T cells may interfere with alternative CD8(+) T cell responses more capable of complete parasite elimination. To address this possibility, we created transgenic mice that are centrally tolerant to these immunodominant epitopes. Mice expressing TSKB20, TSKB18, or both epitopes controlled T. cruzi infection and developed effector CD8(+) T cells that maintained an activated phenotype. Memory CD8(+) T cells from drug-cured TSKB-transgenic mice rapidly responded to secondary T. cruzi infection. In the absence of the response to TSKB20 and TSKB18, immunodominance did not shift to other known subdominant epitopes despite the capacity of these mice to expand epitope-specific T cells specific for the model antigen ovalbumin expressed by engineered parasites. Thus, CD8(+) T cell responses tightly and robustly focused on a few epitopes within variant TS antigens appear to neither contribute to, nor detract from, the ability to control T. cruzi infection. These data also indicate that the relative position of an epitope within a CD8(+) immunodominance hierarchy does not predict its importance in pathogen control.
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26
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Morrot A, Villar SR, González FB, Pérez AR. Evasion and Immuno-Endocrine Regulation in Parasite Infection: Two Sides of the Same Coin in Chagas Disease? Front Microbiol 2016; 7:704. [PMID: 27242726 PMCID: PMC4876113 DOI: 10.3389/fmicb.2016.00704] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Accepted: 04/28/2016] [Indexed: 12/16/2022] Open
Abstract
Chagas disease is a serious illness caused by the protozoan parasite Trypanosoma cruzi. Nearly 30% of chronically infected people develop cardiac, digestive, or mixed alterations, suggesting a broad range of host-parasite interactions that finally impact upon chronic disease outcome. The ability of T. cruzi to persist and cause pathology seems to depend on diverse factors like T. cruzi strains, the infective load and the route of infection, presence of virulence factors, the parasite capacity to avoid protective immune response, the strength and type of host defense mechanisms and the genetic background of the host. The host-parasite interaction is subject to a constant neuro-endocrine regulation that is thought to influence the adaptive immune system, and as the infection proceeds it can lead to a broad range of outcomes, ranging from pathogen elimination to its continued persistence in the host. In this context, T. cruzi evasion strategies and host defense mechanisms can be envisioned as two sides of the same coin, influencing parasite persistence and different outcomes observed in Chagas disease. Understanding how T. cruzi evade host's innate and adaptive immune response will provide important clues to better dissect mechanisms underlying the pathophysiology of Chagas disease.
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Affiliation(s)
- Alexandre Morrot
- Institute of Microbiology, Federal University of Rio de Janeiro Rio de Janeiro, Brazil
| | - Silvina R Villar
- Institute of Clinical and Experimental Immunology of Rosario, CONICET, National University of RosarioRosario, Argentina; Faculty of Medical Sciences, National University of RosarioRosario, Argentina
| | - Florencia B González
- Institute of Clinical and Experimental Immunology of Rosario, CONICET, National University of RosarioRosario, Argentina; Faculty of Medical Sciences, National University of RosarioRosario, Argentina
| | - Ana R Pérez
- Institute of Clinical and Experimental Immunology of Rosario, CONICET, National University of RosarioRosario, Argentina; Faculty of Medical Sciences, National University of RosarioRosario, Argentina
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Cardoso MS, Reis-Cunha JL, Bartholomeu DC. Evasion of the Immune Response by Trypanosoma cruzi during Acute Infection. Front Immunol 2016; 6:659. [PMID: 26834737 PMCID: PMC4716143 DOI: 10.3389/fimmu.2015.00659] [Citation(s) in RCA: 87] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Accepted: 12/24/2015] [Indexed: 12/11/2022] Open
Abstract
Trypanosoma cruzi is the etiologic agent of Chagas disease, a neglected tropical disease that affects millions of people mainly in Latin America. To establish a life-long infection, T. cruzi must subvert the vertebrate host's immune system, using strategies that can be traced to the parasite's life cycle. Once inside the vertebrate host, metacyclic trypomastigotes rapidly invade a wide variety of nucleated host cells in a membrane-bound compartment known as the parasitophorous vacuole, which fuses to lysosomes, originating the phagolysosome. In this compartment, the parasite relies on a complex network of antioxidant enzymes to shield itself from lysosomal oxygen and nitrogen reactive species. Lysosomal acidification of the parasitophorous vacuole is an important factor that allows trypomastigote escape from the extremely oxidative environment of the phagolysosome to the cytoplasm, where it differentiates into amastigote forms. In the cytosol of infected macrophages, oxidative stress instead of being detrimental to the parasite, favors amastigote burden, which then differentiates into bloodstream trypomastigotes. Trypomastigotes released in the bloodstream upon the rupture of the host cell membrane express surface molecules, such as calreticulin and GP160 proteins, which disrupt initial and key components of the complement pathway, while others such as glycosylphosphatidylinositol-mucins stimulate immunoregulatory receptors, delaying the progression of a protective immune response. After an immunologically silent entry at the early phase of infection, T. cruzi elicits polyclonal B cell activation, hypergammaglobulinemia, and unspecific anti-T. cruzi antibodies, which are inefficient in controlling the infection. Additionally, the coexpression of several related, but not identical, epitopes derived from trypomastigote surface proteins delays the generation of T. cruzi-specific neutralizing antibodies. Later in the infection, the establishment of an anti-T. cruzi CD8(+) immune response focused on the parasite's immunodominant epitopes controls parasitemia and tissue infection, but fails to completely eliminate the parasite. This outcome is not detrimental to the parasite, as it reduces host mortality and maintains the parasite infectivity toward the insect vectors.
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Affiliation(s)
- Mariana S Cardoso
- Laboratório de Imunologia e Genômica de Parasitos, Departamento de Parasitologia, Universidade Federal de Minas Gerais , Belo Horizonte , Minas Gerais, Brazil
| | - João Luís Reis-Cunha
- Laboratório de Imunologia e Genômica de Parasitos, Departamento de Parasitologia, Universidade Federal de Minas Gerais , Belo Horizonte , Minas Gerais, Brazil
| | - Daniella C Bartholomeu
- Laboratório de Imunologia e Genômica de Parasitos, Departamento de Parasitologia, Universidade Federal de Minas Gerais , Belo Horizonte , Minas Gerais, Brazil
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Concomitant Benznidazole and Suramin Chemotherapy in Mice Infected with a Virulent Strain of Trypanosoma cruzi. Antimicrob Agents Chemother 2015; 59:5999-6006. [PMID: 26169419 DOI: 10.1128/aac.00779-15] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Accepted: 07/09/2015] [Indexed: 12/22/2022] Open
Abstract
Although suramin (Sur) is suggested as a potential drug candidate in the management of Chagas disease, this issue has not been objectively tested. In this study, we examined the applicability of concomitant treatment with benznidazole (Bz) and suramin in mice infected with a virulent strain of Trypanosoma cruzi. Eighty 12-week-old male C57BL/6 mice were equally randomized in eight groups: (i) noninfected mice (negative control) and mice infected with T. cruzi Y strain receiving (ii) no treatment (positive control), (iii) Bz, 100 mg/kg of body weight per day, (iv) Sur, 20 mg/kg/day, and (v to viii) Sur, 20 mg/kg/day, combined with Bz, 100, 50, 25, or 5 mg/kg/day. Bz was administered by gavage, and Sur was administered intraperitoneally. Sur dramatically increased the parasitemia, cardiac content of parasite DNA, inflammation, oxidative tissue damage, and mortality. In response to high parasitic load in cardiac tissue, Sur stimulated the immune system in a manner typical of the acute phase of Chagas disease, increasing tissue levels of gamma interferon (IFN-γ) and tumor necrosis factor alpha (TNF-α) and inducing a preferential IgG2a anti-T. cruzi serum pattern. When Sur and Bz were combined, the infection severity was attenuated, showing a dose-dependent Bz response. Sur therapy had a more harmful effect on the host than on the parasite and reduced the efficacy of Bz against T. cruzi infection. Considering that Sur drastically reinforced the infection evolution, potentiating the inflammatory process and the severity of cardiac lesions, the in vivo findings contradicted the in vitro anti-T. cruzi potential described for this drug.
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Immune Evasion Strategies of Trypanosoma cruzi. J Immunol Res 2015; 2015:178947. [PMID: 26240832 PMCID: PMC4512591 DOI: 10.1155/2015/178947] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Accepted: 12/31/2014] [Indexed: 01/03/2023] Open
Abstract
Microbes have evolved a diverse range of strategies to subvert the host immune system. The protozoan parasite Trypanosoma cruzi, the causative agent of Chagas disease, provides a good example of such adaptations. This parasite targets a broad spectrum of host tissues including both peripheral and central lymphoid tissues. Rapid colonization of the host gives rise to a systemic acute response which the parasite must overcome. The parasite in fact undermines both innate and adaptive immunity. It interferes with the antigen presenting function of dendritic cells via an action on host sialic acid-binding Ig-like lectin receptors. These receptors also induce suppression of CD4(+) T cells responses, and we presented evidence that the sialylation of parasite-derived mucins is required for the inhibitory effects on CD4 T cells. In this review we highlight the major mechanisms used by Trypanosoma cruzi to overcome host immunity and discuss the role of parasite colonization of the central thymic lymphoid tissue in chronic disease.
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30
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Li HW, Andreola G, Carlson AL, Shao S, Lin CP, Zhao G, Sykes M. Rapid Functional Decline of Activated and Memory Graft-versus-Host-Reactive T Cells Encountering Host Antigens in the Absence of Inflammation. THE JOURNAL OF IMMUNOLOGY 2015; 195:1282-92. [PMID: 26085679 DOI: 10.4049/jimmunol.1401511] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Accepted: 05/22/2015] [Indexed: 01/04/2023]
Abstract
Inflammation in the priming host environment has critical effects on the graft-versus-host (GVH) responses mediated by naive donor T cells. However, it is unclear how a quiescent or inflammatory environment impacts the activity of GVH-reactive primed T and memory cells. We show in this article that GVH-reactive primed donor T cells generated in irradiated recipients had diminished ability compared with naive T cells to increase donor chimerism when transferred to quiescent mixed allogeneic chimeras. GVH-reactive primed T cells showed marked loss of cytotoxic function and activation, and delayed but not decreased proliferation or accumulation in lymphoid tissues when transferred to quiescent mixed chimeras compared with freshly irradiated secondary recipients. Primed CD4 and CD8 T cells provided mutual help to sustain these functions in both subsets. CD8 help for CD4 cells was largely IFN-γ dependent. TLR stimulation after transfer of GVH-reactive primed T cells to mixed chimeras restored their cytotoxic effector function and permitted the generation of more effective T cell memory in association with reduced PD-1 expression on CD4 memory cells. Our data indicate that an inflammatory host environment is required for the maintenance of GVH-reactive primed T cell functions and the generation of memory T cells that can rapidly acquire effector functions. These findings have important implications for graft-versus-host disease and T cell-mediated immunotherapies.
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Affiliation(s)
- Hao Wei Li
- Columbia Center for Translational Immunology, Columbia University Medical Center, New York, NY 10032; Transplantation Biology Research Center, Massachusetts General Hospital/Harvard Medical School, Boston, MA 02129
| | - Giovanna Andreola
- Transplantation Biology Research Center, Massachusetts General Hospital/Harvard Medical School, Boston, MA 02129
| | - Alicia L Carlson
- Advanced Microscopy Program, Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, MA 02114; and Center for Systems Biology, Massachusetts General Hospital, Boston, MA 02114
| | - Steven Shao
- Columbia Center for Translational Immunology, Columbia University Medical Center, New York, NY 10032
| | - Charles P Lin
- Advanced Microscopy Program, Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, MA 02114; and Center for Systems Biology, Massachusetts General Hospital, Boston, MA 02114
| | - Guiling Zhao
- Columbia Center for Translational Immunology, Columbia University Medical Center, New York, NY 10032; Transplantation Biology Research Center, Massachusetts General Hospital/Harvard Medical School, Boston, MA 02129
| | - Megan Sykes
- Columbia Center for Translational Immunology, Columbia University Medical Center, New York, NY 10032; Transplantation Biology Research Center, Massachusetts General Hospital/Harvard Medical School, Boston, MA 02129;
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Kurup SP, Tarleton RL. The Trypanosoma cruzi flagellum is discarded via asymmetric cell division following invasion and provides early targets for protective CD8⁺ T cells. Cell Host Microbe 2015; 16:439-49. [PMID: 25299330 DOI: 10.1016/j.chom.2014.09.003] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Revised: 07/11/2014] [Accepted: 08/27/2014] [Indexed: 12/27/2022]
Abstract
During invasion of host cells by Trypanosoma cruzi, the parasite that causes Chagas disease, the elongated, flagellated trypomastigotes remodel into oval amastigotes with no external flagellum. The underlying mechanism of this remodeling and the fate of the flagellum are obscure. We discovered that T. cruzi trypomastigotes discard their flagella via an asymmetric cellular division. The flagellar proteins liberated become among the earliest parasite proteins to enter the MHC-I processing pathway in infected cells. Indeed, paraflagellar rod protein PAR4-specific CD8(+) T cells detect infected host cells >20 hr earlier than immunodominant trans-sialidase-specific T cells. Overexpression of PAR4 in T. cruzi enhanced the subdominant PAR4-specific CD8(+) T cell response, resulting in improved control of a challenge infection. These results provide insights into previously unappreciated events in intracellular invasion by T. cruzi and highlight the importance of T cells that recognize infected host cells early in the infectious process, in the control of infections.
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Affiliation(s)
- Samarchith P Kurup
- Department of Cellular Biology and Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA 30602, USA
| | - Rick L Tarleton
- Department of Cellular Biology and Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA 30602, USA.
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Khan IA. CD8+ T cell immune response against non-viral pathogens. Semin Immunopathol 2015; 37:209-10. [PMID: 25944515 DOI: 10.1007/s00281-015-0489-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2015] [Accepted: 04/06/2015] [Indexed: 10/23/2022]
Affiliation(s)
- Imtiaz A Khan
- Department of Microbiology, Immunology and Tropical Medicine, George Washington University, Washington, DC, 20037, USA,
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Abstract
Trypanosoma cruzi infection and Chagas disease remains among the most neglected of the neglected tropical diseases. Despite this, studies of the immune response to T. cruzi have provided new insights in immunology and guidance for approaches for prevention and treatment of the disease. T. cruzi represents one of the very best systems in which to study CD8(+) T cell biology; mice, dogs, and primates (and many other mammals) are all natural hosts for this parasite, the robust T cell responses generated in these hosts can be readily monitored using the full range of cutting edge techniques, and the parasite can be easily modified to express (or not) a variety of tags, reporters, immune enhances, and endogenous or model antigens. The infection in most hosts is characterized by vigorous and largely effective immune responses, including CD8(+) T cells capable of controlling T. cruzi at the level of the infected host cells. However, this immune control is only partially effective and most hosts maintain a low level infection for life. This review addresses the interplay of highly effective CD8(+) T cell responses with elaborate pathogen immune evasion mechanisms, including the generation and simultaneous expression of highly variant CD8(+) T cell targets and a host cell invasion mechanisms that largely eludes innate immune detection.
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Affiliation(s)
- Rick L Tarleton
- Center for Tropical and Emerging Global Diseases and Department of Cellular Biology, University of Georgia, Athens, GA, 30602, USA,
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Bustamante J, Tarleton R. Reaching for the Holy Grail: insights from infection/cure models on the prospects for vaccines for Trypanosoma cruzi infection. Mem Inst Oswaldo Cruz 2015; 110:445-51. [PMID: 25946159 PMCID: PMC4489482 DOI: 10.1590/0074-02760140440] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Accepted: 02/25/2015] [Indexed: 11/21/2022] Open
Abstract
Prevention of Trypanosoma cruzi infection in mammals likely depends
on either prevention of the invading trypomastigotes from infecting host cells or the
rapid recognition and killing of the newly infected cells by T.
cruzi-specific T cells. We show here that multiple rounds of infection
and cure (by drug therapy) fails to protect mice from reinfection, despite the
generation of potent T cell responses. This disappointing result is similar to that
obtained with many other vaccine protocols used in attempts to protect animals
from T. cruzi infection. We have previously shown that immune
recognition of T. cruzi infection is significantly delayed both at
the systemic level and at the level of the infected host cell. The systemic delay
appears to be the result of a stealth infection process that fails to trigger
substantial innate recognition mechanisms while the delay at the cellular level is
related to the immunodominance of highly variable gene family proteins, in particular
those of the trans-sialidase family. Here we discuss how these previous studies and
the new findings herein impact our thoughts on the potential of prophylactic
vaccination to serve a productive role in the prevention of T. cruzi
infection and Chagas disease.
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Affiliation(s)
- Juan Bustamante
- Centro de Investigación en Salud Internacional de Barcelona, Hospital Clínic, Universitat de Barcelona, Barcelona, Spain
| | - Rick Tarleton
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, USA
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CD8(+) T cell-mediated immunity during Trypanosoma cruzi infection: a path for vaccine development? Mediators Inflamm 2014; 2014:243786. [PMID: 25104879 PMCID: PMC4102079 DOI: 10.1155/2014/243786] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Accepted: 06/15/2014] [Indexed: 11/05/2022] Open
Abstract
MHC-restricted CD8+ T cells are important during infection with the intracellular protozoan parasite Trypanosoma cruzi, the causative agent of Chagas disease. Experimental studies performed in the past 25 years have elucidated a number of features related to the immune response mediated by these T cells, which are important for establishing the parasite/host equilibrium leading to chronic infection. CD8+ T cells are specific for highly immunodominant antigens expressed by members of the trans-sialidase family. After infection, their activation is delayed, and the cells display a high proliferative activity associated with high apoptotic rates. Although they participate in parasite control and elimination, they are unable to clear the infection due to their low fitness, allowing the parasite to establish the chronic phase when these cells then play an active role in the induction of heart immunopathology. Vaccination with a number of subunit recombinant vaccines aimed at eliciting specific CD8+ T cells can reverse this path, thereby generating a productive immune response that will lead to the control of infection, reduction of symptoms, and reduction of disease transmission. Due to these attributes, activation of CD8+ T lymphocytes may constitute a path for the development of a veterinarian or human vaccine.
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36
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Kurup SP, Tarleton RL. Perpetual expression of PAMPs necessary for optimal immune control and clearance of a persistent pathogen. Nat Commun 2014; 4:2616. [PMID: 24149620 PMCID: PMC4161029 DOI: 10.1038/ncomms3616] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Accepted: 09/16/2013] [Indexed: 11/09/2022] Open
Abstract
Pathogen-associated molecular patterns (PAMPs) are known to be fundamental in instigating immune responses, but their role in influencing these responses beyond their initiation is less well understood. Here, using the protozoan parasite Trypanosoma cruzi, which is deficient in strong PAMPs, we demonstrate a requirement for the continuous expression of PAMPs for optimal anti-pathogen immunity. Although co-inoculating with, temporary anchoring of and transgenic expression of exogenous PAMPs all result in enhanced early adaptive immune responses, only the continuous expression of bacterial PAMPs on transgenic T. cruzi sustains these responses, resulting in enhanced pathogen clearance. These findings demonstrate that PAMPs function to potentiate adaptive immune responses well beyond their initiation and may determine the efficiency of control of pathogens capable of long-term persistence.
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Affiliation(s)
- Samarchith P Kurup
- Department of Cellular Biology and Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia 30602, USA
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37
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Martin DL, Marks M, Galdos-Cardenas G, Gilman RH, Goodhew B, Ferrufino L, Halperin A, Sanchez G, Verastegui M, Escalante P, Naquira C, Levy MZ, Bern C. Regional variation in the correlation of antibody and T-cell responses to Trypanosoma cruzi. Am J Trop Med Hyg 2014; 90:1074-81. [PMID: 24710614 DOI: 10.4269/ajtmh.13-0391] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Chagas disease, caused by the protozoan parasite Trypanosoma cruzi, is a major cause of morbidity and mortality in Central and South America. Geographic variations in the sensitivity of serologic diagnostic assays to T. cruzi may reflect differences in T. cruzi exposure. We measured parasite-specific T-cell responses among seropositive individuals in two populations from South America with widely varying antibody titers against T. cruzi. Antibody titers among seropositive individuals were significantly lower in Arequipa, Peru compared with Santa Cruz, Bolivia. Similarly, the proportion of seropositive individuals with positive T-cell responses was lower in Peru than Bolivia, resulting in overall lower frequencies of interferon-γ (IFNγ)-secreting cells from Peruvian samples. However, the magnitude of the IFNγ response was similar among the IFNγ responders in both locations. These data indicate that immunological discrepancies based on geographic region are reflected in T-cell responses as well as antibody responses.
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Affiliation(s)
- Diana L Martin
- Centers for Disease Control and Prevention, Atlanta, Georgia; National Institutes of Health, Bethesda, Maryland; Johns Hopkins University, Baltimore, Maryland; Hospital Universitario Japones, Santa Cruz, Bolivia; Asociación Benéfica PRISMA, Lima, Peru; Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland; Arequipa Ministry of Health, Arequipa, Peru; University of Pennsylvania, Philadelphia, Pennsylvania; Universidad Peruana Cayetano Heredia, Lima, Perú
| | - Morgan Marks
- Centers for Disease Control and Prevention, Atlanta, Georgia; National Institutes of Health, Bethesda, Maryland; Johns Hopkins University, Baltimore, Maryland; Hospital Universitario Japones, Santa Cruz, Bolivia; Asociación Benéfica PRISMA, Lima, Peru; Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland; Arequipa Ministry of Health, Arequipa, Peru; University of Pennsylvania, Philadelphia, Pennsylvania; Universidad Peruana Cayetano Heredia, Lima, Perú
| | - Gerson Galdos-Cardenas
- Centers for Disease Control and Prevention, Atlanta, Georgia; National Institutes of Health, Bethesda, Maryland; Johns Hopkins University, Baltimore, Maryland; Hospital Universitario Japones, Santa Cruz, Bolivia; Asociación Benéfica PRISMA, Lima, Peru; Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland; Arequipa Ministry of Health, Arequipa, Peru; University of Pennsylvania, Philadelphia, Pennsylvania; Universidad Peruana Cayetano Heredia, Lima, Perú
| | - Robert H Gilman
- Centers for Disease Control and Prevention, Atlanta, Georgia; National Institutes of Health, Bethesda, Maryland; Johns Hopkins University, Baltimore, Maryland; Hospital Universitario Japones, Santa Cruz, Bolivia; Asociación Benéfica PRISMA, Lima, Peru; Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland; Arequipa Ministry of Health, Arequipa, Peru; University of Pennsylvania, Philadelphia, Pennsylvania; Universidad Peruana Cayetano Heredia, Lima, Perú
| | - Brook Goodhew
- Centers for Disease Control and Prevention, Atlanta, Georgia; National Institutes of Health, Bethesda, Maryland; Johns Hopkins University, Baltimore, Maryland; Hospital Universitario Japones, Santa Cruz, Bolivia; Asociación Benéfica PRISMA, Lima, Peru; Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland; Arequipa Ministry of Health, Arequipa, Peru; University of Pennsylvania, Philadelphia, Pennsylvania; Universidad Peruana Cayetano Heredia, Lima, Perú
| | - Lisbeth Ferrufino
- Centers for Disease Control and Prevention, Atlanta, Georgia; National Institutes of Health, Bethesda, Maryland; Johns Hopkins University, Baltimore, Maryland; Hospital Universitario Japones, Santa Cruz, Bolivia; Asociación Benéfica PRISMA, Lima, Peru; Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland; Arequipa Ministry of Health, Arequipa, Peru; University of Pennsylvania, Philadelphia, Pennsylvania; Universidad Peruana Cayetano Heredia, Lima, Perú
| | - Anthony Halperin
- Centers for Disease Control and Prevention, Atlanta, Georgia; National Institutes of Health, Bethesda, Maryland; Johns Hopkins University, Baltimore, Maryland; Hospital Universitario Japones, Santa Cruz, Bolivia; Asociación Benéfica PRISMA, Lima, Peru; Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland; Arequipa Ministry of Health, Arequipa, Peru; University of Pennsylvania, Philadelphia, Pennsylvania; Universidad Peruana Cayetano Heredia, Lima, Perú
| | - Gerardo Sanchez
- Centers for Disease Control and Prevention, Atlanta, Georgia; National Institutes of Health, Bethesda, Maryland; Johns Hopkins University, Baltimore, Maryland; Hospital Universitario Japones, Santa Cruz, Bolivia; Asociación Benéfica PRISMA, Lima, Peru; Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland; Arequipa Ministry of Health, Arequipa, Peru; University of Pennsylvania, Philadelphia, Pennsylvania; Universidad Peruana Cayetano Heredia, Lima, Perú
| | - Manuela Verastegui
- Centers for Disease Control and Prevention, Atlanta, Georgia; National Institutes of Health, Bethesda, Maryland; Johns Hopkins University, Baltimore, Maryland; Hospital Universitario Japones, Santa Cruz, Bolivia; Asociación Benéfica PRISMA, Lima, Peru; Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland; Arequipa Ministry of Health, Arequipa, Peru; University of Pennsylvania, Philadelphia, Pennsylvania; Universidad Peruana Cayetano Heredia, Lima, Perú
| | - Patricia Escalante
- Centers for Disease Control and Prevention, Atlanta, Georgia; National Institutes of Health, Bethesda, Maryland; Johns Hopkins University, Baltimore, Maryland; Hospital Universitario Japones, Santa Cruz, Bolivia; Asociación Benéfica PRISMA, Lima, Peru; Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland; Arequipa Ministry of Health, Arequipa, Peru; University of Pennsylvania, Philadelphia, Pennsylvania; Universidad Peruana Cayetano Heredia, Lima, Perú
| | - Cesar Naquira
- Centers for Disease Control and Prevention, Atlanta, Georgia; National Institutes of Health, Bethesda, Maryland; Johns Hopkins University, Baltimore, Maryland; Hospital Universitario Japones, Santa Cruz, Bolivia; Asociación Benéfica PRISMA, Lima, Peru; Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland; Arequipa Ministry of Health, Arequipa, Peru; University of Pennsylvania, Philadelphia, Pennsylvania; Universidad Peruana Cayetano Heredia, Lima, Perú
| | - Michael Z Levy
- Centers for Disease Control and Prevention, Atlanta, Georgia; National Institutes of Health, Bethesda, Maryland; Johns Hopkins University, Baltimore, Maryland; Hospital Universitario Japones, Santa Cruz, Bolivia; Asociación Benéfica PRISMA, Lima, Peru; Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland; Arequipa Ministry of Health, Arequipa, Peru; University of Pennsylvania, Philadelphia, Pennsylvania; Universidad Peruana Cayetano Heredia, Lima, Perú
| | - Caryn Bern
- Centers for Disease Control and Prevention, Atlanta, Georgia; National Institutes of Health, Bethesda, Maryland; Johns Hopkins University, Baltimore, Maryland; Hospital Universitario Japones, Santa Cruz, Bolivia; Asociación Benéfica PRISMA, Lima, Peru; Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland; Arequipa Ministry of Health, Arequipa, Peru; University of Pennsylvania, Philadelphia, Pennsylvania; Universidad Peruana Cayetano Heredia, Lima, Perú
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38
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Ali OA, Doherty E, Mooney DJ, Emerich D. Relationship of vaccine efficacy to the kinetics of DC and T-cell responses induced by PLG-based cancer vaccines. BIOMATTER 2014; 1:66-75. [PMID: 23507728 PMCID: PMC3548245 DOI: 10.4161/biom.1.1.16277] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Cancer vaccines are typically formulated for bolus injection and often produce short-lived immunostimulation resulting in poor temporal control over immune cell activation and weak oncolytic activity. One means of overcoming these limitations utilizes immunologically active biomaterial constructs. We previously reported that antigen-laden, macroporous PLG scaffolds induce potent dendritic cell (DC) and cytotoxic T-lymphocyte (CTL) responses via the controlled signaling of inflammatory cytokines, antigen and toll-like receptor agonists. In this study, we describe the kinetics of these responses and illustrate their fundamental relationship to potent tumor rejection when implanted subcutaneously in a mouse B16 model of melanoma. By explanting scaffolds from mice at times ranging from 1–7 d, a seamless relationship was observed between the production of controlled CTL responses, tumor growth and long-term survival in both prophylactic and therapeutic models. Scaffolds must be implanted for > 7 d to augment CTL responses via the prolonged presentation of tumor antigen, and the benefits included a notable regression of established tumors. Host DC infiltration into the porous material persisted for 12 days (peaking at day 5 ~1.4 x 106 cells), and a sharp attenuation in DC numbers coincided with peak CD8+ CTL infiltration at day 12 (~8 x 105 cells). Importantly, these PLG systems enhanced DC numbers in the draining lymph node, resulting in increased CD8(+) CTL subsets at days 10–16 of vaccination. These results indicate that material systems can finely control innate and adaptive immune cell responses to kill typically untreatable melanoma tumors and provide critical kinetic data for the design of vaccine carriers.
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Affiliation(s)
- Omar A Ali
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
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Villarino N, Schmidt NW. CD8 + T Cell Responses to Plasmodium and Intracellular Parasites. ACTA ACUST UNITED AC 2014; 9:169-178. [PMID: 24741372 PMCID: PMC3983867 DOI: 10.2174/1573395509666131126232327] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2013] [Revised: 11/14/2013] [Accepted: 11/19/2013] [Indexed: 12/29/2022]
Abstract
Parasitic protozoa are major threats to human health affecting millions of people around the world. Control of these infections by the host immune system relies on a myriad of immunological mechanisms that includes both humoral and cellular immunity. CD8+ T cells contribute to the control of these parasitic infections in both animals and humans. Here, we will focus on the CD8+ T cell response against a subset of these protozoa: Plasmodium, Toxoplasma gondii, Leishmania and Trypanosoma cruzi, with an emphasis on experimental rodent systems. It is evident a complex interaction occurs between CD8+ T cells and the invading protozoa. A detailed understanding of how CD8+ T cells mediate protection should provide the basis for the development of effective vaccines that prevent and control infections by these parasites.
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Affiliation(s)
- Nicolas Villarino
- Department of Microbiology, University of Tennessee, Knoxville, TN 37996, USA
| | - Nathan W Schmidt
- Department of Microbiology, University of Tennessee, Knoxville, TN 37996, USA
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40
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Morrot A. The Role of Sialic Acid-Binding Receptors (Siglecs) in the Immunomodulatory Effects of Trypanosoma cruzi Sialoglycoproteins on the Protective Immunity of the Host. SCIENTIFICA 2013; 2013:965856. [PMID: 24455435 PMCID: PMC3885277 DOI: 10.1155/2013/965856] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/17/2013] [Accepted: 12/10/2013] [Indexed: 06/03/2023]
Abstract
Chagas disease is caused by the protozoan parasite Trypanosoma cruzi and is an important endemic infection in Latin America. Lately, it has also become a health concern in the United States and Europe. Most of the immunomodulatory mechanisms associated with this parasitic infection have been attributed to mucin-like molecules on the T. cruzi surface. Mucins are high molecular weight glycoproteins that are involved in regulating diverse cellular activities in both normal and pathological conditions. In Trypanosoma cruzi infection, the parasite-derived mucins are the main acceptors of sialic acid and it has been suggested that they play a role in various host-parasite interactions during the course of Chagas disease. Recently, we have presented evidence that sialylation of the mucins is required for the inhibitory effects on CD4(+) T cells. In what follows we propose that signaling via sialic acid-binding Ig-like lectin receptors for these highly sialylated structures on host cells contributes to the arrest of cell cycle progression in the G1 phase and may allow the parasite to modulate the immune system of the host.
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Affiliation(s)
- Alexandre Morrot
- Institute of Microbiology, Federal University of Rio de Janeiro, CCS, Sala D1-035, Avenida Carlos Chagas Filho 373, Cidade Universitária, Ilha do Fundão, 21.941-902 Rio de Janeiro, RJ, Brazil
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41
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Nunes MP, Fortes B, Silva-Filho JL, Terra-Granado E, Santos L, Conde L, de Araújo Oliveira I, Freire-de-Lima L, Martins MV, Pinheiro AAS, Takyia CM, Freire-de-Lima CG, Todeschini AR, DosReis GA, Morrot A. Inhibitory effects of Trypanosoma cruzi sialoglycoproteins on CD4+ T cells are associated with increased susceptibility to infection. PLoS One 2013; 8:e77568. [PMID: 24204874 PMCID: PMC3810146 DOI: 10.1371/journal.pone.0077568] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Accepted: 09/03/2013] [Indexed: 01/16/2023] Open
Abstract
Background The Trypanosoma cruzi infection is associated with severe T cell unresponsiveness to antigens and mitogens characterized by decreased IL-2 synthesis. Trypanosoma cruzi mucin (Tc Muc) has been implicated in this phenomenom. These molecules contain a unique type of glycosylation consisting of several sialylated O-glycans linked to the protein backbone via N-acetylglucosamine residues. Methodology/Principal Findings In this study, we evaluated the ability of Tc Muc to modulate the activation of CD4+ T cells. Our data show that cross-linking of CD3 on naïve CD4+ T cells in the presence of Tc Muc resulted in the inhibition of both cytokine secretion and proliferation. We further show that the sialylated O-Linked Glycan residues from tc mucin potentiate the suppression of T cell response by inducing G1-phase cell cycle arrest associated with upregulation of mitogen inhibitor p27kip1. These inhibitory effects cannot be reversed by the addition of exogenous IL-2, rendering CD4+ T cells anergic when activated by TCR triggering. Additionally, in vivo administration of Tc Muc during T. cruzi infection enhanced parasitemia and aggravated heart damage. Analysis of recall responses during infection showed lower frequencies of IFN-γ producing CD4+ T cells in the spleen of Tc Muc treated mice, compared to untreated controls. Conclusions/Significance Our results indicate that Tc Muc mediates inhibitory efects on CD4+ T expansion and cytokine production, by blocking cell cycle progression in the G1 phase. We propose that the sialyl motif of Tc Muc is able to interact with sialic acid-binding Ig-like lectins (Siglecs) on CD4+ T cells, which may allow the parasite to modulate the immune system.
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Affiliation(s)
| | - Bárbara Fortes
- Institute of Microbiology, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - João Luiz Silva-Filho
- Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | | | | | | | - Isadora de Araújo Oliveira
- Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Leonardo Freire-de-Lima
- Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | | | - Ana Acacia Sá Pinheiro
- Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Christina Maeda Takyia
- Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | | | - Adriane Regina Todeschini
- Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - George Alexandre DosReis
- Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Alexandre Morrot
- Institute of Microbiology, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- * E-mail: (MPN); (AM)
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Esch KJ, Petersen CA. Transmission and epidemiology of zoonotic protozoal diseases of companion animals. Clin Microbiol Rev 2013; 26:58-85. [PMID: 23297259 PMCID: PMC3553666 DOI: 10.1128/cmr.00067-12] [Citation(s) in RCA: 168] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Over 77 million dogs and 93 million cats share our households in the United States. Multiple studies have demonstrated the importance of pets in their owners' physical and mental health. Given the large number of companion animals in the United States and the proximity and bond of these animals with their owners, understanding and preventing the diseases that these companions bring with them are of paramount importance. Zoonotic protozoal parasites, including toxoplasmosis, Chagas' disease, babesiosis, giardiasis, and leishmaniasis, can cause insidious infections, with asymptomatic animals being capable of transmitting disease. Giardia and Toxoplasma gondii, endemic to the United States, have high prevalences in companion animals. Leishmania and Trypanosoma cruzi are found regionally within the United States. These diseases have lower prevalences but are significant sources of human disease globally and are expanding their companion animal distribution. Thankfully, healthy individuals in the United States are protected by intact immune systems and bolstered by good nutrition, sanitation, and hygiene. Immunocompromised individuals, including the growing number of obese and/or diabetic people, are at a much higher risk of developing zoonoses. Awareness of these often neglected diseases in all health communities is important for protecting pets and owners. To provide this awareness, this review is focused on zoonotic protozoal mechanisms of virulence, epidemiology, and the transmission of pathogens of consequence to pet owners in the United States.
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CpG and interleukin-15 synergize to enhance IFN-γ production by activated CD8+ T cells. BIOMED RESEARCH INTERNATIONAL 2012; 2013:924023. [PMID: 23509806 PMCID: PMC3591192 DOI: 10.1155/2013/924023] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/17/2012] [Accepted: 08/06/2012] [Indexed: 11/23/2022]
Abstract
Interleukin-15 (IL-15) regulates the development and maintenance of memory CD8+ T cells. Paradoxically, we previously reported that IL-15 could enhance CD8+ T-cell responses to IL-12, a proinflammatory cytokine required for optimal priming of effector CD8+ T cells. To expand the physiological relevance of these findings, we tested IL-15 for its ability to enhance T-cell responses to bacterial CpG. Expectedly, CpG enhanced the production of IFN-γ by CD8+ T cells polyclonally activated with anti-CD3. However, addition of IL-15 to CpG-stimulated cultures led to a striking increase in IFN-γ production. The effect of CpG and IL-15 was also evident with CD8+ T cells recovered from mice infected with the parasite Trypanosoma cruzi (T. cruzi) and restimulated with antigen. The observed synergy between CpG and IL-15 occurred in an IL-12-dependent manner, and this effect could even be demonstrated in cocultures of activated CD8+ T cells and CD4+CD25+ regulatory T cells. Although IFN-γ was not essential for CpG-induced IL-12, the ability of CpG and IL-15 to act on CD8+ T cells required expression of the IFN-γ-inducible transcription factor T-bet. These data have important implications for development of vaccines and design of therapies to boost CD8+ T-cell responses to infectious agents and tumors.
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44
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Lasso P, Mesa D, Bolaños N, Cuéllar A, Guzmán F, Cucunuba Z, Rosas F, Velasco V, Thomas MC, López MC, González JM, Puerta CJ. Chagasic patients are able to respond against a viral antigen from influenza virus. BMC Infect Dis 2012; 12:198. [PMID: 22920436 PMCID: PMC3511223 DOI: 10.1186/1471-2334-12-198] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2011] [Accepted: 08/13/2012] [Indexed: 12/13/2022] Open
Abstract
Background Trypanosoma cruzi, the etiological agent of Chagas’ disease, is an obligate intracellular parasite which induces a CD8+ T cell immune response with secretion of cytokines and release of cytotoxic granules. Although an immune-suppressive effect of T. cruzi on the acute phase of the disease has been described, little is known about the capacity of CD8+ T cell from chronic chagasic patients to respond to a non-T. cruzi microbial antigen. Methods In the present paper, the frequency, phenotype and the functional activity of the CD8+ T cells specific from Flu-MP*, an influenza virus epitope, were determined in 13 chagasic patients and 5 healthy donors. Results The results show that Flu-MP* peptide specific CD8+ T cells were found with similar frequencies in both groups. In addition, Flu-MP* specific CD8+ T cells were distributed in the early or intermediate/late differentiation stages without showing enrichment of a specific sub-population. The mentioned Flu-MP* specific CD8+ T cells from chagasic patients were predominately TEM (CCR7- CD62L-), producing IL-2, IFNγ, CD107a/b and perforin, and did not present significant differences when compared with those from healthy donors. Conclusions Our results support the hypothesis that there is no CD8+ T cell nonspecific immune-suppression during chronic Chagas disease infection. Nonetheless, other viral antigens must be studied in order to confirm our findings.
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Affiliation(s)
- Paola Lasso
- Laboratorio de Parasitología Molecular, Pontificia Universidad Javeriana, Bogotá, Colombia
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Vasconcelos JR, Bruña–Romero O, Araújo AF, Dominguez MR, Ersching J, de Alencar BCG, Machado AV, Gazzinelli RT, Bortoluci KR, Amarante-Mendes GP, Lopes MF, Rodrigues MM. Pathogen-induced proapoptotic phenotype and high CD95 (Fas) expression accompany a suboptimal CD8+ T-cell response: reversal by adenoviral vaccine. PLoS Pathog 2012; 8:e1002699. [PMID: 22615561 PMCID: PMC3355083 DOI: 10.1371/journal.ppat.1002699] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2011] [Accepted: 03/29/2012] [Indexed: 12/03/2022] Open
Abstract
MHC class Ia-restricted CD8+ T cells are important mediators of the adaptive immune response against infections caused by intracellular microorganisms. Whereas antigen-specific effector CD8+ T cells can clear infection caused by intracellular pathogens, in some circumstances, the immune response is suboptimal and the microorganisms survive, causing host death or chronic infection. Here, we explored the cellular and molecular mechanisms that could explain why CD8+ T cell-mediated immunity during infection with the human protozoan parasite Trypanosoma cruzi is not optimal. For that purpose, we compared the CD8+ T-cell mediated immune responses in mice infected with T. cruzi or vaccinated with a recombinant adenovirus expressing an immunodominant parasite antigen. Several functional and phenotypic characteristics of specific CD8+ T cells overlapped. Among few exceptions was an accelerated expansion of the immune response in adenoviral vaccinated mice when compared to infected ones. Also, there was an upregulated expression of the apoptotic-signaling receptor CD95 on the surface of specific T cells from infected mice, which was not observed in the case of adenoviral-vaccinated mice. Most importantly, adenoviral vaccine provided at the time of infection significantly reduced the upregulation of CD95 expression and the proapoptotic phenotype of pathogen-specific CD8+ cells expanded during infection. In parallel, infected adenovirus-vaccinated mice had a stronger CD8 T-cell mediated immune response and survived an otherwise lethal infection. We concluded that a suboptimal CD8+ T-cell response is associated with an upregulation of CD95 expression and a proapoptotic phenotype. Both can be blocked by adenoviral vaccination. Killer lymphocytes are important mediators of the immunological resistance against infections caused by virus, bacteria and parasites. In some circumstances, however, these lymphocytes are unable to properly eliminate the microorganisms which survive, causing death or establishing chronic infections. The purpose of our study was to understand why these killer cells do not succeed during infection with a human protozoan parasite. For that purpose, we compared the immune responses in animals infected or vaccinated. Many characteristics of these killer cells were similar. Among few exceptions was an accelerated immune response in vaccinated animals when compared to infected ones. Also, we observed on the surface of the killer lymphocytes from infected, but not from vaccinated animals, an increased expression of a protein involved in signaling cell death. Most importantly, vaccine significantly reduced the higher expression of this cell-death receptor. In parallel, these animals had a stronger immune response and cured infection. We concluded that a deficient killer cell response observed during infection was associated with an upregulation of this cell-death receptor and it was changed by vaccination.
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Affiliation(s)
- José Ronnie Vasconcelos
- Centro de Terapia Celular e Molecular (CTCMol), Universidade Federal de São Paulo-Escola Paulista de Medicina, São Paulo, São Paulo, Brazil
- Departmento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo-Escola Paulista de Medicina, São Paulo, São Paulo, Brazil
| | - Oscar Bruña–Romero
- Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Adriano F. Araújo
- Centro de Terapia Celular e Molecular (CTCMol), Universidade Federal de São Paulo-Escola Paulista de Medicina, São Paulo, São Paulo, Brazil
- Departmento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo-Escola Paulista de Medicina, São Paulo, São Paulo, Brazil
| | - Mariana R. Dominguez
- Centro de Terapia Celular e Molecular (CTCMol), Universidade Federal de São Paulo-Escola Paulista de Medicina, São Paulo, São Paulo, Brazil
- Departmento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo-Escola Paulista de Medicina, São Paulo, São Paulo, Brazil
| | - Jonatan Ersching
- Centro de Terapia Celular e Molecular (CTCMol), Universidade Federal de São Paulo-Escola Paulista de Medicina, São Paulo, São Paulo, Brazil
- Departmento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo-Escola Paulista de Medicina, São Paulo, São Paulo, Brazil
| | - Bruna C. G. de Alencar
- Centro de Terapia Celular e Molecular (CTCMol), Universidade Federal de São Paulo-Escola Paulista de Medicina, São Paulo, São Paulo, Brazil
- Departmento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo-Escola Paulista de Medicina, São Paulo, São Paulo, Brazil
| | | | - Ricardo T. Gazzinelli
- Centro de Pesquisas René Rachou, FIOCRUZ, Belo Horizonte, Minas Gerais, Brazil
- Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Pampulha, Belo Horizonte, Minas Gerais, Brazil
- Division of Infectious Disease and Immunology, Department of Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Karina R. Bortoluci
- Centro de Terapia Celular e Molecular (CTCMol), Universidade Federal de São Paulo-Escola Paulista de Medicina, São Paulo, São Paulo, Brazil
- Departamento de Ciências Biológicas, Universidade Federal de São Paulo-Escola Paulista de Medicina, Diadema, São Paulo, Brazil
| | - Gustavo P. Amarante-Mendes
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, São Paulo, Brazil
| | - Marcela F. Lopes
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Mauricio M. Rodrigues
- Centro de Terapia Celular e Molecular (CTCMol), Universidade Federal de São Paulo-Escola Paulista de Medicina, São Paulo, São Paulo, Brazil
- Departmento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo-Escola Paulista de Medicina, São Paulo, São Paulo, Brazil
- * E-mail:
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Dominguez MR, Ersching J, Lemos R, Machado AV, Bruna-Romero O, Rodrigues MM, de Vasconcelos JRC. Re-circulation of lymphocytes mediated by sphingosine-1-phosphate receptor-1 contributes to resistance against experimental infection with the protozoan parasite Trypanosoma cruzi. Vaccine 2012; 30:2882-91. [PMID: 22381075 DOI: 10.1016/j.vaccine.2012.02.037] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2011] [Revised: 01/26/2012] [Accepted: 02/15/2012] [Indexed: 12/23/2022]
Abstract
T-cell mediated immune responses are critical for acquired immunity against infection by the intracellular protozoan parasite Trypanosoma cruzi. Despite its importance, it is currently unknown where protective T cells are primed and whether they need to re-circulate in order to exert their anti-parasitic effector functions. Here, we show that after subcutaneous challenge, CD11c(+)-dependent specific CD8(+) T-cell immune response to immunodominant parasite epitopes arises almost simultaneously in the draining lymph node (LN) and the spleen. However, until day 10 after infection, we observed a clear upregulation of activation markers only on the surface of CD11C(+)PDCA1(+) cells present in the LN and not in the spleen. Therefore, we hypothesized that CD8(+) T cells re-circulated rapidly from the LN to the spleen. We investigated this phenomenon by administering FTY720 to T. cruzi-infected mice to prevent egress of T cells from the LN by interfering specifically with signalling through sphingosine-1-phosphate receptor-1. In T. cruzi-infected mice receiving FTY720, CD8 T-cell immune responses were higher in the draining LN and significantly reduced in their spleen. Most importantly, FTY720 increased susceptibility to infection, as indicated by elevated parasitemia and accelerated mortality. Similarly, administration of FTY720 to mice genetically vaccinated with an immunodominant parasite antigen significantly reduced their protective immunity, as observed by the parasitemia and survival of vaccinated mice. We concluded that re-circulation of lymphocytes mediated by sphingosine-1-phosphate receptor-1 greatly contributes to acquired and vaccine-induced protective immunity against experimental infection with a human protozoan parasite.
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Affiliation(s)
- Mariana R Dominguez
- Centro de Terapia Celular e Molecular, Universidade Federal de São Paulo-Escola Paulista de Medicina, Brazil
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Pellegrini A, Guiñazu N, Giordanengo L, Cano RC, Gea S. The role of Toll-like receptors and adaptive immunity in the development of protective or pathological immune response triggered by the Trypanosoma cruzi protozoan. Future Microbiol 2011; 6:1521-33. [DOI: 10.2217/fmb.11.122] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Trypanosoma cruzi, the causal agent of Chagas disease, is an intracellular protozoan parasite that predominantly invades macrophages and cardiomyocytes, leading to persistent infection. Several members of the Toll-like receptor family are crucial for innate immunity to infection and are involved in maintaining tissue homeostasis. This review focuses on recent experimental findings of the innate and adaptive immune response in controlling the parasite and/or in generating heart and liver tissue injury. We also describe the importance of the host’s genetic background in the outcome of the disease and emphasize the importance of studying the response to specific parasite antigens. Understanding the dual participation of the immune response may contribute to the design of new therapies for Chagas disease.
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Affiliation(s)
- Andrea Pellegrini
- Inmunología, Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, CIBICI-CONICET, Universidad Nacional de Córdoba, Ciudad Universitaria, Haya de la Torre y Medina Allende S/N, Córdoba, 5000, Argentina
| | - Natalia Guiñazu
- Inmunología, Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, CIBICI-CONICET, Universidad Nacional de Córdoba, Ciudad Universitaria, Haya de la Torre y Medina Allende S/N, Córdoba, 5000, Argentina
| | - Laura Giordanengo
- Inmunología, Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, CIBICI-CONICET, Universidad Nacional de Córdoba, Ciudad Universitaria, Haya de la Torre y Medina Allende S/N, Córdoba, 5000, Argentina
| | - Roxana Carolina Cano
- Inmunología, Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, CIBICI-CONICET, Universidad Nacional de Córdoba, Ciudad Universitaria, Haya de la Torre y Medina Allende S/N, Córdoba, 5000, Argentina
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48
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A soluble factor from Trypanosoma cruzi inhibits transforming growth factor-ß-induced MAP kinase activation and gene expression in dermal fibroblasts. PLoS One 2011; 6:e23482. [PMID: 21931601 PMCID: PMC3169535 DOI: 10.1371/journal.pone.0023482] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2011] [Accepted: 07/18/2011] [Indexed: 02/04/2023] Open
Abstract
The protozoan parasite Trypanosoma cruzi, which causes human Chagas' disease, exerts a variety of effects on host extracellular matrix (ECM) including proteolytic degradation of collagens and dampening of ECM gene expression. Exposure of primary human dermal fibroblasts to live infective T. cruzi trypomastigotes or their shed/secreted products results in a rapid down-regulation of the fibrogenic genes collagenIα1, fibronectin and connective tissue growth factor (CTGF/CCN2). Here we demonstrate the ability of a secreted/released T. cruzi factor to antagonize ctgf/ccn2 expression in dermal fibroblasts in response to TGF-ß, lysophosphatidic acid or serum, where agonist-induced phosphorylation of the mitogen-activated protein (MAP) kinases Erk1/2, p38 and JNK was also inhibited. Global analysis of gene expression in dermal fibroblasts identified a discrete subset of TGF-ß-inducible genes involved in cell proliferation, wound repair, and immune regulation that are inhibited by T. cruzi secreted/released factors, where the genes exhibiting the highest sensitivity to T. cruzi are known to be regulated by MAP kinase-activated transcription factors. Consistent with this observation, the Ets-family transcription factor binding site in the proximal promoter region of the ctgf/ccn2 gene (−91 bp to −84 bp) was shown to be required for T. cruzi-mediated down-regulation of ctgf/ccn2 reporter expression. The cumulative data suggest a model in which T. cruzi-derived molecules secreted/released early in the infective process dampen MAP kinase signaling and the activation of transcription factors that regulate expression of fibroblast genes involved in wound repair and tissue remodelling, including ctgf/ccn2. These findings have broader implications for local modulation of ECM synthesis/remodelling by T. cruzi during the early establishment of infection in the mammalian host and highlight the potential for pathogen-derived molecules to be exploited as tools to modulate the fibrogenic response.
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Aoki MP, Carrera-Silva EA, Cuervo H, Fresno M, Gironès N, Gea S. Nonimmune Cells Contribute to Crosstalk between Immune Cells and Inflammatory Mediators in the Innate Response to Trypanosoma cruzi Infection. J Parasitol Res 2011; 2012:737324. [PMID: 21869919 PMCID: PMC3159004 DOI: 10.1155/2012/737324] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2011] [Accepted: 06/19/2011] [Indexed: 01/22/2023] Open
Abstract
Chagas myocarditis, which is caused by infection with the intracellular parasite Trypanosoma cruzi, remains the major infectious heart disease worldwide. Innate recognition through toll-like receptors (TLRs) on immune cells has not only been revealed to be critical for defense against T. cruzi but has also been involved in triggering the pathology. Subsequent studies revealed that this parasite activates nucleotide-binding oligomerization domain- (NOD-)like receptors and several particular transcription factors in TLR-independent manner. In addition to professional immune cells, T. cruzi infects and resides in different parenchyma cells. The innate receptors in nonimmune target tissues could also have an impact on host response. Thus, the outcome of the myocarditis or the inflamed liver relies on an intricate network of inflammatory mediators and signals given by immune and nonimmune cells. In this paper, we discuss the evidence of innate immunity to the parasite developed by the host, with emphasis on the crosstalk between immune and nonimmune cell responses.
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Affiliation(s)
- Maria Pilar Aoki
- Departamento de Bioquímica Clínica, Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba 5000, Argentina
| | - Eugenio Antonio Carrera-Silva
- Departamento de Bioquímica Clínica, Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba 5000, Argentina
- Department of Immunobiology, School of Medicine, Yale University, New Haven, CT 06520, USA
| | - Henar Cuervo
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas (CSIC), Universidad Autónoma de Madrid (UAM), Cantoblanco, Madrid 28049, Spain
| | - Manuel Fresno
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas (CSIC), Universidad Autónoma de Madrid (UAM), Cantoblanco, Madrid 28049, Spain
| | - Núria Gironès
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas (CSIC), Universidad Autónoma de Madrid (UAM), Cantoblanco, Madrid 28049, Spain
| | - Susana Gea
- Departamento de Bioquímica Clínica, Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba 5000, Argentina
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50
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Oral exposure to Trypanosoma cruzi elicits a systemic CD8⁺ T cell response and protection against heterotopic challenge. Infect Immun 2011; 79:3397-406. [PMID: 21628516 DOI: 10.1128/iai.01080-10] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Trypanosoma cruzi infects millions of people in Latin America and often leads to the development of Chagas disease. T. cruzi infection can be acquired at or near the bite site of the triatomine vector, but per os infection is also a well-documented mode of transmission, as evidenced by recent microepidemics of acute Chagas disease attributed to the consumption of parasite-contaminated foods and liquids. It would also be convenient to deliver vaccines for T. cruzi by the oral route, particularly live parasite vaccines intended for the immunization of reservoir hosts. For these reasons, we were interested in better understanding immunity to T. cruzi following oral infection or oral vaccination, knowing that the route of infection and site of antigen encounter can have substantial effects on the ensuing immune response. Here, we show that the route of infection does not alter the ability of T. cruzi to establish infection in muscle tissue nor does it impair the generation of a robust CD8(+) T cell response. Importantly, oral vaccination with attenuated parasites provides protection against wild-type (WT) T. cruzi challenge. These results strongly support the development of whole-organism-based vaccines targeting reservoir species as a means to alleviate the burden of Chagas disease in affected regions.
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