1
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Cardoso-Miguel MDRD, Bürgel PH, de Castro RJA, Marina CL, de Oliveira SA, Albuquerque P, Silva-Pereira I, Bocca AL, Tavares AH. Dectin-2 is critical for phagocyte function and resistance to Paracoccidioides brasiliensis in mice. Med Mycol 2023; 61:myad117. [PMID: 37960963 DOI: 10.1093/mmy/myad117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Revised: 08/11/2023] [Accepted: 11/11/2023] [Indexed: 11/15/2023] Open
Abstract
Germline-encoded pattern recognition receptors, particularly C-type lectin receptors (CLRs), are essential for phagocytes to sense invading fungal cells. Among CLRs, Dectin-2 (encoded by Clec4n) plays a critical role in the antifungal immune response as it recognizes high-mannose polysaccharides on the fungal cell wall, triggering phagocyte functional activities and ultimately determining adaptive responses. Here, we assessed the role of Dectin-2 on the course of primary Paracoccidioides brasiliensis systemic infection in mice with Dectin-2-targeted deletion. Paracoccidioides brasiliensis constitutes the principal etiologic agent of paracoccidioidomycosis, the most prominent invasive mycosis in Latin American countries. The deficiency of Dectin-2 resulted in shortened survival rates, high lung fungal burden, and increased lung pathology in mice infected with P. brasiliensis. Consistently, dendritic cells (DCs) from mice lacking Dectin-2 infected ex vivo with P. brasiliensis showed impaired secretion of several proinflammatory and regulatory cytokines, including TNF-α, IL-1β, IL-6, and IL-10. Additionally, when cocultured with splenic lymphocytes, DCs were less efficient in promoting a type 1 cytokine pattern secretion (i.e., IFN-γ). In macrophages, Dectin-2-mediated signaling was required to ensure phagocytosis and fungicidal activity associated with nitric oxide production. Overall, Dectin-2-mediated signaling is critical to promote host protection against P. brasiliensis infection, and its exploitation might lead to the development of new vaccines and immunotherapeutic approaches.
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Affiliation(s)
- Mariana de Resende Damas Cardoso-Miguel
- Graduate Program in Microbial Biology, Department of Cell Biology, Institute of Biological Sciences, University of Brasília, Brasília, DF, Brazil
- Department of Cell Biology, Laboratory of Applied Immunology, Institute of Biological Sciences, University of Brasília, Brasília, DF, Brazil
| | - Pedro Henrique Bürgel
- Graduate Program in Microbial Biology, Department of Cell Biology, Institute of Biological Sciences, University of Brasília, Brasília, DF, Brazil
- Department of Cell Biology, Laboratory of Applied Immunology, Institute of Biological Sciences, University of Brasília, Brasília, DF, Brazil
| | - Raffael Júnio Araújo de Castro
- Department of Cell Biology, Laboratory of Applied Immunology, Institute of Biological Sciences, University of Brasília, Brasília, DF, Brazil
| | - Clara Luna Marina
- Department of Cell Biology, Laboratory of Applied Immunology, Institute of Biological Sciences, University of Brasília, Brasília, DF, Brazil
| | - Stephan Alberto de Oliveira
- Department of Cell Biology, Laboratory of Applied Immunology, Institute of Biological Sciences, University of Brasília, Brasília, DF, Brazil
| | - Patrícia Albuquerque
- Graduate Program in Microbial Biology, Department of Cell Biology, Institute of Biological Sciences, University of Brasília, Brasília, DF, Brazil
- Department of Cell Biology, Laboratory of Molecular Biology of Pathogenic Fungi, University of Brasília, Brasília, DF, Brazil
- Laboratory of Microorganism, Faculty of Ceilândia, University of Brasília, Brasília, DF, Brazil
| | - Ildinete Silva-Pereira
- Department of Cell Biology, Laboratory of Molecular Biology of Pathogenic Fungi, University of Brasília, Brasília, DF, Brazil
| | - Anamélia Lorenzetti Bocca
- Department of Cell Biology, Laboratory of Applied Immunology, Institute of Biological Sciences, University of Brasília, Brasília, DF, Brazil
| | - Aldo Henrique Tavares
- Graduate Program in Microbial Biology, Department of Cell Biology, Institute of Biological Sciences, University of Brasília, Brasília, DF, Brazil
- Laboratory of Microorganism, Faculty of Ceilândia, University of Brasília, Brasília, DF, Brazil
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2
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Hahn RC, Hagen F, Mendes RP, Burger E, Nery AF, Siqueira NP, Guevara A, Rodrigues AM, de Camargo ZP. Paracoccidioidomycosis: Current Status and Future Trends. Clin Microbiol Rev 2022; 35:e0023321. [PMID: 36074014 PMCID: PMC9769695 DOI: 10.1128/cmr.00233-21] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Paracoccidioidomycosis (PCM), initially reported in 1908 in the city of São Paulo, Brazil, by Adolpho Lutz, is primarily a systemic and neglected tropical mycosis that may affect individuals with certain risk factors around Latin America, especially Brazil. Paracoccidioides brasiliensis sensu stricto, a classical thermodimorphic fungus associated with PCM, was long considered to represent a monotypic taxon. However, advances in molecular taxonomy revealed several cryptic species, including Paracoccidioides americana, P. restrepiensis, P. venezuelensis, and P. lutzii, that show a preference for skin and mucous membranes, lymph nodes, and respiratory organs but can also affect many other organs. The classical diagnosis of PCM benefits from direct microscopy culture-based, biochemical, and immunological assays in a general microbiology laboratory practice providing a generic identification of the agents. However, molecular assays should be employed to identify Paracoccidioides isolates to the species level, data that would be complemented by epidemiological investigations. From a clinical perspective, all probable and confirmed cases should be treated. The choice of treatment and its duration must be considered, along with the affected organs, process severity, history of previous treatment failure, possibility of administering oral medication, associated diseases, pregnancy, and patient compliance with the proposed treatment regimen. Nevertheless, even after appropriate treatment, there may be relapses, which generally occur 5 years after the apparent cure following treatment, and also, the mycosis may be confused with other diseases. This review provides a comprehensive and critical overview of the immunopathology, laboratory diagnosis, clinical aspects, and current treatment of PCM, highlighting current issues in the identification, treatment, and patient follow-up in light of recent Paracoccidioides species taxonomic developments.
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Affiliation(s)
- Rosane Christine Hahn
- Medical Mycology Laboratory/Investigation, Faculty of Medicine, Federal University of Mato Grosso, Cuiabá, Mato Grosso, Brazil
- Júlio Muller Hospital, EBSERH, Cuiabá, Mato Grosso, Brazil
| | - Ferry Hagen
- Westerdijk Fungal Biodiversity Institute, Utrecht, The Netherlands
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands
- Institute for Biodiversity and Ecosystem Dynamics (IBED), University of Amsterdam, Amsterdam, The Netherlands
| | - Rinaldo Poncio Mendes
- Faculdade de Medicina de Botucatu, São Paulo State University (UNESP), Botucatu, São Paulo, Brazil
- Faculdade de Medicina, Federal University of Mato Grosso do Sul (UFMS), Campo Grande, Mato Grosso do Sul, Brazil
| | - Eva Burger
- Department of Microbiology and Immunology, Federal University of Alfenasgrid.411180.d (UNIFAL), Alfenas, Minas Gerais, Brazil
| | - Andreia Ferreira Nery
- Medical Mycology Laboratory/Investigation, Faculty of Medicine, Federal University of Mato Grosso, Cuiabá, Mato Grosso, Brazil
- Júlio Muller Hospital, EBSERH, Cuiabá, Mato Grosso, Brazil
| | - Nathan Pereira Siqueira
- Medical Mycology Laboratory/Investigation, Faculty of Medicine, Federal University of Mato Grosso, Cuiabá, Mato Grosso, Brazil
| | - Armando Guevara
- Medical Mycology Laboratory/Investigation, Faculty of Medicine, Federal University of Mato Grosso, Cuiabá, Mato Grosso, Brazil
| | - Anderson Messias Rodrigues
- Laboratory of Emerging Fungal Pathogens, Department of Microbiology, Immunology, and Parasitology, Federal University of São Paulo (UNIFESP), São Paulo, São Paulo, Brazil
- Department of Medicine, Discipline of Infectious Diseases, Federal University of São Paulo (UNIFESP), São Paulo, São Paulo, Brazil
| | - Zoilo Pires de Camargo
- Laboratory of Emerging Fungal Pathogens, Department of Microbiology, Immunology, and Parasitology, Federal University of São Paulo (UNIFESP), São Paulo, São Paulo, Brazil
- Department of Medicine, Discipline of Infectious Diseases, Federal University of São Paulo (UNIFESP), São Paulo, São Paulo, Brazil
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3
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Is the production of reactive oxygen and nitrogen species by macrophages associated with better infectious control in female mice with experimentally disseminated and pulmonary mucormycosis? PLoS One 2022; 17:e0270071. [PMID: 36520787 PMCID: PMC9754262 DOI: 10.1371/journal.pone.0270071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Accepted: 11/08/2022] [Indexed: 12/23/2022] Open
Abstract
Different levels of resistance against Rhizopus oryzae infection have been observed between inbred (BALB/c) and outbred (Swiss) mice and are associated with the genetic background of each mouse strain. Considering that macrophages play an important role in host resistance to Rhizopus species, we used different infectious outcomes observed in experimental mucormycosis to identify the most efficient macrophage response pattern against R. oryzae in vitro and in vivo. For this, we compared BALB/c and Swiss macrophage activity before and after intravenous or intratracheal R. oryzae infections. The production of hydrogen peroxide (H2O2) and nitric oxide (NO) was determined in cultures of peritoneal (PMΦ) or alveolar macrophages (AMΦ) challenged with heat-killed spores of R. oryzae. The levels of tumor necrosis factor-alpha (TNF-α) and interleukin-10 (IL-10) were measured to confirm our findings. Naïve PMΦ from female BALB/c mice showed increased production of H2O2, TNF-α, and IL-10 in the presence of heat-killed spores of R. oryzae. Naïve PMΦ from female Swiss mice were less responsive. Naïve AMΦ from the two strains of female mice were less reactive to heat-killed spores of R. oryzae than PMΦ. After 30 days of R. oryzae intravenous infection, lower fungal load in spleen from BALB/c mice was accompanied by higher production of H2O2 by PMΦ compared with Swiss mice. In contrast, AMΦ from BALB/c mice showed higher production of NO, TNF-α, and IL-10 after 7 days of intratracheal infection. The collective findings reveal that, independent of the female mouse strain, PMΦ is more reactive against R. oryzae upon first contact than AMΦ. In addition, increased PMΦ production of H2O2 at the end of disseminated infection is accompanied by better fungal clearance in resistant (BALB/c) mice. Our findings further the understanding of the parasite-host relationship in mucormycosis.
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4
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de Oliveira SAM, Reis JN, Catão E, Amaral AC, Souza ACO, Ribeiro AM, Faccioli LH, Carneiro FP, Marina CLF, Bürgel PH, Fernandes L, Tavares AH, Bocca AL. β2 Integrin-Mediated Susceptibility to Paracoccidioides brasiliensis Experimental Infection in Mice. Front Cell Infect Microbiol 2021; 11:622899. [PMID: 33796477 PMCID: PMC8007971 DOI: 10.3389/fcimb.2021.622899] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 01/25/2021] [Indexed: 11/13/2022] Open
Abstract
The earliest interaction between macrophages and Paracoccidioides brasiliensis is particularly important in paracoccidioidomycosis (PCM) progression, and surface proteins play a central role in this process. The present study investigated the contribution of β2 integrin in P. brasiliensis-macrophage interaction and PCM progression. We infected β2-low expression (CD18low) and wild type (WT) mice with P. brasiliensis 18. Disease progression was evaluated for fungal burden, lung granulomatous lesions, nitrate levels, and serum antibody production. Besides, the in vitro capacity of macrophages to internalize and kill fungal yeasts was investigated. Our results revealed that CD18low mice infected with Pb18 survived during the time analyzed; their lungs showed fewer granulomas, a lower fungal load, lower levels of nitrate, and production of high levels of IgG1 in comparison to WT animals. Our results revealed that in vitro macrophages from CD18low mice slowly internalized yeast cells, showing a lower fungal burden compared to WT cells. The migration capacity of macrophages was compromised and showed a higher intensity in the lysosome signal when compared with WT mice. Our data suggest that β2 integrins play an important role in fungal survival inside macrophages, and once phagocytosed, the macrophage may serve as a protective environment for P. brasiliensis.
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Affiliation(s)
- Stephan Alberto Machado de Oliveira
- Molecular Pathology Graduation Course, Faculty of Medicine, University of Brasilia, Brasilia, Brazil.,Department of Cell Biology, Institute of Biological Sciences, University of Brasilia, Brasilia, Brazil
| | - Janayna Nunes Reis
- Molecular Pathology Graduation Course, Faculty of Medicine, University of Brasilia, Brasilia, Brazil
| | - Elisa Catão
- Department of Cell Biology, Institute of Biological Sciences, University of Brasilia, Brasilia, Brazil
| | - Andre Correa Amaral
- Institute of Tropical Pathology and Public Health, Federal University of Goiás, Goiania, Brazil
| | - Ana Camila Oliveira Souza
- Molecular Pathology Graduation Course, Faculty of Medicine, University of Brasilia, Brasilia, Brazil
| | - Alice Melo Ribeiro
- Department of Cell Biology, Institute of Biological Sciences, University of Brasilia, Brasilia, Brazil
| | - Lúcia Helena Faccioli
- Faculty of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil
| | | | - Clara Luna Freitas Marina
- Molecular Biology Graduation Course, Institute of Biological Sciences, University of Brasilia, Brasilia, Brazil
| | - Pedro Henrique Bürgel
- Molecular Biology Graduation Course, Institute of Biological Sciences, University of Brasilia, Brasilia, Brazil
| | | | | | - Anamelia Lorenzetti Bocca
- Molecular Pathology Graduation Course, Faculty of Medicine, University of Brasilia, Brasilia, Brazil.,Department of Cell Biology, Institute of Biological Sciences, University of Brasilia, Brasilia, Brazil.,Molecular Biology Graduation Course, Institute of Biological Sciences, University of Brasilia, Brasilia, Brazil
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5
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Burger E. Paracoccidioidomycosis Protective Immunity. J Fungi (Basel) 2021; 7:jof7020137. [PMID: 33668671 PMCID: PMC7918802 DOI: 10.3390/jof7020137] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 02/02/2021] [Accepted: 02/04/2021] [Indexed: 12/26/2022] Open
Abstract
Protective immunity against Paracoccidioides consists of a stepwise activation of numerous effector mechanisms that comprise many cellular and soluble components. At the initial phase of non-specific innate immunity, resistance against Paracoccidioides comes from phagocytic polymorphonuclear neutrophils, natural killer (NK) cells and monocytes, supplemented by soluble factors such as cytokines and complement system components. Invariant receptors (Toll-like receptors (TLRs), Dectins) which are present in cells of the immune system, detect patterns present in Paracoccidioides (but not in the host) informing the hosts cells that there is an infection in progress, and that the acquired immunity must be activated. The role of components involved in the innate immunity of paracoccidioidomycosis is herein presented. Humoral immunity, represented by specific antibodies which control the fungi in the blood and body fluids, and its role in paracoccidioidomycosis (which was previously considered controversial) is also discussed. The protective mechanisms (involving various components) of cellular immunity are also discussed, covering topics such as: lysis by activated macrophages and cytotoxic T lymphocytes, the participation of lytic products, and the role of cytokines secreted by T helper lymphocytes in increasing the efficiency of Paracoccidioides, lysis.
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Affiliation(s)
- Eva Burger
- Department of Microbiology and Immunology, Universidade Federal de Alfenas, Alfenas 37130-001, Brazil
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6
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Silva GS, Silva DA, Guilhelmelli F, Jerônimo MS, Cardoso-Miguel MRD, Bürgel PH, Castro RJA, de Oliveira SAM, Silva-Pereira I, Bocca AL, Tavares AH. Zymosan enhances in vitro phagocyte function and the immune response of mice infected with Paracoccidioides brasiliensis. Med Mycol 2021; 59:749-762. [PMID: 33550415 DOI: 10.1093/mmy/myaa117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 11/26/2020] [Accepted: 12/24/2020] [Indexed: 11/13/2022] Open
Abstract
Paracoccidioides brasiliensis is the major etiologic agent of Paracoccidioidomycosis (PCM), the most frequent human deep mycosis in Latin America. It is proposed that masking of β-glucan in P. brasiliensis cell wall is a critical virulence factor that contributes to the development of a chronic disease characterized by a long period of treatment, which is usually toxic. In this context, the search for immunomodulatory agents for therapeutic purposes is highly desirable. One strategy is to use pattern recognition receptors (PRRs) ligands to stimulate the immune response mediated by phagocytes. Here, we sought to evaluate if Zymosan, a β-glucan-containing ligand of the PRRs Dectin-1/TLR-2, would enhance phagocyte function and the immune response of mice challenged with P. brasiliensis. Dendritic cells (DCs) infected with P. brasiliensis and treated with Zymosan showed improved secretion of several proinflammatory cytokines and expression of maturation markers. In addition, when cocultured with splenic lymphocytes, these cells induced the production of a potential protective type 1 and 17 cytokine patterns. In macrophages, Zymosan ensued a significant fungicidal activity associated with nitric oxide production and phagolysosome acidification. Importantly, we observed a protective effect of Zymosan-primed DCs delivered intranasally in experimental pulmonary PCM. Overall, our findings support the potential use of β-glucan-containing compounds such as Zymosan as an alternative or complementary antifungal therapy. LAY SUMMARY We report for the first time that Paracoccidioides brasiliensis-infected phagocytes treated with Zymosan (cell wall extract from bakers' yeast) show enhanced cytokine production, maturation, and fungal killing. Also, Zymosan-primed phagocytes induce a protective immune response in infected mice.
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Affiliation(s)
- G S Silva
- Graduate Program in Molecular Pathology, Faculty of Medicine, University of Brasília, UnB, Brasília, DF, Brazil.,Faculty of Ceilândia, University of Brasília, UnB, Brasília, DF, Brazil
| | - D A Silva
- Faculty of Ceilândia, University of Brasília, UnB, Brasília, DF, Brazil
| | - F Guilhelmelli
- Laboratory of Molecular Biology of Pathogenic Fungi. Department of Cell Biology, Institute of Biological Sciences, University of Brasília, Brasília, Brazil
| | - M S Jerônimo
- Laboratory of Applied Immunology, Department of Cell Biology, Institute of Biological Sciences, University of Brasília, UnB, Brasília, DF, Brazil
| | - M R D Cardoso-Miguel
- Graduate Program in Microbial Biology, Department of Cell Biology, Institute of Biological Sciences, University of Brasília, UnB, Brasília, DF, Brazil
| | - P H Bürgel
- Laboratory of Applied Immunology, Department of Cell Biology, Institute of Biological Sciences, University of Brasília, UnB, Brasília, DF, Brazil.,Graduate Program in Microbial Biology, Department of Cell Biology, Institute of Biological Sciences, University of Brasília, UnB, Brasília, DF, Brazil
| | - R J A Castro
- Laboratory of Applied Immunology, Department of Cell Biology, Institute of Biological Sciences, University of Brasília, UnB, Brasília, DF, Brazil
| | - S A M de Oliveira
- Laboratory of Applied Immunology, Department of Cell Biology, Institute of Biological Sciences, University of Brasília, UnB, Brasília, DF, Brazil
| | - I Silva-Pereira
- Laboratory of Molecular Biology of Pathogenic Fungi. Department of Cell Biology, Institute of Biological Sciences, University of Brasília, Brasília, Brazil
| | - A L Bocca
- Laboratory of Applied Immunology, Department of Cell Biology, Institute of Biological Sciences, University of Brasília, UnB, Brasília, DF, Brazil
| | - A H Tavares
- Faculty of Ceilândia, University of Brasília, UnB, Brasília, DF, Brazil
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7
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Updates in Paracoccidioides Biology and Genetic Advances in Fungus Manipulation. J Fungi (Basel) 2021; 7:jof7020116. [PMID: 33557381 PMCID: PMC7915485 DOI: 10.3390/jof7020116] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 01/30/2021] [Accepted: 02/02/2021] [Indexed: 12/28/2022] Open
Abstract
The dimorphic fungi of the Paracoccidioides genus are the causative agents of paracoccidioidomycosis (PCM). This disease is endemic in Latin America and primarily affects workers in rural areas. PCM is considered a neglected disease, despite being a disabling disease that has a notable impact on the public health system. Paracoccidioides spp. are thermally dimorphic fungi that present infective mycelia at 25 °C and differentiate into pathogenic yeast forms at 37 °C. This transition involves a series of morphological, structural, and metabolic changes which are essential for their survival inside hosts. As a pathogen, the fungus is subjected to several varieties of stress conditions, including the host immune response, which involves the production of reactive nitrogen and oxygen species, thermal stress due to temperature changes during the transition, pH alterations within phagolysosomes, and hypoxia inside granulomas. Over the years, studies focusing on understanding the establishment and development of PCM have been conducted with several limitations due to the low effectiveness of strategies for the genetic manipulation of Paracoccidioides spp. This review describes the most relevant biological features of Paracoccidioides spp., including aspects of the phylogeny, ecology, stress response, infection, and evasion mechanisms of the fungus. We also discuss the genetic aspects and difficulties of fungal manipulation, and, finally, describe the advances in molecular biology that may be employed in molecular research on this fungus in the future.
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8
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Pulmonary paracoccidioidomycosis in AhR deficient hosts is severe and associated with defective Treg and Th22 responses. Sci Rep 2020; 10:11312. [PMID: 32647342 PMCID: PMC7347857 DOI: 10.1038/s41598-020-68322-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Accepted: 06/11/2020] [Indexed: 12/20/2022] Open
Abstract
AhR is a ligand-activated transcription factor that plays an important role in the innate and adaptive immune responses. In infection models, it has been associated with host responses that promote or inhibit disease progression. In pulmonary paracoccidioidomycosis, a primary fungal infection endemic in Latin America, immune protection is mediated by Th1/Th17 cells and disease severity with predominant Th2/Th9/Treg responses. Because of its important role at epithelial barriers, we evaluate the role of AhR in the outcome of a pulmonary model of paracoccidioidomycosis. AhR−/− mice show increased fungal burdens, enhanced tissue pathology and mortality. During the infection, AhR−/− mice have more pulmonary myeloid cells with activated phenotype and reduced numbers expressing indoleamine 2,3 dioxygenase 1. AhR-deficient lungs have altered production of cytokines and reduced numbers of innate lymphoid cells (NK, ILC3 and NCR IL-22). The lungs of AhR−/− mice showed increased presence Th17 cells concomitant with reduced numbers of Th1, Th22 and Foxp3+ Treg cells. Furthermore, treatment of infected WT mice with an AhR-specific antagonist (CH223191) reproduced the main findings obtained in AhR−/− mice. Collectively our data demonstrate that in pulmonary paracoccidioidomycosis AhR controls fungal burden and excessive tissue inflammation and is a possible target for antifungal therapy.
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9
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Riaz MS, Kaur A, Shwayat SN, Behboudi S, Kishore U, Pathan AA. Dissecting the Mechanism of Intracellular Mycobacterium smegmatis Growth Inhibition by Platelet Activating Factor C-16. Front Microbiol 2020; 11:1046. [PMID: 32587578 PMCID: PMC7297918 DOI: 10.3389/fmicb.2020.01046] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Accepted: 04/27/2020] [Indexed: 11/15/2022] Open
Abstract
Mycobacterium tuberculosis (M.tb) infection results in approximately 1.3 million human deaths each year. M.tb resides primarily inside macrophages, and maintains persistent infection. In response to infection and inflammation, platelet activating factor C-16 (PAF C-16), a phospholipid compound, is released by various cells including neutophils and monocytes. We have recently shown that PAF C-16 can directly inhibit the growth of two representative non-pathogenic mycobacteria, Mycobacterium bovis BCG and Mycobacterium smegmatis (M. smegmatis), by damaging the bacterial cell membrane. Here, we have examined the effect of PAF C-16 on M. smegmatis residing within macrophages, and identified mechanisms involved in their growth inhibitory function. Our results demonstrated that exogenous PAF C-16 inhibited the growth of M. smegmatis inside phagocytic cells of monocytic cell line, THP-1; this effect was partially blocked by PAF receptor antagonists, suggesting the involvement of PAF receptor-mediated signaling pathways. Arachidonic acid, a downstream metabolite of PAF C-16 signaling pathway, directly inhibited the growth of M. smegmatis in vitro. Moreover, the inhibition of phospholipase C and phospholipase A2 activities, involved in PAF C-16 signaling pathway, increased survival of intracellular M. smegmatis. Interestingly, we also observed that inhibition of inducible nitric oxide synthase (iNOS) enzyme and antibody-mediated neutralization of TNF-α partially mitigated the intracellular growth inhibitory effect of PAF C-16. Use of a number of PAF C-16 structural analogs, including Lyso-PAF, 2-O-methyl PAF, PAF C-18 and Hexanolamino PAF, revealed that the presence of acetyl group (CH3CO) at sn-2 position of the glycerol backbone of PAF is important for the intracellular growth inhibition activity against M. smegmatis. Taken together, these results suggest that exogenous PAF C-16 treatment inhibits intracellular M. smegmatis growth, at least partially, in a nitric oxide and TNF-α dependent manner.
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Affiliation(s)
- Muhammad Suleman Riaz
- Division of Biosciences, College of Health and Life Sciences, Brunel University London, Uxbridge, United Kingdom.,Department of Biotechnology, Abdul Wali Khan University, Mardan, Pakistan
| | - Anuvinder Kaur
- Division of Biosciences, College of Health and Life Sciences, Brunel University London, Uxbridge, United Kingdom
| | - Suha Nadim Shwayat
- Division of Biosciences, College of Health and Life Sciences, Brunel University London, Uxbridge, United Kingdom
| | - Shahriar Behboudi
- The Pirbright Institute, Woking, United Kingdom.,School of Veterinary Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, United Kingdom
| | - Uday Kishore
- Division of Biosciences, College of Health and Life Sciences, Brunel University London, Uxbridge, United Kingdom
| | - Ansar Ahmed Pathan
- Division of Biosciences, College of Health and Life Sciences, Brunel University London, Uxbridge, United Kingdom
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10
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Ketelut-Carneiro N, Souza COS, Benevides L, Gardinassi LG, Silva MC, Tavares LA, Zamboni DS, Silva JS. Caspase-11-dependent IL-1α release boosts Th17 immunity against Paracoccidioides brasiliensis. PLoS Pathog 2019; 15:e1007990. [PMID: 31425553 PMCID: PMC6715237 DOI: 10.1371/journal.ppat.1007990] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2019] [Revised: 08/29/2019] [Accepted: 07/18/2019] [Indexed: 12/22/2022] Open
Abstract
The granulomatous lesion resulting from infection with the fungus Paracoccidioides brasiliensis is characterized by a compact aggregate of mature cells, surrounded by a fibroblast- and collagen-rich content. Granuloma formation requires signaling elicited by inflammatory molecules such as members of the interleukin-1 family. Two members of this family have been thoroughly studied, namely IL-1α and IL-1β. In this study, we addressed the mechanisms underlying IL-1α secretion and its functional role on the host resistance to fungal infection. We found that, the expression of caspase-11 triggered by P. brasiliensis infection of macrophages depends on IFN-β production, because its inhibition reduced procaspase-11 levels. Curiously, caspase-11 deficiency did not impair IL-1β production, however caspase-11 was required for a rapid pore-mediated cell lysis. The plasma membrane rupture facilitated the release of IL-1α, which was necessary to induce NO production and restrict fungal replication. Furthermore, P. brasiliensis-infected macrophages required IL-1α to produce optimal levels of IL-6, a major component of Th17 lymphocyte differentiation. Indeed, IL-1α deficiency accounted for a significant reduction of Th17 lymphocytes in lungs of infected mice, correlating with diminished neutrophil infiltration in the lungs. Strikingly, we identified that IL-1α directly reprograms the transcriptional profile of Th17-committed lymphocytes, increasing cellular proliferation, as for boosting IL-17 production by these cells. Beyond neutrophil chemotaxis in vivo, IL-17 also amplified IL-1α production by infected macrophages in vitro, endorsing a critical amplification loop of the inflammatory response. Therefore, our data suggest that the IFN-β/caspase-11/IL-1α pathway shapes a protective antifungal Th17 immunity, revealing a molecular mechanism underlying the cross-talk between innate and adaptive immunity.
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Affiliation(s)
- Natália Ketelut-Carneiro
- Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Camila Oliveira Silva Souza
- Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Luciana Benevides
- Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Luiz Gustavo Gardinassi
- Department of Clinical Analyses, Toxicology and Food Science, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Maria Cláudia Silva
- Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Lucas Alves Tavares
- Department of Cell Biology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Dario Simões Zamboni
- Department of Cell Biology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - João Santana Silva
- Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
- Fiocruz-Bi-Institutional Translational Medicine Project, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
- * E-mail:
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11
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de Sá NP, Cisalpino PS, Bertollo CM, Santos PC, Rosa CA, de Souza DDG, Barbeira PJS, Alves TMDA, Zani CL, Johann S. Thiosemicarbazone of lapachol acts on cell membrane in Paracoccidioides brasiliensis. Med Mycol 2019; 57:332-339. [PMID: 29945180 DOI: 10.1093/mmy/myy045] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2017] [Revised: 04/23/2018] [Indexed: 11/13/2022] Open
Abstract
Paracoccidioidomycosis (PCM) is the most prevalent systemic mycosis in Latin American countries. Amphotericin B, sulfonamides, and azoles may be used in the treatment of PCM. However, the high toxicity, prolonged course of treatment, and significant frequency of disease relapse compromise their use. Therefore, there is a need to seek new therapeutic options. We conducted tests with thiosemicarbazone of lapachol (TSC-lap) to determine the antifungal activity and phenotypic effects against several isolates of Paracoccidioides spp. In addition, we evaluated the toxicity against murine macrophages and the ability to enhance phagocytosis. Further, we verified that TSC-lap was active against yeasts but did not show any interaction with the drugs tested. The TSC-lap showed no toxicity at the concentration of 40 μg/ml in macrophages, and at 15.6 μg/ml it could increase the phagocytic index. We observed that this compound induced in vitro ultrastructural changes manifested as withered and broken cells beyond a disorganized cytoplasm with accumulation of granules. We did not observe indications of activity in the cell wall, although membrane damages were noted. We observed alterations in the membrane permeability, culminating in a significant increase in K+ efflux and a gradual loss of the cellular content with increase in the concentration of TSC-lap. In addition, we showed a significant reduction of ergosterol amount in the Pb18 membrane. These data reinforce the possible mechanism of action of this compound to be closely associated with ergosterol biosynthesis and reaffirms the antifungal potential of TSC-lap against Paracoccidioides spp.
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Affiliation(s)
- Nívea Pereira de Sá
- Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Patrícia Silva Cisalpino
- Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Caryne Margotto Bertollo
- Laboratory of Chemistry of Natural Products, René Rachou Research Center, FIOCRUZ, Belo Horizonte, MG, Brazil
| | - Patrícia Campi Santos
- Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Carlos Augusto Rosa
- Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Daniele da Glória de Souza
- Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Paulo Jorge Sanches Barbeira
- Departamento de Química, Instituto de Ciências Exatas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | | | - Carlos Leomar Zani
- Laboratory of Chemistry of Natural Products, René Rachou Research Center, FIOCRUZ, Belo Horizonte, MG, Brazil
| | - Susana Johann
- Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
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12
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Marreiro de Sales-Neto J, Lima ÉA, Cavalcante-Silva LHA, Vasconcelos U, Rodrigues-Mascarenhas S. Anti-inflammatory potential of pyocyanin in LPS-stimulated murine macrophages. Immunopharmacol Immunotoxicol 2019; 41:102-108. [PMID: 30623710 DOI: 10.1080/08923973.2018.1555845] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Context: Pyocyanin is a typical Pseudomonas aeruginosa virulence factor, a common Gram-negative rod responsible for a wide range of severe nosocomial infections. There is evidence indicating that pyocyanin has multiple biological activities, but little is known about anti-inflammatory properties. Objective: This study investigated pyocyanin effect on nitric oxide and cytokine production in lipopolysaccharide (LPS)-activated murine peritoneal macrophages. Materials and methods: Macrophages were incubated in the presence and absence of pyocyanin (1, 5, 10, 50, and 100 µM) with and without LPS (1 µg/mL). Nitric oxide production was determined by Griess reagent and tumor necrosis factor (TNF)-α and interleukin (IL)-1β production was assessed by enzyme-linked immunosorbent assay. In addition, pyocyanin effects on zymosan A-induced peritonitis in mice were evaluated. Results: Pyocyanin (5 and 10 µM) decreased nitric oxide, TNF-α, and IL-1β production independent of macrophage death. On the other hand, in vivo, pyocyanin (5 mg/kg) was not able to affect leukocyte migration into the site of inflammation. Discussion and conclusion: Thus, our findings suggest that pyocyanin exerts anti-inflammatory effects on murine peritoneal macrophages, downregulating nitric oxide, TNF-α, and IL-1β levels, which seems to be independent of cell migration. These effects may represent a mechanism of immune evasion; nevertheless more detailed studies should be performed to confirm this hypothesis.
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Affiliation(s)
| | - É A Lima
- a Departamento de Biologia Celular e Molecular , Universidade Federal da Paraíba , João Pessoa , Brazil
| | - L H A Cavalcante-Silva
- a Departamento de Biologia Celular e Molecular , Universidade Federal da Paraíba , João Pessoa , Brazil
| | - U Vasconcelos
- b Departamento de Biotecnologia , Universidade Federal da Paraíba , João Pessoa , Brazil
| | - S Rodrigues-Mascarenhas
- a Departamento de Biologia Celular e Molecular , Universidade Federal da Paraíba , João Pessoa , Brazil
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Tristão FSM, Rocha FA, Carlos D, Ketelut-Carneiro N, Souza COS, Milanezi CM, Silva JS. Th17-Inducing Cytokines IL-6 and IL-23 Are Crucial for Granuloma Formation during Experimental Paracoccidioidomycosis. Front Immunol 2017; 8:949. [PMID: 28871251 PMCID: PMC5566564 DOI: 10.3389/fimmu.2017.00949] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Accepted: 07/25/2017] [Indexed: 01/06/2023] Open
Abstract
Paracoccidioidomycosis (PCM), a chronic granulomatous disease caused by the thermally dimorphic fungus Paracoccidioides brasiliensis and Paracoccidioides lutzii, has the highest mortality rate among systemic mycosis. The T helper 1-mediated immunity is primarily responsible for acquired resistance during P. brasiliensis infection, while susceptibility is associated with Th2 occurrence. Th17 is a population of T CD4+ cells that, among several chemokines and cytokines, produces IL-17A and requires the presence of IL-1, IL-6, and TGF-β for differentiation in mice and IL-23 for its maintenance. Th17 has been described as an arm of the immune system that enhances host protection against several bacterial and fungal infections, as Pneumocystis carinii and Candida albicans. In this study, we aimed to evaluate the Th17 immune response and the role of Th17-associated cytokines (IL-6, IL-23, and IL-17A) during experimental PCM. First, we observed that P. brasiliensis infection [virulent yeast strain 18 of P. brasiliensis (Pb18)] increased the IL-17A production in vitro and all the evaluated Th17-associated cytokines in the lung tissue from C57BL/6 wild-type mice. In addition, the deficiency of IL-6, IL-23, or IL-17 receptor A (IL-17RA) impaired the compact granuloma formation and conferred susceptibility during infection, associated with reduced tumor necrosis factor-α, IFN-γ, and inducible nitric oxide synthase enzyme expression. Our data suggest that IL-6 production by bone marrow-derived macrophages (BMDMs) is important to promote the Th17 differentiation during Pb18 infection. In accordance, the adoptive transfer of BMDMs from C57BL/6 to infected IL-6-/- or IL-17RA-/- mice reduced the fungal burden in the lungs compared to nontransferred mice and reestablished the pulmonary granuloma formation. Taken together, these results suggest that Th17-associated cytokines are involved in the modulation of immune response and granuloma formation during experimental PCM.
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Affiliation(s)
- Fabrine Sales Massafera Tristão
- Department of Biochemistry and Immunology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil
| | - Fernanda Agostini Rocha
- Department of Biochemistry and Immunology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil
| | - Daniela Carlos
- Department of Biochemistry and Immunology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil
| | - Natália Ketelut-Carneiro
- Department of Biochemistry and Immunology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil
| | - Camila Oliveira Silva Souza
- Department of Biochemistry and Immunology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil
| | - Cristiane Maria Milanezi
- Department of Biochemistry and Immunology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil
| | - João Santana Silva
- Department of Biochemistry and Immunology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil
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de Araújo EF, Feriotti C, Galdino NADL, Preite NW, Calich VLG, Loures FV. The IDO-AhR Axis Controls Th17/Treg Immunity in a Pulmonary Model of Fungal Infection. Front Immunol 2017; 8:880. [PMID: 28791025 PMCID: PMC5523665 DOI: 10.3389/fimmu.2017.00880] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Accepted: 07/10/2017] [Indexed: 12/20/2022] Open
Abstract
In infectious diseases, the enzyme indoleamine 2,3 dioxygenase-1 (IDO1) that catalyzes the tryptophan (Trp) degradation along the kynurenines (Kyn) pathway has two main functions, the control of pathogen growth by reducing available Trp and immune regulation mediated by the Kyn-mediated expansion of regulatory T (Treg) cells via aryl hydrocarbon receptor (AhR). In pulmonary paracoccidioidomycosis (PCM) caused by the dimorphic fungus Paracoccidioides brasiliensis, IDO1 was shown to control the disease severity of both resistant and susceptible mice to the infection; however, only in resistant mice, IDO1 is induced by TGF-β signaling that confers a stable tolerogenic phenotype to dendritic cells (DCs). In addition, in pulmonary PCM, the tolerogenic function of plasmacytoid dendritic cells was linked to the IDO1 activity. To further evaluate the function of IDO1 in pulmonary PCM, IDO1-deficient (IDO1-/-) C57BL/6 mice were intratracheally infected with P. brasiliensis yeasts and the infection analyzed at three postinfection periods regarding several parameters of disease severity and immune response. The fungal loads and tissue pathology of IDO1-/- mice were higher than their wild-type controls resulting in increased mortality rates. The evaluation of innate lymphoid cells showed an upregulated differentiation of the innate lymphoid cell 3 phenotype accompanied by a decreased expansion of ILC1 and NK cells in the lungs of infected IDO1-/- mice. DCs from these mice expressed elevated levels of costimulatory molecules and cytokine IL-6 associated with reduced production of IL-12, TNF-α, IL-1β, TGF-β, and IL-10. This response was concomitant with a marked reduction in AhR production. The absence of IDO1 expression caused an increased influx of activated Th17 cells to the lungs with a simultaneous reduction in Th1 and Treg cells. Accordingly, the suppressive cytokines IL-10, TGF-β, IL-27, and IL-35 appeared in reduced levels in the lungs of IDO1-/- mice. In conclusion, the immunological balance mediated by the axis IDO/AhR is fundamental to determine the balance between Th17/Treg cells and control the severity of pulmonary PCM.
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Affiliation(s)
- Eliseu Frank de Araújo
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil
| | - Claudia Feriotti
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil
| | | | - Nycolas Willian Preite
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil
| | - Vera Lúcia Garcia Calich
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil
| | - Flávio Vieira Loures
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil
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15
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de Araújo EF, Medeiros DH, Galdino NADL, Condino-Neto A, Calich VLG, Loures FV. Tolerogenic Plasmacytoid Dendritic Cells Control Paracoccidioides brasiliensis Infection by Inducting Regulatory T Cells in an IDO-Dependent Manner. PLoS Pathog 2016; 12:e1006115. [PMID: 27992577 PMCID: PMC5215616 DOI: 10.1371/journal.ppat.1006115] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 01/04/2017] [Accepted: 12/09/2016] [Indexed: 11/26/2022] Open
Abstract
Plasmacytoid dendritic cells (pDCs), considered critical for immunity against viruses, were recently associated with defense mechanisms against fungal infections. However, the immunomodulatory function of pDCs in pulmonary paracoccidiodomycosis (PCM), an endemic fungal infection of Latin America, has been poorly defined. Here, we investigated the role of pDCs in the pathogenesis of PCM caused by the infection of 129Sv mice with 1 x 106P. brasiliensis-yeasts. In vitro experiments showed that P. brasiliensis infection induces the maturation of pDCs and elevated synthesis of TNF-α and IFN-β. The in vivo infection caused a significant influx of pDCs to the lungs and increased levels of pulmonary type I IFN. Depletion of pDCs by a specific monoclonal antibody resulted in a less severe infection, reduced tissue pathology and increased survival time of infected mice. An increased influx of macrophages and neutrophils and elevated presence of CD4+ and CD8+ T lymphocytes expressing IFN-γ and IL-17 in the lungs of pDC-depleted mice were also observed. These findings were concomitant with decreased frequency of Treg cells and reduced levels of immunoregulatory cytokines such as IL-10, TGF-β, IL-27 and IL-35. Importantly, P. brasilienis infection increased the numbers of pulmonary pDCs expressing indoleamine 2,3-dioxygenase-1 (IDO), an enzyme with immunoregulatory properties, that were reduced following pDC depletion. In agreement, an increased immunogenic activity of infected pDCs was observed when IDO-deficient or IDO-inhibited pDCs were employed in co-cultures with lymphocytes Altogether, our results suggest that in pulmonary PCM pDCs exert a tolerogenic function by an IDO-mediated mechanism that increases Treg activity. The fungus Paracoccidioides brasiliensis causes paracoccidioidomycosis (PCM), the most relevant deep mycosis in Latin America. The plasmacytoid dendritic cells (pDCs) are important immune cells involved in protection against viral infections, but their role in fungal infections remains unclear. Here, we investigated the role of pDCs in the pathogenesis of pulmonary PCM using a monoclonal antibody to deplete this DC subset. pDCs depletion leads to a less severe PCM associated with increased T cell response mainly mediated by Th1 and Th17 cells. The lung homogenates of depleted mice showed diminished levels of type I IFN and anti-inflammatory cytokines. In addition, a reduced number of regulatory T cells (Treg) paralleled a diminished number pDCs expressing IDO, a potent immunoregulatory enzyme. In agreement, pDCs of IDO-/- mice or IDO-inhibited pDCs stimulated by P. brasiliensis yeasts expanded elevated numbers of T cells concomitant with a reduced expansion of Treg cells. Taken together, our results demonstrate a tolerogenic activity of pDCs that enhances the severity of a pulmonary mycosis mediated by the concerted action of IDO and Treg cells. These results reveal a new function for pDCs in primary fungal infections and open new perspectives for immunotherapeutic procedures of PCM involving the control of IDO and Treg activity.
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Affiliation(s)
- Eliseu Frank de Araújo
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Daniella Helena Medeiros
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brazil
| | | | - Antônio Condino-Neto
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Vera Lúcia Garcia Calich
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Flávio Vieira Loures
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brazil
- * E-mail:
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16
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Lipoxin Inhibits Fungal Uptake by Macrophages and Reduces the Severity of Acute Pulmonary Infection Caused by Paracoccidioides brasiliensis. Mediators Inflamm 2015; 2015:852574. [PMID: 26635449 PMCID: PMC4618125 DOI: 10.1155/2015/852574] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Accepted: 09/20/2015] [Indexed: 01/01/2023] Open
Abstract
Cysteinyl leukotrienes (CysLTs) and lipoxins (LXs) are lipid mediators that control inflammation, with the former inducing and the latter inhibiting this process. Because the role played by these mediators in paracoccidioidomycosis was not investigated, we aimed to characterize the role of CysLT in the pulmonary infection developed by resistant (A/J) and susceptible (B10.A) mice. 48 h after infection, elevated levels of pulmonary LTC4 and LXA4 were produced by both mouse strains, but higher levels were found in the lungs of susceptible mice. Blocking the CysLTs receptor by MTL reduced fungal loads in B10.A, but not in A/J mice. In susceptible mice, MLT treatment led to reduced influx of PMN leukocytes, increased recruitment of monocytes, predominant synthesis of anti-inflammatory cytokines, and augmented expression of 5- and 15-lipoxygenase mRNA, suggesting a prevalent LXA4 activity. In agreement, MTL-treated macrophages showed reduced fungal burdens associated with decreased ingestion of fungal cells. Furthermore, the addition of exogenous LX reduced, and the specific blockade of the LX receptor increased the fungal loads of B10.A macrophages. This study showed for the first time that inhibition of CysLTs signaling results in less severe pulmonary paracoccidioidomycosis that occurs in parallel with elevated LX activity and reduced infection of macrophages.
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Cardillo F, de Pinho RT, Antas PRZ, Mengel J. Immunity and immune modulation in Trypanosoma cruzi infection. Pathog Dis 2015; 73:ftv082. [PMID: 26438729 DOI: 10.1093/femspd/ftv082] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/30/2015] [Indexed: 12/28/2022] Open
Abstract
Chagas disease is caused by the protozoan Trypanosoma cruzi. The parasite reaches the secondary lymphoid organs, the heart, skeletal muscles, neurons in the intestine and esophagus among other tissues. The disease is characterized by mega syndromes, which may affect the esophagus, the colon and the heart, in about 30% of infected people. The clinical manifestations associated with T. cruzi infection during the chronic phase of the disease are dependent on complex interactions between the parasite and the host tissues, particularly the lymphoid system that may either result in a balanced relationship with no disease or in an unbalanced relationship that follows an inflammatory response to parasite antigens and associated tissues in some of the host organs and/or by an autoimmune response to host antigens. This review discusses the findings that support the notion of an integrated immune response, considering the innate and adaptive arms of the immune system in the control of parasite numbers and also the mechanisms proposed to regulate the immune response in order to tolerate the remaining parasite load, during the chronic phase of infection. This knowledge is fundamental to the understanding of the disease progression and is essential for the development of novel therapies and vaccine strategies.
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Affiliation(s)
- Fabíola Cardillo
- Oswaldo Cruz Foundation, Bahia, Rua Waldemar Falcão 121, Salvador 40295-001, Brazil
| | - Rosa Teixeira de Pinho
- Laboratório de Imunologia Clínica, Instituto Oswaldo Cruz, Oswaldo Cruz Foundation, Rio de Janeiro 21040-900, Brazil
| | - Paulo Renato Zuquim Antas
- Laboratório de Imunologia Clínica, Instituto Oswaldo Cruz, Oswaldo Cruz Foundation, Rio de Janeiro 21040-900, Brazil
| | - José Mengel
- Laboratório de Imunologia Clínica, Instituto Oswaldo Cruz, Oswaldo Cruz Foundation, Rio de Janeiro 21040-900, Brazil Faculty of Medicine of Petropolis, FMP-FASE, 25680-120, Petrópolis, Rio de Janeiro, Brazil
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18
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da Costa TA, Di Gangi R, Martins P, Longhini ALF, Zanucoli F, de Oliveira ALR, Stach-Machado DR, Burger E, Verinaud L, Thomé R. Protection against Paracoccidioides brasiliensis infection in mice treated with modulated dendritic cells relies on inhibition of interleukin-10 production by CD8+ T cells. Immunology 2015; 146:486-95. [PMID: 26302057 DOI: 10.1111/imm.12526] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Revised: 08/08/2015] [Accepted: 08/18/2015] [Indexed: 11/27/2022] Open
Abstract
Paracoccidioidomycosis is a systemic infection prevalent in Latin American countries. Disease develops after inhalation of Paracoccidioides brasiliensis conidia followed by an improper immune activation by the host leucocytes. Dendritic cells (DCs) are antigen-presenting cells with the unique ability to direct the adaptive immune response by the time of activation of naive T cells. This study was conducted to test whether extracts of P. brasiliensis would induce maturation of DCs. We found that DCs treated with extracts acquired an inflammatory phenotype and upon adoptive transfer conferred protection to infection. Interestingly, interleukin-10 production by CD8(+) T cells was ablated following DC transfer. Further analyses showed that lymphocytes from infected mice were high producers of interleukin-10, with CD8(+) T cells being the main source. Blockage of cross-presentation to CD8(+) T cells by modulated DCs abolished the protective effect of adoptive transfer. Collectively, our data show that adoptive transfer of P. brasiliensis-modulated DCs is an interesting approach for the control of infection in paracoccidioidomycosis.
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Affiliation(s)
- Thiago Alves da Costa
- Department of Structural and Functional Biology, Institute of Biology, University of Campinas, Campinas, SP, Brazil
| | - Rosária Di Gangi
- Department of Structural and Functional Biology, Institute of Biology, University of Campinas, Campinas, SP, Brazil
| | - Paula Martins
- Department of Structural and Functional Biology, Institute of Biology, University of Campinas, Campinas, SP, Brazil
| | | | - Fábio Zanucoli
- Department of Structural and Functional Biology, Institute of Biology, University of Campinas, Campinas, SP, Brazil
| | | | - Dagmar Ruth Stach-Machado
- Department of Structural and Functional Biology, Institute of Biology, University of Campinas, Campinas, SP, Brazil
| | - Eva Burger
- Instituto de Biociências, Universidade Federal de Alfenas, Alfenas, MG, Brazil
| | - Liana Verinaud
- Department of Structural and Functional Biology, Institute of Biology, University of Campinas, Campinas, SP, Brazil
| | - Rodolfo Thomé
- Department of Structural and Functional Biology, Institute of Biology, University of Campinas, Campinas, SP, Brazil
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19
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Feriotti C, Bazan SB, Loures FV, Araújo EF, Costa TA, Calich VLG. Expression of dectin-1 and enhanced activation of NALP3 inflammasome are associated with resistance to paracoccidioidomycosis. Front Microbiol 2015; 6:913. [PMID: 26388856 PMCID: PMC4558525 DOI: 10.3389/fmicb.2015.00913] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Accepted: 08/20/2015] [Indexed: 02/02/2023] Open
Abstract
Dectin-1 is a pattern recognition receptor (PRR) that recognizes β-glucans and plays a major role in the immunity against fungal pathogens. Paracoccidioides brasiliensis, the causative agent of paracoccidioidomycosis, has a sugar-rich cell wall mainly composed of mannans and glucans. To investigate the role of dectin-1 in the innate immunity of resistant (A/J) and susceptible (B10.A) mice to P. brasiliensis infection, we evaluated the role of curdlan (a dectin-1 agonist) and laminarin (a dectin-1 antagonist) in the activation of macrophages from both mouse strains. We verified that curdlan has a negligible role in the activation of B10.A macrophages but enhances the phagocytic and fungicidal abilities of A/J macrophages. Curdlan up-regulated the expression of costimulatory molecules and PRRs in A/J macrophages that express elevated levels of dectin-1, but not in B10.A cells. In addition, curdlan treatment inhibited arginase-1 and enhanced NO-synthase mRNA expression in infected A/J macrophages but had not effect in B10.A cells. In contrast, laminarin reinforced the respective M2/M1 profiles of infected A/J and B10.A macrophages. Following curdlan treatment, A/J macrophages showed significantly higher Syk kinase phosphorylation and expression of intracellular pro-IL-1β than B10.A cells. These findings led us to investigate if the NRLP3 inflammasome was differently activated in A/J and B10.A cells. Indeed, compared with B10.A cells A/J macrophages showed an increased expression of NALP3, ASC, and IL-1β mRNA. They also showed elevated caspase-1 activity and secreted high levels of mature IL-β and IL-18 after curdlan treatment and P. brasiliensis infection. Our data demonstrate that soluble and particulate β-glucans exert opposed modulatory activities on macrophages of diverse genetic patterns. Moreover, the synergistic action of dectin-1 and NALP3 inflammasome were for the first time associated with the innate response of resistant hosts to P. brasiliensis infection.
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Affiliation(s)
- Claudia Feriotti
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo São Paulo, Brazil
| | - Silvia B Bazan
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo São Paulo, Brazil
| | - Flávio V Loures
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo São Paulo, Brazil
| | - Eliseu F Araújo
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo São Paulo, Brazil
| | - Tânia A Costa
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo São Paulo, Brazil
| | - Vera L G Calich
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo São Paulo, Brazil
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20
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Tavares AH, Fernandes L, Bocca AL, Silva-Pereira I, Felipe MS. Transcriptomic reprogramming of genus Paracoccidioides in dimorphism and host niches. Fungal Genet Biol 2015; 81:98-109. [DOI: 10.1016/j.fgb.2014.01.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2013] [Revised: 01/27/2014] [Accepted: 01/31/2014] [Indexed: 01/04/2023]
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Araújo EF, Loures FV, Bazan SB, Feriotti C, Pina A, Schanoski AS, Costa TA, Calich VLG. Indoleamine 2,3-dioxygenase controls fungal loads and immunity in Paracoccidioidomicosis but is more important to susceptible than resistant hosts. PLoS Negl Trop Dis 2014; 8:e3330. [PMID: 25411790 PMCID: PMC4238999 DOI: 10.1371/journal.pntd.0003330] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Accepted: 10/08/2014] [Indexed: 11/29/2022] Open
Abstract
Background Paracoccidioidomycosis, a primary fungal infection restricted to Latin America, is acquired by inhalation of fungal particles. The immunoregulatory mechanisms that control the severe and mild forms of paracoccidioidomycosis are still unclear. Indoleamine 2,3-dioxygenase (IDO), an IFN-γ induced enzyme that catalyzes tryptophan metabolism, can control host-pathogen interaction by inhibiting pathogen growth, T cell immunity and tissue inflammation. Methodology/Principal Findings In this study, we investigated the role of IDO in pulmonary paracoccidioidomycosis of susceptible and resistant mice. IDO was blocked by 1-methyl-dl-tryptophan (1MT), and fungal infection studied in vitro and in vivo. Paracoccidioides brasiliensis infection was more severe in 1MT treated than untreated macrophages of resistant and susceptible mice, concurrently with decreased production of kynurenines and IDO mRNA. Similar results were observed in the pulmonary infection. Independent of the host genetic pattern, IDO inhibition reduced fungal clearance but enhanced T cell immunity. The early IDO inhibition resulted in increased differentiation of dendritic and Th17 cells, accompanied by reduced responses of Th1 and Treg cells. Despite these equivalent biological effects, only in susceptible mice the temporary IDO blockade caused sustained fungal growth, increased tissue pathology and mortality rates. In contrast, resistant mice were able to recover the transitory IDO blockade by the late control of fungal burdens without enhanced tissue pathology. Conclusions/Significance Our studies demonstrate for the first time that in pulmonary paracoccidioidomycosis, IDO is an important immunoregulatory enzyme that promotes fungal clearance and inhibits T cell immunity and inflammation, with prominent importance to susceptible hosts. In fact, only in the susceptible background IDO inhibition resulted in uncontrolled tissue pathology and mortality rates. Our findings open new perspectives to understand the immunopathology of paracoccidioidomycosis, and suggest that an insufficient IDO activity could be associated with the severe cases of human PCM characterized by inefficient fungal clearance and excessive inflammation. Immunoprotection to paracoccidiodomycosis, a systemic mycosis endemic in Latin America, is mediated by T cell immunity whereas immunosuppression characterizes the severe forms of the disease. Indoleamine 2,3-dioxygenase (IDO), an enzyme mainly induced by IFN-γ, catabolizes tryptophan along the kynurenines pathway. Tryptophan deficiency has been associated with reduced pathogen growth, while elevated levels of kynurenines with suppressed immune responses. In this study, the role of IDO in pulmonary paracoccidioidomycosis was investigated using resistant and susceptible mice. In both mouse strains, IDO blockade by 1-methyl tryptophan resulted in inefficient fungal clearance accompanied by enhanced T cell immunity. Despite these equivalent biological effects, only in susceptible mice IDO inhibition caused progressive fungal growth and tissue pathology resulting in increased mortality. Our findings demonstrate for the first time that IDO exert a yet unexplored immunoregulatory role in pulmonary paracoccidioidomycosis that can be particularly important in the severe cases of the disease.
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Affiliation(s)
- Eliseu F. Araújo
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, São Paulo, Brazil
| | - Flávio V. Loures
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, São Paulo, Brazil
| | - Silvia B. Bazan
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, São Paulo, Brazil
| | - Claudia Feriotti
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, São Paulo, Brazil
| | - Adriana Pina
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, São Paulo, Brazil
| | - Alessandra S. Schanoski
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, São Paulo, Brazil
| | - Tânia A. Costa
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, São Paulo, Brazil
| | - Vera L. G. Calich
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, São Paulo, Brazil
- * E-mail:
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Role of omega-3 polyunsaturated fatty acids in the production of prostaglandin E2 and nitric oxide during experimental murine paracoccidioidomycosis. BIOMED RESEARCH INTERNATIONAL 2013; 2013:947687. [PMID: 24455741 PMCID: PMC3886617 DOI: 10.1155/2013/947687] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/18/2013] [Revised: 09/25/2013] [Accepted: 10/07/2013] [Indexed: 11/23/2022]
Abstract
There has recently been increased interest in the potential health effects of omega-3 polyunsaturated fatty acids on the immune system. Paracoccidioidomycosis is the most important endemic mycosis in Latin America. Macrophages have a fundamental role and act as first line of organism defense. The purpose of this study was to analyze the effect of n-3 fatty acids on the production of PGE2 and NO by mice infected with Pb18 and fed a diet enriched with LNA for 8 weeks. To study the effect of omega-3 fatty acids on macrophage activity during experimental paracoccidioidomycosis, mice were infected with Pb18 and fed a diet supplemented with LNA. PGE2 in the serum of animals was analyzed and NO in the supernatants of macrophages cultured and challenged in vitro with Pb18 was measured. Omega-3 fatty acids seemed to decrease the production of PGE2 in vivo in the infected group fed an LNA-supplemented diet during the 4th and 8th weeks of the experiment. At the same time, we observed an increase in synthesis of NO by peritoneal macrophages in this group. Omega-3 fatty acids thus appear to have an immunomodulatory effect in paracoccidioidomycosis.
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Tavares AH, Magalhães KG, Almeida RDN, Correa R, Burgel PH, Bocca AL. NLRP3 inflammasome activation by Paracoccidioides brasiliensis. PLoS Negl Trop Dis 2013; 7:e2595. [PMID: 24340123 PMCID: PMC3855149 DOI: 10.1371/journal.pntd.0002595] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2013] [Accepted: 10/31/2013] [Indexed: 12/11/2022] Open
Abstract
Paracoccidioides brasiliensis is the etiologic agent of paracoccidioidomycosis (PCM), the most prevalent systemic mycosis that is geographically confined to Latin America. The pro-inflammatory cytokine IL-1β that is mainly derived from the activation of the cytoplasmic multiprotein complex inflammasome is an essential host factor against opportunistic fungal infections; however, its role in infection with a primary fungal pathogen, such as P. brasiliensis, is not well understood. In this study, we found that murine bone marrow-derived dendritic cells responded to P. brasiliensis yeast cells infection by releasing IL-1β in a spleen tyrosine kinase (Syk), caspase-1 and NOD-like receptor (NLR) family member NLRP3 dependent manner. In addition, P. brasiliensis-induced NLRP3 inflammasome activation was dependent on potassium (K+) efflux, reactive oxygen species production, phagolysosomal acidification and cathepsin B release. Finally, using mice lacking the IL-1 receptor, we demonstrated that IL-1β signaling has an important role in killing P. brasiliensis by murine macrophages. Altogether, our results demonstrate that the NLRP3 inflammasome senses and responds to P. brasiliensis yeast cells infection and plays an important role in host defense against this fungus. Paracoccidioidomycosis is a systemic disease that has an important mortality and morbidity impact in Latin America. It mainly affects rural workers of Argentina, Colombia, Venezuela and Brazil. Upon host infection, one of the most important aspects that contribute to the disease outcome is the initial interaction of the Paracoccidioides brasiliensis fungus with the phagocytic cells and the induction of the inflammatory process. Among several inflammatory mediators, the cytokine interleukin-1β is of pivotal importance in this complex process. Here, we demonstrate that P. brasiliensis is sensed by the NLRP3 inflammasome, a cytoplasmatic multiprotein complex that lead to the processing and secretion of IL-1β. In addition, we described the intracellular perturbations that may be associated with NLRP3 activation such as potassium efflux, production of reactive oxygen species, and lysosomal damage. Finally, our work provides evidence for the protective role of IL-1β during fungal infection of murine macrophages.
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Affiliation(s)
- Aldo Henrique Tavares
- Faculdade de Ceilândia, Universidade de Brasília, Brasília, Distrito Federal, Brasil
- Laboratorio de Imunologia Aplicada, Departamento de Biologia Celular, Instituto de Biologia, Universidade de Brasília, Brasília, Distrito Federal, Brasil
- * E-mail: .
| | - Kelly Grace Magalhães
- Laboratorio de Imunologia e Inflamação, Departamento de Biologia Celular, Instituto de Biologia, Universidade de Brasília, Brasília, Distrito Federal, Brasil
| | - Raquel Das Neves Almeida
- Laboratorio de Imunologia e Inflamação, Departamento de Biologia Celular, Instituto de Biologia, Universidade de Brasília, Brasília, Distrito Federal, Brasil
| | - Rafael Correa
- Laboratorio de Imunologia e Inflamação, Departamento de Biologia Celular, Instituto de Biologia, Universidade de Brasília, Brasília, Distrito Federal, Brasil
| | - Pedro Henrique Burgel
- Laboratorio de Imunologia Aplicada, Departamento de Biologia Celular, Instituto de Biologia, Universidade de Brasília, Brasília, Distrito Federal, Brasil
| | - Anamélia Lorenzetti Bocca
- Laboratorio de Imunologia Aplicada, Departamento de Biologia Celular, Instituto de Biologia, Universidade de Brasília, Brasília, Distrito Federal, Brasil
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Tristão FSM, Rocha FA, Dias FC, Rossi MA, Silva JS. The left lung is preferentially targeted during experimental paracoccidioidomycosis in C57BL/6 mice. Braz J Med Biol Res 2013; 46:839-43. [PMID: 24141611 PMCID: PMC3854305 DOI: 10.1590/1414-431x20133140] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Accepted: 07/29/2013] [Indexed: 11/21/2022] Open
Abstract
Paracoccidioidomycosis (PCM) is a chronic systemic mycosis caused by the
inhalation of the thermally dimorphic fungus Paracoccidioides
brasiliensis as well as the recently described P.
lutzii. Because the primary infection occurs in the lungs, we
investigated the differential involvement of the right and left lungs in
experimental P. brasiliensis infection. Lungs were collected
from C57BL/6 mice at 70 days after intravenous infection with 1×106
yeast cells of a virulent strain of P. brasiliensis (Pb18). The
left lung, which in mice is smaller and has fewer lobes than the right lung,
yielded increased fungal recovery associated with a predominant interleukin-4
response and diminished synthesis of interferon-γ and nitric oxide compared with
the right lung. Our data indicate differential involvement of the right and left
lungs during experimental PCM. This knowledge emphasizes the need for an
accurate, standardized protocol for tissue collection during studies of
experimental P. brasiliensis infection, since experiments using
the same lungs favor the collection of comparable data among different mice.
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Affiliation(s)
- F S M Tristão
- Departamento de Bioquímica e Imunologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão PretoSP, Brasil
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Bernardino S, Pina A, Felonato M, Costa TA, Frank de Araújo E, Feriotti C, Bazan SB, Keller AC, Leite KRM, Calich VLG. TNF-α and CD8+ T cells mediate the beneficial effects of nitric oxide synthase-2 deficiency in pulmonary paracoccidioidomycosis. PLoS Negl Trop Dis 2013; 7:e2325. [PMID: 23936574 PMCID: PMC3731220 DOI: 10.1371/journal.pntd.0002325] [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: 08/27/2012] [Accepted: 06/09/2013] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND Nitric oxide (NO), a key antimicrobial molecule, was previously shown to exert a dual role in paracoccidioidomycosis, an endemic fungal infection in Latin America. In the intravenous and peritoneal models of infection, NO production was associated with efficient fungal clearance but also with non-organized granulomatous lesions. Because paracoccidioidomycosis is a pulmonary infection, we aimed to characterize the role of NO in a pulmonary model of infection. METHODOLOGY/PRINCIPAL FINDINGS C57Bl/6 wild type (WT) and iNOS(-/-) mice were i.t. infected with 1×10(6) Paracoccidioides brasiliensis yeasts and studied at several post-infection periods. Unexpectedly, at week 2 of infection, iNOS(-/-) mice showed decreased pulmonary fungal burdens associated with an M2-like macrophage profile, which expressed high levels of TGF-β impaired ability of ingesting fungal cells. This early decreased fungal loads were concomitant with increased DTH reactions, enhanced TNF-α synthesis and intense migration of activated macrophages, CD4(+) and CD8(+) T cells into the lungs. By week 10, iNOS(-/-) mice showed increased fungal burdens circumscribed, however, by compact granulomas containing elevated numbers of activated CD4(+) T cells. Importantly, the enhanced immunological reactivity of iNOS(-/-) mice resulted in decreased mortality rates. In both mouse strains, depletion of TNF-α led to non-organized lesions and excessive influx of inflammatory cells into the lungs, but only the iNOS(-/-) mice showed increased mortality rates. In addition, depletion of CD8(+) cells abolished the increased migration of inflammatory cells and decreased the number of TNF-α and IFN-γ CD4(+) and CD8(+) T cells into the lungs of iNOS(-/-) mice. CONCLUSIONS/SIGNIFICANCE Our study demonstrated that NO plays a deleterious role in pulmonary paracoccidioidomycosis due to its suppressive action on TNF-α production, T cell immunity and organization of lesions resulting in precocious mortality of mice. It was also revealed that uncontrolled fungal growth can be overcome by an efficient immune response.
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Affiliation(s)
- Simone Bernardino
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brasil
| | - Adriana Pina
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brasil
| | - Maíra Felonato
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brasil
| | - Tânia A. Costa
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brasil
| | - Eliseu Frank de Araújo
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brasil
| | - Cláudia Feriotti
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brasil
| | - Silvia Boschi Bazan
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brasil
| | - Alexandre C. Keller
- Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo, São Paulo, Brasil
| | - Katia R. M. Leite
- Departamento de Patologia, Hospital Sírio Libanês de São Paulo, São Paulo, Brasil
| | - Vera L. G. Calich
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brasil
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Low concentrations of hydrogen peroxide or nitrite induced of Paracoccidioides brasiliensis cell proliferation in a Ras-dependent manner. PLoS One 2013; 8:e69590. [PMID: 23922749 PMCID: PMC3726682 DOI: 10.1371/journal.pone.0069590] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2013] [Accepted: 06/10/2013] [Indexed: 01/27/2023] Open
Abstract
Paracoccidioides brasiliensis, a causative agent of paracoccidioidomycosis (PCM), should be able to adapt to dramatic environmental changes inside the infected host after inhalation of air-borne conidia and transition to pathogenic yeasts. Proteins with antioxidant functions may protect fungal cells against reactive oxygen (ROS) and nitrogen (RNS) species generated by phagocytic cells, thus acting as potential virulence factors. Ras GTPases are involved in stress responses, cell morphology, and differentiation in a range of organisms. Ras, in its activated form, interacts with effector proteins and can initiate a kinase cascade. In lower eukaryotes, Byr2 kinase represents a Ras target. The present study investigated the role of Ras in P. brasiliensis after in vitro stimulus with ROS or RNS. We have demonstrated that low concentrations of H2O2 (0.1 mM) or NO2 (0.1–0.25 µM) stimulated P. brasiliensis yeast cell proliferation and that was not observed when yeast cells were pre-incubated with farnesyltransferase inhibitor. We constructed an expression plasmid containing the Byr2 Ras-binding domain (RBD) fused with GST (RBD-Byr2-GST) to detect the Ras active form. After stimulation with low concentrations of H2O2 or NO2, the Ras active form was observed in fungal extracts. Besides, NO2 induced a rapid increase in S-nitrosylated Ras levels. This alternative posttranslational modification of Ras, probably in residue Cys123, would lead to an exchange of GDP for GTP and consequent GTPase activation in P. brasiliensis. In conclusion, low concentrations of H2O2 or NO2 stimulated P. brasiliensis proliferation through Ras activation.
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27
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Alegranci P, de Abreu Ribeiro LC, Ferreira LS, Negrini TDC, Maia DCG, Tansini A, Gonçalves AC, Placeres MCP, Carlos IZ. The predominance of alternatively activated macrophages following challenge with cell wall peptide-polysaccharide after prior infection with Sporothrix schenckii. Mycopathologia 2013; 176:57-65. [PMID: 23686275 DOI: 10.1007/s11046-013-9663-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2013] [Accepted: 05/02/2013] [Indexed: 10/26/2022]
Abstract
Sporotrichosis is a subcutaneous mycosis that is caused by the dimorphic fungus Sporothrix schenckii. This disease generally occurs within the skin and subcutaneous tissues, causing lesions that can spread through adjacent lymphatic vessels and sometimes leading to systemic diseases in immunocompromised patients. Macrophages are crucial for proper immune responses against a variety of pathogens. Furthermore, macrophages can play different roles in response to different microorganisms and forms of activation, and they can be divided into "classic" or "alternatively" activated populations, as also known as M1 and M2 macrophages. M1 cells can lead to tissue injury and contribute to pathogenesis, whereas M2 cells promote angiogenesis, tissue remodeling, and repair. The aim of this study was to investigate the roles of M1 and M2 macrophages in a sporotrichosis model. Toward this end, we performed phenotyping of peritoneal exudate cells and evaluated the concomitant production of several immunomediators, including IL-12, IL-10, TGF-β, nitric oxide, and arginase-I activity, which were stimulated ex vivo with cell wall peptide-polysaccharide. Our results showed the predominance of the M2 macrophage population, indicated by peaks of arginase-I activity as well as IL-10 and TGF-β production during the 6th and 8th weeks after infection. These results were consistent with cellular phenotyping that revealed increases in CD206-positive cells over this period. This is the first report of the participation of M2 macrophages in sporotrichosis infections.
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Affiliation(s)
- Pamela Alegranci
- Department of Clinical Analysis, School of Pharmaceutical Sciences, Sao Paulo State University (UNESP), Rua Expedicionários do Brasil no 1621, Araraquara, SP, CEP 14801-902, Brazil
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5-Lipoxygenase activity increases susceptibility to experimental Paracoccidioides brasiliensis infection. Infect Immun 2013; 81:1256-66. [PMID: 23381993 DOI: 10.1128/iai.01209-12] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Paracoccidioidomycosis (PCM) is a systemic mycosis caused by the thermodimorphic fungus Paracoccidioides brasiliensis. Leukotrienes and lipoxins are lipid mediators produced after 5-lipoxygenase (5-LO) activation that exhibit pro- and anti-inflammatory roles, respectively. Here, we have investigated the contribution of 5-LO enzymatic activity in PCM using an experimental model of P. brasiliensis infection. B6.129 wild-type (B6.129) and 5-LO-deficient (5-LO(-/-)) mice were intravenously inoculated with a virulent strain of P. brasiliensis (Pb18), and the survival rate of the infected mice was investigated on different days after yeast infection. 5-LO(-/-) mice exhibited an increased survival rate associated with a decreased number of CFU. The resistance of 5-LO(-/-) during PCM was associated with augmented nitric oxide (NO) production and the formation of compact granulomas. In addition, the absence of 5-LO was associated with a diminished number of CD4(+) CD25(+) regulatory T cells, higher levels of gamma interferon and interleukin-12, and increased T-bet (a T-box transcription factor that directs Th1 lineage commitment) mRNA levels in the lungs. Taken together, our results show for the first time that 5-LO enzymatic activity increases susceptibility to P. brasiliensis, suggesting that this pathway may be a potential target for therapeutic intervention during PCM.
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Feriotti C, Loures FV, Frank de Araújo E, da Costa TA, Calich VLG. Mannosyl-recognizing receptors induce an M1-like phenotype in macrophages of susceptible mice but an M2-like phenotype in mice resistant to a fungal infection. PLoS One 2013; 8:e54845. [PMID: 23382985 PMCID: PMC3559829 DOI: 10.1371/journal.pone.0054845] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2012] [Accepted: 12/18/2012] [Indexed: 11/30/2022] Open
Abstract
In addition to alpha1,3 glucan, mannan and mannan-linked proteins are expressed in the outer layer of Paracoccidioides brasiliensis yeasts. The recognition of mannosyl residues by multiple pathogen recognition receptors, such as the mannose receptor (MR), complement receptor 3 (CR3) and toll-like receptor 4 (TLR4) on macrophage membranes can influence macrophage activation and the mechanisms of innate immunity against fungal pathogens. The aim of this study was to clarify the role of these receptors in the interaction between P. brasiliensis and macrophages from resistant (A/J) and susceptible (B10.A) mice. Therefore, the phagocytic, fungicidal and secretory abilities of macrophages were evaluated in the presence of mannan and antibodies against MR, CR3 and TLR4. We verified that mannan increased and anti-MR antibody decreased the killing ability and nitric oxide production of macrophages. The specific blockade of MR, CR3 and TLR4 by monoclonal antibodies impaired fungal recognition and modulated the production of cytokines. Mannan or P. brasiliensis induced decreased expression of MR and TLR2 on A/J macrophages, whereas CR3, TLR4 and TLR2 were reduced on B10.A cells. Importantly, both mannan and P. brasiliensis induced the production of IL-12 by B10.A macrophages, whereas TGF-β, TNF-α and IL-6 were produced by A/J cells. In addition, B10.A macrophages exhibited a prevalent expression of inducible NO-synthase and SOCS3 (suppressor of cytokine signaling-3), indicating a pro-inflammatory, "M1-like" differentiation. In contrast, the elevated expression of arginase-1, found in inflammatory zone-1 (FIZZ1), YM1 (CHI313, chitinase-like lectin), and SOCS1, typical markers of alternatively activated macrophages, indicates a prevalent "M2-like" differentiation of A/J macrophages. In conclusion, our data reveal that several mannosyl-recognizing receptors coordinate the apparently paradoxical innate response to paracoccidioidomycosis, in which resistance is initially mediated by alternatively activated phagocytes and tolerance to fungal growth, whereas susceptibility is linked to classically activated macrophages and the efficient control of fungal growth.
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Affiliation(s)
- Claudia Feriotti
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, São Paulo, Brazil
| | - Flávio V. Loures
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, São Paulo, Brazil
| | - Eliseu Frank de Araújo
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, São Paulo, Brazil
| | - Tania Alves da Costa
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, São Paulo, Brazil
| | - Vera L. G. Calich
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, São Paulo, Brazil
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Myeloid dendritic cells (DCs) of mice susceptible to paracoccidioidomycosis suppress T cell responses whereas myeloid and plasmacytoid DCs from resistant mice induce effector and regulatory T cells. Infect Immun 2013; 81:1064-77. [PMID: 23340311 DOI: 10.1128/iai.00736-12] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The protective adaptive immune response in paracoccidioidomycosis, a mycosis endemic among humans, is mediated by T cell immunity, whereas impaired T cell responses are associated with severe, progressive disease. The early host response to Paracoccidioides brasiliensis infection is not known since the disease is diagnosed at later phases of infection. Our laboratory established a murine model of infection where susceptible mice reproduce the severe disease, while resistant mice develop a mild infection. This work aimed to characterize the influence of dendritic cells in the innate and adaptive immunity of susceptible and resistant mice. We verified that P. brasiliensis infection induced in bone marrow-derived dendritic cells (DCs) of susceptible mice a prevalent proinflammatory myeloid phenotype that secreted high levels of interleukin-12 (IL-12), tumor necrosis factor alpha, and IL-β, whereas in resistant mice, a mixed population of myeloid and plasmacytoid DCs secreting proinflammatory cytokines and expressing elevated levels of secreted and membrane-bound transforming growth factor β was observed. In proliferation assays, the proinflammatory DCs from B10.A mice induced anergy of naïve T cells, whereas the mixed DC subsets from resistant mice induced the concomitant proliferation of effector and regulatory T cells (Tregs). Equivalent results were observed during pulmonary infection. The susceptible mice displayed preferential expansion of proinflammatory myeloid DCs, resulting in impaired proliferation of effector T cells. Conversely, the resistant mice developed myeloid and plasmacytoid DCs that efficiently expanded gamma interferon-, IL-4-, and IL-17-positive effector T cells associated with increased development of Tregs. Our work highlights the deleterious effect of excessive innate proinflammatory reactions and provides new evidence for the importance of immunomodulation during pulmonary paracoccidioidomycosis.
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Sargi SC, Dalalio MMDO, Visentainer JV, Bezerra RC, Perini JÂDL, Stevanato FB, Visentainer JEL. Production of TNF-α, nitric oxide and hydrogen peroxide by macrophages from mice with paracoccidioidomycosis that were fed a linseed oil-enriched diet. Mem Inst Oswaldo Cruz 2012; 107:303-9. [PMID: 22510824 DOI: 10.1590/s0074-02762012000300003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2011] [Accepted: 02/01/2012] [Indexed: 11/21/2022] Open
Abstract
Omega-3 polyunsaturated fatty acids (n-3 PUFA) can modulate the immune system and their primary effect is on macrophage function. Paracoccidioidomycosis (PCM) is an endemic systemic mycosis in Latin America that is caused by the dimorphic fungus Paracoccidioides brasiliensis (Pb). Macrophages are the main defence against this pathogen and have microbicidal activity that is dependent on interferon-Γ and tumour necrosis factor (TNF)-α. These cytokines stimulate the synthesis of nitric oxide (NO) and hydrogen peroxide (H₂O₂), leading to the death of the fungus. To study the effect of n-3 PUFA on the host immune response during experimental PCM, macrophages that were obtained from animals infected with Pb18 and fed a diet enriched by linseed (LIN) oil were cultured and challenged with the fungus in vitro. The macrophage function was analysed based on the concentrations of TNF-α, NO and H₂O₂. LIN oil seems to influence the production of TNF-α during the development of disease. A diet enriched with LIN oil influences the microbicidal activity of the macrophages by inducing the production of cytokines and metabolites such as NO and H₂O₂, predominantly in the chronic phase of infection.
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Affiliation(s)
- Sheisa Cyléia Sargi
- Laboratório de Imunogenética, Departamento de Ciências Básicas da Saúde, Universidade Estadual de Maringá, Maringá, PR, Brasil
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Anti-CD25 treatment depletes Treg cells and decreases disease severity in susceptible and resistant mice infected with Paracoccidioides brasiliensis. PLoS One 2012; 7:e51071. [PMID: 23226464 PMCID: PMC3511355 DOI: 10.1371/journal.pone.0051071] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2012] [Accepted: 10/30/2012] [Indexed: 12/31/2022] Open
Abstract
Regulatory T (Treg) cells are fundamental in the control of immunity and excessive tissue pathology. In paracoccidioidomycosis, an endemic mycosis of Latin America, the immunoregulatory mechanisms that control the progressive and regressive forms of this infection are poorly known. Due to its modulatory activity on Treg cells, we investigated the effects of anti-CD25 treatment over the course of pulmonary infection in resistant (A/J) and susceptible (B10.A) mice infected with Paracoccidioides brasiliensis. We verified that the resistant A/J mice developed higher numbers and more potent Treg cells than susceptible B10.A mice. Compared to B10.A cells, the CD4+CD25+Foxp3+ Treg cells of A/J mice expressed higher levels of CD25, CTLA4, GITR, Foxp3, LAP and intracellular IL-10 and TGF-β. In both resistant and susceptible mice, anti-CD25 treatment decreased the CD4+CD25+Foxp3+ Treg cell number, impaired indoleamine 2,3-dioxygenase expression and resulted in decreased fungal loads in the lungs, liver and spleen. In A/J mice, anti-CD25 treatment led to an early increase in T cell immunity, demonstrated by the augmented influx of activated CD4+ and CD8+ T cells, macrophages and dendritic cells to the lungs. At a later phase, the mild infection was associated with decreased inflammatory reactions and increased Th1/Th2/Th17 cytokine production. In B10.A mice, anti-CD25 treatment did not alter the inflammatory reactions but increased the fungicidal mechanisms and late secretion of Th1/Th2/Th17 cytokines. Importantly, in both mouse strains, the early depletion of CD25+ cells resulted in less severe tissue pathology and abolished the enhanced mortality observed in susceptible mice. In conclusion, this study is the first to demonstrate that anti-CD25 treatment is beneficial to the progressive and regressive forms of paracoccidioidomycosis, potentially due to the anti-CD25-mediated reduction of Treg cells, as these cells have suppressive effects on the early T cell response in resistant mice and the clearance mechanisms of fungal cells in susceptible mice.
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Effect of heat stress on cellular and humoral immunity and its cure with α-tocopherol in meat type birds. Livest Sci 2012. [DOI: 10.1016/j.livsci.2012.06.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Konno FTC, Maricato J, Konno AYC, Guereschi MG, Vivanco BC, Feitosa LDS, Mariano M, Lopes JD. Paracoccidioides brasiliensis GP43-derived peptides are potent modulators of local and systemic inflammatory response. Microbes Infect 2012; 14:517-27. [PMID: 22281666 DOI: 10.1016/j.micinf.2011.12.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2011] [Revised: 12/05/2011] [Accepted: 12/22/2011] [Indexed: 10/14/2022]
Abstract
Paracoccidioidomycosis is a systemic granulomatous disease caused by the dimorphic fungus Paracoccidioides brasiliensis. Its major antigen is a 43 kDa glycoprotein whose peptides embody different functions: P10 peptide, a T-cell epitope, induces protective response while P4 and P23 peptides inhibit both, macrophage functions and inflammatory reaction, thus facilitating infection. Here we investigated the modulating mechanisms of the immune response exerted by P4 and P23 involved in the latter inhibitory effect on macrophages. Moreover we analyzed the peptides effects in different models in vivo. While evaluating whether P4 and P23 present systemic anti-inflammatory effects in vivo, we showed that their intraperitonial administration decreased footpad swelling in mice infected with either P. brasiliensis or Mycobacterium bovis. Both, qPCR and ELISA assays suggested that this anti-inflammatory effect depended on alterations in the kinetics of production of innate immunity modulators such as TNF-α, IL6, IL10 and TLR2. IL10 seems to be early produced than TNF-α and IL6, produced later in presence of peptides. Higher doses or intravenously given P4 and P23 resulted in earlier and more prolonged anti-inflammatory effects. Moreover, continuous treatment with P4 and P23 sustained the anti-inflammatory activity throughout.
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Affiliation(s)
- Fabiana T C Konno
- Universidade Federal de São Paulo - UNIFESP, Department of Microbiology, Immunology and Parasitology, Discipline of Immunology, São Paulo, Brazil
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Arce-Fonseca M, Ramos-Ligonio A, López-Monteón A, Salgado-Jiménez B, Talamás-Rohana P, Rosales-Encina JL. A DNA vaccine encoding for TcSSP4 induces protection against acute and chronic infection in experimental Chagas disease. Int J Biol Sci 2011; 7:1230-8. [PMID: 22110377 PMCID: PMC3221361 DOI: 10.7150/ijbs.7.1230] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2011] [Accepted: 10/01/2011] [Indexed: 12/12/2022] Open
Abstract
Immunization of mice with plasmids containing genes of Trypanosoma cruzi induces protective immunity in the murine model of Chagas disease. A cDNA clone that codes for an amastigote-specific surface protein (TcSSP4) was used as a candidate to develop a DNA vaccine. Mice were immunized with the recombinant protein rTcSSP4 and with cDNA for TcSSP4, and challenged with bloodstream trypomastigotes. Immunization with rTcSSP4 protein makes mice more susceptible to trypomastigote infection, with high mortality rates, whereas mice immunized with a eukaryotic expression plasmid containing the TcSSP4 cDNA were able to control the acute phase of infection. Heart tissue of gene-vaccinated animals did not show myocarditis and tissue damage at 365 days following infection, as compared with control animals. INF-γ was detected in sera of DNA vaccinated mice shortly after immunization, suggesting the development of a Th1 response. The TcSSP4 gene is a promising candidate for the development of an anti-T. cruzi DNA vaccine.
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Affiliation(s)
- Minerva Arce-Fonseca
- Departamento de Infectómica y Patogenesis Molecular, Centro de Investigación y de Estudios Avanzados del I.P.N., México D.F. 07360, México
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Gonzalez A, Hung CY, Cole GT. Nitric oxide synthase activity has limited influence on the control of Coccidioides infection in mice. Microb Pathog 2011; 51:161-8. [PMID: 21513788 DOI: 10.1016/j.micpath.2011.03.013] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2011] [Revised: 02/28/2011] [Accepted: 03/02/2011] [Indexed: 11/20/2022]
Abstract
The functions of inducible nitric oxide synthase (iNOS) activity in protection against microbial insults are still controversial. In this study, we explored the role of iNOS in protection against Coccidioides infection in mice. We observed that wild type (WT) and iNOS(-/-) mice showed similar percent survival and fungal burden in their lungs at days 7 and 11 after intranasal challenge with Coccidioides. Vaccinated WT and iNOS(-/-) mice revealed comparable fungal burden in their lungs and spleen at 7 and 11 days postchallenge. However, at 11 days the non-vaccinated, iNOS-deficient mice had significantly higher fungal burden in their spleen compared to WT mice. Additionally, higher numbers of lung-infiltrated neutrophils, macrophages and dendritic cells were observed in WT mice at day 11 postchallenge compared to iNOS(-/-) mice. Moreover, no difference in numbers of T, B, NK or regulatory T cells, or concentrations of selected cytokines and chemokines were detected in lungs of both mouse strains at 7 and 11 days postchallenge. Although iNOS-derived NO production appears to influence the inflammatory response and dissemination of the fungal pathogen, our results suggest that iNOS activity does not play a significant role in the control of coccidioidal infection in mice and that other, still undefined mechanisms of host protection are involved.
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Affiliation(s)
- Angel Gonzalez
- Department of Biology and South Texas Center for Emerging Infectious Diseases, University of Texas at San Antonio, San Antonio, TX 78249, USA.
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Experimental chemotherapy in paracoccidioidomycosis using ruthenium NO donor. Mycopathologia 2011; 172:95-107. [PMID: 21437728 DOI: 10.1007/s11046-011-9416-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2010] [Accepted: 03/06/2011] [Indexed: 10/18/2022]
Abstract
Paracoccidioidomycosis (PCM) is a granulomatous disease caused by a dimorphic fungus, Paracoccidioides brasiliensis (Pb). To determine the influence of nitric oxide (NO) on this disease, we tested cis-[Ru(bpy)2(NO)SO3](PF6), ruthenium nitrosyl, which releases NO when activated by biological reducing agents, in BALB/c mice infected intravenously with Pb 18 isolate. In a previous study by our group, the fungicidal activity of ruthenium nitrosyl was evaluated in a mouse model of acute PCM, by measuring the immune cellular response (DTH), histopathological characteristics of the granulomatous lesions (and numbers), cytokines, and NO production. We found that cis-[Ru(bpy)2(NO)SO3](PF6)-treated mice were more resistant to infection, since they exhibited higher survival when compared with the control group. Furthermore, we observed a decreased influx of inflammatory cells in the lung and liver tissue of treated mice, possibly because of a minor reduction in fungal cell numbers. Moreover, an increased production of IL-10 and a decrease in TNF-α levels were detected in lung tissues of infected mice treated with cis-[Ru(bpy)2(NO)SO3](PF6). Immunohistochemistry showed that there was no difference in the number of VEGF- expressing cells. The animals treated with cis-[Ru(bpy)2(NO)SO3](PF6) showed high NO levels at 40 days after infection. These results show that NO is effectively involved in the mechanism that regulates the immune response in lung of Pb-infected mice. These data suggest that NO is a resistance factor during paracoccidioidomycosis by controlling fungal proliferation, influencing cytokine production, and consequently moderating the development of a strong inflammatory response.
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MyD88 signaling is required for efficient innate and adaptive immune responses to Paracoccidioides brasiliensis infection. Infect Immun 2011; 79:2470-80. [PMID: 21422180 DOI: 10.1128/iai.00375-10] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The mechanisms that govern the initial interaction between Paracoccidioides brasiliensis, a primary dimorphic fungal pathogen, and cells of the innate immunity need to be clarified. Our previous studies showed that Toll-like receptor 2 (TLR2) and TLR4 regulate the initial interaction of fungal cells with macrophages and the pattern of adaptive immunity that further develops. The aim of the present investigation was to assess the role of MyD88, an adaptor molecule used by TLRs to activate genes of the inflammatory response in pulmonary paracoccidioidomycosis. Studies were performed with normal and MyD88(-/-) C57BL/6 mice intratracheally infected with P. brasiliensis yeast cells. MyD88(-/-) macrophages displayed impaired interaction with fungal yeast cells and produced low levels of IL-12, MCP-1, and nitric oxide, thus allowing increased fungal growth. Compared with wild-type (WT) mice, MyD88(-/-) mice developed a more severe infection of the lungs and had marked dissemination of fungal cells to the liver and spleen. MyD88(-/-) mice presented low levels of Th1, Th2, and Th17 cytokines, suppressed lymphoproliferation, and impaired influx of inflammatory cells to the lungs, and this group of cells comprised lower numbers of neutrophils, activated macrophages, and T cells. Nonorganized, coalescent granulomas, which contained high numbers of fungal cells, characterized the severe lesions of MyD88(-/-) mice; the lesions replaced extensive areas of several organs. Therefore, MyD88(-/-) mice were unable to control fungal growth and showed a significantly decreased survival time. In conclusion, our findings demonstrate that MyD88 signaling is important in the activation of fungicidal mechanisms and the induction of protective innate and adaptive immune responses against P. brasiliensis.
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San-Blas G, Burger E. Experimental medical mycological research in Latin America - a 2000-2009 overview. Rev Iberoam Micol 2010; 28:1-25. [PMID: 21167301 DOI: 10.1016/j.riam.2010.11.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2010] [Revised: 11/24/2010] [Accepted: 11/24/2010] [Indexed: 11/26/2022] Open
Abstract
An overview of current trends in Latin American Experimental Medical Mycological research since the beginning of the 21(st) century is done (search from January 2000 to December 2009). Using the PubMed and LILACS databases, the authors have chosen publications on medically important fungi which, according to our opinion, are the most relevant because of their novelty, interest, and international impact, based on research made entirely in the Latin American region or as part of collaborative efforts with laboratories elsewhere. In this way, the following areas are discussed: 1) molecular identification of fungal pathogens; 2) molecular and clinical epidemiology on fungal pathogens of prevalence in the region; 3) cell biology; 4) transcriptome, genome, molecular taxonomy and phylogeny; 5) immunology; 6) vaccines; 7) new and experimental antifungals.
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Affiliation(s)
- Gioconda San-Blas
- Instituto Venezolano de Investigaciones Científicas, Caracas, Venezuela.
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Bannwart CF, Martins RAR, Nakaira-Takahashi É, Dias-Melício LA, Soares ÂMVC, Peraçoli MTS. Interleukin-15 augments oxidative metabolism and fungicidal activity of human monocytes against Paracoccidioides brasiliensis. Mem Inst Oswaldo Cruz 2010; 105:866-72. [DOI: 10.1590/s0074-02762010000700005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2010] [Accepted: 06/15/2010] [Indexed: 11/22/2022] Open
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CD28 exerts protective and detrimental effects in a pulmonary model of paracoccidioidomycosis. Infect Immun 2010; 78:4922-35. [PMID: 20713624 DOI: 10.1128/iai.00297-10] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
T-cell immunity has been claimed as the main immunoprotective mechanism against Paracoccidioides brasiliensis infection, the most important fungal infection in Latin America. As the initial events that control T-cell activation in paracoccidioidomycosis (PCM) are not well established, we decided to investigate the role of CD28, an important costimulatory molecule for the activation of effector and regulatory T cells, in the immunity against this pulmonary pathogen. Using CD28-deficient (CD28(-/-)) and normal wild-type (WT) C57BL/6 mice, we were able to demonstrate that CD28 costimulation determines in pulmonary paracoccidioidomycosis an early immunoprotection but a late deleterious effect associated with impaired immunity and uncontrolled fungal growth. Up to week 10 postinfection, CD28(-/-) mice presented increased pulmonary and hepatic fungal loads allied with diminished production of antibodies and pro- and anti-inflammatory cytokines besides impaired activation and migration of effector and regulatory T (Treg) cells to the lungs. Unexpectedly, CD28-sufficient mice progressively lost the control of fungal growth, resulting in an increased mortality associated with persistent presence of Treg cells, deactivation of inflammatory macrophages and T cells, prevalent presence of anti-inflammatory cytokines, elevated fungal burdens, and extensive hepatic lesions. As a whole, our findings suggest that CD28 is required for the early protective T-cell responses to P. brasiliensis infection, but it also induces the expansion of regulatory circuits that lately impair adaptive immunity, allowing uncontrolled fungal growth and overwhelming infection, which leads to precocious mortality of mice.
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Nishikaku AS, Scavone R, Molina RFS, Albe BP, Cunha CDS, Burger E. Osteopontin involvement in granuloma formation and in the severity of Paracoccidioides brasiliensis infection. Med Mycol 2010; 47:495-507. [PMID: 19048431 DOI: 10.1080/13693780802342537] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
The participation of osteopontin (OPN) in Paracoccidioides brasiliensis infected mice, its association to granulomatogenesis, severity of infection, pattern of lesions, nitric oxide (NO) levels and fungal load were evaluated in this investigation. Immunohistochemistry analysis showed marked OPN staining in extracellular matrix and in macrophages and multinucleated giant cells at the center of lesions, suggesting a possible role of OPN in the distribution of these cells within the granulomas. At 15 days post-infection with a virulent P. brasiliensis isolate, OPN+ cells were more numerous and intensely immunostained in the loose granulomas of susceptible mice than in those of resistant mice. In addition, high fungal loads and low NO levels were observed in susceptible mice. At 120 days after infection, resistant mice had increased total OPN levels (ELISA) and OPN positivity in compact granulomas, higher NO levels and lower fungal loads than susceptible mice. Residual lesions associated with low OPN levels, high NO and control of fungal dissemination were observed in both mouse strains at 120 days post-infection with the slightly virulent fungal isolate. Therefore, OPN could be associated with higher severity of the disease in an early phase of infection and with a degree of control of the progressive infection.
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Affiliation(s)
- Angela Satie Nishikaku
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, Cidade Universitária, São Paulo-SP, Brazil
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Davicino R, Micucci P, Zettler G, Ferraro G, Anesini C. "In vivo" murine macrophages activation by a dichloromethane extract of Tilia x viridis. Immunopharmacol Immunotoxicol 2010; 32:473-80. [PMID: 20095811 DOI: 10.3109/08923970903520993] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Macrophages are involved in the host defense against infectious pathogens and tumors. Tilia species have been used in folk medicine for the treatment of infectious diseases, previously it was demonstrated that a dichloromethane (DM) extract possess antiproliferative action "in vitro" on a lymphoma cell line. The aim of this work was to study the "in vivo" effect of DM extract upon mice peritoneal macrophages. DM extract-activated macrophages phagocytosis through hydrogen peroxide (H(2)O(2)) and nitric oxide (NO) production (phagocytosis (%): basal 16.93 +/- 0.18, DM extract 25.93 +/- 2.8; H(2)O(2) (M): basal 0.0022 +/- 0.00016, DM extract 0.0036 +/- 0.0005; NO (mM): basal 0.0052 +/- 0.0007, DM extract 0.0099 +/- 0.0004). These actions were mediated by cell superoxide dismutase activation. On the other hand, DM extract decreased tumor necrosis factor alpha but increased interleukin-10 in serum. These results suggest that the modulation activity exerted by the extract on immune system cells could be an important mechanism to acquire resistance to tumors and infectious diseases.
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Affiliation(s)
- Roberto Davicino
- IQUIMEFA (UBA- CONICET), Pharmacology Department, Faculty of Pharmacy and Biochemistry, University of Buenos Aires, Buenos Aires, Argentina.
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Alves CC, Azevedo AL, Rodrigues MF, Machado RP, Souza MA, Machado MA, Teixeira HC, Ferreira AP. Cellular and humoral immune responses during intrathoracic paracoccidioidomycosis in BALB/c mice. Comp Immunol Microbiol Infect Dis 2009; 32:513-25. [DOI: 10.1016/j.cimid.2008.07.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/15/2008] [Indexed: 10/21/2022]
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Nishikaku AS, Molina RFS, Ribeiro LC, Scavone R, Albe BP, Cunha CS, Burger E. Nitric oxide participation in granulomatous response induced by Paracoccidioides brasiliensis infection in mice. Med Microbiol Immunol 2009; 198:123-35. [PMID: 19360439 DOI: 10.1007/s00430-009-0113-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2008] [Indexed: 10/20/2022]
Abstract
The role of nitric oxide (NO) in granulomas of Paracoccidioides brasiliensis-infected inducible NO synthase-deficient C57BL/6 mice (iNOS KO) and their wild-type counterparts and its association with osteopontin (OPN) and matrix metalloproteinases (MMPs) was studied. At 15 days after infection (DAI), iNOS KO mice showed compact and necrotic granulomas with OPN+ macrophages and multinucleated giant cells, whereas wild-type mice developed loose granulomas with many fungi and OPN+ cells distributed throughout the tissue. In addition, high OPN levels and fungal load were observed in iNOS KO mice. Both experimental groups had MMP-9 activity. At 120 DAI, iNOS KO had smaller granulomas with OPN+ cells, lower OPN levels, lower fungal load and decreased MMP-9 activity compared with wild-type mice. These findings suggest that NO has an important role in granuloma modulation, by controlling OPN and MMP production, as well as by inducing loose granulomas formation and fungal dissemination, resulting, at later phases, in progression of paracoccidioidomycosis.
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Affiliation(s)
- Angela Satie Nishikaku
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, Avenida Professor Lineu Prestes, 1730, Cidade Universitária, São Paulo 05508-900, Brazil
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Lopera D, Aristizabal BH, Restrepo A, Cano LE, González A. Lysozyme plays a dual role against the dimorphic fungus Paracoccidioides brasiliensis. Rev Inst Med Trop Sao Paulo 2008; 50:169-75. [PMID: 18604417 DOI: 10.1590/s0036-46652008000300008] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2007] [Accepted: 04/14/2008] [Indexed: 11/22/2022] Open
Abstract
In order to determine the role of lysozyme, an antimicrobial peptide belonging to the innate immune system, against the dimorphic fungus Paracoccidioides brasiliensis, co-cultures of the MH-S murine alveolar macrophages cell line with P. brasiliensis conidia were done; assays to evaluate the effect of physiological and inflammatory concentrations of lysozyme directly on the fungus life cycle were also undertaken. We observed that TNF-alpha-activated macrophages significantly inhibited the conidia to yeast transition (p = 0.0043) and exerted an important fungicidal effect (p = 0.0044), killing 27% more fungal propagules in comparison with controls. Nonetheless, after adding a selective inhibitor of lysozyme, the fungicidal effect was reverted. When P. brasiliensis propagules were exposed directly to different concentrations of lysozyme, a dual effect was observed. Physiologic concentrations of the enzyme facilitated the conidia-to-yeast transition process (p < 0.05). On the contrary, inflammatory concentrations impaired the normal temperature-dependent fungal transition (p < 0.0001). When yeast cells were exposed to lysozyme, irrespective of concentration, the multiple-budding ability was badly impaired (p < 0.0001). In addition, ultra-structural changes such as subcellular degradation, fusion of lipid vacuoles, lamellar structures and interruption of the fibrillar layer were observed in lysozyme exposed conidia. These results suggest that lysozyme appears to exert a dual role as part of the anti-P. brasiliensis defense mechanisms.
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Affiliation(s)
- Damaris Lopera
- Medical and Experimental Mycology Group, Corporación para Investigaciones Biológicas, Carrera 72A No. 78B-141, Medellín, Colombia
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Coltri KC, Oliveira LL, Pinzan CF, Vendruscolo PE, Martinez R, Goldman MH, Panunto-Castelo A, Roque-Barreira MC. Therapeutic administration of KM+ lectin protects mice against Paracoccidioides brasiliensis infection via interleukin-12 production in a toll-like receptor 2-dependent mechanism. THE AMERICAN JOURNAL OF PATHOLOGY 2008; 173:423-32. [PMID: 18599609 DOI: 10.2353/ajpath.2008.080126] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
KM(+) is a mannose-binding lectin from Artocarpus integrifolia that induces interleukin (IL)-12 production by macrophages and protective T helper 1 immune response against Leishmania major infection. In this study, we performed experiments to evaluate the therapeutic activity of jackfruit KM(+) (jfKM(+)) and its recombinant counterpart (rKM(+)) in experimental paracoccidioidomycosis. To this end, jfKM(+) or rKM(+) was administered to BALB/c mice 10 days after infection with Paracoccidiodes brasiliensis. Thirty days postinfection, lungs from the KM(+)-treated mice contained significantly fewer colony-forming units and little to no organized granulomas compared to the controls. In addition, lung homogenates from the KM(+)-treated mice presented higher levels of nitric oxide, IL-12, interferon-gamma, and tumor necrosis factor-alpha, whereas higher levels of IL-4 and IL-10 were detected in the control group. With mice deficient in IL-12, Toll-like receptor (TLR) 2, TLR4, or TLR adaptor molecule MyD88, we demonstrated that KM(+) led to protection against P. brasiliensis infection through IL-12 production, which was dependent on TLR2. These results demonstrated a beneficial effect of KM(+) on the severity of P. brasiliensis infection and may expand its potential use as a novel immunotherapeutic molecule.
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Affiliation(s)
- Kely C Coltri
- Departamento de Biologia Celular e Molecular e Bioagentes Patogênicos, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, 14049-900-Ribeirão Preto, São Paulo, Brazil
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Moreira AP, Dias-Melicio LA, Peraçoli MTS, Calvi SA, Victoriano de Campos Soares AM. Killing of Paracoccidioides brasiliensis yeast cells by IFN-gamma and TNF-alpha activated murine peritoneal macrophages: evidence of H(2)O (2) and NO effector mechanisms. Mycopathologia 2008; 166:17-23. [PMID: 18496766 DOI: 10.1007/s11046-007-9046-3] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2007] [Accepted: 07/25/2007] [Indexed: 11/24/2022]
Abstract
Paracoccidioidomycosis is a deep mycosis, endemic in Latin America, caused by Paracoccidioides brasiliensis. Macrophage activation by cytokines is the major effector mechanism against this fungus. This work aimed at a better understanding of the interaction between yeast cells-murine peritoneal macrophages and the cytokine signals required for the effective killing of high virulence yeast-form of P. brasiliensis. In addition, the killing effector mechanisms dependent on the generation of reactive oxygen or nitrogen intermediates were investigated. Cell preincubation with IFN-gamma or TNF-alpha, at adequate doses, resulted in effective yeast killing as demonstrated in short-term (4-h) assays. Both, IFN-gamma and TNF-alpha activation were associated with higher levels of H(2)O(2) and NO when compared to nonactivation. Treatment with catalase (CAT), a H(2)O(2 )scavenger, and N(G)-monomethyl-L: -arginine (L: -NMMA), a nitric oxide synthase inhibitor, reverted the killing effect of activated cells. Taken together, these results suggest that both oxygen and L: -arginine-nitric oxide pathways play a role in the killing of highly virulent P. brasiliensis.
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Affiliation(s)
- Ana Paula Moreira
- Department of Microbiology and Immunology, Biosciences Institute, UNESP, Rubião Júnior, Botucatu, São Paulo, CEP 18618-000, Brazil
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Pulmonary immune responses induced in BALB/c mice by Paracoccidioides brasiliensis conidia. Mycopathologia 2008; 165:313-30. [DOI: 10.1007/s11046-007-9072-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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