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de Oliveira TC, Freyria NJ, Sarmiento-Villamil JL, Porth I, Tanguay P, Bernier L. Unraveling the transcriptional features and gene expression networks of pathogenic and saprotrophic Ophiostoma species during the infection of Ulmus americana. Microbiol Spectr 2024; 12:e0369423. [PMID: 38230934 PMCID: PMC10845970 DOI: 10.1128/spectrum.03694-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Accepted: 12/08/2023] [Indexed: 01/18/2024] Open
Abstract
American elm (Ulmus americana), highly prized for its ornamental value, has suffered two successive outbreaks of Dutch elm disease (DED) caused by ascomycete fungi belonging to the genus Ophiostoma. To identify the genes linked to the pathogenicity of different species and lineages of Ophiostoma, we inoculated 2-year-old U. americana saplings with six strains representing three species of DED fungi, and one strain of the saprotroph Ophiostoma quercus. Differential expression analyses were performed following RNA sequencing of fungal transcripts recovered at 3- and 10-days post-infection. Based on a total of 8,640 Ophiostoma genes, we observed a difference in fungal gene expression depending on the strain inoculated and the time of incubation in host tissue. Some genes overexpressed in the more virulent strains of Ophiostoma encode hydrolases that possibly act synergistically. A mutant of Ophiostoma novo-ulmi in which the gene encoding the ogf1 transcription factor had been deleted did not produce transcripts for the gene encoding the hydrophobin cerato-ulmin and was less virulent. Weighted gene correlation network analyses identified several candidate pathogenicity genes distributed among 13 modules of interconnected genes.IMPORTANCEOphiostoma is a genus of cosmopolitan fungi that belongs to the family Ophiostomataceae and includes the pathogens responsible for two devastating pandemics of Dutch elm disease (DED). As the mechanisms of action of DED agents remain unclear, we carried out the first comparative transcriptomic study including representative strains of the three Ophiostoma species causing DED, along with the phylogenetically close saprotrophic species Ophiostoma quercus. Statistical analyses of the fungal transcriptomes recovered at 3 and 10 days following infection of Ulmus americana saplings highlighted several candidate genes associated with virulence and host-pathogen interactions wherein each strain showed a distinct transcriptome. The results of this research underscore the importance of investigating the transcriptional behavior of different fungal taxa to understand their pathogenicity and virulence in relation to the timeline of infection.
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Affiliation(s)
- Thais C. de Oliveira
- Institut de Biologie Intégrative et des Systèmes, Université Laval, Québec, Quebec, Canada
- Centre d’étude de la Forêt, Faculté de foresterie, de géographie et de géomatique, Université Laval, Québec, Quebec, Canada
| | - Nastasia J. Freyria
- Department of Natural Resource Sciences, McGill University, St. Anne-de-Bellevue, Quebec, Quebec, Canada
| | - Jorge Luis Sarmiento-Villamil
- Institut de Biologie Intégrative et des Systèmes, Université Laval, Québec, Quebec, Canada
- Centre d’étude de la Forêt, Faculté de foresterie, de géographie et de géomatique, Université Laval, Québec, Quebec, Canada
- Instituto de Hortofruticultura Subtropical y Mediterránea, Consejo Superior de Investigaciones Científicas-Universidad de Málaga (IHSM-CSIC-UMA), Estación Experimental “La Mayora”, Málaga, Spain
| | - Ilga Porth
- Institut de Biologie Intégrative et des Systèmes, Université Laval, Québec, Quebec, Canada
- Centre d’étude de la Forêt, Faculté de foresterie, de géographie et de géomatique, Université Laval, Québec, Quebec, Canada
| | - Philippe Tanguay
- Canadian Forest Service, Natural Resources Canada, Laurentian Forestry Centre, Québec, Quebec, Canada
| | - Louis Bernier
- Institut de Biologie Intégrative et des Systèmes, Université Laval, Québec, Quebec, Canada
- Centre d’étude de la Forêt, Faculté de foresterie, de géographie et de géomatique, Université Laval, Québec, Quebec, Canada
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Romero V, Kalinhoff C, Saa LR, Sánchez A. Fungi's Swiss Army Knife: Pleiotropic Effect of Melanin in Fungal Pathogenesis during Cattle Mycosis. J Fungi (Basel) 2023; 9:929. [PMID: 37755037 PMCID: PMC10532448 DOI: 10.3390/jof9090929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 09/05/2023] [Accepted: 09/08/2023] [Indexed: 09/28/2023] Open
Abstract
Fungal threats to public health, food security, and biodiversity have escalated, with a significant rise in mycosis cases globally. Around 300 million people suffer from severe fungal diseases annually, while one-third of food crops are decimated by fungi. Vertebrate, including livestock, are also affected. Our limited understanding of fungal virulence mechanisms hampers our ability to prevent and treat cattle mycoses. Here we aim to bridge knowledge gaps in fungal virulence factors and the role of melanin in evading bovine immune responses. We investigate mycosis in bovines employing a PRISMA-based methodology, bioinformatics, and data mining techniques. Our analysis identified 107 fungal species causing mycoses, primarily within the Ascomycota division. Candida, Aspergillus, Malassezia, and Trichophyton were the most prevalent genera. Of these pathogens, 25% produce melanin. Further research is required to explore the involvement of melanin and develop intervention strategies. While the literature on melanin-mediated fungal evasion mechanisms in cattle is lacking, we successfully evaluated the transferability of immunological mechanisms from other model mammals through homology. Bioinformatics enables knowledge transfer and enhances our understanding of mycosis in cattle. This synthesis fills critical information gaps and paves the way for proposing biotechnological strategies to mitigate the impact of mycoses in cattle.
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Affiliation(s)
- Víctor Romero
- Maestría en Biotecnología Agropecuaria, Universidad Técnica Particular de Loja, San Cayetano Alto, Calle París s/n, Loja 1101608, Ecuador
- Museo de Zoología, Universidad Técnica Particular de Loja, San Cayetano Alto, Calle París s/n, Loja 1101608, Ecuador
| | - Carolina Kalinhoff
- Departamento de Ciencias Biológicas y Agropecuarias, Facultad de Ciencias Exactas y Naturales, Universidad Técnica Particular de Loja, San Cayetano Alto, Calle París s/n, Loja 1101608, Ecuador; (C.K.)
| | - Luis Rodrigo Saa
- Departamento de Ciencias Biológicas y Agropecuarias, Facultad de Ciencias Exactas y Naturales, Universidad Técnica Particular de Loja, San Cayetano Alto, Calle París s/n, Loja 1101608, Ecuador; (C.K.)
| | - Aminael Sánchez
- Departamento de Ciencias Biológicas y Agropecuarias, Facultad de Ciencias Exactas y Naturales, Universidad Técnica Particular de Loja, San Cayetano Alto, Calle París s/n, Loja 1101608, Ecuador; (C.K.)
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3
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Goughenour KD, Zhao J, Xu J, Zhao ZP, Ganguly A, Freeman CM, Olszewski MA. Murine Inducible Nitric Oxide Synthase Expression Is Essential for Antifungal Defenses in Kidneys during Disseminated Cryptococcus deneoformans Infection. J Immunol 2021; 207:2096-2106. [PMID: 34479942 DOI: 10.4049/jimmunol.2100386] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Accepted: 08/04/2021] [Indexed: 12/11/2022]
Abstract
Disseminated cryptococcosis has a nearly 70% mortality, mostly attributed to CNS infection, with lesser-known effects on other organs. Immune protection against Cryptococcus relies on Th1 immunity with M1 polarization, rendering macrophages fungicidal. The importance of M1-upregulated inducible NO synthase (iNOS) has been documented in pulmonary anticryptococcal defenses, whereas its role in disseminated cryptococcosis remains controversial. Here we examined the effect of iNOS deletion in disseminated (i.v.) C. deneoformans 52D infection, comparing wild-type (C57BL/6J) and iNOS-/- mice. iNOS-/- mice had significantly reduced survival and nearly 100-fold increase of the kidney fungal burden, without increases in the lungs, spleen, or brain. Histology revealed extensive lesions and almost complete destruction of the kidney cortical area with a loss of kidney function. The lack of fungal control was not due to a failure to recruit immune cells because iNOS-/- mice had increased kidney leukocytes. iNOS-/- mice also showed no defect in T cell polarization. We conclude that iNOS is critically required for local anticryptococcal defenses in the kidneys, whereas it appears to be dispensable in other organs during disseminated infection. This study exemplifies a unique phenotype of local immune defenses in the kidneys and the organ-specific importance of a single fungicidal pathway.
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Affiliation(s)
- Kristie D Goughenour
- Research Service, VA Ann Arbor Healthcare System, Department of Veterans Affairs Health System, Ann Arbor, MI.,Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Health System, Ann Arbor, MI; and
| | - Jessica Zhao
- Research Service, VA Ann Arbor Healthcare System, Department of Veterans Affairs Health System, Ann Arbor, MI.,Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Health System, Ann Arbor, MI; and
| | - Jintao Xu
- Research Service, VA Ann Arbor Healthcare System, Department of Veterans Affairs Health System, Ann Arbor, MI.,Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Health System, Ann Arbor, MI; and
| | - Ziyin P Zhao
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Health System, Ann Arbor, MI; and
| | - Anutosh Ganguly
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Health System, Ann Arbor, MI; and.,Department of Surgery, University of Michigan, Ann Arbor, MI
| | - Christine M Freeman
- Research Service, VA Ann Arbor Healthcare System, Department of Veterans Affairs Health System, Ann Arbor, MI.,Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Health System, Ann Arbor, MI; and
| | - Michal A Olszewski
- Research Service, VA Ann Arbor Healthcare System, Department of Veterans Affairs Health System, Ann Arbor, MI; .,Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Health System, Ann Arbor, MI; and
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Basso AMM, De Castro RJA, de Castro TB, Guimarães HI, Polez VLP, Carbonero ER, Pomin VH, Hoffmann C, Grossi-de-Sa MF, Tavares AH, Bocca AL. Immunomodulatory activity of β-glucan-containing exopolysaccharides from Auricularia auricular in phagocytes and mice infected with Cryptococcus neoformans. Med Mycol 2020; 58:227-239. [PMID: 31095342 DOI: 10.1093/mmy/myz042] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 04/01/2019] [Accepted: 04/12/2019] [Indexed: 12/19/2022] Open
Abstract
Current antifungal drugs present poor effectiveness and there is no available vaccine for fungal infections. Thus, novel strategies to treat or prevent invasive mycosis, such as cryptococcosis, are highly desirable. One strategy is the use of immunomodulators of polysaccharide nature isolated from mushrooms. The purpose of the present work was to evaluate the immunostimulatory activity of β-(1,3)-glucan-containing exopolysaccharides (EPS) from the edible mushrooms Auricularia auricula in phagocytes and mice infected with Cryptococcus neoformans. EPS triggered macrophages and dendritic cell activation upon binding to Dectin-1, a pattern recognition receptor of the C-type lectin receptor family. Engagement of Dectin-1 culminated in pro-inflammatory cytokine production and cell maturation via its canonical Syk-dependent pathway signaling. Furthermore, upon EPS treatment, M2-like phenotype macrophages, known to support intracellular survival and replication of C. neoformans, repolarize to M1 macrophage pattern associated with enhanced production of the microbicidal molecule nitric oxide that results in efficient killing of C. neoformans. Treatment with EPS also upregulated transcript levels of genes encoding products associated with host protection against C. neoformans and Dectin-1 mediated signaling in macrophages. Finally, orally administrated β-glucan-containing EPS from A. auricular enhanced the survival of mice infected with C. neoformans. In conclusion, the results demonstrate that EPS from A. auricula exert immunostimulatory activity in phagocytes and induce host protection against C. neoformans, suggesting that polysaccharides from this mushroom may be promising as an adjuvant for vaccines or antifungal therapy.
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Affiliation(s)
- A M M Basso
- Department of Cell Biology, Institute of Biological Sciences, University of Brasília, UnB, Brasilia, DF, Brazil
| | - R J A De Castro
- Department of Cell Biology, Institute of Biological Sciences, University of Brasília, UnB, Brasilia, DF, Brazil
| | - T B de Castro
- Department of Cell Biology, Institute of Biological Sciences, University of Brasília, UnB, Brasilia, DF, Brazil
| | - H I Guimarães
- Embrapa Genetic Resources and Biotechnology, Brasília, Brazil
| | - V L P Polez
- Embrapa Genetic Resources and Biotechnology, Brasília, Brazil
| | - E R Carbonero
- Department of Chemistry, Federal University of Goiás, Campus Catalão, GO, Brazil
| | - V H Pomin
- Program of Glicobiology, Institute of Medical Biochemistry Leopoldo de Meis, Federal University Federal of Rio de Janeiro, RJ, Brazil.,Department of BioMolecular Sciences, Division of Pharmacognosy and Research Institute of Pharmaceutical Sciences, School of Pharmacy, the University of Mississippi, Oxford, MS 38677-1848, USA
| | - C Hoffmann
- Department of Food Sciences and Experimental Nutrition, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - M F Grossi-de-Sa
- Embrapa Genetic Resources and Biotechnology, Brasília, Brazil.,Graduated Program in Genomic Science and Biotechnology, Catholic University of Brasília, Brasília, DF, Brazil
| | - A H Tavares
- Department of Cell Biology, Institute of Biological Sciences, University of Brasília, UnB, Brasilia, DF, Brazil
| | - A L Bocca
- Department of Cell Biology, Institute of Biological Sciences, University of Brasília, UnB, Brasilia, DF, Brazil
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Oliveira-Brito PKM, Rezende CP, Almeida F, Roque-Barreira MC, da Silva TA. iNOS/Arginase-1 expression in the pulmonary tissue over time during Cryptococcus gattii infection. Innate Immun 2019; 26:117-129. [PMID: 31446837 PMCID: PMC7016403 DOI: 10.1177/1753425919869436] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Inhalation of Cryptococcus gattii yeasts (causing cryptococcosis) triggers an anti-cryptococcal immune response initiated by macrophages, neutrophils or dendritic cells, and the iNOS expressed by various cells may regulate the function and differentiation of innate and adaptive immune cells. Here, we evaluated the effect of progression of C. gattii infection on the host innate immune response. C. gattii infection in BALB/c mice spreads to several organs by 21 d post infection. The numbers of neutrophils and lymphocytes in the peripheral blood of C. gattii–infected mice were remarkably altered on that day. The frequency of CD11b+ cells and cell concentrations of CD4+ and CD8+ T cells was significantly altered in the pulmonary tissue of infected mice. We found a higher frequency of CD11b+/iNOS+ cells in the lungs of infected mice, accompanied by an increase in frequency of CD11b+/Arginase-1+ cells over time. Moreover, the iNOS/Arginase-1 expression ratio in CD11b+ cells reached its lowest value at 21 d post infection. In addition, the cytokine micro-environment in infected lungs did not show a pro-inflammatory profile. Surprisingly, iNOS knock-out prolonged the survival of infected mice, while their pulmonary fungal burden was higher than that of infected WT mice. Thus, C. gattii infection alters the immune response in the pulmonary tissue, and iNOS expression may play a key role in infection progression.
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Affiliation(s)
- Patrícia Kellen Martins Oliveira-Brito
- Department of Cell and Molecular Biology and Pathogenic Bioagents, Ribeirão Preto Medical School, University of São Paulo, Brazil.,These authors contributed equally to this work
| | - Caroline Patini Rezende
- Department of Biochemistry and Immunology, Ribeirao Preto Medical School, University of São Paulo, Brazil.,These authors contributed equally to this work
| | - Fausto Almeida
- Department of Biochemistry and Immunology, Ribeirao Preto Medical School, University of São Paulo, Brazil
| | - Maria Cristina Roque-Barreira
- Department of Cell and Molecular Biology and Pathogenic Bioagents, Ribeirão Preto Medical School, University of São Paulo, Brazil
| | - Thiago Aparecido da Silva
- Department of Cell and Molecular Biology and Pathogenic Bioagents, Ribeirão Preto Medical School, University of São Paulo, Brazil
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Nakamura Y, Sato K, Yamamoto H, Matsumura K, Matsumoto I, Nomura T, Miyasaka T, Ishii K, Kanno E, Tachi M, Yamasaki S, Saijo S, Iwakura Y, Kawakami K. Dectin-2 deficiency promotes Th2 response and mucin production in the lungs after pulmonary infection with Cryptococcus neoformans. Infect Immun 2015; 83:671-81. [PMID: 25422263 DOI: 10.1128/IAI.02835-14] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Dectin-2 is a C-type lectin receptor that recognizes high mannose polysaccharides. Cryptococcus neoformans, a yeast-form fungal pathogen, is rich in polysaccharides in its cell wall and capsule. In the present study, we analyzed the role of Dectin-2 in the host defense against C. neoformans infection. In Dectin-2 gene-disrupted (knockout) (Dectin-2KO) mice, the clearance of this fungus and the inflammatory response, as shown by histological analysis and accumulation of leukocytes in infected lungs, were comparable to those in wild-type (WT) mice. The production of type 2 helper T (Th2) cytokines in lungs was higher in Dectin-2KO mice than in WT mice after infection, whereas there was no difference in the levels of production of Th1, Th17, and proinflammatory cytokines between these mice. Mucin production was significantly increased in Dectin-2KO mice, and this increase was reversed by administration of anti-interleukin 4 (IL-4) monoclonal antibody (MAb). The levels of expression of β1-defensin, cathelicidin, surfactant protein A (Sp-A), and Sp-D in infected lungs were comparable between these mice. In in vitro experiments, IL-12p40 and tumor necrosis factor alpha (TNF-α) production and expression of CD86 and major histocompatibility complex (MHC) class II by bone marrow-derived dendritic cells and alveolar macrophages were completely abrogated in Dectin-2KO mice. Finally, the disrupted lysates of C. neoformans, but not of whole yeast cells, activated Dectin-2-triggered signaling in an assay with nuclear factor of activated T cells (NFAT)-green fluorescent protein (GFP) reporter cells expressing this receptor. These results suggest that Dectin-2 may oppose the Th2 response and IL-4-dependent mucin production in the lungs after infection with C. neoformans, and it may not be required for the production of Th1, Th17, and proinflammatory cytokines or for clearance of this fungal pathogen.
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Turner C, Bilgin H, Obay B, Diken H, Tasdemir E, Atmaca M. Macrorhage Phagocytic Activity at Acute Cold-Restraint Stress Exposed Rats: Possible Role of Nitric Oxide. BIOTECHNOL BIOTEC EQ 2014. [DOI: 10.1080/13102818.2005.10817241] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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Silveira CP, Piffer AC, Kmetzsch L, Fonseca FL, Soares DA, Staats CC, Rodrigues ML, Schrank A, Vainstein MH. The heat shock protein (Hsp) 70 of Cryptococcus neoformans is associated with the fungal cell surface and influences the interaction between yeast and host cells. Fungal Genet Biol 2013; 60:53-63. [PMID: 23954835 DOI: 10.1016/j.fgb.2013.08.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Revised: 08/01/2013] [Accepted: 08/08/2013] [Indexed: 01/03/2023]
Abstract
The pathogenic yeast Cryptococcus neoformans secretes numerous proteins, such as heat shock proteins, by unconventional mechanisms during its interaction with host cells. Hsp70 is a conserved chaperone that plays important roles in various cellular processes, including the interaction of fungi with host immune cells. Here, we report that sera from individuals with cryptococcosis infection recognize a recombinant C. neoformans Hsp70 (Cn_rHsp70). Moreover, immunofluorescence assays using antibodies against Cn_rHsp70 revealed the localization of this protein at the cell surface mainly in association with the capsular network. We found that the addition of Cn_rHsp70 positively modulated the interaction of C. neoformans with human alveolar epithelial cells and decreased fungal killing by mouse macrophages, without affecting phagocytosis rates. Immunofluorescence analysis showed that there was a competitive association among the receptor, GXM and Cn_rHsp70, indicating that the Hsp70-binding sites in host cells appear to be shared by glucuronoxylomannan (GXM), the major capsular antigen in C. neoformans. Our observations suggest additional mechanisms by which Hsp70 influences the interaction of C. neoformans with host cells.
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Affiliation(s)
- Carolina P Silveira
- Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
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Szczytkowski JL, Lebonville C, Hutson L, Fuchs RA, Lysle DT. Heroin-induced conditioned immunomodulation requires expression of IL-1β in the dorsal hippocampus. Brain Behav Immun 2013; 30:95-102. [PMID: 23357470 PMCID: PMC3641184 DOI: 10.1016/j.bbi.2013.01.076] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2012] [Revised: 01/14/2013] [Accepted: 01/14/2013] [Indexed: 12/31/2022] Open
Abstract
Opioid-associated environmental stimuli elicit robust immune-altering effects via stimulation of a neural circuitry that includes the basolateral amygdala and nucleus accumbens. These brain regions are known to have both direct and indirect connections with the hippocampus. Thus, the present study evaluated whether the dorsal hippocampus (DH), and more specifically interleukin-1 beta (IL-1β) within the DH, is necessary for the expression of heroin-induced conditioned immunomodulation. Rats received five Pavlovian pairings of systemic heroin administration (1.0mg/kg, SC) with placement into a distinct environment (conditioned stimulus, CS). Six days after conditioning, a GABAA/B agonist cocktail or IL-1β small interfering RNA (siRNA) was microinfused into the DH to inhibit neuronal activity or IL-1β gene expression prior to CS or home cage exposure. Control animals received saline or negative control siRNA microinfusions. Furthermore, all rats received systemic administration of lipopolysaccharide (LPS) to stimulate proinflammatory nitric oxide production. CS exposure suppressed LPS-induced nitric oxide production relative to home cage exposure. Inactivation of, or IL-1β silencing in, the DH disrupted the CS-induced suppression of nitric oxide production relative to vehicle or negative control siRNA treatment. These results are the first to show a role for DH IL-1β expression in heroin-conditioned suppression of a proinflammatory immune response.
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Affiliation(s)
- Jennifer L. Szczytkowski
- University of North Carolina at Chapel Hill, Department of Psychology, CB#3270, Chapel Hill, NC 27599-3270 USA
- Messiah College, Department of Psychology, One College Avenue Suite 3052, Mechanicsburg, PA 17055 USA
| | - Christina Lebonville
- University of North Carolina at Chapel Hill, Department of Psychology, CB#3270, Chapel Hill, NC 27599-3270 USA
| | - Lee Hutson
- University of North Carolina at Chapel Hill, Department of Psychology, CB#3270, Chapel Hill, NC 27599-3270 USA
| | - Rita A. Fuchs
- University of North Carolina at Chapel Hill, Department of Psychology, CB#3270, Chapel Hill, NC 27599-3270 USA
| | - Donald T. Lysle
- University of North Carolina at Chapel Hill, Department of Psychology, CB#3270, Chapel Hill, NC 27599-3270 USA
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Zhang J, Wang L, Xi L, Huang H, Hu Y, Li X, Huang X, Lu S, Sun J. Melanin in a meristematic mutant of Fonsecaea monophora inhibits the production of nitric oxide and Th1 cytokines of murine macrophages. Mycopathologia 2012; 175:515-22. [PMID: 23054330 DOI: 10.1007/s11046-012-9588-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2012] [Accepted: 09/21/2012] [Indexed: 11/24/2022]
Abstract
Melanin is a complex polymer which is secreted outside or constitutes the structure of fungal cell wall. It is considered as an important virulence factor in opportunistic pathogenic fungi. In this study, one albino mutant (CBS 125149) was generated from a parent meristematic mutant (CBS 122845) of Fonsecaea monophora. Transmission electron microscopy profiles showed that melanin in the parent strains appeared as electron-dense granules which located on the cell wall surface. We extracted the cell wall fractions from the two different strains by an alkali-acid method. The different strains or its cell wall fractions were interacted with the activated RAW264.7. The pigmented strain and its cell wall fraction could reduce the expression of inducible nitric oxide synthase gene and inhibit the synthesis of nitric oxide in vitro (P < 0.05). Exacerbated Th2 and inhibited Th1 response occurred in the interaction between activated RAW264.7 and the pigmented strain or its cell wall fraction. Collectively, our results suggest that melanin plays an important role in escaping the killing of oxidative burst in vitro. The exacerbated Th2 response probably accelerates the persistence of the fungus.
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Affiliation(s)
- Junmin Zhang
- Department of Dermatology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, 107 West Yanjiang Rd, Guangzhou, 510120, China.
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Garro AP, Chiapello LS, Baronetti JL, Masih DT. Eosinophils elicit proliferation of naive and fungal-specific cells in vivo so enhancing a T helper type 1 cytokine profile in favour of a protective immune response against Cryptococcus neoformans infection. Immunology 2011; 134:198-213. [PMID: 21896014 PMCID: PMC3194227 DOI: 10.1111/j.1365-2567.2011.03479.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2011] [Revised: 06/28/2011] [Accepted: 06/30/2011] [Indexed: 01/21/2023] Open
Abstract
Experimental Cryptococcus neoformans infection in rats has been shown to have similarities with human cryptococcosis, because as in healthy humans, rats can effectively contain cryptococcal infection. Moreover, it has been shown that eosinophils are components of the immune response to C. neoformans infections. In a previous in vitro study, we demonstrated that rat peritoneal eosinophils phagocytose opsonized live yeasts of C. neoformans, thereby triggering their activation, as indicated by the up-regulation of MHC and co-stimulatory molecules and the increase in interleukin-12, tumour necrosis factor-α and interferon-γ production. Furthermore, this work demonstrated that C. neoformans-specific CD4(+) and CD8(+) T lymphocytes cultured with these activated C. neoformans-pulsed eosinophils proliferated, and produced important amounts of T helper type 1 (Th1) cytokines in the absence of Th2 cytokine synthesis. In the present in vivo study, we have shown that C. neoformans-pulsed eosinophils are also able to migrate into lymphoid organs to present C. neoformans antigens, thereby priming naive and re-stimulating infected rats to induce T-cell and B-cell responses against infection with the fungus. Furthermore, the antigen-specific immune response induced by C. neoformans-pulsed eosinophils, which is characterized by the development of a Th1 microenvironment with increased levels of NO synthesis and C. neoformans-specific immunoglobulin production, was demonstrated to be able to protect rats against subsequent infection with fungus. In summary, the present work demonstrates that eosinophils act as antigen-presenting cells for the fungal antigen, hence initiating and modulating a C. neoformans-specific immune response. Finally, we suggest that C. neoformans-loaded eosinophils might participate in the protective immune response against these fungi.
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Affiliation(s)
- Ana P Garro
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), CONICET, Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Medina Allende y Haya de la Torre, Ciudad Universitaria, Córdoba, Argentina
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Baronetti JL, Chiapello LS, Garro AP, Masih DT. Treatment of rats with heat killed cells (HKC) of Cryptococcus neoformans var. grubii induces cellular activation in spleen and lymphatic nodes. Comp Immunol Microbiol Infect Dis 2011; 34:327-34. [DOI: 10.1016/j.cimid.2011.04.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2010] [Revised: 03/24/2011] [Accepted: 04/04/2011] [Indexed: 11/23/2022]
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13
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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14
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Lopes LCL, Rollin-Pinheiro R, Guimarães AJ, Bittencourt VCB, Martinez LR, Koba W, Farias SE, Nosanchuk JD, Barreto-Bergter E. Monoclonal antibodies against peptidorhamnomannans of Scedosporium apiospermum enhance the pathogenicity of the fungus. PLoS Negl Trop Dis 2010; 4:e853. [PMID: 20976055 PMCID: PMC2957425 DOI: 10.1371/journal.pntd.0000853] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2010] [Accepted: 09/22/2010] [Indexed: 11/19/2022] Open
Abstract
Scedosporium apiospermum is part of the Pseudallescheria-Scedosporium complex. Peptidorhamnomannans (PRMs) are cell wall glycopeptides present in some fungi, and their structures have been characterized in S. apiospermum, S. prolificans and Sporothrix schenckii. Prior work shows that PRMs can interact with host cells and that the glycopeptides are antigenic. In the present study, three monoclonal antibodies (mAbs, IgG1) to S. apiospermum derived PRM were generated and their effects on S. apiospermum were examined in vitro and in vivo. The mAbs recognized a carbohydrate epitope on PRM. In culture, addition of the PRM mAbs increased S. apiospermum conidia germination and reduced conidial phagocytosis by J774.16 macrophages. In a murine infection model, mice treated with antibodies to PRM died prior to control animals. Thus, PRM is involved in morphogenesis and the binding of this glycopeptide by mAbs enhanced the virulence of the fungus. Further insights into the effects of these glycopeptides on the pathobiology of S. apiospermum may lead to new avenues for preventing and treating scedosporiosis. The incidence of fungal infections has increased dramatically over the last 50 years, largely because of the increasing size of the population at risk, which especially includes immunocompromised hosts. Scedosporium apiospermum is a filamentous fungus that causes a variety of infections, ranging from localized disease to life-threatening disseminated infections. Glycoproteins are molecules present in the fungal surface and are comprised of carbohydrate and protein components. They are involved in different important functions in the fungal cell. Monoclonal antibodies can be used as therapeutic agents for infectious disease, but some factors involved in their efficacy are often not well understood. We found that monoclonal antibodies to glycoproteins present in fungal surface can be nonprotective and can even enhance the disease. The administration of these antibodies can affect functions of the fungal cell and the immune cells, resulting in a survival advantage for the fungus during interactions with the host.
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Affiliation(s)
- Livia C. L. Lopes
- Departments of Medicine and Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, United States of America
- Instituto de Microbiologia Professor Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Rodrigo Rollin-Pinheiro
- Instituto de Microbiologia Professor Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Allan J. Guimarães
- Departments of Medicine and Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Vera C. B. Bittencourt
- Departamento de Microbiologia e Parasitologia, Universidade Federal do Estado do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Luis R. Martinez
- Departments of Medicine and Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Wade Koba
- Gruss Magnetic Resonance Research Center, Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Sandra E. Farias
- Departamento de Fisiologia, Universidade Federal do Rio Grande do Sul, Rio Grande do Sul, Brazil
| | - Joshua D. Nosanchuk
- Departments of Medicine and Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Eliana Barreto-Bergter
- Instituto de Microbiologia Professor Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
- * E-mail:
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15
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Garro AP, Chiapello LS, Baronetti JL, Masih DT. Rat eosinophils stimulate the expansion of Cryptococcus neoformans-specific CD4(+) and CD8(+) T cells with a T-helper 1 profile. Immunology 2010; 132:174-87. [PMID: 21039463 DOI: 10.1111/j.1365-2567.2010.03351.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Experimental Cryptococcus neoformans infection in rats has been shown to have similarities with human cryptococcosis, revealing a strong granulomatous response and a low susceptibility to dissemination. Moreover, it has been shown that eosinophils are components of the inflammatory response to C. neoformans infections. In this in vitro study, we demonstrated that rat peritoneal eosinophils phagocytose opsonized live yeasts of C. neoformans, and that the phenomenon involves the engagement of FcγRII and CD18. Moreover, our results showed that the phagocytosis of opsonized C. neoformans triggers eosinophil activation, as indicated by (i) the up-regulation of major histocompatibility complex (MHC) class I, MHC class II and costimulatory molecules, and (ii) an increase in interleukin (IL)-12, tumour necrosis factor-α (TNF-α) and interferon-γ (IFN-γ) production. However, nitric oxide (NO) and hydrogen peroxide (H(2) O(2) ) synthesis by eosinophils was down-regulated after interaction with C. neoformans. Furthermore, this work demonstrated that CD4(+) and CD8(+) T lymphocytes isolated from spleens of infected rats and cultured with C. neoformans-pulsed eosinophils proliferate in an MHC class II- and class I-dependent manner, respectively, and produce important amounts of T-helper 1 (Th1) type cytokines, such as TNF-α and IFN-γ, in the absence of T-helper 2 (Th2) cytokine synthesis. In summary, the present study demonstrates that eosinophils act as fungal antigen-presenting cells and suggests that C. neoformans-loaded eosinophils might participate in the adaptive immune response.
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Affiliation(s)
- Ana P Garro
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), CONICET, Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Medina Allende y Haya de la Torre, Ciudad Universitaria, Córdoba, Argentina
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16
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Cunha MML, Franzen AJ, Seabra SH, Herbst MH, Vugman NV, Borba LP, de Souza W, Rozental S. Melanin in Fonsecaea pedrosoi: a trap for oxidative radicals. BMC Microbiol 2010; 10:80. [PMID: 20233438 PMCID: PMC2845570 DOI: 10.1186/1471-2180-10-80] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2009] [Accepted: 03/16/2010] [Indexed: 11/10/2022] Open
Abstract
Background The pathogenic fungus Fonsecaea pedrosoi constitutively produces the pigment melanin, an important virulence factor in fungi. Melanin is incorporated in the cell wall structure and provides chemical and physical protection for the fungus. We evaluated the production of nitric oxide (NO) in macrophages, the oxidative burst and the inducible nitric oxide synthase (i-NOS) activity in interactions between activated murine macrophages and F. pedrosoi. Experiments were carried out with or without tricyclazole (TC) treatment, a selective inhibitor of the dihydroxynaphthalene (DHN)-melanin biosynthesis pathway in F. pedrosoi. The paramagnetisms of melanin and the TC-melanin were analysed by electron spin resonance. The fungal growth responses to H2O2 and to S-nitroso-N-acetylpenicillamine (SNAP), a nitric oxide donor, were also evaluated. Results Melanised F. pedrosoi cells were more resistant to both H2O2 and NO. Nitrite was not detected in the supernatant of macrophages incubated with melanised fungal cells. However, i-NOS expression was unaffected by the presence of either untreated control F. pedrosoi or TC-treated F. pedrosoi. In addition, the inhibition of the DHN-melanin pathway by TC improved the oxidative burst capability of the macrophages. Conclusion The NO-trapping ability of F. pedrosoi melanin is an important mechanism to escape the oxidative burst of macrophages.
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Affiliation(s)
- Marcel M L Cunha
- Instituto de Biofísica Carlos Chagas Filho, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
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17
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Oliveira DL, Freire-de-Lima CG, Nosanchuk JD, Casadevall A, Rodrigues ML, Nimrichter L. Extracellular vesicles from Cryptococcus neoformans modulate macrophage functions. Infect Immun 2010; 78:1601-9. [PMID: 20145096 DOI: 10.1128/IAI.01171-09] [Citation(s) in RCA: 185] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Cryptococcus neoformans and distantly related fungal species release extracellular vesicles that traverse the cell wall and contain a varied assortment of components, some of which have been associated with virulence. Previous studies have suggested that these extracellular vesicles are produced in vitro and during animal infection, but the role of vesicular secretion during the interaction of fungi with host cells remains unknown. In this report, we demonstrate by fluorescence microscopy that mammalian macrophages can incorporate extracellular vesicles produced by C. neoformans. Incubation of cryptococcal vesicles with murine macrophages resulted in increased levels of extracellular tumor necrosis factor alpha (TNF-alpha), interleukin-10 (IL-10), and transforming growth factor beta (TGF-beta). Vesicle preparations also resulted in a dose-dependent stimulation of nitric oxide production by phagocytes, suggesting that vesicle components stimulate macrophages to produce antimicrobial compounds. Treated macrophages were more effective at killing C. neoformans yeast. Our results indicate that the extracellular vesicles of C. neoformans can stimulate macrophage function, apparently activating these phagocytic cells to enhance their antimicrobial activity. These results establish that cryptococcal vesicles are biologically active.
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Baronetti JL, Chiapello LS, Garro AP, Masih DT. Differential activation of peritoneal cells by subcutaneous treatment of rats with cryptococcal antigens. Clin Vaccine Immunol 2009; 16:1213-21. [PMID: 19494083 DOI: 10.1128/CVI.00100-09] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Previous studies in our laboratory have shown that the subcutaneous pretreatment of rats with heat-killed cells (HKC) of Cryptococcus neoformans emulsified in complete Freund adjuvant (CFA) promotes protective immunity against an intraperitoneal challenge with C. neoformans. In contrast, subcutaneous treatment with the capsular polysaccharide (PSC) emulsified in CFA exacerbates the cryptococcal infection. The purpose of this study was to analyze the mechanisms involved in these phenomena. Adherent peritoneal cells from rats treated with HKC-CFA showed upregulated ED2, CD80, and CD86 expression; an increase in the level of production of anticryptococcal metabolites; and the enhanced production of interleukin-12 (IL-12) in comparison with the findings for cells from rats treated with CFA-phosphate-buffered saline (PBS). Adherent peritoneal cells from rats treated with PSC-CFA, however, also presented upregulated ED2, CD80, and CD86 expression compared to the level of expression for peritoneal cells from controls, but these cells showed an increase in arginase activity and decreased levels of production of IL-12 and tumor necrosis factor (TNF) compared with the activity and levels of production by peritoneal cells from CFA-PBS-treated rats. In addition, treatment with HKC-CFA resulted in a rise in the phagocytic and anticryptococcal activities of adherent peritoneal cells compared to those for control rats. However, adherent peritoneal cells from rats treated with PSC-CFA presented a reduction in anticryptococcal activity in comparison with that for cells from animals treated with CFA-PBS. These results show the differential activation between adherent peritoneal cells from HKC-CFA- and PSC-CFA-treated rats, with this differential activation at the primary site of infection possibly being responsible, at least in part, for the phenomena of protection and exacerbation observed in our model.
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19
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Chiapello LS, Baronetti JL, Garro AP, Spesso MF, Masih DT. Cryptococcus neoformans glucuronoxylomannan induces macrophage apoptosis mediated by nitric oxide in a caspase-independent pathway. Int Immunol 2008; 20:1527-41. [DOI: 10.1093/intimm/dxn112] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
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20
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Szczytkowski JL, Lysle DT. Conditioned effects of heroin on the expression of inducible nitric oxide synthase in the rat are susceptible to extinction and latent inhibition. Psychopharmacology (Berl) 2007; 191:879-89. [PMID: 17211650 DOI: 10.1007/s00213-006-0673-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2006] [Accepted: 12/09/2006] [Indexed: 10/23/2022]
Abstract
RATIONALE The administration of heroin has been shown to inhibit the induction of nitric oxide, a molecule known to play a critical role in immune function. Previous research has shown that this alteration can be conditioned to environmental stimuli that have been associated with drug administration. However, it remains unknown whether the conditioned effects of heroin on nitric oxide formation follow accepted principles of learning. OBJECTIVE This study sought to determine whether manipulations that induce extinction and latent inhibition, two learning paradigms known to reduce the expression of conditioned responses, would alter heroin's conditioned effects on the expression of inducible nitric oxide synthase (iNOS). MATERIALS AND METHODS The conditioning procedure involved repeated pairing of heroin administration with placement into a standard conditioning chamber. Rats were repeatedly exposed to the chambers without heroin reinforcement to determine whether the conditioned response would extinguish. To induce latent inhibition, rats received repeated exposure to the chamber before the start of conditioning to inhibit the acquisition of the conditioned response. Ten days after the final conditioning session, all rats were injected with lipopolysaccharide (LPS) to induce iNOS expression. Spleen and liver tissue were removed to determine iNOS expression using reverse transcriptase polymerase chain reaction. Blood was collected to determine the concentration of nitrite/nitrate. RESULTS The results showed that both extinction and latent inhibition reduced the conditioned effects of heroin on the production of nitric oxide. CONCLUSION This study provides the first evidence that the conditioned effects of heroin on nitric oxide production follow accepted principles of learning.
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Affiliation(s)
- Jennifer L Szczytkowski
- Department of Psychology and Curriculum in Neurobiology, CB#3270, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-3270, USA
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21
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Serradell MC, Guasconi L, Cervi L, Chiapello LS, Masih DT. Excretory-secretory products from Fasciola hepatica induce eosinophil apoptosis by a caspase-dependent mechanism. Vet Immunol Immunopathol 2007; 117:197-208. [PMID: 17449115 DOI: 10.1016/j.vetimm.2007.03.007] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2006] [Revised: 02/12/2007] [Accepted: 03/07/2007] [Indexed: 11/27/2022]
Abstract
Eosinophils (Eo) are known to be important effector cells in the host defense against helminth parasites. Excretory-secretory products (ESP) released by helminths have shown wide immunomodulatory properties, such as the induction of cellular apoptosis. We investigated the ability of ESP from Fasciola hepatica to induce Eo apoptosis. In this work, we observed that ESP induced an early apoptosis of rat peritoneal eosinophils and that this phenomenon was time- and concentration-dependent. Furthermore, we demonstrated that activation of protein tyrosine kinases (TyrK) and caspases were necessary to mediate the Eo apoptosis induced by the ESP, and that carbohydrate components present in these antigens were involved in this effect. We have described for the first time the ability of ESP from F. hepatica to modify the viability of Eo by apoptosis induction. Besides that, we have observed Eo apoptosis in the liver of rats 21 days after F. hepatica infection. The diminution in Eo survival in early infection could be a parasite strategy in order to prevent a host immune response.
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Affiliation(s)
- Marianela C Serradell
- Parasitología, Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, CIBICI-CONICET, Medina Allende y Haya de la Torre, Ciudad Universitaria, 5000 Cordoba, Argentina
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22
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Zhou Q, Murphy WJ. Immune response and immunotherapy to Cryptococcus infections. Immunol Res 2007; 35:191-208. [PMID: 17172646 DOI: 10.1385/ir:35:3:191] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/1999] [Revised: 11/30/1999] [Accepted: 11/30/1999] [Indexed: 11/11/2022]
Abstract
Cryptococcus neoformans is a ubiquitous fungus that can cause lifethreatening infections during immunosuppressive states such as acquired immunodeficiency syndrome (AIDS) and after bone marrow transplantation (BMT). Infected individuals normally succumb to meningitis and meningoencephalitis caused by dissemination of C. neoformans to the brain. In this review, we analyze the current understanding of the interaction between host immune response and C. neoformans as well as the current state of immunotherapeutic strategies for treating cryptococcosis.
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Affiliation(s)
- Qing Zhou
- Department of Microbiology and Immunology, University of Nevada, Reno, NV 89557, USA
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Baronetti JL, Chiapello LS, Aoki MP, Gea S, Masih DT. Heat killed cells of Cryptococcus neoformans var. grubii induces protective immunity in rats: immunological and histopathological parameters. Med Mycol 2006; 44:493-504. [PMID: 16966166 DOI: 10.1080/13693780600750022] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
Abstract
Different clinical parameters which included cell-mediated immune (CMI) response, were evaluated in a model of disseminated cryptococcosis in rats. The experimental animals were pretreated four days prior to their exposure to Cryptococcus neoformans var. grubii with either heat killed cells of this yeastlike pathogen (HKC) or capsular polysaccharide (CPS) emulsified in complete Freund adjuvant (CFA). Rats treated with HKC-CFA and intraperitoneally infected with C. neoformans var. grubii had significantly better clearance of yeasts from tissues, a lower concentration of the cryptococcal capsular polysaccharide, glucuronoxylomannan (GXM), in serum and tissues, and better histopathological parameters compared to unpretreated infected rats. In contrast, rats treated with CPS-CFA presented an exacerbation of infection with a significantly higher fungal burden in tissues, a higher concentration of GXM in serum, and worse histopathological parameters compared to similar unpretreated infected rats. In addition, HKC-CFA treatment produced a T helper 1 (Th1) profile with improvements in the spleen cell proliferative response, in the level of INFgamma production by CD4 T cells, and in the nitric oxide (NO) production by peritoneal cells. On the other hand, rats treated with CPS-CFA showed an increased level of the immunoregulatory cytokine IL10 production by CD4 T cells, but no modification in the NO production by peritoneal cells.
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Affiliation(s)
- José L Baronetti
- Micología, Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
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Abstract
We studied the ability of glucuronoxylomannan (GXM), the major constituent of Cryptococcus neoformans capsular polysaccharide, to induce apoptosis in lymphocytes from normal rats. Spleen mononuclear cells (Smc) from normal rats treated with GXM for 24 h exhibited, in comparison with controls, an increased hypodiploidy in the DNA profile after staining with propidium iodide, as well as increased ladder-type DNA fragmentation in agarose gel electrophoresis and a high number of positive cells in the terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling (TUNEL) reaction. Furthermore, increased hypodiploidy in the DNA profile was also observed in Smc expressing T-cell receptor (TCR +). We also studied the induction of apoptosis in lungs and spleens from rats in the immunosuppressor period of disseminated cryptococcosis. TUNEL labeling of lungs and spleens from rats obtained 14 days after infection with C. neoformans showed a large number of apoptotic cells. Our results provide strong cytometric, molecular and morphological evidence that apoptosis could be a previously unrecognized immunosuppressive property of GXM in vitro. This programmed cell death may be involved in the immunosuppression observed during C. neoformans infection.
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Affiliation(s)
- L S Chiapello
- Micología, Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
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25
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Cox GM, Harrison TS, McDade HC, Taborda CP, Heinrich G, Casadevall A, Perfect JR. Superoxide dismutase influences the virulence of Cryptococcus neoformans by affecting growth within macrophages. Infect Immun 2003; 71:173-80. [PMID: 12496163 PMCID: PMC143417 DOI: 10.1128/iai.71.1.173-180.2003] [Citation(s) in RCA: 191] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Superoxide dismutase (SOD) is an enzyme that converts superoxide radicals into hydrogen peroxide and molecular oxygen and has been shown to contribute to the virulence of many human-pathogenic bacteria through its ability to neutralize toxic levels of reactive oxygen species generated by the host. SOD has also been speculated to be important in the pathogenesis of fungal infections, but the role of this enzyme has not been rigorously investigated. To examine the contribution of SOD to the pathogenesis of fungal infections, we cloned the Cu,Zn SOD-encoding gene (SOD1) from the human-pathogenic yeast Cryptococcus neoformans and made mutants via targeted disruption. The sod1 mutant strains had marked decreases in SOD activity and were strikingly more susceptible to reactive oxygen species in vitro. A sod1 mutant was significantly less virulent than the wild-type strain and two independent reconstituted strains, as measured by cumulative survival in the mouse inhalational model. In vitro studies established that the sod1 strain had attenuated growth compared to the growth of the wild type and a reconstituted strain inside macrophages producing reduced amounts of nitric oxide. These findings demonstrate that (i) the Cu,Zn SOD contributes to virulence but is not required for pathogenicity in C. neoformans; (ii) the decreased virulence of the sod1 strain may be due to increased susceptibility to oxygen radicals within macrophages; and (iii) other antioxidant defense systems in C. neoformans can compensate for the loss of the Cu,Zn SOD in vivo.
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Affiliation(s)
- Gary M Cox
- Department of Medicine and Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina, USA.
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26
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Rivera J, Mukherjee J, Weiss LM, Casadevall A. Antibody efficacy in murine pulmonary Cryptococcus neoformans infection: a role for nitric oxide. J Immunol 2002; 168:3419-27. [PMID: 11907100 DOI: 10.4049/jimmunol.168.7.3419] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We investigated the pathogenesis of pulmonary Cryptococcus neoformans infection and passive Ab efficacy in mice deficient in inducible NO synthase (NOS2(-/-)) and the parental strain. Parental mice lived significantly longer than NOS2(-/-) mice after intratracheal infection, despite having a higher lung fungal burden. Administration of Ab reduced lung CFU in both NOS2(-/-) and parental mice, but prolonged survival and increased the inflammatory response only in parental mice. Ab administration was associated with increased serum nitrite and reduced polysaccharide levels in parental mice. Eosinophils were present in greater numbers in the lung of infected NOS2(-/-) mice than parental mice, irrespective of Ab administration. C. neoformans infection in NOS2(-/-) mice resulted in significantly higher levels of IFN-gamma, monocyte chemoattractant protein-1, and macrophage-inflammatory protein-1alpha than parental mice. Ab administration had different effects on infected NOS2(-/-) and parental mice with respect to IFN-gamma, monocoyte chemoattractant protein-1, and macrophage-inflammatory protein-1alpha levels. Ab administration increased lung levels of IFN-gamma in parental mice and reduced levels in NOS2(-/-) mice. The results indicate that NO is involved in the regulation of cytokine expression in response to cryptococcal pneumonia and is necessary for Ab efficacy against C. neoformans in mice. Our findings indicate a complex relationship between Ab efficacy against C. neoformans and cytokine expression, underscoring the interdependency of cellular and humoral defense mechanisms.
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MESH Headings
- Animals
- Antibodies, Fungal/administration & dosage
- Antibodies, Fungal/physiology
- Antibodies, Fungal/therapeutic use
- Antigens, Fungal/blood
- Antigens, Fungal/immunology
- Antigens, Fungal/metabolism
- Cell Movement/genetics
- Cell Movement/immunology
- Cryptococcosis/genetics
- Cryptococcosis/immunology
- Cryptococcosis/metabolism
- Cryptococcosis/pathology
- Cryptococcus neoformans/growth & development
- Cryptococcus neoformans/immunology
- Female
- Injections, Intraperitoneal
- Leukocyte Count
- Lung/pathology
- Lung Diseases, Fungal/genetics
- Lung Diseases, Fungal/immunology
- Lung Diseases, Fungal/metabolism
- Lung Diseases, Fungal/pathology
- Macrophages, Alveolar/immunology
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- Mice, Knockout
- Nitric Oxide/physiology
- Nitric Oxide Synthase/deficiency
- Nitric Oxide Synthase/genetics
- Nitric Oxide Synthase Type II
- Nitrites/blood
- Phagocytosis/genetics
- Polysaccharides/blood
- Polysaccharides/immunology
- Polysaccharides/pharmacokinetics
- Survival Analysis
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Affiliation(s)
- Johanna Rivera
- Department of Microbiology and Immunology and University of Massachusetts Medical School, Worcester, MA 01605, USA
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Chiapello L, Iribarren P, Cervi L, Rubinstein H, Masih DT. Mechanisms for induction of immunosuppression during experimental cryptococcosis: role of glucuronoxylomannan. Clin Immunol 2001; 100:96-106. [PMID: 11414750 DOI: 10.1006/clim.2001.5046] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In previous work we have demonstrated that spleen mononuclear (Spm) cells from rats obtained 14 days after infection with Cryptococcus neoformans showed a diminution in proliferative response to Concanavalin A (Con A). In this study we further investigate some characteristics of the Spm cell population involved in the immunosuppressor phenomenon induced by C. neoformans. We observed that unstimulated Spm cells expressing T-cell receptor (TCR+) from infected rats were reduced in number after 96 h of culture. When the Spm cells from infected rats were stimulated with Con A, increased production of IL-10, reduced levels of IL-2, and decreased CD11a surface expression were shown. These immunosuppressor phenomena were also observed when the capsular polysaccharide, glucuronoxylomannan (GXM), was added to cultures of Spm cells from normal rats. However, GXM had a more pronounced effect in reducing the number of cells surviving in culture than that observed during infection and produced an increase in IL-4 production by Con-A-stimulated Spm cells. Addition of anti-IL-10 monoclonal antibody to cultures restored the lymphoproliferation of Spm cells from infected animals, indicating that IL-10 production is a suppressor mechanism of cell-mediated immunity during experimental infection. The results presented here indicate that at least two mechanisms mediate the nonspecific suppression in this model of cryptococcosis: IL-10 production and diminution of the number of T cells. GXM could be involved, since it has a pronounced effect in the reduction of Spm cells in vitro.
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Affiliation(s)
- L Chiapello
- Micología, Universidad Nacional de Córdoba, Córdoba, 5000, Argentina
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Abstract
A factor VIII-deficient knockout mouse was used as a model for severe hemophilia A to characterize the immune response to recombinant human factor VIII (fVIII) and to study new approaches for induction of immune tolerance to fVIII. Mice initially received periodic injections of fVIII in doses similar to those used for the treatment of human hemophilia A. To induce immune tolerance, a hamster monoclonal antibody specific for murine CD40 ligand (CD40L or CD154) was injected with fVIII. Control mice received fVIII alone or fVIII and hamster immunoglobulin G. After treatment, humoral and cellular immune responses were evaluated. Ninety-five percent of anti-CD40L-treated mice had lower titers of anti-fVIII antibody (less than 1 microg/mL) compared with fVIII-injected control mice (mean, 18 microg/mL). To determine whether anti-CD40L treatment induces long-term immune tolerance, mice were rechallenged 3 times with fVIII alone. At 150 days after treatment, 12 of 22 anti-CD40L-treated mice remained tolerant to fVIII (anti-fVIII antibody titers less than 1 microg/mL). However, tolerant mice immunized with tetanus toxoid (TT) developed high anti-TT antibody, demonstrating that tolerance is fVIII specific. T cells from tolerant mice showed impaired proliferative responses after stimulation with fVIII in vitro and lack of production of the cytokines interleukin-2 (IL-2), IL-4, interferon gamma, and IL-10. These results demonstrate that long-term immune tolerance to fVIII was effectively induced after early blockade of CD40-CD40L interaction. In addition, the lack of tolerance in this model was associated with the expression of a Th2 phenotype.
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Affiliation(s)
- G Rossi
- Department of Immunology, Holland Laboratory, American Red Cross, Rockville, MD 20855, USA
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Rodriguez-Galán MC, Correa SG, Cejas H, Sotomayor CE. Impaired activity of phagocytic cells in Candida albicans infection after exposure to chronic varied stress. Neuroimmunomodulation 2001; 9:193-202. [PMID: 11847481 DOI: 10.1159/000049026] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVE Candidiasis is a prototypic opportunistic fungal disease that may follow severe modulations of the immune system of the host. The purpose of this study was to evaluate which innate immune mechanisms involved in the protection against fungal invasion are impaired under stress conditions. METHODS Wistar rats were infected intraperitoneally with Candida albicans and immediately exposed to chronic varied stress (CVS) over 10 days (CVS; Ca-S); the fungal burden (CFU), histopathological lesion and ACTH levels were evaluated. Additionally, functional assessment of peritoneal cells (PC) included the phagocytic and anticandidacidal activities and the production of H(2)O(2) and NO. RESULTS In the only infected animals (Ca), C. albicans colonization stimulated an efficient inflammatory response, while in Ca-S rats poor tissue reactions were associated with increased CFU in livers and kidneys (p < 0.05, Ca vs. Ca-S). Whereas the phagocytic process was not modified, the candidacidal activity of PC was significantly decreased after the application of CVS (p < 0.001, Ca vs. Ca-S). The H(2)O(2) production by macrophages and neutrophils was downregulated by the infection, and while at early intervals these cells possessed a residual oxidative capacity, by day 10, the production of this metabolite was blocked. Spontaneous NO production by macrophages was significantly increased in both Ca and Ca-S animals (p < 0.001), but in stressed rats, this reactive nitrogen intermediate was noticeably downregulated (p < 0.05, Ca vs. Ca-S). The hyperactivity of hypothalamus-pituitary-adrenal axis after exposure to stress was confirmed by an increase in baseline plasma ACTH levels. CONCLUSION These results show that during infection with C. albicans, the exposure to CVS contributes to the spread of the fungus and downregulates critical functions of phagocytic cells involved in the control of this opportunistic pathogen.
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Affiliation(s)
- M C Rodriguez-Galán
- Inmunología, Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Argentina
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