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Sobrevilla-Hernández G, Franco-Molina MA, Zárate-Triviño DG, Kawas JR, Hernández-Martínez SP, García-Coronado PL, Santana-Krímskaya SE, Alvizo-Báez CA, Rodríguez-Padilla C. Development of a new generation of miniemulsion based on cottonseed oil with α-tocopherol and ZnO and evaluation of its adjuvant activity. PeerJ 2023; 11:e14981. [PMID: 36968001 PMCID: PMC10035431 DOI: 10.7717/peerj.14981] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Accepted: 02/09/2023] [Indexed: 03/29/2023] Open
Abstract
Background Emulsions have been widely used as immunological adjuvants. But the use of materials derived from plants such as cottonseed oil, alpha-tocopherol, or minerals such as zinc, as well as their use at the nanometric scale has been little explored. In this study, we develop a new miniemulsion and evaluated its antioxidant and phagocytic capacity, as well as parameters related to immune response stimulation by cytokine expression and antibodies production in a mice model. Methods Formulated CN (cottonseed oil miniemulsion) and CNZ (cottonseed oil miniemulsion whit zinc oxide nanoparticles) miniemulsions were characterized by scanning electronic microscopy SEM, DLS and FT-IR. In murine macrophages, splenocytes and thymocytes primary cultures safety and cytotoxicity were determined by MTT. In macrophages the antioxidant and phagocytic capacity was evaluated. In BALB/c mice, the stimulation of the immune system was determined by the expression of cytokines and the production of antibodies. Results The CN and CNZ presented stability for 90 days. Immediately after preparation, the CN presented a higher particle size (543.1 nm) than CNZ (320 nm). FT-IR demonstrated the correct nanoparticle synthesis by the absence of sulfate groups. CN and CNZ (1.25 to 10 µL/mL) had no toxic effect on macrophages (p = 0.108), splenocytes (p = 0.413), and thymocytes (p = 0.923). All CN and CNZ doses tested induced nitric oxide and antioxidants production in dose dependent manner when compared with control. CN-ovalbumin and CNZ-ovalbumin treatments in femoral subcutaneous tissue area showed inflammation with higher leukocyte infiltration compared with FCA. The intraperitoneal administration with CN, CNZ, and FCA showed a higher total intraperitoneal cells recruitment (CD14+) after 24 h of inoculation than control (p = 0.0001). CN and CNZ increased the phagocyte capacity with respect to untreated macrophages in the Candida albicans-phagocytosis assay. The evaluation of residual CFU indicated that only CN significantly decreased (p = 0.004) this value at 3 h. By other side, only CN increased (p = 0.002) the nitric oxide production. CNZ stimulated a major INFγ secretion compared with FCA at day 7. A major IL-2 secretion was observed at days 7 and 14, stimulated with CN and CNZ. Both miniemulsions did not affect the antibody isotypes production (IgG1, IgG2a, IgG3, IgA and IgM) at days 7, 14, 28, and 42. CN induced a significant IgG production against OVA, but lesser than FCA. Conclusions The two new miniemulsions with adjuvant and antioxidant capacity, were capable of generating leukocyte infiltration and increased cytokines and antibodies production.
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Affiliation(s)
- Gustavo Sobrevilla-Hernández
- Laboratorio de Inmunología y Virología, Facultad de Ciencias Biológicas, Universidad Autónoma de Nuevo León, San Nicolás de los Garza, Nuevo León, Mexico
| | - Moisés Armides Franco-Molina
- Laboratorio de Inmunología y Virología, Facultad de Ciencias Biológicas, Universidad Autónoma de Nuevo León, San Nicolás de los Garza, Nuevo León, Mexico
| | - Diana G. Zárate-Triviño
- Laboratorio de Inmunología y Virología, Facultad de Ciencias Biológicas, Universidad Autónoma de Nuevo León, San Nicolás de los Garza, Nuevo León, Mexico
| | - Jorge R. Kawas
- Posgrado Conjunto Agronomía-Veterinaría, Universidad Autónoma de Nuevo León, General Escobedo, Nuevo León, Mexico
| | | | - Paola Leonor García-Coronado
- Laboratorio de Inmunología y Virología, Facultad de Ciencias Biológicas, Universidad Autónoma de Nuevo León, San Nicolás de los Garza, Nuevo León, Mexico
| | - Silvia Elena Santana-Krímskaya
- Laboratorio de Inmunología y Virología, Facultad de Ciencias Biológicas, Universidad Autónoma de Nuevo León, San Nicolás de los Garza, Nuevo León, Mexico
| | - Cynthia Aracely Alvizo-Báez
- Laboratorio de Inmunología y Virología, Facultad de Ciencias Biológicas, Universidad Autónoma de Nuevo León, San Nicolás de los Garza, Nuevo León, Mexico
| | - Cristina Rodríguez-Padilla
- Laboratorio de Inmunología y Virología, Facultad de Ciencias Biológicas, Universidad Autónoma de Nuevo León, San Nicolás de los Garza, Nuevo León, Mexico
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Qin Z, Bouteau A, Herbst C, Igyártó BZ. Pre-exposure to mRNA-LNP inhibits adaptive immune responses and alters innate immune fitness in an inheritable fashion. PLoS Pathog 2022; 18:e1010830. [PMID: 36054264 PMCID: PMC9477420 DOI: 10.1371/journal.ppat.1010830] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Revised: 09/15/2022] [Accepted: 08/22/2022] [Indexed: 11/18/2022] Open
Abstract
Hundreds of millions of SARS-CoV-2 mRNA-LNP vaccine doses have already been administered to humans. However, we lack a comprehensive understanding of the immune effects of this platform. The mRNA-LNP-based SARS-CoV-2 vaccine is highly inflammatory, and its synthetic ionizable lipid component responsible for the induction of inflammation has a long in vivo half-life. Since chronic inflammation can lead to immune exhaustion and non-responsiveness, we sought to determine the effects of pre-exposure to the mRNA-LNP on adaptive immune responses and innate immune fitness. We found that pre-exposure to mRNA-LNPs or LNP alone led to long-term inhibition of the adaptive immune response, which could be overcome using standard adjuvants. On the other hand, we report that after pre-exposure to mRNA-LNPs, the resistance of mice to heterologous infections with influenza virus increased while resistance to Candida albicans decreased. The diminished resistance to Candida albicans correlated with a general decrease in blood neutrophil percentages. Interestingly, mice pre-exposed to the mRNA-LNP platform can pass down the acquired immune traits to their offspring, providing better protection against influenza. In summary, the mRNA-LNP vaccine platform induces long-term unexpected immunological changes affecting both adaptive immune responses and heterologous protection against infections. Thus, our studies highlight the need for more research to determine this platform's true impact on human health.
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Affiliation(s)
- Zhen Qin
- Department of Microbiology and Immunology, Thomas Jefferson University, Philadelphia, Pennsylvania, United States of America
| | - Aurélie Bouteau
- Department of Microbiology and Immunology, Thomas Jefferson University, Philadelphia, Pennsylvania, United States of America
| | - Christopher Herbst
- Department of Microbiology and Immunology, Thomas Jefferson University, Philadelphia, Pennsylvania, United States of America
| | - Botond Z. Igyártó
- Department of Microbiology and Immunology, Thomas Jefferson University, Philadelphia, Pennsylvania, United States of America
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3
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Sanches RCO, Mambelli F, Oliveira SC. Neutrophils and schistosomiasis: a missing piece in pathology. Parasite Immunol 2022; 44:e12916. [PMID: 35332932 DOI: 10.1111/pim.12916] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Revised: 03/10/2022] [Accepted: 03/18/2022] [Indexed: 12/01/2022]
Abstract
Schistosomiasis is a chronic human parasitic disease that causes serious health problems worldwide. The disease-associated liver pathology is one of the hallmarks of infections by S. mansoni and S. japonicum, and is accountable for the debilitating condition found in infected patients. In the past few years, investigative studies have highlighted the key role played by neutrophils and the influence of inflammasome signaling pathway in different pathological conditions. However, it is noteworthy that the study of inflammasome activation in neutrophils has been overlooked by reports concerning macrophages and monocytes. This interplay between neutrophils and inflammasomes is much more poorly investigated during schistosomiasis. Herein we reviewed the role of neutrophils during schistosomiasis and addressed the potential connection between these cells and inflammasome activation in this context.
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Affiliation(s)
- Rodrigo C O Sanches
- Departamento de Bioquímica e Imunologia, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Fábio Mambelli
- Departamento de Bioquímica e Imunologia, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Sergio C Oliveira
- Departamento de Bioquímica e Imunologia, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.,Instituto Nacional de Ciência e Tecnologia em Doenças Tropicais (INCT-DT), CNPq MCT, Salvador, Brazil
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4
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Qin Z, Bouteau A, Herbst C, Igyártó BZ. Pre-exposure to mRNA-LNP inhibits adaptive immune responses and alters innate immune fitness in an inheritable fashion.. [PMID: 36032972 PMCID: PMC9413714 DOI: 10.1101/2022.03.16.484616] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Hundreds of millions of SARS-CoV-2 mRNA-LNP vaccine doses have already been administered to humans. However, we lack a comprehensive understanding of the immune effects of this platform. The mRNA-LNP-based SARS-CoV-2 vaccine is highly inflammatory, and its synthetic ionizable lipid component responsible for the induction of inflammation has a long in vivo half-life. Since chronic inflammation can lead to immune exhaustion and non-responsiveness, we sought to determine the effects of pre-exposure to the mRNA-LNP on adaptive immune responses and innate immune fitness. We found that pre-exposure to mRNA-LNPs or LNP alone led to long-term inhibition of the adaptive immune responses, which could be overcome using standard adjuvants. On the other hand, we report that after pre-exposure to mRNA-LNPs, the resistance of mice to heterologous infections with influenza virus increased while Candida albicans decreased. The diminished resistance to Candida albicans correlated with a general decrease in blood neutrophil percentages. Interestingly, mice pre-exposed to the mRNA-LNP platform can pass down the acquired immune traits to their offspring, providing better protection against influenza. In summary, the mRNA-LNP vaccine platform induces long-term unexpected immunological changes affecting both adaptive immune responses and heterologous protection against infections. Thus, our studies highlight the need for more research to determine this platform’s true impact on human health. We bring experimental evidence that pre-exposure to mRNA-LNPs or its LNP component affects innate and adaptive immune responses. Pre-exposure to mRNA-LNPs led to long-term inhibition of the adaptive immune responses, which the use of adjuvants could overcome. On the other hand, we report that after pre-exposure to mRNA-LNPs, the resistance of mice to heterologous infections with influenza virus increased while Candida albicans decreased. We also detected a general neutropenia in the mRNA-LNP exposed mice. Interestingly, mice pre-exposed to mRNA-LNPs can pass down the acquired immune traits to their offspring. In summary, the mRNA-LNP vaccine platform induces long-term immunological changes that can affect both adaptive immune responses and heterologous protection against infections, some of which can be inherited by the offspring. More studies are needed to understand the mechanisms responsible for these effects and determine this platform’s impact on human health.
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5
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Ricci E, Roselletti E, Gentili M, Sabbatini S, Perito S, Riccardi C, Migliorati G, Monari C, Ronchetti S. Glucocorticoid-Induced Leucine Zipper-Mediated TLR2 Downregulation Accounts for Reduced Neutrophil Activity Following Acute DEX Treatment. Cells 2021; 10:2228. [PMID: 34571877 PMCID: PMC8472062 DOI: 10.3390/cells10092228] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 08/25/2021] [Accepted: 08/25/2021] [Indexed: 12/03/2022] Open
Abstract
Glucocorticoids are the most powerful anti-inflammatory and immunosuppressive pharmacological drugs available, despite their adverse effects. Glucocorticoid-induced leucine zipper (GILZ) is a glucocorticoid-induced gene that shares several anti-inflammatory properties with glucocorticoids. Although immunosuppressive effects of glucocorticoids on neutrophils remain poorly understood, we previously demonstrated that GILZ suppresses neutrophil activation under glucocorticoid treatment. Here, we sought to explore the regulation of Toll-like receptor 2 (TLR2) by the synthetic glucocorticoid dexamethasone (DEX) on neutrophils and the associated GILZ involvement. Peripheral blood neutrophils were isolated from wild type and GILZ-knock-out (KO) mice. TLR2 was found to be downregulated by the in vivo administration of glucocorticoids in wild type but not in GILZ-KO neutrophils, suggesting the involvement of GILZ in TLR2 downregulation. Accordingly, the TLR2-associated anti-fungal activity of neutrophils was reduced by DEX treatment in wild type but not GILZ-KO neutrophils. Furthermore, GILZ did not interact with NF-κB but was found to bind with STAT5, a pivotal factor in the regulation of TLR2 expression. A similar modulation of TLR2 expression, impaired phagocytosis, and killing activity was observed in circulating human neutrophils treated in vitro with DEX. These results demonstrate that glucocorticoids reduce the ability of neutrophils to respond to infections by downregulating TLR2 via GILZ, thereby reducing critical functions.
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Affiliation(s)
- Erika Ricci
- Department of Medicine and Surgery, Pharmacology Division, University of Perugia, 06132 Perugia, Italy; (E.R.); (M.G.); (C.R.); (G.M.)
| | - Elena Roselletti
- Department of Medicine and Surgery, Medical Microbiology Division, University of Perugia, 06132 Perugia, Italy; (E.R.); (S.S.); (S.P.); (C.M.)
| | - Marco Gentili
- Department of Medicine and Surgery, Pharmacology Division, University of Perugia, 06132 Perugia, Italy; (E.R.); (M.G.); (C.R.); (G.M.)
| | - Samuele Sabbatini
- Department of Medicine and Surgery, Medical Microbiology Division, University of Perugia, 06132 Perugia, Italy; (E.R.); (S.S.); (S.P.); (C.M.)
| | - Stefano Perito
- Department of Medicine and Surgery, Medical Microbiology Division, University of Perugia, 06132 Perugia, Italy; (E.R.); (S.S.); (S.P.); (C.M.)
| | - Carlo Riccardi
- Department of Medicine and Surgery, Pharmacology Division, University of Perugia, 06132 Perugia, Italy; (E.R.); (M.G.); (C.R.); (G.M.)
| | - Graziella Migliorati
- Department of Medicine and Surgery, Pharmacology Division, University of Perugia, 06132 Perugia, Italy; (E.R.); (M.G.); (C.R.); (G.M.)
| | - Claudia Monari
- Department of Medicine and Surgery, Medical Microbiology Division, University of Perugia, 06132 Perugia, Italy; (E.R.); (S.S.); (S.P.); (C.M.)
| | - Simona Ronchetti
- Department of Medicine and Surgery, Pharmacology Division, University of Perugia, 06132 Perugia, Italy; (E.R.); (M.G.); (C.R.); (G.M.)
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6
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Wei LQ, Tan JC, Wang Y, Mei YK, Xue JY, Tian L, Song KY, Han L, Cui YC, Peng YB, Li JQ, Liu NN, Wang H. Fingolimod Potentiates the Antifungal Activity of Amphotericin B. Front Cell Infect Microbiol 2021; 11:627917. [PMID: 33968796 PMCID: PMC8102868 DOI: 10.3389/fcimb.2021.627917] [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: 11/19/2020] [Accepted: 04/09/2021] [Indexed: 12/30/2022] Open
Abstract
Candida albicans (C. albicans) is an opportunistic human fungal pathogen that can cause severe infection in clinic. Its incidence and mortality rate has been increasing rapidly. Amphotericin B (AMB), the clinical golden standard antifungal agent, has severe side effects that limit its clinical application. Thus, lowering the concentration and increasing the efficacy of AMB in a combinatorial antifungal therapy have been pursued by both industry and academia. Here we identify that fingolimod (FTY720), an immunomodulatory drug used for oral treatment of relapsing-remitting multiple sclerosis, can potentiate the efficacy of AMB against C. albicans growth synergistically. Furthermore, we observe an antifungal efficacy of FTY720 in combination with AMB against diverse fungal pathogens. Intriguingly, cells treated with both drugs are hypersensitive to endothelial endocytosis and macrophage killing. This is later found to be due to the hyperaccumulation of reactive oxygen species and the corresponding increase in activities of superoxide dismutase and catalase in the cells that received combinatorial treatment. Therefore, the combination of AMB and FTY720 provides a promising antifungal strategy.
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Affiliation(s)
- Lu-Qi Wei
- State Key Laboratory of Oncogenes and Related Genes, Center for Single-Cell Omics, School of Public Health, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jing-Cong Tan
- State Key Laboratory of Oncogenes and Related Genes, Center for Single-Cell Omics, School of Public Health, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yue Wang
- State Key Laboratory of Oncogenes and Related Genes, Center for Single-Cell Omics, School of Public Health, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yi-Kun Mei
- State Key Laboratory of Oncogenes and Related Genes, Center for Single-Cell Omics, School of Public Health, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jia-Yu Xue
- State Key Laboratory of Oncogenes and Related Genes, Center for Single-Cell Omics, School of Public Health, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Lei Tian
- State Key Laboratory of Oncogenes and Related Genes, Center for Single-Cell Omics, School of Public Health, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Ke-Yu Song
- State Key Laboratory of Oncogenes and Related Genes, Center for Single-Cell Omics, School of Public Health, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Lu Han
- State Key Laboratory of Oncogenes and Related Genes, Center for Single-Cell Omics, School of Public Health, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Ying-Chao Cui
- Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yi-Bing Peng
- Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.,Faculty of Medical Laboratory Science, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jing-Quan Li
- State Key Laboratory of Oncogenes and Related Genes, Center for Single-Cell Omics, School of Public Health, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Ning-Ning Liu
- State Key Laboratory of Oncogenes and Related Genes, Center for Single-Cell Omics, School of Public Health, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Hui Wang
- State Key Laboratory of Oncogenes and Related Genes, Center for Single-Cell Omics, School of Public Health, Shanghai Jiao Tong University School of Medicine, Shanghai, China
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Glutamate dehydrogenase (Gdh2)-dependent alkalization is dispensable for escape from macrophages and virulence of Candida albicans. PLoS Pathog 2020; 16:e1008328. [PMID: 32936835 PMCID: PMC7521896 DOI: 10.1371/journal.ppat.1008328] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 09/28/2020] [Accepted: 08/14/2020] [Indexed: 11/19/2022] Open
Abstract
Candida albicans cells depend on the energy derived from amino acid catabolism to induce and sustain hyphal growth inside phagosomes of engulfing macrophages. The concomitant deamination of amino acids is thought to neutralize the acidic microenvironment of phagosomes, a presumed requisite for survival and initiation of hyphal growth. Here, in contrast to an existing model, we show that mitochondrial-localized NAD+-dependent glutamate dehydrogenase (GDH2) catalyzing the deamination of glutamate to α-ketoglutarate, and not the cytosolic urea amidolyase (DUR1,2), accounts for the observed alkalization of media when amino acids are the sole sources of carbon and nitrogen. C. albicans strains lacking GDH2 (gdh2-/-) are viable and do not extrude ammonia on amino acid-based media. Environmental alkalization does not occur under conditions of high glucose (2%), a finding attributable to glucose-repression of GDH2 expression and mitochondrial function. Consistently, inhibition of oxidative phosphorylation or mitochondrial translation by antimycin A or chloramphenicol, respectively, prevents alkalization. GDH2 expression and mitochondrial function are derepressed as glucose levels are lowered from 2% (~110 mM) to 0.2% (~11 mM), or when glycerol is used as primary carbon source. Using time-lapse microscopy, we document that gdh2-/- cells survive, filament and escape from primary murine macrophages at rates indistinguishable from wildtype. In intact hosts, such as in fly and murine models of systemic candidiasis, gdh2-/- mutants are as virulent as wildtype. Thus, although Gdh2 has a critical role in central nitrogen metabolism, Gdh2-catalyzed deamination of glutamate is surprisingly dispensable for escape from macrophages and virulence. Consistently, using the pH-sensitive dye (pHrodo), we observed no significant difference between wildtype and gdh2-/- mutants in phagosomal pH modulation. Following engulfment of fungal cells, the phagosomal compartment is rapidly acidified and hyphal growth initiates and sustained under consistently acidic conditions within phagosomes. Together, our results demonstrate that amino acid-dependent alkalization is not essential for hyphal growth, survival in macrophages and hosts. An accurate understanding of the microenvironment within macrophage phagosomes and the metabolic events underlying the survival of phagocytized C. albicans cells and their escape are critical to understanding the host-pathogen interactions that ultimately determine the pathogenic outcome. Candida albicans is a commensal component of the human microflora and the most common fungal pathogen. The incidence of candidiasis is low in healthy populations. Consequently, environmental factors, such as interactions with innate immune cells, play critical roles. Macrophages provide the first line of defense and rapidly internalize C. albicans cells within specialized intracellular compartments called phagosomes. The microenvironment within phagosomes is dynamic and ill defined, but has a low pH, and contains potent hydrolytic enzymes and oxidative stressors. Despite the inhospitable conditions, phagocytized C. albicans cells catabolize amino acids to obtain energy to survive and grow. Here, we have critically examined amino acid catabolism and ammonia extrusion in C. albicans, the latter is thought to neutralize the phagosomal pH and induce the switch of morphologies from round “yeast-like” to elongated hyphal cells that can pierce the phagosomal membrane leading to escape from macrophages. We report that Gdh2, which catalyzes the deamination of glutamate to α-ketoglutarate, is responsible for the observed environmental alkalization when C. albicans catabolize amino acids in vitro. However, the phagosomes formed as macrophages engulf wildtype or gdh2-/- cells rapidly become acidified, indicating that Gdh2 has no apparent role in modulating phagosomal pH. Strikingly, and similar to wildtype cells, gdh2-/- cells initiate and sustain hyphal growth enabling them to escape from macrophages. Also, Gdh2 is dispensable for virulent growth in systemic models of infection. These results provide new insights into host-pathogen interactions that determine the pathogenic outcome of C. albicans infections.
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Díaz-Godínez C, Carrero JC. The state of art of neutrophil extracellular traps in protozoan and helminthic infections. Biosci Rep 2019; 39:BSR20180916. [PMID: 30498092 PMCID: PMC6328873 DOI: 10.1042/bsr20180916] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Revised: 10/26/2018] [Accepted: 11/15/2018] [Indexed: 12/23/2022] Open
Abstract
Neutrophil extracellular traps (NETs) are DNA fibers associated with histones, enzymes from neutrophil granules and anti-microbial peptides. NETs are released in a process denominated NETosis, which involves sequential steps that culminate with the DNA extrusion. NETosis has been described as a new mechanism of innate immunity related to defense against different pathogens. The initial studies of NETs were carried out with bacteria and fungi, but currently a large variety of microorganisms capable of inducing NETs have been described including protozoan and helminth parasites. Nevertheless, we have little knowledge about how NETosis process is carried out in response to the parasites, and about its implication in the resolution of this kind of disease. In the best case, the NETs entrap and kill parasites in vitro, but in others, immobilize the parasites without affecting their viability. Moreover, insufficient studies on the NETs in animal models of infections that would help to define their role, and the association of NETs with chronic inflammatory pathologies such as those occurring in several parasitic infections have left open the possibility of NETs contributing to pathology instead of protection. In this review, we focus on the reported mechanisms that lead to NET release by protozoan and helminth parasites and the evidence that support the role of NETosis in the resolution or pathogenesis of parasitic diseases.
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Affiliation(s)
- César Díaz-Godínez
- Department of Immunology, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, 04510, México D.F., México
| | - Julio C Carrero
- Department of Immunology, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, 04510, México D.F., México
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Candida albicans Ras1 Inactivation Increases Resistance to Phagosomal Killing by Human Neutrophils. Infect Immun 2018; 86:IAI.00685-18. [PMID: 30249746 DOI: 10.1128/iai.00685-18] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 09/20/2018] [Indexed: 12/18/2022] Open
Abstract
Host phagocytic cells are crucial players in initial defense against Candida albicans infection. C. albicans utilizes MAP kinases and Ras1 stress response signaling pathways to protect itself from killing by immune cells. In this study, we tested the importance of these pathways in C. albicans phagocytosis by neutrophils and subsequent phagosomal survival. Phagocytosis was influenced by C. albicans morphology, so hyphal length of >10 μm reduced the phagocytic index (PI) 2- to 3-fold in human neutrophils. Primary human neutrophils killed 81% of phagocytosed C. albicans, while primary mouse neutrophils killed 63% of yeasts. We found that both the C. albicans Cek1 and Hog1 pathways were required for survival of phagocytosed yeast, whereas deletion of C. albicans RAS1 resulted in an 84% increase in survival within neutrophils compared to that of the wild type (WT). The absence of Ras1 did not alter reactive oxygen species (ROS) production by C. albicans; however, phagocytosed C. albicans Δ/Δras1 cells reduced ROS release by neutrophils by 86%. Moreover, C. albicans Δ/Δras1 cells had increased resistance to hydrogen peroxide as a result of high levels of catalase activity. This phenotype was specific to Ras1, since these effects were not observed in the absence of its partner Cyr1 or with its downstream target Efg1. In addition, C. albicans Δ/Δras1 cells had a significantly increased resistance to nonoxidative killing by human neutrophil peptide 1 (HNP-1) that was reversed by restoring cellular cAMP levels. These data show that C. albicans Ras1 inactivation leads to fungal resistance to both oxidative and nonoxidative mechanisms of neutrophil phagosomal killing.
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10
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Surawut S, Makjaroen J, Thim-Uam A, Wongphoom J, Palaga T, Pisitkun P, Chindamporn A, Leelahavanichkul A. Increased susceptibility against Cryptococcus neoformans of lupus mouse models (pristane-induction and FcGRIIb deficiency) is associated with activated macrophage, regardless of genetic background. J Microbiol 2018; 57:45-53. [PMID: 30456753 DOI: 10.1007/s12275-019-8311-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 08/17/2018] [Accepted: 09/06/2018] [Indexed: 12/16/2022]
Abstract
The severity of cryptococcosis in lupus from varying genetic-backgrounds might be different due to the heterogeneity of lupus-pathogenesis. This study explored cryptococcosis in lupus mouse models of pristane-induction (normal genetic-background) and FcGRIIb deficiency (genetic defect). Because the severity of lupus nephritis, as determined by proteinuria and serum creatinine, between pristane and FcGRIIb-/- mice were similar at 6-month-old, Cryptococcus neoformans was intravenously administered in 6-month-old mice and were age-matched with wild-type. Indeed, the cryptococcosis disease severity, as evaluated by mortality rate, internal-organ fungal burdens and serum cytokines, between pristane and FcGRIIb-/- mice was not different. However, the severity of cryptococcosis in wild-type was less severe than the lupus mice. On the other hand, phagocytosis activity of peritoneal macrophages from lupus mice (pristane and FcGRIIb-/-) was more predominant than the wild-type without the difference in macrophage killing-activity among these groups. In addition, the number of active T helper cells (Th-cell) in the spleen, including Th-cells with intracellular IFN-γ, from lupus mice (pristane and FcGRIIb-/-) was higher than wildtype. Moreover, these active Th-cells were even higher after 2 weeks of cryptococcal infection. These data support enhanced macrophage activation through prominent Th-cells in both lupus models. In conclusion, an increased susceptibility of cryptococcosis in both lupus models was independent to genetic background. This might due to Th-cell enhanced macrophage phagocytosis with the interference of macrophage killing activity from Cryptococcal immune-evasion properties.
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Affiliation(s)
- Saowapha Surawut
- Medical Microbiology, Interdisciplinary Program, Graduate School, Chulalongkorn University, Bangkok, Thailand
| | - Jiradej Makjaroen
- Medical Microbiology, Interdisciplinary Program, Graduate School, Chulalongkorn University, Bangkok, Thailand
| | - Arthid Thim-Uam
- Inter-Department Program of Biomedical Sciences, Faculty of Graduate, Chulalongkorn University, Bangkok, Thailand
| | - Jutamas Wongphoom
- Division of Pathology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Tanapat Palaga
- Department of Microbiology, Faculty of Science, Chulalongkorn University, Bangkok, Thailand
| | - Prapaporn Pisitkun
- Division of Allergy, Immunology and Rheumatology, Department of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
| | - Ariya Chindamporn
- Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Asada Leelahavanichkul
- Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand. .,Skeletal Disorders Research Unit, Faculty of Dentistry, Chulalongkorn University, Bangkok, Thailand.
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Guo Y, Chang Q, Cheng L, Xiong S, Jia X, Lin X, Zhao X. C-Type Lectin Receptor CD23 Is Required for Host Defense against Candida albicans and Aspergillus fumigatus Infection. THE JOURNAL OF IMMUNOLOGY 2018; 201:2427-2440. [DOI: 10.4049/jimmunol.1800620] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 08/06/2018] [Indexed: 12/27/2022]
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12
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Gastrointestinal Colonization of Candida Albicans Increases Serum (1→3)-β-D-Glucan, without Candidemia, and Worsens Cecal Ligation and Puncture Sepsis in Murine Model. Shock 2018; 49:62-70. [PMID: 28498297 DOI: 10.1097/shk.0000000000000896] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The role of intestinal Candida albicans in bacterial sepsis, in the absence of candidemia, was investigated in murine models. Live C albicans or normal saline solution (NSS) was administered orally once, followed by 5 days of daily oral antibiotic-mixtures (ATB). Cecal ligation and puncture (CLP) was then performed to induce sepsis.Fecal Candida was detected by culture only in models with Candida administration. Oral Candida administration with/without ATB enhanced gut-pathogenic bacteria as determined by microbiome analysis. Despite negative candidemia, serum (1→3)-β-D-glucan (BG) was higher in CLP with Candida preconditioning models than in CLP-controls (NSS-preconditioning) at 6 and/or 18 h post-CLP. Blood bacterial burdens were not increased with Candida administration.Additionally, CLP with high-dose Candida (10 colony forming units) induced higher levels of fecal Candida, serum BG, serum IL-6, and mortality than the lowest dose (100 colony forming units). Interestingly, fluconazole attenuated fecal Candida and improved survival in mice with live-Candida administration, but not in the CLP-controls. Heat-killed Candida preparations or their supernatants reduced bone marrow-derived macrophage killing activity in vitro but enhanced cytokine production.In conclusion, intestinal abundance of fungi and/or fungal-molecules was associated with increased bacterial sepsis severity, perhaps through cytokine storm induction and/or decreased macrophage killing activity. These observations suggest that further investigation of the potential role of intestinal fungal burdens in sepsis is warranted.
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Alsina-Beauchamp D, Escós A, Fajardo P, González-Romero D, Díaz-Mora E, Risco A, Martín-Serrano MA, Del Fresno C, Dominguez-Andrés J, Aparicio N, Zur R, Shpiro N, Brown GD, Ardavín C, Netea MG, Alemany S, Sanz-Ezquerro JJ, Cuenda A. Myeloid cell deficiency of p38γ/p38δ protects against candidiasis and regulates antifungal immunity. EMBO Mol Med 2018; 10:e8485. [PMID: 29661910 PMCID: PMC5938613 DOI: 10.15252/emmm.201708485] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Revised: 03/12/2018] [Accepted: 03/19/2018] [Indexed: 12/27/2022] Open
Abstract
Candida albicans is a frequent aetiologic agent of sepsis associated with high mortality in immunocompromised patients. Developing new antifungal therapies is a medical need due to the low efficiency and resistance to current antifungal drugs. Here, we show that p38γ and p38δ regulate the innate immune response to C. albicans We describe a new TAK1-TPL2-MKK1-ERK1/2 pathway in macrophages, which is activated by Dectin-1 engagement and positively regulated by p38γ/p38δ. In mice, p38γ/p38δ deficiency protects against C. albicans infection by increasing ROS and iNOS production and thus the antifungal capacity of neutrophils and macrophages, and by decreasing the hyper-inflammation that leads to severe host damage. Leucocyte recruitment to infected kidneys and production of inflammatory mediators are decreased in p38γ/δ-null mice, reducing septic shock. p38γ/p38δ in myeloid cells are critical for this effect. Moreover, pharmacological inhibition of p38γ/p38δ in mice reduces fungal burden, revealing that these p38MAPKs may be therapeutic targets for treating C. albicans infection in humans.
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Affiliation(s)
| | - Alejandra Escós
- Department of Immunology and Oncology, Centro Nacional de Biotecnología/CSIC, Madrid, Spain
| | - Pilar Fajardo
- Department of Immunology and Oncology, Centro Nacional de Biotecnología/CSIC, Madrid, Spain
| | - Diego González-Romero
- Department of Immunology and Oncology, Centro Nacional de Biotecnología/CSIC, Madrid, Spain
| | - Ester Díaz-Mora
- Department of Immunology and Oncology, Centro Nacional de Biotecnología/CSIC, Madrid, Spain
| | - Ana Risco
- Department of Immunology and Oncology, Centro Nacional de Biotecnología/CSIC, Madrid, Spain
| | | | - Carlos Del Fresno
- Immunobiology of Inflammation Laboratory Centro Nacional de Investigaciones Cardiovasculares Carlos III, Madrid, Spain
| | - Jorge Dominguez-Andrés
- Department of Immunology and Oncology, Centro Nacional de Biotecnología/CSIC, Madrid, Spain
| | - Noelia Aparicio
- Department of Immunology and Oncology, Centro Nacional de Biotecnología/CSIC, Madrid, Spain
| | - Rafal Zur
- Department of Immunology and Oncology, Centro Nacional de Biotecnología/CSIC, Madrid, Spain
| | - Natalia Shpiro
- Medical Research Council Protein Phosphorylation Unit, Sir James Black Building, School of Life Sciences, University of Dundee, Dundee, UK
| | - Gordon D Brown
- Aberdeen Fungal Group, Institute of Medical Sciences, Medical Research Council Centre for Medical Mycology at the University of Aberdeen, Aberdeen, UK
| | - Carlos Ardavín
- Department of Immunology and Oncology, Centro Nacional de Biotecnología/CSIC, Madrid, Spain
| | - Mihai G Netea
- Department of Internal Medicine and Radboud Center for Infectious Diseases, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - Susana Alemany
- Instituto de Investigaciones Biomédicas Alberto Sols, CSIC-UAM, Madrid, Spain
| | | | - Ana Cuenda
- Department of Immunology and Oncology, Centro Nacional de Biotecnología/CSIC, Madrid, Spain
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Fc Gamma Receptor IIB Deficient Mice: A Lupus Model with Increased Endotoxin Tolerance-Related Sepsis Susceptibility. Shock 2018; 47:743-752. [PMID: 27849678 DOI: 10.1097/shk.0000000000000796] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Hyper-elevated immune response of FcGRIIb-/- mice, a lupus model with an inhibitory-signaling defect, can become exhausted (less subsequent immune-response than the first response) with sequential lipopolysaccharide (LPS) stimulation. Endotoxin tolerance-related modifications of inflammatory response were investigated in FcGRIIb-/- mice in both an in vivo sepsis model and in vitro using cultured macrophages. Serum cytokine concentrations, after the second LPS injection (at 5-fold higher levels than the first dose), did not exceed the first dose levels in either FcGRIIb-/- or wild-type mice. These data indicated an endotoxin-tolerance response in both genetic backgrounds. However, the difference of cytokine levels between the first and second LPS injection was more prominent in FcGRIIb-/- mice. More importantly, CLP-induced sepsis after LPS-preconditioning (two separated doses of LPS administration) was more severe in FcGRIIb-/- mice (as measured by mortality rate, bacteria count in blood, serum cytokines, creatinine, and alanine transaminase). An attenuated response was demonstrated after two sequential LPS stimulations of bone-marrow-derived macrophages. Cytokine production was reduced and lower bacterial killing activity occurred with macrophages from FcGRIIb-/- mice relative to wild-type macrophages. Thus, there is a more prominent effect of endotoxin-tolerance in FcGRIIb-/- macrophages relative to wild-type. In conclusion, repeated-LPS administrations induced quantitatively greater endotoxin-tolerance responses in FcGRIIb-/- mice both in vivo and in vitro. Endotoxin-tolerance in vivo was associated with more severe sepsis, at least in part, due to macrophage-dysfunction.
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15
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JNK1 negatively controls antifungal innate immunity by suppressing CD23 expression. Nat Med 2017; 23:337-346. [PMID: 28112734 PMCID: PMC5592785 DOI: 10.1038/nm.4260] [Citation(s) in RCA: 76] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Accepted: 12/06/2016] [Indexed: 12/13/2022]
Abstract
Opportunistic fungal infections are a leading cause of death among immune-compromised patients, and there is a pressing need to develop new antifungal therapeutic agents because of toxicity and resistance to the antifungal drugs currently in use. Although C-type lectin receptor- and Toll-like receptor-induced signaling pathways are key activators of host antifungal immunity, little is known about the mechanisms that negatively regulate host immune responses to a fungal infection. Here we found that JNK1 activation suppresses antifungal immunity in mice. We showed that JNK1-deficient mice had a significantly higher survival rate than wild-type control mice in response to Candida albicans infection, and the expression of JNK1 in hematopoietic innate immune cells was critical for this effect. JNK1 deficiency leads to significantly higher induction of CD23, a novel C-type lectin receptor, through NFATc1-mediated regulation of the CD23 gene promoter. Blocking either CD23 upregulation or CD23-dependent nitric oxide production eliminated the enhanced antifungal response found in JNK1-deficient mice. Notably, JNK inhibitors exerted potent antifungal therapeutic effects in both mouse and human cells infected with C. albicans, indicating that JNK1 may be a therapeutic target for treating fungal infection.
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16
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Surawut S, Ondee T, Taratummarat S, Palaga T, Pisitkun P, Chindamporn A, Leelahavanichkul A. The role of macrophages in the susceptibility of Fc gamma receptor IIb deficient mice to Cryptococcus neoformans. Sci Rep 2017; 7:40006. [PMID: 28074867 PMCID: PMC5225418 DOI: 10.1038/srep40006] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Accepted: 11/30/2016] [Indexed: 02/04/2023] Open
Abstract
Dysfunctional polymorphisms of FcγRIIb, an inhibitory receptor, are associated with Systemic Lupus Erythaematosus (SLE). Cryptococcosis is an invasive fungal infection in SLE, perhaps due to the de novo immune defect. We investigated cryptococcosis in the FcγRIIb-/- mouse-lupus-model. Mortality, after intravenous C. neoformans-induced cryptococcosis, in young (8-week-old) and older (24-week-old) FcγRIIb-/- mice, was higher than in age-matched wild-types. Severe cryptococcosis in the FcγRIIb-/- mice was demonstrated by high fungal burdens in the internal organs with histological cryptococcoma-like lesions and high levels of TNF-α and IL-6, but not IL-10. Interestingly, FcγRIIb-/- macrophages demonstrated more prominent phagocytosis but did not differ in killing activity in vitro and the striking TNF-α, IL-6 and IL-10 levels, compared to wild-type cells. Indeed, in vivo macrophage depletion with liposomal clodronate attenuated the fungal burdens in FcγRIIb-/- mice, but not wild-type mice. When administered to wild-type mice, FcγRIIb-/- macrophages with phagocytosed Cryptococcus resulted in higher fungal burdens than FcγRIIb+/+ macrophages with phagocytosed Cryptococcus. These results support, at least in part, a model whereby, in FcγRIIb-/- mice, enhanced C. neoformans transmigration occurs through infected macrophages. In summary, prominent phagocytosis, with limited effective killing activity, and high pro-inflammatory cytokine production by FcγRIIb-/- macrophages were correlated with more severe cryptococcosis in FcγRIIb-/- mice.
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Affiliation(s)
- Saowapha Surawut
- Medical Microbiology, Interdisciplinary Program, Graduate School, Chulalongkorn University, Bangkok, Thailand
| | - Thunnicha Ondee
- Medical Sciences Program, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Sujittra Taratummarat
- Medical Microbiology, Interdisciplinary Program, Graduate School, Chulalongkorn University, Bangkok, Thailand
| | - Tanapat Palaga
- Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
- Department of Microbiology, Faculty of Science, Chulalongkorn University, Bangkok, Thailand
| | - Prapaporn Pisitkun
- Division of Allergy, Immunology, and Rheumatology, Department of Medicine, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
| | - Ariya Chindamporn
- Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Asada Leelahavanichkul
- Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
- Center of Excellence in Immunology and Immune-mediated Diseases, Department of Microbiology, Faculty of Medicine, Bangkok, Thailand
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17
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Ventolini G. Progresses in vaginal microflora physiology and implications for bacterial vaginosis and candidiasis. ACTA ACUST UNITED AC 2016; 12:283-91. [PMID: 27215488 DOI: 10.2217/whe.16.5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- Gary Ventolini
- School of Medicine at Texas Tech. University Health Sciences Center, 800 W 4th Street, Odessa, TX 79763, USA
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18
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Masking of β(1-3)-glucan in the cell wall of Candida albicans from detection by innate immune cells depends on phosphatidylserine. Infect Immun 2014; 82:4405-13. [PMID: 25114110 DOI: 10.1128/iai.01612-14] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The virulence of Candida albicans in a mouse model of invasive candidiasis is dependent on the phospholipids phosphatidylserine (PS) and phosphatidylethanolamine (PE). Disruption of the PS synthase gene CHO1 (i.e., cho1Δ/Δ) eliminates PS and blocks the de novo pathway for PE biosynthesis. In addition, the cho1Δ/Δ mutant's ability to cause invasive disease is severely compromised. The cho1Δ/Δ mutant also exhibits cell wall defects, and in this study, it was determined that loss of PS results in decreased masking of cell wall β(1-3)-glucan from the immune system. In wild-type C. albicans, the outer mannan layer of the wall masks the inner layer of β(1-3)-glucan from exposure and detection by innate immune effector molecules like the C-type signaling lectin Dectin-1, which is found on macrophages, neutrophils, and dendritic cells. The cho1Δ/Δ mutant exhibits increases in exposure of β(1-3)-glucan, which leads to greater binding by Dectin-1 in both yeast and hyphal forms. The unmasking of β(1-3)-glucan also results in increased elicitation of TNF-α from macrophages in a Dectin-1-dependent manner. The role of phospholipids in fungal pathogenesis is an emerging field, and this is the first study showing that loss of PS in C. albicans results in decreased masking of β(1-3)-glucan, which may contribute to our understanding of fungus-host interactions.
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19
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Smeekens SP, Malireddi RK, Plantinga TS, Buffen K, Oosting M, Joosten LAB, Kullberg BJ, Perfect JR, Scott WK, van de Veerdonk FL, Xavier RJ, van de Vosse E, Kanneganti TD, Johnson MD, Netea MG. Autophagy is redundant for the host defense against systemic Candida albicans infections. Eur J Clin Microbiol Infect Dis 2013; 33:711-22. [PMID: 24202731 DOI: 10.1007/s10096-013-2002-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2013] [Accepted: 10/16/2013] [Indexed: 12/16/2022]
Abstract
Autophagy has been demonstrated to play an important role in the immunity against intracellular pathogens, but very little is known about its role in the host defense against fungal pathogens such as Candida albicans. Therefore, the role of autophagy for the host defense against C. albicans was assessed by complementary approaches using mice defective in autophagy, as well as immunological and genetic studies in humans. Although C. albicans induced LC3-II formation in macrophages, myeloid cell-specific ATG7(-/-) mice with defects in autophagy did not display an increased susceptibility to disseminated candidiasis. In in vitro experiments in human blood mononuclear cells, blocking autophagy modulated cytokine production induced by lipopolysaccharide, but not by C. albicans. Furthermore, autophagy modulation in human monocytes did not influence the phagocytosis and killing of C. albicans. Finally, 18 single-nucleotide polymorphisms in 13 autophagy genes were not associated with susceptibility to candidemia or clinical outcome of disease in a large cohort of patients, and there was no correlation between these genetic variants and cytokine production in either candidemia patients or healthy controls. Based on these complementary in vitro and in vivo studies, it can be concluded that autophagy is redundant for the host response against systemic infections with C. albicans.
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Affiliation(s)
- S P Smeekens
- Department of Medicine, Radboud university medical center, Geert Grooteplein Zuid 8, 6525 GA, Nijmegen, The Netherlands
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20
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Marranzino G, Villena J, Salva S, Alvarez S. Stimulation of macrophages by immunobiotic Lactobacillus strains: influence beyond the intestinal tract. Microbiol Immunol 2013; 56:771-81. [PMID: 22846065 DOI: 10.1111/j.1348-0421.2012.00495.x] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Lactobacillus rhamnosus CRL1505 (Lr1505), L. rhamnosus CRL1506 (Lr1506) and L. casei CRL431 (Lc431) are able to stimulate intestinal immunity, but only Lr1505 and Lc431 are able to stimulate immunity in the respiratory tract. With the aim of advancing the understanding of the immunological mechanisms involved in stimulation of distant mucosal sites, this study evaluated the effects of orally administered probiotics on the functions of alveolar and peritoneal macrophages. Compared to a control group, these three lactobacilli were able to significantly increase phagocytic and microbicidal activities of peritoneal macrophages. After intraperitoneal challenge with pathogenic Candida albicans, mice treated with immunobiotics had significantly lower pathogen counts in infected organs. Moreover, lactobacilli-treated mice had a stronger immune response against C. albicans. On the other hand, only Lc1505 and Lc431 were able to improve activity of and cytokine production by alveolar macrophages. Only in these two groups was there better resistance to respiratory challenge with C. albicans, which correlated with improved respiratory immune response. The results of this study suggest that consumption of some probiotic strains could be useful for improving resistance to infections in sites distant from the gut by increasing the activity of macrophages at those sites.
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Affiliation(s)
- Gabriela Marranzino
- Laboratory of Clinical and Experimental Biochemistry, Reference Center for Lactobacilli, Tucuman, Argentina
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21
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Martino RF, Davicino RC, Mattar MA, Sasso CV, Casali YA, Alonso R, Anesini C, Correa SG, Micalizzi B. Macrophages activation by a purified fraction, free of nordihydroguaiaretic acid (NDGA), fromLarrea divaricataCav. as a potential novel therapy againstCandida albicans. Immunopharmacol Immunotoxicol 2012; 34:975-82. [DOI: 10.3109/08923973.2012.682225] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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22
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Vonk AG, Netea MG, Kullberg BJ. Phagocytosis and intracellular killing of Candida albicans by murine polymorphonuclear neutrophils. Methods Mol Biol 2012; 845:277-287. [PMID: 22328381 DOI: 10.1007/978-1-61779-539-8_18] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Polymorphonuclear neutrophils (PMNs) are important phagocytes in the control of Candida infections. The phagocytic contribution of PMNs to host defence can by assessed by various methods, such as microbiological assays. However, assessment and definition of intracellular killing capacity can be a source of considerable confusion. A comparison of the growth of Candida in the presence of PMN with the growth of Candida in phagocyte-free suspensions may lead to an overestimation of killing capacity because PMNs can use both intracellular and extracellular killing mechanisms. Here, we describe the use of an adherent monolayer of exudate peritoneal PMNs that is used to differentiate between the process of phagocytosis and intracellular killing.
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Affiliation(s)
- Alieke G Vonk
- Department of Medical Microbiology and Infectious Diseases, University Medical Center Rotterdam, Rotterdam, The Netherlands.
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23
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Smeekens SP, van de Veerdonk FL, Joosten LAB, Jacobs L, Jansen T, Williams DL, van der Meer JWM, Kullberg BJ, Netea MG. The classical CD14⁺⁺ CD16⁻ monocytes, but not the patrolling CD14⁺ CD16⁺ monocytes, promote Th17 responses to Candida albicans. Eur J Immunol 2011; 41:2915-24. [PMID: 21695694 DOI: 10.1002/eji.201141418] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2011] [Revised: 05/30/2011] [Accepted: 06/17/2011] [Indexed: 01/09/2023]
Abstract
In the present study, we investigated the functional differences between cluster of differentiation (CD)14(++) CD16(-) and CD14(+) CD16(+) monocytes during anti-Candida host defense. CD14(++) CD16(-) are the "classical" monocytes and represent the majority of circulating monocytes in humans, while CD14(+) CD16(+) monocytes patrol the vasculature for maintenance of tissue integrity and repair. Both monocyte subsets inhibited the germination of live Candida albicans, and there was no difference in their capacity to phagocytose and kill Candida. Although production of IL-6 and IL-10 induced by C. albicans was found to be similar between monocyte subsets, IL-1β and prostaglandin E2 (PGE2) production was higher in CD14(++) CD16(-) compared with CD14(+) CD16(+) monocytes. In line with the increased production of IL-1β and PGE2, central mediators for inducing Th17 responses, CD14(++) CD16(-) monocytes induced greater Th17 responses upon stimulation with heat-killed C. albicans yeast. The percentage of cells that expressed mannose receptor (MR) was higher in the CD14(++) CD16(-) monocyte subset, and MR-specific stimulation induced higher Th17 responses only in co-cultures of CD14(++) CD16(-) monocytes and CD4 lymphocytes. In conclusion, both monocyte subsets have potent innate antifungal properties, but only CD14(++) CD16(-) monocytes are capable of inducing a potent Th17 response to C. albicans, an important component of antifungal host defense.
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Affiliation(s)
- Sanne P Smeekens
- Department of Medicine, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
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Saunus JM, Wagner SA, Matias MA, Hu Y, Zaini ZM, Farah CS. Early activation of the interleukin-23-17 axis in a murine model of oropharyngeal candidiasis. Mol Oral Microbiol 2011; 25:343-56. [PMID: 20883223 DOI: 10.1111/j.2041-1014.2010.00570.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Candida albicans is an oral commensal yeast that causes oropharyngeal candidiasis (OPC) in immunocompromised individuals. The immunological pathways involved in OPC have been revisited after the interleukin-17 (IL-17) pathway was implicated in fungal immunity. We studied immediate (<24 h) and adaptive (3-6 day) IL-12 and IL-23-17 pathway activation in naive p40(-/-) mice, which lack IL-12 and IL-23 and develop severe, chronic OPC upon oral inoculation with C. albicans. Macrophages from p40(-/-) mice were less efficient than C57BL/6J controls at killing C. albicans in vitro but very low numbers in the oral mucosae of infected C57BL/6J mice suggest that they are not critical in vivo, at least in this strain. Migration of macrophages to regional lymph nodes of infected p40(-/-) mice was impaired; however, dendritic cell migration was not affected. Recombinant IL-12 therapy provided only temporary relief from OPC, suggesting that IL-23 is required for full protection. In C57BL/6J mice, but not p40(-/-) mice, messenger RNAs encoding IL-23p19 and IL-17 were induced in the oral mucosa within 24 h of infection (6 ± 0.6 and 12 ± 2.7-fold). By day 6 of infection in C57BL/6J mice, IL-17A messenger RNA level had increased 5.1 ± 1.8 and 83 ± 21-fold in regional lymph nodes and oral tissues respectively. Ablation of p40 was associated with delayed or abrogated induction of IL-17A pathway targets (monocyte chemoattractant protein-1, IL-6 and macrophage inflammatory protein-2), and a lack of organized recruitment of neutrophils to the infected oral mucosa. Overall our data show that the IL-23-17A axis is activated early in the oral mucosae of immunologically naive mice with OPC.
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Affiliation(s)
- J M Saunus
- School of Dentistry, the University of Queensland, Brisbane, Australia
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25
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Differential effects of IL-17 pathway in disseminated candidiasis and zymosan-induced multiple organ failure. Shock 2010; 34:407-11. [PMID: 20160669 DOI: 10.1097/shk.0b013e3181d67041] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
The role of the IL-17 pathway in antifungal host defense is controversial. Several studies suggested that IL-17 is crucial for the protection against Candida infection, whereas other studies reported that IL-17 may contribute to inflammatory pathology and worsening of fungal disease. To address these discrepancies, we assessed the differential role of IL-17 pathway in two models of fungal sepsis: intravenous infection with live Candida albicans, in which fungal growth is the main cause of mortality, and zymosan-induced multiple organ failure, in which the inflammatory pathology drives the mortality. First, IL-17 receptor-deficient (IL-17RA) mice showed increased mortality and higher fungal loads in the kidneys in the model of disseminated candidiasis, partly caused by lower neutrophil recruitment in the IL-17RA mice. Second, IL-17RA mice were not protected against the multiorgan failure induced by zymosan. These data demonstrate that IL-17 does not have a major contribution to the inflammatory pathology leading to organ failure in fungal sepsis and support the concept that the IL-17 pathway is protective in antifungal host defense.
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26
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Linden JR, Maccani MA, Laforce-Nesbitt SS, Bliss JM. High efficiency opsonin-independent phagocytosis of Candida parapsilosis by human neutrophils. Med Mycol 2010; 48:355-64. [PMID: 19672781 DOI: 10.1080/13693780903164566] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Candida species are associated with invasive fungal infections, and C. parapsilosis has become increasingly prevalent. As key antifungal effector cells, the function of human neutrophils confronting C. parapsilosis was investigated. We hypothesized that interaction between neutrophils and Candida species may not be uniform. Opsonins were omitted from these studies to understand the antifungal mechanisms at their most basic level. Human neutrophils underwent phagocytosis of C. parapsilosis with much higher efficiency than with C. albicans. Immunofluorescence assays with ss-glucan specific antibody detected more surface exposed ss-glucan on C. parapsilosis than C. albicans. However, blockade of the ss-glucan receptor Dectin-1, reduced phagocytosis of C. albicans but not C. parapsilosis. Inclusion of excess beta-glucan, mannan, or chitin also had no effect on phagocytosis of C. parapsilosis. Consistent with the differences noted in phagocytosis, neutrophils mediated damage to C. parapsilosis but not C. albicans in assays of residual metabolic activity. C. parapsilosis was more sensitive to oxidative stress, and inclusion of antioxidant in toxicity assays decreased neutrophil mediated damage, suggesting that generation of reactive oxygen species contributes to the toxicity mechanism. These data suggest that the interaction between neutrophils and Candida species is not uniform and may partially account for differences observed in the epidemiology and natural history of infections caused by these species.
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Affiliation(s)
- Jennifer R Linden
- Graduate Program in Pathobiology, Brown University, Providence, RI 02905, USA
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Linden JR, Maccani MA, Laforce-Nesbitt SS, Bliss JM. High efficiency opsonin-independent phagocytosis ofCandida parapsilosisby human neutrophils. Med Mycol 2010. [DOI: 10.3109/13693780903164566] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
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28
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Ferwerda B, Ferwerda G, Plantinga TS, Willment JA, van Spriel AB, Venselaar H, Elbers CC, Johnson MD, Cambi A, Huysamen C, Jacobs L, Jansen T, Verheijen K, Masthoff L, Morré SA, Vriend G, Williams DL, Perfect JR, Joosten LAB, Wijmenga C, van der Meer JWM, Adema GJ, Kullberg BJ, Brown GD, Netea MG. Human dectin-1 deficiency and mucocutaneous fungal infections. N Engl J Med 2009; 361:1760-7. [PMID: 19864674 PMCID: PMC2773015 DOI: 10.1056/nejmoa0901053] [Citation(s) in RCA: 553] [Impact Index Per Article: 36.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Mucocutaneous fungal infections are typically found in patients who have no known immune defects. We describe a family in which four women who were affected by either recurrent vulvovaginal candidiasis or onychomycosis had the early-stop-codon mutation Tyr238X in the beta-glucan receptor dectin-1. The mutated form of dectin-1 was poorly expressed, did not mediate beta-glucan binding, and led to defective production of cytokines (interleukin-17, tumor necrosis factor, and interleukin-6) after stimulation with beta-glucan or Candida albicans. In contrast, fungal phagocytosis and fungal killing were normal in the patients, explaining why dectin-1 deficiency was not associated with invasive fungal infections and highlighting the specific role of dectin-1 in human mucosal antifungal defense.
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Affiliation(s)
- Bart Ferwerda
- Department of Internal Medicine and the Nijmegen Institute for Infection, Inflammation, and Immunity, Radboud University Nijmegen, Nijmegen, The Netherlands
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Macrophage-mediated responses to Candida albicans in mice expressing the human immunodeficiency virus type 1 transgene. Infect Immun 2009; 77:4136-49. [PMID: 19564379 DOI: 10.1128/iai.00453-09] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The critical impairments of innate and adaptive immunity that cause susceptibility to mucosal candidiasis in human immunodeficiency virus (HIV) infection have not been fully determined. We therefore conducted an analysis of macrophage-mediated responses to Candida albicans in transgenic (Tg) mice expressing Nef, Env, and Rev of HIV type 1 (HIV-1) in CD4(+) T cells, dendritic cells, and macrophages and developing an AIDS-like disease (CD4C/HIV(MutA) Tg mice). Macrophages were successfully recruited to the oral and gastric mucosae of these Tg mice in response to chronic carriage of C. albicans and displayed polarization toward an alternatively activated phenotype. Functionally, peritoneal macrophages from uninfected Tg mice exhibited increased phagocytosis of C. albicans and enhanced production of interleukin 6 and monocyte chemoattractant protein 1, demonstrating that the HIV-1 transgene independently activates selected macrophage functions. Production of H(2)O(2) by macrophages from Tg mice primed with gamma interferon and treated with phorbol 12-myristate 13-acetate or C. albicans was moderately reduced, but expression of the HIV-1 transgene did not alter production of nitric oxide or reduce killing of C. albicans. A knockout of the inducible nitric oxide synthase (NOS2) gene in these Tg mice did not augment oral or gastrointestinal burdens during chronic carriage of C. albicans or cause systemic dissemination, likely due to a redundancy provided by partially preserved production of H(2)O(2) and oxygen-independent candidacidal mechanisms. Thus, the macrophage response to C. albicans is largely preserved in these Tg mice, and no functional macrophage defect appears to primarily determine the susceptibility to mucosal candidiasis.
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Fernández-Arenas E, Bleck CKE, Nombela C, Gil C, Griffiths G, Diez-Orejas R. Candida albicans actively modulates intracellular membrane trafficking in mouse macrophage phagosomes. Cell Microbiol 2009; 11:560-89. [PMID: 19134116 DOI: 10.1111/j.1462-5822.2008.01274.x] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The intracellular trafficking/survival strategies of the opportunistic human pathogen Candida albicans are poorly understood. Here we investigated the infection of RAW264.7 macrophages with a virulent wild-type (WT) filamentous C. albicans strain and a hyphal signalling-defective mutant (efg1Delta/cph1Delta). A comparative analysis of the acquisition by phagosomes of actin, and of early/late endocytic organelles markers of the different fungal strains was performed and related to Candida's survival inside macrophages. Our results show that both fungal strains have evolved a similar mechanism to subvert the 'lysosomal' system, as seen by the inhibition of the phagosome fusion with compartments enriched in the lysobisphosphatidic acid and the vATPase, and thereby the acquisition of a low pH from the outset of infection. Besides, the virulent WT strain displayed additional specific survival strategies to prevent its targeting to compartmentsdisplaying late endosomal/lysosomal features, such as induction of active recycling out of phagosomes of the lysosomal membrane protein LAMP-1, the lysosomal protease cathepsin D and preinternalized colloidal gold. Finally, both virulent and efg1Delta/cph1Delta mutant fungal strains actively suppressed the production of macrophage nitric oxide (NO), although their cell wall extracts were potent inducers of NO.
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Affiliation(s)
- Elena Fernández-Arenas
- Departamento de Microbiología II, Facultad de Farmacia, Universidad Complutense, 28040-Madrid, Spain
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Abstract
Both innate resistance and acquired cell-mediated immunity are involved in an anti-Candida response. Essential components of both the arms of the immune defense against infections by Candida spp. include phagocytic cells, i.e., polymorphonuclear neutrophils (PMNs) and mononuclear phagocytes. A powerful in vitro assay to assess host-pathogen interactions and study pathogenesis is the co-culture of phagocytic cells with a test fungus. The precise contribution of phagocytes to the host defense is usually assessed by determining phagocytosis and killing of Candida spp. blastoconidia. Dissection of the roles of various virulence factors in the infection process will involve the use of both in vitro and ex vivo assays. These assays are very useful as one of the approaches to determine the virulence factors of Candida spp., now that specific gene mutants are relatively easy to construct. In vitro studies involving specific cultured immune system cells can permit the analysis of interactions under controlled conditions. These studies provide an opportunity to monitor and compare host cell behavior upon challenge with wild-type or mutant strains of the pathogen.
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Diez-Orejas R, Fernández-Arenas E. Candida albicans–macrophage interactions: genomic and proteomic insights. Future Microbiol 2008; 3:661-81. [DOI: 10.2217/17460913.3.6.661] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Candida albicans infection is a significant cause of morbidity and mortality in immunocompromised patients. In vivo and in vitro models have been developed to study both the fungal and the mammalian immune responses. Phagocytic cells (i.e., macrophages) play a key role in innate immunity against C. albicans by capturing, killing and processing the pathogen for presentation to T cells. The use of microarray technology to study global fungal transcriptional changes after interaction with different host cells has revealed how C. albicans adapts to its environment. Proteomic tools complement molecular approaches and computational methods enable the formulation of relevant biological hypotheses. Therefore, the combination of genomics, proteomics and bioinformatics tools (i.e., network analyses) is a powerful strategy to better understand the biological situation of the fungus inside macrophages; part of the fungal population is killed while a significantly high percentage survives.
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Affiliation(s)
- Rosalía Diez-Orejas
- Departamento de Microbiología II, Facultad de Farmacia, Universidad Complutense, 28040 Madrid, Spain
| | - Elena Fernández-Arenas
- Centro de Biología Molecular Severo Ochoa (CBM-SO), Consejo Superior de Investigaciones Científicas (CSIC), Nicolás Cabrera 1, Cantoblanco, 28049 Madrid, Spain
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Immune defence mechanisms and immunoenhancement strategies in oropharyngeal candidiasis. Expert Rev Mol Med 2008; 10:e29. [PMID: 18847522 DOI: 10.1017/s1462399408000835] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/06/2022]
Abstract
The prevalence of oropharyngeal candidiasis continues to be high, mainly because of an increasing population of immunocompromised patients. Traditional treatment of oropharyngeal candidiasis has relied on the use of antimicrobial drugs. However, unsatisfactory results with drug monotherapy and the emergence of resistant strains have prompted investigations into the potential use of adjunctive immunoenhancing therapies for the treatment of these infections. Here we review the host-recognition systems of Candida albicans, the immune and inflammatory response to infection, and antifungal effector mechanisms. The potential of immune modulation as a therapeutic strategy in oropharyngeal candidiasis is also discussed.
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Schindler B, Segal E. Candida albicans metabolite affects the cytoskeleton and phagocytic activity of murine macrophages. Med Mycol 2008; 46:251-8. [PMID: 18404553 DOI: 10.1080/13693780701837157] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Abstract
Candida albicans is the most common opportunistic fungal pathogen of humans, causing systemic disease in immunocompromised patients. Host resistance to C. albicans infections is mediated predominantly by neutrophils and monocytes/macrophages. We have previously shown that exposure of a human epithelial cell line (HEp2) to C. albicans or to a culture filtrate of C. albicans caused actin rearrangement in the HEp2 cells. Since shifting of actin from the filamentous to the globular form may be crucial to the activity of phagocytes, we assessed in the present study the effect of the C. albicans metabolite (lyophilized culture filtrate) on the cytoskeleton of murine peritoneal macrophages and on their phagocytic activity. Our results showed a significant decrease in phagocytosis of C. albicans, ranging from 53-63% and a 25% reduction for C. glabrata cells. Using confocal laser scanning microscopy an actin rearrangement in the macrophages could be demonstrated that may be associated with the decrease of phagocytosis. We also tested the effect of mannan and of the secreted aspartic proteinase (Sap) inhibitor--pepstatin, on the activity of the metabolite in order to define the putative component and found no influence. In conclusion, our data indicate that a C. albicans metabolite affects phagocytic activity of macrophages, probably by alterations in their cytoskeleton.
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Affiliation(s)
- Ben Schindler
- Department of Human Microbiology, Sackler School of Medicine, Tel-Aviv University, Tel-Aviv, Israel
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35
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Wellington M, Dolan K, Haidaris CG. Monocyte responses to Candida albicans are enhanced by antibody in cooperation with antibody-independent pathogen recognition. ACTA ACUST UNITED AC 2007; 51:70-83. [PMID: 17610517 DOI: 10.1111/j.1574-695x.2007.00278.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Although most individuals are colonized with Candida albicans, only patients with insufficient or nonfunctional phagocytes develop life-threatening C. albicans disease. Because recognition of bacterial pathogens through phagocyte receptors for IgG (FcgammaR) is known to augment phagocyte responses, we postulated that antibody opsonization would enhance monocyte damage to C. albicans and subsequent tumor necrosis factor-alpha (TNF-alpha) production. After exposure to the human monocytic cell line THP-1, opsonized yeast showed an 89% decrease in metabolic activity, compared with 40% for unopsonized yeast (P<0.05). Culture supernatants contained 1316 pg mL(-1) of TNF-alpha after monocytes were exposed to opsonized yeast vs. 341 pg mL(-1) for unopsonized yeast (P=0.003). Similar results were obtained using peripheral blood mononuclear cells. Antibody opsonization of C. albicans germ tubes enhanced TNF-alpha production but did not affect organism damage. Antibody-dependent and antibody-independent factors were found to act synergistically to increase TNF-alpha production. ERK activation was important for both antibody-dependent and antibody-independent stimulation of TNF-alpha production, but not for monocyte-mediated organism damage. These data suggest that FcgammaR cooperates positively with antibody-independent recognition mechanisms in what may be a novel link between innate and adaptive immunity to C. albicans.
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Affiliation(s)
- Melanie Wellington
- Department of Pediatrics, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, USA.
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Taylor PR, Tsoni SV, Willment JA, Dennehy KM, Rosas M, Findon H, Haynes K, Steele C, Botto M, Gordon S, Brown GD. Dectin-1 is required for beta-glucan recognition and control of fungal infection. Nat Immunol 2006; 8:31-8. [PMID: 17159984 PMCID: PMC1888731 DOI: 10.1038/ni1408] [Citation(s) in RCA: 877] [Impact Index Per Article: 48.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2006] [Accepted: 10/11/2006] [Indexed: 12/19/2022]
Abstract
Beta-glucan is one of the most abundant polysaccharides in fungal pathogens, yet its importance in antifungal immunity is unclear. Here we show that deficiency of dectin-1, the myeloid receptor for beta-glucan, rendered mice susceptible to infection with Candida albicans. Dectin-1-deficient leukocytes demonstrated significantly impaired responses to fungi even in the presence of opsonins. Impaired leukocyte responses were manifested in vivo by reduced inflammatory cell recruitment after fungal infection, resulting in substantially increased fungal burdens and enhanced fungal dissemination. Our results establish a fundamental function for beta-glucan recognition by dectin-1 in antifungal immunity and demonstrate a signaling non-Toll-like pattern-recognition receptor required for the induction of protective immune responses.
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Affiliation(s)
- Philip R Taylor
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX13RE, UK
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37
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Vonk AG, Netea MG, van der Meer JWM, Kullberg BJ. Host defence against disseminated Candida albicans infection and implications for antifungal immunotherapy. Expert Opin Biol Ther 2006; 6:891-903. [PMID: 16918256 DOI: 10.1517/14712598.6.9.891] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The different manifestations of Candida albicans infection are dictated by an underlying defect in the immune response of the host. Protective immunity to disseminated candidiasis, the manifestation of C. albicans infection discussed in this review, has traditionally been ascribed to innate immunity with emphasis on the role of granulocytes. Lately, however, immunological studies have learned that host defence against disseminated candidiasis is based on a complex interplay between innate and cell-mediated immunity. Despite the availability of new antifungal agents, mortality associated with disseminated C. albicans infection remains high. Immunotherapy that augments host defence is an important strategic option in the battle against disseminated candidiasis. Here, the authors review the chronological events in the pathogenesis of disseminated candidiasis that aid in predicting the impact of existing immunotherapy and the development of future immunomodulating strategies.
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Affiliation(s)
- Alieke G Vonk
- Radboud University Nijmegen Medical Center, Department of Medicine 463, PO Box 9101, 6500 HB Nijmegen, The Netherlands
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38
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Abstract
The termination of the apoptotic programme occurs in most cases via recognition and clearance by phagocytes, especially the professional phagocytes, such as macrophages and immature dendritic cells. Engulfed cells do not simply disappear from the midst of living tissues. The fine-defined presentation of yielded self-antigens to T cells is a central event in the induction or the maintenance of the peripheral immune tolerance to self. Conversely, abnormality in this pathway may contribute to the pathogenesis of systemic and organ-specific autoimmune diseases. We herein reviewed the relationship between phagocytosis of apoptotic cells and immune regulation, especially the effects of engulfed apoptotic cells on immune tolerance and autoimmune diseases.
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Affiliation(s)
- G Liu
- Transplantation Biology Research Division, State Key Laboratory of Biomembrane and Membrane Biotechnology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
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39
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Tavanti A, Campa D, Bertozzi A, Pardini G, Naglik JR, Barale R, Senesi S. Candida albicans isolates with different genomic backgrounds display a differential response to macrophage infection. Microbes Infect 2006; 8:791-800. [PMID: 16473540 DOI: 10.1016/j.micinf.2005.09.016] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2005] [Revised: 08/31/2005] [Accepted: 09/28/2005] [Indexed: 11/16/2022]
Abstract
Few human pathogens possess the ability exhibited by Candida albicans to colonize and cause symptomatic infections at different body sites. The host immune system is the major factor determining whether this opportunistic yeast behaves as a commensal or as a pathogen, since C. albicans strains appear capable of expressing similar virulence factors in response to specific body-district cues. This report provides evidence showing that C. albicans isolates with diverse genomic backgrounds (b and c karyotypes) differently modulate their pathogenic potential when assayed in cocultures with human monocytic derived macrophages (THP-1 cells). Striking differences were observed in the ability to undergo bud-hypha transition, a relevant C. albicans virulence factor, between b and c karyotypes (P<0.0001) upon their internalization by macrophages. All c types were able to develop hyphal forms, resist intracellular killing, replicate, and escape from macrophages. The b type isolates, which were shown to be more efficiently ingested by THP-1 cells than the c type strains (P=0.013), were susceptible to intracellular killing and predominantly found as blastoconidia inside macrophages. Despite their different intracellular disposition, both b and c type isolates were equally able to undergo morphogenesis and to express NRG1 and HWP1 genes, markers of the bud-hypha transition program, during in vitro propagation. Since macrophages play a critical role in the host resistance to C. albicans, the different response of b and c isolates to macrophage infection suggests that the c type strains are better suited to behave as a more virulent strain cluster.
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Affiliation(s)
- Arianna Tavanti
- Dipartimento di Patologia Sperimentale, Biotecnologie Mediche, Infettivologia ed Epidemiologia, Sezione di Microbiologia e Virologia, Via San Zeno, 37-39, Università di Pisa, Pisa 56127, Italy
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40
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Dongari-Bagtzoglou A, Villar CC, Kashleva H. Candida albicans-infected oral epithelial cells augment the anti-fungal activity of human neutrophils in vitro. Med Mycol 2006; 43:545-9. [PMID: 16323311 DOI: 10.1080/13693780500064557] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
Oropharyngeal candidiasis (OPC) is the most common opportunistic infection in immunosuppressed patients. In OPC, Candida albicans persists intraepithelially triggering inflammatory events, without generally causing invasive infection. Since neutrophils play an important role in preventing invasive infection and since they establish contact with the microorganisms only within the epithelial cell layer, we examined the ability of Candida-infected oral epithelial cells to augment neutrophil-mediated hyphal damage in vitro. We found that challenge of neutrophils with hyphal organisms in the presence of C. albicans-infected oral epithelial cell supernatants resulted in a significantly greater suppression of hyphal cell metabolic activity compared to basal neutrophil anti-fungal function. Anti-hyphal activity in response to these supernatants was partly inhibited by neutralizing anti-IL-1alpha antibody and IL-1 receptor antagonist. Control supernatants from uninfected oral epithelial cells, as well as C. albicans conditioned-medium had a much less pronounced effect on neutrophil anti-fungal activity, which was not inhibited by these cytokine antagonists. We conclude that oral epithelial cells can act as activators of neutrophil anti-hyphal function, an effect that can be partly attributed to the generation of immunomodulatory cytokines during the interaction of oral mucosal cells with the pathogen.
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Affiliation(s)
- A Dongari-Bagtzoglou
- University Connecticut School of Dental Medicine, Department of Periodontology, Farmington, CT 06030-1710, USA.
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41
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Vonk AG, Wieland CW, Versteegen M, Verschueren IC, Netea MG, Joostent LAB, Verweij PE, Kullberg BJ. Influence of endogenous pro-inflammatory cytokines on neutrophil-mediated damage ofCandida albicanspseudohyphae, quantified in a modified tetrazolium dye assay. Med Mycol 2005; 43:551-7. [PMID: 16320497 DOI: 10.1080/13693780500057551] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
For quantitative assessment of polymorphonuclear granulocyte (PMN)-mediated pseudohyphal damage, an improved tetrazolium (2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide; XTT) dye assay was developed. The modified assay proved to be a reliable indicator of viable pseudohyphal inoculum sizes. In addition, the influence of various endogenous pro-inflammatory cytokines on the capacity of PMN to damage Candida albicans pseudohyphae was investigated. PMN obtained from mice in which the genes encoding for tumor necrosis factor-alpha/lymphotoxin-alpha (TNF/LT), interferon-gamma (IFNgamma), interleukin (IL)-1alpha, or IL-1beta were disrupted, showed a significantly reduced pseudohyphal damage capacity in comparison with control PMN. The reduction amounted 25% for TNF-/- LT-/-, 11% for IFNgamma-/-, 21% for IL-1alpha-/-, and 34% for IL-1alpha-/-beta-/- PMN. In contrast, deficiency of IL-12 or IL-18 did not result in a diminished capacity to damage pseudohyphae and the capacity of PMN to damage Candida pseudohyphae was even slightly increased by 10% in IL-18-/- mice. These data suggest that endogenous pro-inflammatory cytokines are able to modulate antihyphal activity of PMN, the main effector cells against disseminated candidiasis by virtue of their capacity to kill both Candida blastoconidia and pseudohyphae.
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Affiliation(s)
- Alieke G Vonk
- Department of Medicine, Division of General Internal Medicine, Radboud University Nijmegen Medical Center, The Netherlands
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42
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Netea MG, Gijzen K, Coolen N, Verschueren I, Figdor C, Van der Meer JWM, Torensma R, Kullberg BJ. Human dendritic cells are less potent at killing Candida albicans than both monocytes and macrophages. Microbes Infect 2004; 6:985-9. [PMID: 15345229 DOI: 10.1016/j.micinf.2004.05.013] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2004] [Accepted: 05/17/2004] [Indexed: 11/30/2022]
Abstract
Dendritic cells (DC) function as professional phagocytes to kill Candida albicans and subsequently present it to the adaptive immune system. Monocytes, macrophages and DC were generated from five individual donors and their Candida-killing capacity and cytokine release were assessed. Compared to monocytes and macrophages, DC from healthy volunteers were significantly less effective in C. albicans--stimulated cytokine release, killing of C. albicans blastoconidia and damaging of C. albicans hyphae. In conclusion, while important as antigen-presenting cells and initiators of the adaptive immune system, DC are poor in both intracellular killing and damaging of C. albicans hyphae. Effective handling of large numbers of C. albicans is the prime task of the innate immune system consisting of large numbers of neutrophils and monocytes.
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Affiliation(s)
- Mihai G Netea
- Department of Medicine, University Medical Center St. Radboud, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands
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Scarff KL, Ung KS, Nandurkar H, Crack PJ, Bird CH, Bird PI. Targeted disruption of SPI3/Serpinb6 does not result in developmental or growth defects, leukocyte dysfunction, or susceptibility to stroke. Mol Cell Biol 2004; 24:4075-82. [PMID: 15082799 PMCID: PMC387772 DOI: 10.1128/mcb.24.9.4075-4082.2004] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Protease inhibitor 6 (PI-6/SERPINB6) is a widely expressed nucleocytoplasmic serpin. It inhibits granulocyte cathepsin G and neuronal neuropsin, and it is thought to protect cells from death caused by ectopic release or internalization of protease during stress such as infection or cerebral ischemia. To probe the biological functions of PI-6, we generated mice lacking its ortholog (SPI3/Serpinb6). SPI3-deficient mice developed normally and were fertile, and no abnormal pathology or increased sensitivity to cerebral ischemia was observed. There were no perturbations in leukocyte development or numbers, and recruitment of leukocytes to the peritoneal cavity was normal. SPI3-deficient mice were equally susceptible as wild-type mice to systemic Candida albicans infection, although there was a slight decrease in the ability of neutrophils from SPI3-deficient mice to kill C. albicans in vitro. Increased levels of a related inhibitor Serpinb1 (monocyte/neutrophil elastase inhibitor) in the tissues of targeted mice suggests that compensation by other serpins reduces the impact of SPI3 deficiency in these animals and may explain the lack of a more obvious phenotype.
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Affiliation(s)
- Katrina L Scarff
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia
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44
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Netea MG, Sutmuller R, Hermann C, Van der Graaf CAA, Van der Meer JWM, van Krieken JH, Hartung T, Adema G, Kullberg BJ. Toll-Like Receptor 2 Suppresses Immunity againstCandida albicansthrough Induction of IL-10 and Regulatory T Cells. THE JOURNAL OF IMMUNOLOGY 2004; 172:3712-8. [PMID: 15004175 DOI: 10.4049/jimmunol.172.6.3712] [Citation(s) in RCA: 440] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Toll-like receptor (TLR) 2 and TLR4 play a pivotal role in recognition of Candida albicans. We demonstrate that TLR2(-/-) mice are more resistant to disseminated Candida infection, and this is associated with increased chemotaxis and enhanced candidacidal capacity of TLR2(-/-) macrophages. Although production of the proinflammatory cytokines TNF, IL-1alpha, and IL-1beta is normal, IL-10 release is severely impaired in the TLR2(-/-) mice. This is accompanied by a 50% decrease in the CD4+CD25+ regulatory T (Treg) cell population in TLR2(-/-) mice. In vitro studies confirmed that enhanced survival of Treg cells was induced by TLR2 agonists. The deleterious role of Treg cells on the innate immune response during disseminated candidiasis was underscored by the improved resistance to this infection after depletion of Treg cells. In conclusion, C. albicans induces immunosuppression through TLR2-derived signals that mediate increased IL-10 production and survival of Treg cells. This represents a novel mechanism in the pathogenesis of fungal infections.
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Affiliation(s)
- Mihai G Netea
- Department of Medicine,, University Medical Center St. Radboud, Nijmegen, The Netherlands
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Weijer S, Sewnath ME, de Vos AF, Florquin S, van der Sluis K, Gouma DJ, Takeda K, Akira S, van der Poll T. Interleukin-18 facilitates the early antimicrobial host response to Escherichia coli peritonitis. Infect Immun 2003; 71:5488-97. [PMID: 14500466 PMCID: PMC201063 DOI: 10.1128/iai.71.10.5488-5497.2003] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
To determine the role of endogenous interleukin-18 (IL-18) during peritonitis, IL-18 gene-deficient (IL-18 KO) mice and wild-type mice were intraperitoneally (i.p.) infected with Escherichia coli, the most common causative agent found in septic peritonitis. Peritonitis was associated with a bacterial dose-dependent increase in IL-18 concentrations in peritoneal fluid and plasma. After infection, IL-18 KO mice had significantly more bacteria in the peritoneal lavage fluid and were more susceptible for progression to systemic infection at 6 and 20 h postinoculation than wild-type mice. The relative inability of IL-18 KO mice to clear E. coli from the abdominal cavity was not due to an intrinsic defect in the phagocytosing capacity of their peritoneal macrophages or neutrophils. IL-18 KO mice displayed an increased neutrophil influx into the peritoneal cavity, but these migratory neutrophils were less activate, as reflected by a reduced CD11b surface expression. These data suggest that endogenous IL-18 plays an important role in the early antibacterial host response during E. coli-induced peritonitis.
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Affiliation(s)
- Sebastiaan Weijer
- Laboratory of Experimental Internal Medicine, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Room L0185, 1105 AZ Amsterdam, The Netherlands.
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Marr KA, Balajee SA, Hawn TR, Ozinsky A, Pham U, Akira S, Aderem A, Liles WC. Differential role of MyD88 in macrophage-mediated responses to opportunistic fungal pathogens. Infect Immun 2003; 71:5280-6. [PMID: 12933875 PMCID: PMC187297 DOI: 10.1128/iai.71.9.5280-5286.2003] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Toll-like receptors mediate macrophage recognition of microbial ligands, inducing expression of microbicidal molecules and cytokines via the adapter protein MyD88. We investigated the role of MyD88 in regulating murine macrophage responses to a pathogenic yeast (Candida albicans) and mold (Aspergillus fumigatus). Macrophages derived from bone marrow of MyD88-deficient mice (MyD88(-/-)) demonstrated impaired phagocytosis and intracellular killing of C. albicans compared to wild-type (MyD88(+/+)) macrophages. In contrast, ingestion and killing of A. fumigatus conidia was MyD88 independent. Cytokine production by MyD88(-/-) macrophages in response to C. albicans yeasts and hyphae was substantially decreased, but responses to A. fumigatus hyphae were preserved. These results provide evidence that MyD88 signaling is involved in phagocytosis and killing of live C. albicans, but not A. fumigatus. The differential role of MyD88 may represent one mechanism by which macrophages regulate innate responses specific to different pathogenic fungi.
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Affiliation(s)
- Kieren A Marr
- Fred Hutchinson Cancer Research Center and University of Washington, Seattle, 98109, USA.
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Marcil A, Harcus D, Thomas DY, Whiteway M. Candida albicans killing by RAW 264.7 mouse macrophage cells: effects of Candida genotype, infection ratios, and gamma interferon treatment. Infect Immun 2002; 70:6319-29. [PMID: 12379711 PMCID: PMC130362 DOI: 10.1128/iai.70.11.6319-6329.2002] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Phagocytic cells such as neutrophils and macrophages are potential components of the immune defense that protects mammals against Candida albicans infection. We have tested the interaction between the mouse macrophage cell line RAW 264.7 and a variety of mutant strains of C. albicans. We used an end point dilution assay to monitor the killing of C. albicans at low multiplicities of infection (MOIs). Several mutants that show reduced virulence in mouse systemic-infection models show reduced colony formation in the presence of macrophage cells. To permit analysis of the macrophage-Candida interaction at higher MOIs, we introduced a luciferase reporter gene into wild-type and mutant Candida cells and used loss of the luminescence signal to quantify proliferation. This assay gave results similar to those for the end point dilution assay. Activation of the macrophages with mouse gamma interferon did not enhance anti-Candida activity. Continued coculture of the Candida and macrophage cells eventually led to death of the macrophages, but for the RAW 264.7 cell line this was not due to apoptotic pathways involving caspase-8 or -9 activation. In general Candida cells defective in the formation of hyphae were both less virulent in animal models and more sensitive to macrophage engulfment and growth inhibition. However the nonvirulent, hypha-defective cla4 mutant line was considerably more resistant to macrophage-mediated inhibition than the wild-type strain. Thus although mutants sensitive to engulfment are typically less virulent in systemic-infection models, sensitivity to phagocytic macrophage cells is not the unique determinant of C. albicans virulence.
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Affiliation(s)
- A Marcil
- Genetics Group, Biotechnology Research Institute, National Research Council of Canada, Montreal, Quebec H4P 2R2, USA.
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