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Wei Z, Jin Q, Liu W, Liu T, He K, Jin Z, Chen M, Jiang Y, Qian Y, Hong H, Zhang D, Liu Q, Yang Z, Li Q. Gliotoxin elicits immunotoxicity in the early innate immune system of ducks. Poult Sci 2024; 103:103717. [PMID: 38643746 PMCID: PMC11039318 DOI: 10.1016/j.psj.2024.103717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Revised: 03/17/2024] [Accepted: 03/31/2024] [Indexed: 04/23/2024] Open
Abstract
Gliotoxin (GT) belongs to the epipolythiodioxopiperazine (ETP) family, which is considered a crucial virulence determinant among the secondary metabolites produced by Aspergillus fumigatus. The metabolites are commonly found in food and feed, contributing to the invasion and immune escape of Aspergillus fumigatus, thereby posing a significant threat to the health of livestock, poultry, and humans. Heterophil extracellular traps (HETs), a novel form of innate immune defense, have been documented in the chicken's innate immune systems for capturing and eliminating invading microbes. However, the effects and mechanisms of GT on the production of duck HETs in vitro remain unknown. In this study, we first confirmed the presence of HETs in duck innate immune systems and further investigated the molecular mechanism underlying GT-induced HETs release. Our results demonstrate that GT can trigger typical release of HETs in duck. The structures of GT-induced HETs structures were characterized by DNA decoration, citrullinated histones 3, and elastase. Furthermore, NADPH oxidase, glycolysis, ERK1/2 and p38 signaling pathway were found to regulate GT-induced HETs. In summary, our findings reveal that gliotoxin activates HETs release in the early innate immune system of duck while providing new insights into the immunotoxicity of GT towards ducks.
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Affiliation(s)
- Zhengkai Wei
- College of Veterinary Medicine, Southwest University, Chongqing, 400715, PR China.
| | - Qinqin Jin
- College of Life Sciences and Engineering, Foshan University, Foshan 528225, Guangdong Province, PR China
| | - Wei Liu
- College of Life Sciences and Engineering, Foshan University, Foshan 528225, Guangdong Province, PR China
| | - Tingting Liu
- College of Life Sciences and Engineering, Foshan University, Foshan 528225, Guangdong Province, PR China
| | - Kaifeng He
- College of Veterinary Medicine, Southwest University, Chongqing, 400715, PR China
| | - Zha Jin
- College of Life Sciences and Engineering, Foshan University, Foshan 528225, Guangdong Province, PR China
| | - Meiyi Chen
- College of Life Sciences and Engineering, Foshan University, Foshan 528225, Guangdong Province, PR China
| | - Yuqian Jiang
- College of Life Sciences and Engineering, Foshan University, Foshan 528225, Guangdong Province, PR China
| | - Yuxiao Qian
- College of Life Sciences and Engineering, Foshan University, Foshan 528225, Guangdong Province, PR China
| | - Hongrong Hong
- College of Life Sciences and Engineering, Foshan University, Foshan 528225, Guangdong Province, PR China
| | - Dezhi Zhang
- College of Veterinary Medicine, Southwest University, Chongqing, 400715, PR China
| | - Quan Liu
- College of Life Sciences and Engineering, Foshan University, Foshan 528225, Guangdong Province, PR China
| | - Zhengtao Yang
- College of Life Sciences and Engineering, Foshan University, Foshan 528225, Guangdong Province, PR China
| | - Qianyong Li
- College of Veterinary Medicine, Southwest University, Chongqing, 400715, PR China
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Dunne K, Reece E, McClean S, Doyle S, Rogers TR, Murphy P, Renwick J. Aspergillus fumigatus Supernatants Disrupt Bronchial Epithelial Monolayers: Potential Role for Enhanced Invasion in Cystic Fibrosis. J Fungi (Basel) 2023; 9:jof9040490. [PMID: 37108944 PMCID: PMC10141846 DOI: 10.3390/jof9040490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 04/14/2023] [Accepted: 04/14/2023] [Indexed: 04/29/2023] Open
Abstract
Aspergillus fumigatus is the most commonly isolated fungus in chronic lung diseases, with a prevalence of up to 60% in cystic fibrosis patients. Despite this, the impact of A. fumigatus colonisation on lung epithelia has not been thoroughly explored. We investigated the influence of A. fumigatus supernatants and the secondary metabolite, gliotoxin, on human bronchial epithelial cells (HBE) and CF bronchial epithelial (CFBE) cells. CFBE (F508del CFBE41o-) and HBE (16HBE14o-) trans-epithelial electrical resistance (TEER) was measured following exposure to A. fumigatus reference and clinical isolates, a gliotoxin-deficient mutant (ΔgliG) and pure gliotoxin. The impact on tight junction (TJ) proteins, zonula occludens-1 (ZO-1) and junctional adhesion molecule-A (JAM-A) were determined by western blot analysis and confocal microscopy. A. fumigatus conidia and supernatants caused significant disruption to CFBE and HBE TJs within 24 h. Supernatants from later cultures (72 h) caused the greatest disruption while ΔgliG mutant supernatants caused no disruption to TJ integrity. The ZO-1 and JAM-A distribution in epithelial monolayers were altered by A. fumigatus supernatants but not by ΔgliG supernatants, suggesting that gliotoxin is involved in this process. The fact that ΔgliG conidia were still capable of disrupting epithelial monolayers indicates that direct cell-cell contact also plays a role, independently of gliotoxin production. Gliotoxin is capable of disrupting TJ integrity which has the potential to contribute to airway damage, and enhance microbial invasion and sensitisation in CF.
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Affiliation(s)
- Katie Dunne
- Discipline of Clinical Microbiology, School of Medicine, Trinity College Dublin, D02 PN40 Dublin, Ireland
| | - Emma Reece
- Discipline of Clinical Microbiology, School of Medicine, Trinity College Dublin, D02 PN40 Dublin, Ireland
| | - Siobhán McClean
- School of Biomolecular and Biomedical Science, University College Dublin, Belfield, D04 V1W8 Dublin, Ireland
| | - Sean Doyle
- Department of Biology, Maynooth University, Maynooth, W23 F2K8 Kildare, Ireland
| | - Thomas R Rogers
- Discipline of Clinical Microbiology, School of Medicine, Trinity College Dublin, D02 PN40 Dublin, Ireland
| | - Philip Murphy
- Discipline of Clinical Microbiology, School of Medicine, Trinity College Dublin, D02 PN40 Dublin, Ireland
| | - Julie Renwick
- Discipline of Clinical Microbiology, School of Medicine, Trinity College Dublin, D02 PN40 Dublin, Ireland
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Dehghani Nazhvani A, Farhadi A, Badiee P, Keshvari H, Ashraf MJ, Pakdel F, Farzinnia G. Aspergillus Species and Human Papillomavirus Infections in Epithelial Tumors of Nasal and Paranasal Cavities. INTERNATIONAL JOURNAL OF CANCER MANAGEMENT 2023. [DOI: 10.5812/ijcm-133155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/29/2023]
Abstract
Background: There are diverse lesions originating from the paranasal sinuses and nasal cavity. Tobacco use, alcohol consumption, and malnutrition have been identified to play a role in the development of head and neck carcinomas. Recently, fungi and viruses have been recognized as potential causes of nasal cavity and paranasal tumors. Objectives: This study aimed at specifying the prevalence of Aspergillus and human papillomavirus (HPV) infections in the epithelial tumors of nasal cavity and paranasal sinuses. Methods: In this cross-sectional study, 57 paraffin-embedded tissue samples of malignant and benign lesions of the paranasal sinuses and nasal cavity were evaluated for the presence of Aspergillus and HPV DNA by nested polymerase chain reaction (nPCR) technique with specific primers. Results: Despite the absence of angular hyphae (acute angle) of the fungus on histopathological slides, overall, 10 (17.54%) out of 57 paraffin-embedded samples were found to be positive for Aspergillus species. However, HPV-DNA was not found in any of the samples. Conclusions: Our data suggest that fungal infections (especially aspergillosis) as an etiological factor can be contributed to the development of sinonasal cancer and, therefore, they should be considered in the management of patients with sinonasal cancer. In addition, PCR can provide an alternative to culture-dependent identification methods.
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Mahata PK, Dass RS, Gunti L, Thorat PA. First report on the metabolic characterization of Sterigmatocystin production by select Aspergillus species from the Nidulantes section in Foeniculum vulgare. Front Microbiol 2022; 13:958424. [PMID: 36090109 PMCID: PMC9459157 DOI: 10.3389/fmicb.2022.958424] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 08/03/2022] [Indexed: 12/16/2022] Open
Abstract
Spices are typically grown in climates that support the growth of toxigenic fungi and the production of mycotoxins. The Aspergilli described in this study, as well as the sterigmatocystin (STC) detected, are causes for concern due to their potential to induce food poisoning. One of the most well-known producers of the carcinogenic STC is Aspergillus nidulans. This research explores the occurrence of STC-producing fungi in Foeniculum vulgare, a spice that is marketed in India and other parts of the world. This innovative study details the mycotoxigenic potential of five Aspergilli belonging to Section Nidulantes, namely Aspergillus latus (02 isolates), Emericella quadrilineata (02 isolates), and Aspergillus nidulans (01 isolate), with respect to STC contamination. These five isolates of Aspergilli were screened to produce STC on yeast extract sucrose (YES) medium in a controlled environment with regard to light, temperature, pH, and humidity, among other variables. The expression patterns of regulatory genes, namely, aflR, laeA, pacC, fluG, flbA, pksA, and mtfA were studied on the Czapek–Dox agar (CDA) medium. STC biosynthesis by the test isolates was done in potato dextrose broth (PDB) under optimum conditions, followed by the extraction and purification of the broth using ethyl acetate. High-performance liquid chromatography (HPLC) with an ultraviolet (UV) detector was utilized to detect compounds in eluted samples. F. vulgare contains Aspergilli that have been shown to have mycotoxigenic potential, which can accumulate in the spice during its active growth and thereby cause the elaboration of mycotoxins.
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The Toxic Mechanism of Gliotoxins and Biosynthetic Strategies for Toxicity Prevention. Int J Mol Sci 2021; 22:ijms222413510. [PMID: 34948306 PMCID: PMC8705807 DOI: 10.3390/ijms222413510] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 12/09/2021] [Accepted: 12/13/2021] [Indexed: 12/13/2022] Open
Abstract
Gliotoxin is a kind of epipolythiodioxopiperazine derived from different fungi that is characterized by a disulfide bridge. Gliotoxins can be biosynthesized by a gli gene cluster and regulated by a positive GliZ regulator. Gliotoxins show cytotoxic effects via the suppression the function of macrophage immune function, inflammation, antiangiogenesis, DNA damage by ROS production, peroxide damage by the inhibition of various enzymes, and apoptosis through different signal pathways. In the other hand, gliotoxins can also be beneficial with different doses. Low doses of gliotoxin can be used as an antioxidant, in the diagnosis and treatment of HIV, and as an anti-tumor agent in the future. Gliotoxins have also been used in the control of plant pathogens, including Pythium ultimum and Sclerotinia sclerotiorum. Thus, it is important to elucidate the toxic mechanism of gliotoxins. The toxic mechanism of gliotoxins and biosynthetic strategies to reduce the toxicity of gliotoxins and their producing strains are summarized in this review.
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The Peroxiredoxin Asp f3 Acts as Redox Sensor in Aspergillus fumigatus. Genes (Basel) 2021; 12:genes12050668. [PMID: 33946853 PMCID: PMC8145481 DOI: 10.3390/genes12050668] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 04/24/2021] [Accepted: 04/27/2021] [Indexed: 11/16/2022] Open
Abstract
The human pathogenic fungus Aspergillus fumigatus is readily eradicated by the innate immunity of immunocompetent human hosts, but can cause severe infections, such as invasive aspergillosis (IA), in immunocompromised individuals. During infection, the fungal redox homeostasis can be challenged by reactive oxygen species (ROS), either derived from the oxidative burst of innate immune cells or the action of antifungal drugs. The peroxiredoxin Asp f3 was found to be essential to cause IA in mice, but how Asp f3 integrates with fungal redox homeostasis remains unknown. Here, we show that in vivo, Asp f3 acts as a sensor for ROS. While global transcription in fungal hyphae under minimal growth conditions was fully independent of Asp f3, a robust induction of the oxidative stress response required the presence of the peroxiredoxin. Hyphae devoid of Asp f3 failed to activate several redox active genes, like members of the gliotoxin biosynthesis gene cluster and integral members of the Afyap1 regulon, the central activator of the ROS defense machinery in fungi. Upon deletion of the asp f3 gene Afyap1 displayed significantly reduced nuclear localization during ROS exposure, indicating that Asp f3 can act as an intracellular redox sensor for several target proteins.
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Brown R, Priest E, Naglik JR, Richardson JP. Fungal Toxins and Host Immune Responses. Front Microbiol 2021; 12:643639. [PMID: 33927703 PMCID: PMC8076518 DOI: 10.3389/fmicb.2021.643639] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 03/08/2021] [Indexed: 12/11/2022] Open
Abstract
Fungi are ubiquitous organisms that thrive in diverse natural environments including soils, plants, animals, and the human body. In response to warmth, humidity, and moisture, certain fungi which grow on crops and harvested foodstuffs can produce mycotoxins; secondary metabolites which when ingested have a deleterious impact on health. Ongoing research indicates that some mycotoxins and, more recently, peptide toxins are also produced during active fungal infection in humans and experimental models. A combination of innate and adaptive immune recognition allows the host to eliminate invading pathogens from the body. However, imbalances in immune homeostasis often facilitate microbial infection. Despite the wide-ranging effects of fungal toxins on health, our understanding of toxin-mediated modulation of immune responses is incomplete. This review will explore the current understanding of fungal toxins and how they contribute to the modulation of host immunity.
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Affiliation(s)
| | | | | | - Jonathan P. Richardson
- Centre for Host-Microbiome Interactions, Faculty of Dentistry, Oral & Craniofacial Sciences, King’s College London, London, United Kingdom
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F. Q. Smith D, Casadevall A. Fungal immunity and pathogenesis in mammals versus the invertebrate model organism Galleria mellonella. Pathog Dis 2021; 79:ftab013. [PMID: 33544836 PMCID: PMC7981337 DOI: 10.1093/femspd/ftab013] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Accepted: 02/03/2021] [Indexed: 02/07/2023] Open
Abstract
In recent decades, Galleria mellonella (Lepidoptera: Pyralidae) have emerged as a model system to explore experimental aspects of fungal pathogenesis. The benefits of the G. mellonella model include being faster, cheaper, higher throughput and easier compared with vertebrate models. Additionally, as invertebrates, their use is subject to fewer ethical and regulatory issues. However, for G. mellonella models to provide meaningful insight into fungal pathogenesis, the G. mellonella-fungal interactions must be comparable to mammalian-fungal interactions. Indeed, as discussed in the review, studies suggest that G. mellonella and mammalian immune systems share many similarities, and fungal virulence factors show conserved functions in both hosts. While the moth model has opened novel research areas, many comparisons are superficial and leave large gaps of knowledge that need to be addressed concerning specific mechanisms underlying G. mellonella-fungal interactions. Closing these gaps in understanding will strengthen G. mellonella as a model for fungal virulence in the upcoming years. In this review, we provide comprehensive comparisons between fungal pathogenesis in mammals and G. mellonella from immunological and virulence perspectives. When information on an antifungal immune component is unknown in G. mellonella, we include findings from other well-studied Lepidoptera. We hope that by outlining this information available in related species, we highlight areas of needed research and provide a framework for understanding G. mellonella immunity and fungal interactions.
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Affiliation(s)
- Daniel F. Q. Smith
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, The Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA
| | - Arturo Casadevall
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, The Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA
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9
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Zhang C, Chen F, Liu X, Han X, Hu Y, Su X, Chen Y, Sun Y, Han L. Gliotoxin Induces Cofilin Phosphorylation to Promote Actin Cytoskeleton Dynamics and Internalization of Aspergillus fumigatus Into Type II Human Pneumocyte Cells. Front Microbiol 2019; 10:1345. [PMID: 31275272 PMCID: PMC6591310 DOI: 10.3389/fmicb.2019.01345] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Accepted: 05/29/2019] [Indexed: 01/27/2023] Open
Abstract
Aspergillus fumigatus is able to internalize into lung epithelial cells to escape from immune attack for further dissemination. We previously reported that gliotoxin, a major mycotoxin of A. fumigatus, promotes this internalization; however, the mechanism remained unclear. Here, we report that gliotoxin is able to induce cofilin phosphorylation in A549 type II human pneumocytes. Either too high or too low a level of cofilin phosphorylation blocked the gliotoxin-induced actin cytoskeleton rearrangement and A. fumigatus internalization. LIM domain kinase 1 (LIMK1) and its upstream small GTPases (Cdc42 and RhoA, but not Rac1) predominantly mediated the gliotoxin-induced cofilin phosphorylation and A. fumigatus internalization. Simultaneously, gliotoxin significantly stimulated an increase in cAMP; however, adding an antagonist of PKA did not block gliotoxin-induced A. fumigatus internalization. In vivo, exogenous gliotoxin helped gliotoxin synthesis deficient strain gliPΔ invade into the lung tissue and the lung fungal burden increased markedly in immunosuppressed mice. In conclusion, these data revealed a novel role of gliotoxin in inducing cofilin phosphorylation mostly through the Cdc42/RhoA-LIMK1 signaling pathway to promote actin cytoskeleton rearrangement and internalization of A. fumigatus into type II human pneumocytes.
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Affiliation(s)
- Changjian Zhang
- Chinese PLA Center for Disease Control and Prevention, Beijing, China.,Academy of Military Medical Sciences, Beijing, China
| | - Fangyan Chen
- Chinese PLA Center for Disease Control and Prevention, Beijing, China
| | - Xiaoyu Liu
- Chinese PLA Center for Disease Control and Prevention, Beijing, China.,Academy of Military Medical Sciences, Beijing, China
| | - Xuelin Han
- Chinese PLA Center for Disease Control and Prevention, Beijing, China
| | - Yingsong Hu
- Chinese PLA Center for Disease Control and Prevention, Beijing, China
| | - Xueting Su
- Chinese PLA Center for Disease Control and Prevention, Beijing, China
| | - Yong Chen
- Chinese PLA Center for Disease Control and Prevention, Beijing, China
| | - Yansong Sun
- Academy of Military Medical Sciences, Beijing, China
| | - Li Han
- Chinese PLA Center for Disease Control and Prevention, Beijing, China
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10
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König S, Pace S, Pein H, Heinekamp T, Kramer J, Romp E, Straßburger M, Troisi F, Proschak A, Dworschak J, Scherlach K, Rossi A, Sautebin L, Haeggström JZ, Hertweck C, Brakhage AA, Gerstmeier J, Proschak E, Werz O. Gliotoxin from Aspergillus fumigatus Abrogates Leukotriene B 4 Formation through Inhibition of Leukotriene A 4 Hydrolase. Cell Chem Biol 2019; 26:524-534.e5. [PMID: 30745237 DOI: 10.1016/j.chembiol.2019.01.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Revised: 08/23/2018] [Accepted: 01/02/2019] [Indexed: 12/14/2022]
Abstract
The epidithiodioxopiperazine gliotoxin is a virulence factor of Aspergillus fumigatus, the most important airborne fungal pathogen of humans. Gliotoxin suppresses innate immunity in invasive aspergillosis, particularly by compromising neutrophils, but the underlying molecular mechanisms remain elusive. Neutrophils are the first responders among innate immune cells recruited to sites of infection by the chemoattractant leukotriene (LT)B4 that is biosynthesized by 5-lipoxygenase and LTA4 hydrolase (LTA4H). Here, we identified gliotoxin as inhibitor of LTA4H that selectively abrogates LTB4 formation in human leukocytes and in distinct animal models. Gliotoxin failed to inhibit the formation of other eicosanoids and the aminopeptidase activity of the bifunctional LTA4H. Suppression of LTB4 formation by gliotoxin required the cellular environment and/or reducing conditions, and only the reduced form of gliotoxin inhibited LTA4H activity. Conclusively, gliotoxin suppresses the biosynthesis of the potent neutrophil chemoattractant LTB4 by direct interference with LTA4H thereby impairing neutrophil functions in invasive aspergillosis.
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Affiliation(s)
- Stefanie König
- Department of Pharmaceutical/Medicinal Chemistry, Institute of Pharmacy, Friedrich-Schiller-University Jena, 07743 Jena, Germany
| | - Simona Pace
- Department of Pharmaceutical/Medicinal Chemistry, Institute of Pharmacy, Friedrich-Schiller-University Jena, 07743 Jena, Germany
| | - Helmut Pein
- Department of Pharmaceutical/Medicinal Chemistry, Institute of Pharmacy, Friedrich-Schiller-University Jena, 07743 Jena, Germany
| | - Thorsten Heinekamp
- Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knoell Institute (HKI), 07745 Jena, Germany
| | - Jan Kramer
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, 60438 Frankfurt, Germany
| | - Erik Romp
- Department of Pharmaceutical/Medicinal Chemistry, Institute of Pharmacy, Friedrich-Schiller-University Jena, 07743 Jena, Germany
| | - Maria Straßburger
- Transfer Group Antiinfectives, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knoell Institute (HKI), 07745 Jena, Germany
| | - Fabiana Troisi
- Department of Pharmaceutical/Medicinal Chemistry, Institute of Pharmacy, Friedrich-Schiller-University Jena, 07743 Jena, Germany
| | - Anna Proschak
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, 60438 Frankfurt, Germany
| | - Jan Dworschak
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knoell Institute (HKI), 07745 Jena, Germany
| | - Kirstin Scherlach
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knoell Institute (HKI), 07745 Jena, Germany
| | - Antonietta Rossi
- Department of Pharmacy, School of Medicine, University of Naples Federico II, 80131 Naples, Italy
| | - Lidia Sautebin
- Department of Pharmacy, School of Medicine, University of Naples Federico II, 80131 Naples, Italy
| | - Jesper Z Haeggström
- Division of Physiological Chemistry II, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, 17177 Stockholm, Sweden
| | - Christian Hertweck
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knoell Institute (HKI), 07745 Jena, Germany; Friedrich-Schiller-University Jena, 07743 Jena, Germany
| | - Axel A Brakhage
- Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knoell Institute (HKI), 07745 Jena, Germany; Friedrich-Schiller-University Jena, 07743 Jena, Germany
| | - Jana Gerstmeier
- Department of Pharmaceutical/Medicinal Chemistry, Institute of Pharmacy, Friedrich-Schiller-University Jena, 07743 Jena, Germany
| | - Ewgenij Proschak
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, 60438 Frankfurt, Germany
| | - Oliver Werz
- Department of Pharmaceutical/Medicinal Chemistry, Institute of Pharmacy, Friedrich-Schiller-University Jena, 07743 Jena, Germany.
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11
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Rosowski EE, Knox BP, Archambault LS, Huttenlocher A, Keller NP, Wheeler RT, Davis JM. The Zebrafish as a Model Host for Invasive Fungal Infections. J Fungi (Basel) 2018; 4:jof4040136. [PMID: 30551557 PMCID: PMC6308935 DOI: 10.3390/jof4040136] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Revised: 12/10/2018] [Accepted: 12/11/2018] [Indexed: 12/14/2022] Open
Abstract
The zebrafish has become a widely accepted model host for studies of infectious disease, including fungal infections. The species is genetically tractable, and the larvae are transparent and amenable to prolonged in vivo imaging and small molecule screening. The aim of this review is to provide a thorough introduction into the published studies of fungal infection in the zebrafish and the specific ways in which this model has benefited the field. In doing so, we hope to provide potential new zebrafish researchers with a snapshot of the current toolbox and prior results, while illustrating how the model has been used well and where the unfulfilled potential of this model can be found.
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Affiliation(s)
- Emily E Rosowski
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI 53716, USA.
| | - Benjamin P Knox
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI 53716, USA.
| | - Linda S Archambault
- Department of Molecular and Biomedical Sciences, University of Maine, Orono, ME 04469, USA.
| | - Anna Huttenlocher
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI 53716, USA.
- Department of Pediatrics, University of Wisconsin-Madison, Madison, WI 53792, USA.
| | - Nancy P Keller
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI 53716, USA.
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI 53706, USA.
| | - Robert T Wheeler
- Department of Molecular and Biomedical Sciences, University of Maine, Orono, ME 04469, USA.
- Graduate School of Biomedical Sciences and Engineering, University of Maine, Orono, ME 04469, USA.
| | - J Muse Davis
- Stead Family Department of Pediatrics, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA.
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12
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Sheehan G, Nagl M, Kavanagh K. Exposure to N-chlorotaurine induces oxidative stress responses in Aspergillus fumigatus. J Med Microbiol 2018; 68:279-288. [PMID: 30543319 DOI: 10.1099/jmm.0.000900] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
PURPOSE The neutrophil-derived oxidant N-chlorotaurine (NCT) displays remarkable in vivo tolerability and efficacy against a range of pathogens. The aim of this study was to characterize the response of the pulmonary pathogen Aspergillus fumigatus to NCT. METHODOLOGY The effect of NCT on the growth and viability of A. fumigatus was characterized. NCT-induced alteration of amino acids and gliotoxin from A. fumigatus mycelium was assessed. Label-free shotgun quantitative proteomic analysis was performed on A. fumigatus exposed to NCT for 24 h. RESULTS Incubation of A. fumigatus with NCT at concentrations ranging from 6.8 to 55 mM decreased conidial growth and viability, and mycelium biomass relative to the controls. Exposure to NCT (13.77 mM) resulted in increased amino acids and gliotoxin levels from A. fumigatus mycelium. Exposure of A. fumigatus mycelium to NCT (6.8 mM) revealed an enrichment in proteins associated with the ribosome, transcription and translation and non-ribosomal peptide biosynthesis (e.g. Pes1, Pes3), which play an essential role in oxidative stress resistance in A. fumigatus. A decrease in the abundance of proteins associated with fumagillin and pseurotin biosynthesis highlighted the anti-virulence activity of NCT. CONCLUSION These results indicate that NCT induces an oxidative stress response in A. fumigatus as evidenced by alterations in the proteome and inhibits conidial and mycelial growth. Clinical investigations of topical application of NCT to treat Aspergillus infections are encouraged.
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Affiliation(s)
- Gerard Sheehan
- 1Medical Mycology Laboratory, Department of Biology, Maynooth University, Maynooth, Co. Kildare, Ireland
| | - Markus Nagl
- 2Division of Hygiene and Medical Microbiology, Medical University of Innsbruck, Innsbruck, Austria
| | - Kevin Kavanagh
- 1Medical Mycology Laboratory, Department of Biology, Maynooth University, Maynooth, Co. Kildare, Ireland
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Arias M, Santiago L, Vidal-García M, Redrado S, Lanuza P, Comas L, Domingo MP, Rezusta A, Gálvez EM. Preparations for Invasion: Modulation of Host Lung Immunity During Pulmonary Aspergillosis by Gliotoxin and Other Fungal Secondary Metabolites. Front Immunol 2018; 9:2549. [PMID: 30459771 PMCID: PMC6232612 DOI: 10.3389/fimmu.2018.02549] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Accepted: 10/17/2018] [Indexed: 12/12/2022] Open
Abstract
Pulmonary aspergillosis is a severe infectious disease caused by some members of the Aspergillus genus, that affects immunocompetent as well as immunocompromised patients. Among the different disease forms, Invasive Aspergillosis is the one causing the highest mortality, mainly, although not exclusively, affecting neutropenic patients. This genus is very well known by humans, since different sectors like pharmaceutical or food industry have taken advantage of the biological activity of some molecules synthetized by the fungus, known as secondary metabolites, including statins, antibiotics, fermentative compounds or colorants among others. However, during infection, in response to a hostile host environment, the fungal secondary metabolism is activated, producing different virulence factors to increase its survival chances. Some of these factors also contribute to fungal dissemination and invasion of adjacent and distant organs. Among the different secondary metabolites produced by Aspergillus spp. Gliotoxin (GT) is the best known and better characterized virulence factor. It is able to generate reactive oxygen species (ROS) due to the disulfide bridge present in its structure. It also presents immunosuppressive activity related with its ability to kill mammalian cells and/or inactivate critical immune signaling pathways like NFkB. In this comprehensive review, we will briefly give an overview of the lung immune response against Aspergillus as a preface to analyse the effect of different secondary metabolites on the host immune response, with a special attention to GT. We will discuss the results reported in the literature on the context of the animal models employed to analyse the role of GT as virulence factor, which is expected to greatly depend on the immune status of the host: why should you hide when nobody is seeking for you? Finally, GT immunosuppressive activity will be related with different human diseases predisposing to invasive aspergillosis in order to have a global view on the potential of GT to be used as a target to treat IA.
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Affiliation(s)
- Maykel Arias
- Instituto de Carboquímica ICB-CSIC, Zaragoza, Spain
- Immune Effector Cells Group, Aragón Health Research Institute (IIS Aragón), Biomedical Research Centre of Aragón (CIBA), Zaragoza, Spain
| | - Llipsy Santiago
- Immune Effector Cells Group, Aragón Health Research Institute (IIS Aragón), Biomedical Research Centre of Aragón (CIBA), Zaragoza, Spain
- Department of Biochemistry and Molecular and Cell Biology, Fac. Ciencias, University of Zaragoza, Zaragoza, Spain
| | - Matxalen Vidal-García
- Immune Effector Cells Group, Aragón Health Research Institute (IIS Aragón), Biomedical Research Centre of Aragón (CIBA), Zaragoza, Spain
- Servicio de Microbiología - Hospital Universitario Miguel Servet, Zaragoza, Spain
| | | | - Pilar Lanuza
- Immune Effector Cells Group, Aragón Health Research Institute (IIS Aragón), Biomedical Research Centre of Aragón (CIBA), Zaragoza, Spain
- Department of Biochemistry and Molecular and Cell Biology, Fac. Ciencias, University of Zaragoza, Zaragoza, Spain
| | - Laura Comas
- Instituto de Carboquímica ICB-CSIC, Zaragoza, Spain
- Immune Effector Cells Group, Aragón Health Research Institute (IIS Aragón), Biomedical Research Centre of Aragón (CIBA), Zaragoza, Spain
- Department of Biochemistry and Molecular and Cell Biology, Fac. Ciencias, University of Zaragoza, Zaragoza, Spain
| | | | - Antonio Rezusta
- Servicio de Microbiología - Hospital Universitario Miguel Servet, Zaragoza, Spain
- Department of Microbiology, Preventive Medicine and Public Health, University of Zaragoza, Zaragoza, Spain
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The Human Cathelicidin Antimicrobial Peptide LL-37 Promotes the Growth of the Pulmonary Pathogen Aspergillus fumigatus. Infect Immun 2018; 86:IAI.00097-18. [PMID: 29712727 DOI: 10.1128/iai.00097-18] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Accepted: 04/20/2018] [Indexed: 12/14/2022] Open
Abstract
The pulmonary mucus of cystic fibrosis (CF) patients displays elevated levels of the cathelicidin antimicrobial peptide LL-37, and the aim of this work was to assess the effect of LL-37 on the growth of Aspergillus fumigatus, a common pathogen of CF patients. Exposure of A. fumigatus to LL-37 and its derived fragment RK-31 (1.95 μg/ml) for 24 h had a positive effect on growth (199.94% ± 6.172% [P < 0.05] and 218.20% ± 4.63% [P < 0.05], respectively), whereas scrambled LL-37 peptide did not (85.12% ± 2.92%). Exposure of mycelium (preformed for 24 h) to 5 μg/ml intact LL-37 for 48 h increased hyphal wet weight (4.37 ± 0.23 g, P < 0.001) compared to the control (2.67 ± 0.05 g) and scrambled LL-37 (2.23 ± 0.09 g) treatments. Gliotoxin secretion from LL-37 exposed hyphae (169.1 ± 6.36 ng/mg hyphae, P < 0.05) was increased at 24 h compared to the results seen with the control treatment (102 ± 18.81 ng/mg hyphae) and the scrambled LL-37 treatment (96.09 ± 15.15 ng/mg hyphae). Shotgun proteomic analysis of 24-h LL-37-treated hyphae revealed an increase in the abundance of proteins associated with growth (eukaryotic translation initiation factor 5A [eIF-5A] [16.3-fold increased]), tissue degradation (aspartic endopeptidase [4.7-fold increased]), and allergic reactions (Asp F13 [10-fold increased]). By 48 h, there was an increase in protein levels indicative of cellular stress (glutathione peroxidase [9-fold increased]), growth (eIF-5A [6-fold increased]), and virulence (RNase mitogillin [3.7-fold increased]). These results indicate that LL-37 stimulates A. fumigatus growth and that this stimulation can result in increased fungal growth and secretion of toxins in the lungs of CF patients.
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Brandão IDSL, Oliveira-Moraes HMDS, Souza Motta CMD, Oliveira NTD, Magalhães OMC. Elastin increases biofilm and extracellular matrix production of Aspergillus fumigatus. Braz J Microbiol 2018; 49:675-682. [PMID: 29452851 PMCID: PMC6066782 DOI: 10.1016/j.bjm.2017.10.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Revised: 09/23/2017] [Accepted: 10/02/2017] [Indexed: 11/18/2022] Open
Abstract
Aspergillus fumigatus is an opportunistic saprobe fungus that accounts for 90% of cases of pulmonary aspergillosis in immunosuppressed patients and is known for its angiotropism. When it reaches the respiratory tract, A. fumigatus interacts with structural components and blood vessels of the lungs, such as elastin. To understand the effect of this structural component, we examined the effect of elastin on the production and development of the biofilm of A. fumigatus. In RPMI containing 10 mg/mL of elastin, a significant increase (absorbance p < 0.0001; dry weight p < 0.0001) in the production of biofilm was observed in comparison to when RPMI was used alone, reaching a maximum growth of 18.8 mg (dry weight) of biofilm in 72 h. In addition, elastin stimulates the production (p = 0.0042) of extracellular matrix (ECM) and decreases (p = 0.005) the hydrophobicity during the development of the biofilm. These results suggest that elastin plays an important role in the growth of A. fumigatus and that it participates in the formation of thick biofilm.
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Affiliation(s)
- Ildnay de Souza Lima Brandão
- Universidade Federal de Pernambuco, Centro de Ciências Biológicas, Departamento de Micologia, Cidade Universitária, PE, Brazil
| | | | - Cristina Maria de Souza Motta
- Universidade Federal de Pernambuco, Centro de Ciências Biológicas, Departamento de Micologia, Pernambuco, PE, Brazil
| | - Neiva Tinti de Oliveira
- Universidade Federal de Pernambuco, Centro de Ciências Biológicas, Departamento de Micologia, Pernambuco, PE, Brazil
| | - Oliane Maria Correia Magalhães
- Universidade Federal de Pernambuco, Centro de Ciências Biológicas, Departamento de Micologia, Cidade Universitária, PE, Brazil.
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Saleh AA, Jones GW, Tinley FC, Delaney SF, Alabbadi SH, Fenlon K, Doyle S, Owens RA. Systems impact of zinc chelation by the epipolythiodioxopiperazine dithiol gliotoxin in Aspergillus fumigatus: a new direction in natural product functionality. Metallomics 2018; 10:854-866. [DOI: 10.1039/c8mt00052b] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Dithiol gliotoxin (DTG) is a zinc chelator and an inability to dissipate DTG in Aspergillus fumigatus is associated with multiple impacts which are linked to zinc chelation.
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Affiliation(s)
| | - Gary W. Jones
- Department of Biology
- Maynooth University
- Co. Kildare
- Ireland
- Centre for Biomedical Research
| | | | | | | | - Keith Fenlon
- Department of Biology
- Maynooth University
- Co. Kildare
- Ireland
| | - Sean Doyle
- Department of Biology
- Maynooth University
- Co. Kildare
- Ireland
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Boral H, Metin B, Döğen A, Seyedmousavi S, Ilkit M. Overview of selected virulence attributes in Aspergillus fumigatus, Candida albicans, Cryptococcus neoformans, Trichophyton rubrum, and Exophiala dermatitidis. Fungal Genet Biol 2017; 111:92-107. [PMID: 29102684 DOI: 10.1016/j.fgb.2017.10.008] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Revised: 10/24/2017] [Accepted: 10/27/2017] [Indexed: 12/13/2022]
Abstract
The incidence of fungal diseases has been increasing since 1980, and is associated with excessive morbidity and mortality, particularly among immunosuppressed patients. Of the known 625 pathogenic fungal species, infections caused by the genera Aspergillus, Candida, Cryptococcus, and Trichophyton are responsible for more than 300 million estimated episodes of acute or chronic infections worldwide. In addition, a rather neglected group of opportunistic fungi known as black yeasts and their filamentous relatives cause a wide variety of recalcitrant infections in both immunocompetent and immunosuppressed hosts. This article provides an overview of selected virulence factors that are known to suppress host immunity and enhance the infectivity of these fungi.
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Affiliation(s)
- Hazal Boral
- Division of Mycology, Department of Microbiology, Faculty of Medicine, University of Çukurova, Adana, Turkey
| | - Banu Metin
- Department of Food Engineering, Faculty of Engineering and Natural Sciences, Istanbul Sabahattin Zaim University, Istanbul, Turkey
| | - Aylin Döğen
- Department of Pharmaceutical Microbiology, Faculty of Pharmacy, University of Mersin, Mersin, Turkey
| | - Seyedmojtaba Seyedmousavi
- Department of Medical Microbiology, Radboud University Medical Center, Nijmegen, The Netherlands; Invasive Fungi Research Center, Mazandaran University of Medical Sciences, Sari, Iran; Center of Excellence for Infection Biology and Antimicrobial Pharmacology, Tehran, Iran
| | - Macit Ilkit
- Division of Mycology, Department of Microbiology, Faculty of Medicine, University of Çukurova, Adana, Turkey.
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18
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Shen Y, Zhang X, Lin W, Wan C, Li Q, Jiang Y. Liquid-based cytopathology test as a novel method to identify Aspergillus in patients with pulmonary aspergillosis. Sci Rep 2017; 7:7528. [PMID: 28790413 PMCID: PMC5548770 DOI: 10.1038/s41598-017-07564-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Accepted: 06/27/2017] [Indexed: 02/05/2023] Open
Abstract
Conventional cytopathology examination of respiratory samples can aid in identifying Aspergillus but with poor sensitivity, so this study aimed to assess the potential of the liquid-based cytopathology test (LCT) for improving the identification of Aspergillus in respiratory samples following Papanicolaou's or Special staining with Grocott's methenamine silver or periodic acid-Schiff staining. Paired bronchial brushing samples (n = 54) and sputum samples (n = 117) from 171 patients with pulmonary aspergillosis were prepared as slides using either conventional cytopathology or SurePath LCT. LCT slides were generally superior to conventional slides, showing smaller cell monolayer surface area, clearer background and more distinct stereoscopic cytological features. For Papanicolaou's staining, LCT-prepared slides allowed a higher positive rate of Aspergillus identification than conventional slides for bronchial brushing samples (59.25% vs. 20.37%, P < 0.05) and sputum samples (29.05% vs. 8.55%, P < 0.05). Similarly, Special staining of LCT-prepared slides showed a higher positive rate of Aspergillus identification for bronchial brushing samples (83.33% vs. 57.41%, P < 0.05) and sputum samples (43.59% vs. 19.66%, P < 0.05). This preliminary study suggests that LCT may be better than conventional slide preparation for identifying Aspergillus in respiratory samples from patients with pulmonary aspergillosis.
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Affiliation(s)
- Yongchun Shen
- Department of Respiratory and Critical Care Medicine, West China Hospital of Sichuan University and Division of Pulmonary Diseases, State Key Laboratory of Biotherapy of China, Chengdu, 610041, China
| | - Xiaorong Zhang
- Department of Pathology, The First Affiliated Hospital of Jiujiang University, Jiujiang, 332005, China
| | - Wenyi Lin
- Department of Pathology, Chengdu Womens' and Children's Central Hospital, Chengdu, 610091, China
| | - Chun Wan
- Department of Respiratory and Critical Care Medicine, West China Hospital of Sichuan University and Division of Pulmonary Diseases, State Key Laboratory of Biotherapy of China, Chengdu, 610041, China
| | - Qiyuan Li
- Department of Pathology, West China Hospital of Sichuan University, Chengdu, 610041, China
| | - Yong Jiang
- Department of Pathology, West China Hospital of Sichuan University, Chengdu, 610041, China.
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Alonso V, Cavaglieri L, Ramos AJ, Torres A, Marin S. Modelling the effect of pH and water activity in the growth of Aspergillus fumigatus isolated from corn silage. J Appl Microbiol 2017; 122:1048-1056. [PMID: 28052586 DOI: 10.1111/jam.13395] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Revised: 12/02/2016] [Accepted: 12/19/2016] [Indexed: 10/20/2022]
Abstract
AIMS The aim of this work was to use mathematical kinetic modelling to assess the combined effects of aW, pH, O2 availability and temperature on the growth rate and time to growth of Aspergillus fumigatus strains isolated from corn silage. METHODS AND RESULTS A full factorial design was used in which two factors were assayed: pH and aW . The aW levels assayed were 0·80, 0·85, 0·90, 0·92, 0·94, 0·96, 0·98 and 0·99. The levels of pH assayed were 3·5, 4, 4·5, 5, 6, 7, 7·5 and 8. The assay was performed at normal oxygen tension at 25 and 37°C, and at reduced oxygen tension at 25°C. Two strains of A. fumigatus isolated from corn silage were used. Kinetic models were built to predict growth of the strain under the assayed conditions. The cardinal models gave a good quality fit for radial growth rate data. The results indicate that the environmental conditions which take place during silage production, while limiting the growth of most micro-organisms, would not be able to control A. fumigatus. Moreover, pH levels in silage, far from limiting its growth, are also close to its optimum. Carbon dioxide at 5% in the environment did not significantly affect its growth. CONCLUSIONS A need for a further and controlled acidification of the silage exists, as no growth of A. fumigatus was observed at pH 3·5, as long as the organoleptic characteristics of the silage are not much compromised. SIGNIFICANCE AND IMPACT OF THE STUDY Aspergillus fumigatus is one of the major opportunistic pathogens able to cause illness such as allergic bronchopulmonary aspergillosis, aspergilloma and invasive aspergillosis to rural workers. Exposure of animals to A. fumigatus spores can result in infections, particularly in those organs exposed to external invasion, such as the airways, mammary gland and uterus at birth.
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Affiliation(s)
- V Alonso
- Departamento de Microbiología e Inmunología, Universidad Nacional de Río Cuarto, Río Cuarto, Córdoba, Argentina.,Member of Research Career CONICET, Ciudad Autónoma de Buenos Aires, Argentina
| | - L Cavaglieri
- Departamento de Microbiología e Inmunología, Universidad Nacional de Río Cuarto, Río Cuarto, Córdoba, Argentina.,Member of Research Career CONICET, Ciudad Autónoma de Buenos Aires, Argentina
| | - A J Ramos
- Food Technology Department, Lleida University, UTPV-XaRTA, Agrotecnic Center, Lleida, Spain
| | - A Torres
- Departamento de Microbiología e Inmunología, Universidad Nacional de Río Cuarto, Río Cuarto, Córdoba, Argentina.,Member of Research Career CONICET, Ciudad Autónoma de Buenos Aires, Argentina
| | - S Marin
- Food Technology Department, Lleida University, UTPV-XaRTA, Agrotecnic Center, Lleida, Spain
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20
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Konstantinovas C, de Oliveira Mendes TA, Vannier-Santos MA, Lima-Santos J. Modulation of Human Immune Response by Fungal Biocontrol Agents. Front Microbiol 2017; 8:39. [PMID: 28217107 PMCID: PMC5289975 DOI: 10.3389/fmicb.2017.00039] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Accepted: 01/06/2017] [Indexed: 01/29/2023] Open
Abstract
Although the vast majority of biological control agents is generally regarded as safe for humans and environment, the increased exposure of agriculture workers, and consumer population to fungal substances may affect the immune system. Those compounds may be associated with both intense stimulation, resulting in IgE-mediated allergy and immune downmodulation induced by molecules such as cyclosporin A and mycotoxins. This review discusses the potential effects of biocontrol fungal components on human immune responses, possibly associated to infectious, inflammatory diseases, and defective defenses.
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Affiliation(s)
- Cibele Konstantinovas
- Departamento de Ciências Biológicas, Universidade Estadual de Santa Cruz Ilhéus, Brazil
| | | | - Marcos A Vannier-Santos
- Biologia Celular Parasitária, Instituto Gonçalo Moniz, Fundação Oswaldo Cruz Salvador, Brazil
| | - Jane Lima-Santos
- Departamento de Ciências Biológicas, Universidade Estadual de Santa Cruz Ilhéus, Brazil
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21
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Regulation of Secondary Metabolism by the Velvet Complex Is Temperature-Responsive in Aspergillus. G3-GENES GENOMES GENETICS 2016; 6:4023-4033. [PMID: 27694115 PMCID: PMC5144971 DOI: 10.1534/g3.116.033084] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Sensing and responding to environmental cues is critical to the lifestyle of filamentous fungi. How environmental variation influences fungi to produce a wide diversity of ecologically important secondary metabolites (SMs) is not well understood. To address this question, we first examined changes in global gene expression of the opportunistic human pathogen, Aspergillus fumigatus, after exposure to different temperature conditions. We found that 11 of the 37 SM gene clusters in A. fumigatus were expressed at higher levels at 30° than at 37°. We next investigated the role of the light-responsive Velvet complex in environment-dependent gene expression by examining temperature-dependent transcription profiles in the absence of two key members of the Velvet protein complex, VeA and LaeA. We found that the 11 temperature-regulated SM gene clusters required VeA at 37° and LaeA at both 30 and 37° for wild-type levels of expression. Interestingly, four SM gene clusters were regulated by VeA at 37° but not at 30°, and two additional ones were regulated by VeA at both temperatures but were substantially less so at 30°, indicating that the role of VeA and, more generally of the Velvet complex, in the regulation of certain SM gene clusters is temperature-dependent. Our findings support the hypothesis that fungal secondary metabolism is regulated by an intertwined network of transcriptional regulators responsive to multiple environmental factors.
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23
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Al-Bader N, Sheppard DC. Aspergillosis and stem cell transplantation: An overview of experimental pathogenesis studies. Virulence 2016; 7:950-966. [PMID: 27687755 DOI: 10.1080/21505594.2016.1231278] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Invasive aspergillosis is a life-threatening infection caused by the opportunistic filamentous fungus Aspergillus fumigatus. Patients undergoing haematopoietic stem cell transplant (HSCT) for the treatment of hematological malignancy are at particularly high risk of developing this fatal infection. The susceptibility of HSCT patients to infection with A. fumigatus is a consequence of a complex interplay of both fungal and host factors. Here we review our understanding of the host-pathogen interactions underlying the susceptibility of the immunocompromised host to infection with A. fumigatus with a focus on the experimental validation of fungal and host factors relevant to HSCT patients. These include fungal factors such as secondary metabolites, cell wall constituents, and metabolic adaptations that facilitate immune evasion and survival within the host microenvironment, as well as the innate and adaptive immune responses involved in host defense against A. fumigatus.
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Affiliation(s)
- Nadia Al-Bader
- a Departments of Medicine, Microbiology and Immunology , McGill University , Montréal , Québec , Canada
| | - Donald C Sheppard
- a Departments of Medicine, Microbiology and Immunology , McGill University , Montréal , Québec , Canada.,b Infectious Diseases in Global Health Program, Research Institute of the McGill University Health Center, McGill University , Montréal , Québec , Canada
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Gliotoxin Suppresses Macrophage Immune Function by Subverting Phosphatidylinositol 3,4,5-Trisphosphate Homeostasis. mBio 2016; 7:e02242. [PMID: 27048806 PMCID: PMC4817266 DOI: 10.1128/mbio.02242-15] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Aspergillus fumigatus, an opportunistic fungal pathogen, spreads in the environment by releasing numerous conidia that are capable of reaching the small alveolar airways of mammalian hosts. In otherwise healthy individuals, macrophages are responsible for rapidly phagocytosing and eliminating these conidia, effectively curbing their germination and consequent invasion of pulmonary tissue. However, under some circumstances, the fungus evades phagocyte-mediated immunity and persists in the respiratory tree. Here, we report that A. fumigatus escapes macrophage recognition by strategically targeting phosphatidylinositol 3,4,5-trisphosphate [PtdIns(3,4,5)P3] metabolism through gliotoxin, a potent immunosuppressive mycotoxin. Time-lapse microscopy revealed that, in response to the toxin, macrophages cease to ruffle, undergo abrupt membrane retraction, and fail to phagocytose large targets effectively. Gliotoxin was found to prevent integrin activation and interfere with actin dynamics, both of which are instrumental for phagocytosis; similar effects were noted in immortalized and primary phagocytes. Detailed studies of the underlying molecular mechanisms of toxicity revealed that inhibition of phagocytosis is attributable to impaired accumulation of PtdIns(3,4,5)P3 and the associated dysregulation of downstream effectors, including Rac and/or Cdc42. Strikingly, in response to the diacylglycerol mimetic phorbol 12-myristate 13-acetate, gliotoxin-treated macrophages reactivate beta integrins, reestablish actin dynamics, and regain phagocytic capacity, despite the overt absence of plasmalemmal PtdIns(3,4,5)P3. Together, our findings identify phosphoinositide metabolism as a critical upstream target of gliotoxin and also indicate that increased diacylglycerol levels can bypass the requirement for PtdIns(3,4,5)P3 signaling during membrane ruffling and phagocytosis. Aspergillus fumigatus is the most frequent cause of human infections in the Aspergillus genus. In immunocompromised populations, invasive aspergillosis (IA) is associated with a mortality rate of up to 90%, and current antifungal therapies have failed to prevent or reverse the infection. Therefore, a deeper understanding of the interactions between A. fumigatus and its host is required. In healthy humans, alveolar macrophages can ingest and eliminate fungal spores, thus limiting their germination into mycotoxin-producing hyphae. Our studies reveal that gliotoxin—the most abundant Aspergillus mycotoxin—undermines the ability of phagocytes to carry out their protective functions. By targeting PtdIns(3,4,5)P3 signaling and downregulating phagocytic immune defenses, the toxin could also exacerbate polymicrobial infections. Notably, we were able to reverse gliotoxin toxicity by addition of diacylglycerol analogues, which may provide the basis for therapeutic interventions.
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25
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rtfA, a putative RNA-Pol II transcription elongation factor gene, is necessary for normal morphological and chemical development in Aspergillus flavus. Appl Microbiol Biotechnol 2016; 100:5029-41. [PMID: 27020290 DOI: 10.1007/s00253-016-7418-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Revised: 02/22/2016] [Accepted: 02/24/2016] [Indexed: 01/05/2023]
Abstract
The filamentous fungus Aspergillus flavus is an agriculturally important opportunistic plant pathogen that produces potent carcinogenic compounds called aflatoxins. We identified the A. flavus rtfA gene, the ortholog of rtf1 in Saccharomyces cerevisiae and rtfA in Aspergillus nidulans. Interestingly, rtfA has multiple cellular roles in this mycotoxin-producing fungus. In this study, we show that rtfA regulates conidiation. The rtfA deletion mutant presented smaller conidiophores with significantly reduced conidial production compared to the wild-type strain. The absence of rtfA also resulted in a significant decrease or lack of sclerotial production under conditions that allowed abundant production of these resistance structures in the wild type. Importantly, the deletion of rtfA notably reduced the production of aflatoxin B1, indicating that rtfA is a regulator of mycotoxin biosynthesis in A. flavus. In addition, the deletion rtfA also altered the production of several unknown secondary metabolites indicating a broader regulatory scope. Furthermore, our study revealed that rtfA controls the expression of the global regulators veA and laeA, which further influence morphogenesis and secondary metabolism in A. flavus.
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Zhuang Z, Lohmar JM, Satterlee T, Cary JW, Calvo AM. The Master Transcription Factor mtfA Governs Aflatoxin Production, Morphological Development and Pathogenicity in the Fungus Aspergillus flavus. Toxins (Basel) 2016; 8:toxins8010029. [PMID: 26805883 PMCID: PMC4728551 DOI: 10.3390/toxins8010029] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Revised: 12/23/2015] [Accepted: 01/06/2016] [Indexed: 11/30/2022] Open
Abstract
Aspergillus flavus produces a variety of toxic secondary metabolites; among them, the aflatoxins (AFs) are the most well known. These compounds are highly mutagenic and carcinogenic, particularly AFB1. A. flavus is capable of colonizing a number of economically-important crops, such as corn, cotton, peanut and tree nuts, and contaminating them with AFs. Molecular genetic studies in A. flavus could identify novel gene targets for use in strategies to reduce AF contamination and its adverse impact on food and feed supplies worldwide. In the current study, we investigated the role of the master transcription factor gene mtfA in A. flavus. Our results revealed that forced overexpression of mtfA results in a drastic decrease or elimination of several secondary metabolites, among them AFB1. The reduction in AFB1 was accompanied by a decrease in aflR expression. Furthermore, mtfA also regulates development; conidiation was influenced differently by this gene depending on the type of colonized substrate. In addition to its effect on conidiation, mtfA is necessary for the normal maturation of sclerotia. Importantly, mtfA positively affects the pathogenicity of A. flavus when colonizing peanut seeds. AF production in colonized seeds was decreased in the deletion mtfA strain and particularly in the overexpression strain, where only trace amounts were detected. Interestingly, a more rapid colonization of the seed tissue occurred when mtfA was overexpressed, coinciding with an increase in lipase activity and faster maceration of the oily part of the seed.
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Affiliation(s)
- Zhenhong Zhuang
- Department of Biological Sciences, Northern Illinois University, 155 Castle Dr., Dekalb, IL 60115, USA.
| | - Jessica M Lohmar
- Department of Biological Sciences, Northern Illinois University, 155 Castle Dr., Dekalb, IL 60115, USA.
| | - Timothy Satterlee
- Department of Biological Sciences, Northern Illinois University, 155 Castle Dr., Dekalb, IL 60115, USA.
| | - Jeffrey W Cary
- Food and Feed Safety Research Unit, USDA/ARS, Southern Regional Research Center, New Orleans, LA 70124, USA.
| | - Ana M Calvo
- Department of Biological Sciences, Northern Illinois University, 155 Castle Dr., Dekalb, IL 60115, USA.
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Frisvad JC, Larsen TO. Extrolites of Aspergillus fumigatus and Other Pathogenic Species in Aspergillus Section Fumigati. Front Microbiol 2016; 6:1485. [PMID: 26779142 PMCID: PMC4703822 DOI: 10.3389/fmicb.2015.01485] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Accepted: 12/09/2015] [Indexed: 11/13/2022] Open
Abstract
Aspergillus fumigatus is an important opportunistic human pathogen known for its production of a large array of extrolites. Up to 63 species have been described in Aspergillus section Fumigati, some of which have also been reliably reported to be pathogenic, including A. felis, A. fischeri, A. fumigatiaffinis, A. fumisynnematus, A. hiratsukae, A. laciniosus, A. lentulus, A. novofumigatus, A. parafelis, A. pseudofelis, A. pseudoviridinutans, A. spinosus, A. thermomutatus, and A. udagawae. These species share the production of hydrophobins, melanins, and siderophores and ability to grow well at 37°C, but they only share some small molecule extrolites, that could be important factors in pathogenicity. According to the literature gliotoxin and other exometabolites can be contributing factors to pathogenicity, but these exometabolites are apparently not produced by all pathogenic species. It is our hypothesis that species unable to produce some of these metabolites can produce proxy-exometabolites that may serve the same function. We tabulate all exometabolites reported from species in Aspergillus section Fumigati and by comparing the profile of those extrolites, suggest that those producing many different kinds of exometabolites are potential opportunistic pathogens. The exometabolite data also suggest that the profile of exometabolites are highly specific and can be used for identification of these closely related species.
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Affiliation(s)
- Jens C. Frisvad
- Section of Eukaryotic Biotechnology, Department of Systems Biology, Technical University of DenmarkKongens Lyngby, Denmark
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Scharf DH, Brakhage AA, Mukherjee PK. Gliotoxin--bane or boon? Environ Microbiol 2015; 18:1096-109. [PMID: 26443473 DOI: 10.1111/1462-2920.13080] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Revised: 09/30/2015] [Accepted: 10/04/2015] [Indexed: 12/31/2022]
Abstract
Gliotoxin (GT) is the most important epidithiodioxopiperazine (ETP)-type fungal toxin. GT was originally isolated from Trichoderma species as an antibiotic substance involved in biological control of plant pathogenic fungi. A few isolates of GT-producing Trichoderma virens are commercially marketed for biological control and widely used in agriculture. Furthermore, GT is long known as an immunosuppressive agent and also reported to have anti-tumour properties. However, recent publications suggest that GT is a virulence determinant of the human pathogen Aspergillus fumigatus. This compound is thus important on several counts - it has medicinal properties, is a pathogenicity determinant, is a potential diagnostic marker and is important in biological crop protection. The present article addresses this paradox and the ecological role of GT. We discuss the function of GT as defence molecule, the role in aspergillosis and suggest solutions for safe application of Trichoderma-based biofungicides.
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Affiliation(s)
- Daniel H Scharf
- Department of Molecular and Applied Microbiology, Leibniz-Institute for Natural Product Research and Infection Biology, Hans Knoell Institute (HKI) and Institute for Microbiology, Friedrich Schiller University Jena, Beutenbergstr. 11a, 07745, Jena, Germany
| | - Axel A Brakhage
- Department of Molecular and Applied Microbiology, Leibniz-Institute for Natural Product Research and Infection Biology, Hans Knoell Institute (HKI) and Institute for Microbiology, Friedrich Schiller University Jena, Beutenbergstr. 11a, 07745, Jena, Germany
| | - Prasun K Mukherjee
- Nuclear Agriculture and Biotechnology Division, Bhabha Atomic Research Centre, Trombay, Mumbai, 400085, India
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Tamiya H, Ochiai E, Kikuchi K, Yahiro M, Toyotome T, Watanabe A, Yaguchi T, Kamei K. Secondary metabolite profiles and antifungal drug susceptibility of Aspergillus fumigatus and closely related species, Aspergillus lentulus, Aspergillus udagawae, and Aspergillus viridinutans. J Infect Chemother 2015; 21:385-91. [PMID: 25737146 DOI: 10.1016/j.jiac.2015.01.005] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Revised: 01/05/2015] [Accepted: 01/13/2015] [Indexed: 11/20/2022]
Abstract
The incidence of Aspergillus infection has been increasing in the past few years. Also, new Aspergillus fumigatus-related species, namely Aspergillus lentulus, Aspergillus udagawae, and Aspergillus viridinutans, were shown to infect humans. These fungi exhibit marked morphological similarities to A. fumigatus, albeit with different clinical courses and antifungal drug susceptibilities. The present study used liquid chromatography/time-of-flight mass spectrometry to identify the secondary metabolites secreted as virulence factors by these Aspergillus species and compared their antifungal susceptibility. The metabolite profiles varied widely among A. fumigatus, A. lentulus, A. udagawae, and A. viridinutans, producing 27, 13, 8, and 11 substances, respectively. Among the mycotoxins, fumifungin, fumiquinazoline A/B and D, fumitremorgin B, gliotoxin, sphingofungins, pseurotins, and verruculogen were only found in A. fumigatus, whereas auranthine was only found in A. lentulus. The amount of gliotoxin, one of the most abundant mycotoxins in A. fumigatus, was negligible in these related species. In addition, they had decreased susceptibility to antifungal agents such as itraconazole and voriconazole, even though metabolites that were shared in the isolates showing higher minimum inhibitory concentrations than epidemiological cutoff values were not detected. These strikingly different secondary metabolite profiles may lead to the development of more discriminative identification protocols for such closely related Aspergillus species as well as improved treatment outcomes.
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Affiliation(s)
- Hiroyuki Tamiya
- Division of Fungal Infection, Medical Mycology Research Center, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8673, Japan; Department of Respiratory Medicine, The University of Tokyo Hospital, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan; Division of Clinical Research, Medical Mycology Research Center, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8677, Japan.
| | - Eri Ochiai
- Division of Fungal Infection, Medical Mycology Research Center, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8673, Japan
| | - Kazuyo Kikuchi
- Division of Bio-resources, Medical Mycology Research Center, Chiba University, Chiba, Japan
| | - Maki Yahiro
- Division of Fungal Infection, Medical Mycology Research Center, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8673, Japan
| | - Takahito Toyotome
- Division of Fungal Infection, Medical Mycology Research Center, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8673, Japan
| | - Akira Watanabe
- Division of Fungal Infection, Medical Mycology Research Center, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8673, Japan; Division of Clinical Research, Medical Mycology Research Center, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8677, Japan; Division of Control and Treatment of Infectious Diseases, Chiba University Hospital, 1-8-1 Inohana, Chuo-ku, Chiba 260-8677, Japan
| | - Takashi Yaguchi
- Division of Bio-resources, Medical Mycology Research Center, Chiba University, Chiba, Japan
| | - Katsuhiko Kamei
- Division of Fungal Infection, Medical Mycology Research Center, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8673, Japan; Division of Clinical Research, Medical Mycology Research Center, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8677, Japan; Division of Control and Treatment of Infectious Diseases, Chiba University Hospital, 1-8-1 Inohana, Chuo-ku, Chiba 260-8677, Japan
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Dogi C, Alonso V, Fochesato A, Poloni V, Cavaglieri L. Comparison of toxicogenic and immunosuppressive capacity of Aspergillus fumigatus
strains isolated from clinical and corn silage samples. J Appl Microbiol 2014; 118:175-81. [DOI: 10.1111/jam.12673] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Revised: 09/15/2014] [Accepted: 10/19/2014] [Indexed: 11/29/2022]
Affiliation(s)
- C. Dogi
- Departamento de Microbiología e Inmunología; Universidad Nacional de Río Cuarto; Río Cuarto Córdoba Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET); Buenos Aires Argentina
| | - V. Alonso
- Departamento de Microbiología e Inmunología; Universidad Nacional de Río Cuarto; Río Cuarto Córdoba Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET); Buenos Aires Argentina
| | - A. Fochesato
- Departamento de Microbiología e Inmunología; Universidad Nacional de Río Cuarto; Río Cuarto Córdoba Argentina
- Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET); Buenos Aires; Argentina
| | - V. Poloni
- Departamento de Microbiología e Inmunología; Universidad Nacional de Río Cuarto; Río Cuarto Córdoba Argentina
- Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET); Buenos Aires; Argentina
| | - L. Cavaglieri
- Departamento de Microbiología e Inmunología; Universidad Nacional de Río Cuarto; Río Cuarto Córdoba Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET); Buenos Aires Argentina
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Schoberle TJ, Nguyen-Coleman CK, Herold J, Yang A, Weirauch M, Hughes TR, McMurray JS, May GS. A novel C2H2 transcription factor that regulates gliA expression interdependently with GliZ in Aspergillus fumigatus. PLoS Genet 2014; 10:e1004336. [PMID: 24784729 PMCID: PMC4006717 DOI: 10.1371/journal.pgen.1004336] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2013] [Accepted: 03/13/2014] [Indexed: 12/30/2022] Open
Abstract
Secondary metabolites are produced by numerous organisms and can either be beneficial, benign, or harmful to humans. Genes involved in the synthesis and transport of these secondary metabolites are frequently found in gene clusters, which are often coordinately regulated, being almost exclusively dependent on transcription factors that are located within the clusters themselves. Gliotoxin, which is produced by a variety of Aspergillus species, Trichoderma species, and Penicillium species, exhibits immunosuppressive properties and has therefore been the subject of research for many laboratories. There have been a few proteins shown to regulate the gliotoxin cluster, most notably GliZ, a Zn2Cys6 binuclear finger transcription factor that lies within the cluster, and LaeA, a putative methyltransferase that globally regulates secondary metabolism clusters within numerous fungal species. Using a high-copy inducer screen in A. fumigatus, our lab has identified a novel C2H2 transcription factor, which plays an important role in regulating the gliotoxin biosynthetic cluster. This transcription factor, named GipA, induces gliotoxin production when present in extra copies. Furthermore, loss of gipA reduces gliotoxin production significantly. Through protein binding microarray and mutagenesis, we have identified a DNA binding site recognized by GipA that is in extremely close proximity to a potential GliZ DNA binding site in the 5' untranslated region of gliA, which encodes an efflux pump within the gliotoxin cluster. Not surprisingly, GliZ and GipA appear to work in an interdependent fashion to positively control gliA expression.
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Affiliation(s)
- Taylor J. Schoberle
- The University of Texas Graduate School of Biomedical Sciences at Houston, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
| | - C. Kim Nguyen-Coleman
- The University of Texas Graduate School of Biomedical Sciences at Houston, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
| | - Jennifer Herold
- The University of Texas Graduate School of Biomedical Sciences at Houston, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
- Microbiology and Molecular Genetics, Division of Pathology and Laboratory Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
| | - Ally Yang
- Banting and Best Department of Medical Research, Donnelly Centre, and Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Matt Weirauch
- Banting and Best Department of Medical Research, Donnelly Centre, and Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Timothy R. Hughes
- Banting and Best Department of Medical Research, Donnelly Centre, and Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - John S. McMurray
- The University of Texas Graduate School of Biomedical Sciences at Houston, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
- Department of Experimental Therapeutics, Division of Cancer Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
| | - Gregory S. May
- The University of Texas Graduate School of Biomedical Sciences at Houston, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
- Microbiology and Molecular Genetics, Division of Pathology and Laboratory Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
- Program in Genes and Development, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
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Robinet P, Baychelier F, Fontaine T, Picard C, Debré P, Vieillard V, Latgé JP, Elbim C. A polysaccharide virulence factor of a human fungal pathogen induces neutrophil apoptosis via NK cells. THE JOURNAL OF IMMUNOLOGY 2014; 192:5332-42. [PMID: 24790151 DOI: 10.4049/jimmunol.1303180] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Aspergillus fumigatus is an opportunistic human fungal pathogen that sheds galactosaminogalactan (GG) into the environment. Polymorphonuclear neutrophils (PMNs) and NK cells are both part of the first line of defense against pathogens. We recently reported that GG induces PMN apoptosis. In this study, we show that PMN apoptosis occurs via a new NK cell-dependent mechanism. Reactive oxygen species, induced by the presence of GG, play an indispensable role in this apoptotic effect by increasing MHC class I chain-related molecule A expression at the PMN surface. This increased expression enables interaction between MHC class I chain-related molecule A and NKG2D, leading to NK cell activation, which in turn generates a Fas-dependent apoptosis-promoting signal in PMNs. Taken together, our results demonstrate that the crosstalk between PMNs and NK cells is essential to GG-induced PMN apoptosis. NK cells might thus play a role in the induction of PMN apoptosis in situations such as unexplained neutropenia or autoimmune diseases.
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Affiliation(s)
- Pauline Robinet
- Université Pierre et Marie Curie Paris 06, Unité Mixte de Recherche-S CR7, Sorbonne Université, F-75005 Paris, France; INSERM, Centre d'Immunologie et des Maladies Infectieuses, Unité Mixte de Recherche-S CR7, INSERM U1135, F-75013 Paris, France
| | - Florence Baychelier
- INSERM, Centre d'Immunologie et des Maladies Infectieuses, Unité Mixte de Recherche-S CR7, INSERM U1135, F-75013 Paris, France
| | | | - Capucine Picard
- Centre D'étude des Déficits Immunitaires, Assistance Publique-Hôpitaux de Paris, L'hôpital Necker - Enfants Malades, 75743 Paris, France; Paris Descartes University, Sorbonne Paris Cité, 75006 Paris, France; Laboratory of Human Genetics of Infectious Diseases, Necker Branch, INSERM U980, Necker Medical School, 75015 Paris, France; and
| | - Patrice Debré
- Université Pierre et Marie Curie Paris 06, Unité Mixte de Recherche-S CR7, Sorbonne Université, F-75005 Paris, France; INSERM, Centre d'Immunologie et des Maladies Infectieuses, Unité Mixte de Recherche-S CR7, INSERM U1135, F-75013 Paris, France; Département d'Immunologie, Assistance Publique - Hôpitaux de Paris, Hôpital Pitié-Salpêtrière, 75013 Paris, France
| | - Vincent Vieillard
- INSERM, Centre d'Immunologie et des Maladies Infectieuses, Unité Mixte de Recherche-S CR7, INSERM U1135, F-75013 Paris, France
| | - Jean-Paul Latgé
- Institut Pasteur, Unité des Aspergillus, 75015 Paris, France
| | - Carole Elbim
- Université Pierre et Marie Curie Paris 06, Unité Mixte de Recherche-S CR7, Sorbonne Université, F-75005 Paris, France; INSERM, Centre d'Immunologie et des Maladies Infectieuses, Unité Mixte de Recherche-S CR7, INSERM U1135, F-75013 Paris, France;
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Eshwika A, Kelly J, Fallon JP, Kavanagh K. Exposure of Aspergillus fumigatus to caspofungin results in the release, and de novo biosynthesis, of gliotoxin. Med Mycol 2014; 51:121-7. [PMID: 23323804 DOI: 10.3109/13693786.2012.688180] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Caspofungin is a member of the echinocandin class of antifungal agents that inhibit the synthesis of β 1,3 glucan thus disrupting fungal cell wall structure and function. Exposure of the Aspergillus fumigatus cultures to caspofungin (0.01, 0.1 or 1.0 μg/ml) resulted in a reduction in cell growth, but the production of the epipolythiodioxopiperazine toxin, gliotoxin, was comparable, or greater, in cultures exposed to caspofungin than untreated controls. Exposure of A. fumigatus hyphae to 1.0 μg/ml caspofungin for 4 h resulted in the release of amino acids (P = 0.01), protein (P = 0.002) and gliotoxin (P = 0.02). Cultures of A. fumigatus incubated in the presence of caspofungin for 4 or 24 h demonstrated enhanced gliotoxin release (P = 0.04 and 0.03, respectively) and biosynthesis (P = 0.04 and 0.03, respectively) compared to that by control cultures. The results presented here indicate that exposure of A. fumigatus to caspofungin results in increased cell permeability and an increase in the synthesis and release of gliotoxin. Since gliotoxin has well established immunosuppressive properties it is possible that exposure of A. fumigatus to caspofungin may potentiate the production of this toxin at the site of infection. Elevated gliotoxin biosynthesis may be an attempt by the fungus to restore the redox balance of the cell following exposure to the antifungal agent but the overall effect appears to be enhanced synthesis and release.
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Affiliation(s)
- Ahmed Eshwika
- Medical Mycology Unit, National Institute for Cellular Biotechnology, Department of Biology, National University of Ireland Maynooth, Co. Kildare, Ireland
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The mtfA transcription factor gene controls morphogenesis, gliotoxin production, and virulence in the opportunistic human pathogen Aspergillus fumigatus. EUKARYOTIC CELL 2014; 13:766-75. [PMID: 24728192 DOI: 10.1128/ec.00075-14] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Aspergillus fumigatus is the leading causative agent of invasive aspergillosis (IA). The number of cases is on the rise, with mortality rates as high as 90% among immunocompromised patients. Molecular genetic studies in A. fumigatus could provide novel targets to potentially set the basis for antifungal therapies. In the current study, we investigated the role of the transcription factor gene mtfA in A. fumigatus. Our results revealed that mtfA plays a role in the growth and development of the fungus. Deletion or overexpression of mtfA leads to a slight reduction in colony growth, as well as a reduction in conidiation levels, in the overexpression strain compared to the wild-type strain. Furthermore, production of the secondary metabolite gliotoxin increased when mtfA was overexpressed, coinciding with an increase in the transcription levels of the gliotoxin genes gliZ and gliP with respect to the wild type. In addition, our study showed that mtfA is also necessary for normal protease activity in A. fumigatus; deletion of mtfA resulted in a reduction of protease activity compared to wild-type levels. Importantly, the absence of mtfA caused a decrease in virulence in the Galleria mellonella infection model, indicating that mtfA is necessary for A. fumigatus wild-type pathogenesis.
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Svahn KS, Göransson U, Chryssanthou E, Olsen B, Sjölin J, Strömstedt AA. Induction of gliotoxin secretion in Aspergillus fumigatus by bacteria-associated molecules. PLoS One 2014; 9:e93685. [PMID: 24705440 PMCID: PMC3976306 DOI: 10.1371/journal.pone.0093685] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Accepted: 03/09/2014] [Indexed: 11/29/2022] Open
Abstract
Aspergillus fumigatus is the most common causative agent of mold diseases in humans, giving rise to life-threatening infections in immunocompromised individuals. One of its secreted metabolites is gliotoxin, a toxic antimicrobial agent. The aim of this study was to determine whether the presence of pathogen-associated molecular patterns in broth cultures of A. fumigatus could induce gliotoxin production. Gliotoxin levels were analyzed by ultra-performance liquid chromatography and mass spectrometry. The presence of a bacteria-derived lipopolysaccharide, peptidoglycan, or lipoteichoic acid in the growth media at a concentration of 5 μg/ml increased the gliotoxin concentration in the media by 37%, 65%, and 35%, respectively. The findings reveal a correlation between the concentrations of pathogen-associated molecular patterns and gliotoxin secretion. This shows that there is a yet uncharacterized detection system for such compounds within fungi. Inducing secondary metabolite production by such means in fungi is potentially relevant for drug discovery research. Our results also give a possible explanation for the increased virulence of A. fumigatus during bacterial co-infection, one that is important for the transition from colonization to invasiveness in this pulmonary disease.
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Affiliation(s)
- K. Stefan Svahn
- Department of Medicinal Chemistry, Uppsala University, Uppsala, Sweden
| | - Ulf Göransson
- Department of Medicinal Chemistry, Uppsala University, Uppsala, Sweden
| | - Erja Chryssanthou
- Department of Clinical Microbiology, Karolinska University Hospital & Karolinska Institute, Stockholm, Sweden
| | - Björn Olsen
- Department of Medicinal Sciences, Uppsala University, Uppsala, Sweden
| | - Jan Sjölin
- Department of Medicinal Sciences, Uppsala University, Uppsala, Sweden
| | - Adam A. Strömstedt
- Department of Medicinal Chemistry, Uppsala University, Uppsala, Sweden
- * E-mail:
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Wang SX, Zhang XS, Guan HS, Wang W. Potential anti-HPV and related cancer agents from marine resources: an overview. Mar Drugs 2014; 12:2019-35. [PMID: 24705500 PMCID: PMC4012449 DOI: 10.3390/md12042019] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2014] [Revised: 03/10/2014] [Accepted: 03/14/2014] [Indexed: 12/14/2022] Open
Abstract
Recently, the studies on the prevention and treatment of human papillomavirus (HPV) which is closely related to the cervical cancer and other genital diseases are attracting more and more attention all over the world. Marine-derived polysaccharides and other bioactive compounds have been shown to possess a variety of anti-HPV and related cancer activities. This paper will review the recent progress in research on the potential anti-HPV and related cancer agents from marine resources. In particular, it will provide an update on the anti-HPV actions of heparinoid polysaccharides and bioactive compounds present in marine organisms, as well as the therapeutic vaccines relating to marine organisms. In addition, the possible mechanisms of anti-HPV actions of marine bioactive compounds and their potential for therapeutic application will also be summarized in detail.
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Affiliation(s)
- Shi-Xin Wang
- Key Laboratory of Marine Drugs, Ministry of Education, Ocean University of China, Qingdao 266003, China.
| | - Xiao-Shuang Zhang
- Key Laboratory of Marine Drugs, Ministry of Education, Ocean University of China, Qingdao 266003, China.
| | - Hua-Shi Guan
- Key Laboratory of Marine Drugs, Ministry of Education, Ocean University of China, Qingdao 266003, China.
| | - Wei Wang
- Key Laboratory of Marine Drugs, Ministry of Education, Ocean University of China, Qingdao 266003, China.
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Jia X, Chen F, Pan W, Yu R, Tian S, Han G, Fang H, Wang S, Zhao J, Li X, Zheng D, Tao S, Liao W, Han X, Han L. Gliotoxin promotes Aspergillus fumigatus internalization into type II human pneumocyte A549 cells by inducing host phospholipase D activation. Microbes Infect 2014; 16:491-501. [PMID: 24637030 DOI: 10.1016/j.micinf.2014.03.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Revised: 02/27/2014] [Accepted: 03/04/2014] [Indexed: 10/25/2022]
Abstract
The internalization of Aspergillus fumigatus into lung epithelial cells is critical for the infection process in the host. Gliotoxin is the most potent toxin produced by A. fumigatus. However, its role in A. fumigatus internalization into the lung epithelial cells is still largely unknown. In the present study, the deletion of the gliP gene regulating the production of gliotoxin in A. fumigatus suppressed the internalization of conidia into the A549 lung epithelial cells, and this suppression could be rescued by the exogenous addition of gliotoxin. At lower concentrations, gliotoxin enhanced the internalization of the conidia of A. fumigatus into A549 cells; in contrast, it inhibited the phagocytosis of J774 macrophages in a dose-dependent manner. Under a concentration of 100 ng/ml, gliotoxin had no effect on A549 cell viability but attenuated ROS production in a dose-dependent manner. Gliotoxin significantly stimulated the phospholipase D activity in the A549 cells at a concentration of 50 ng/ml. This stimulation was blocked by the pretreatment of host cells with PLD1- but not PLD2-specific inhibitor. Morphological cell changes induced by gliotoxin were observed in the A549 cells accompanying with obvious actin cytoskeleton rearrangement and a moderate alteration of phospholipase D distribution. Our data indicated that gliotoxin might be responsible for modulating the A. fumigatus internalization into epithelial cells through phospholipase D1 activation and actin cytoskeleton rearrangement.
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Affiliation(s)
- Xiaodong Jia
- Department for Hospital Infection Control & Research, Institute of Disease Control & Prevention of PLA, Academy of Military Medical Sciences, Beijing, China
| | - Fangyan Chen
- Department for Hospital Infection Control & Research, Institute of Disease Control & Prevention of PLA, Academy of Military Medical Sciences, Beijing, China
| | - Weihua Pan
- Shanghai Key Laboratory of Molecular Mycology, Department of Dermatology, Shanghai Changzheng Hospital, Second Military Medical University, Shanghai, China
| | - Rentao Yu
- Department for Hospital Infection Control & Research, Institute of Disease Control & Prevention of PLA, Academy of Military Medical Sciences, Beijing, China; Patent Examination Cooperation Center of the Patent Office, Beijing, China
| | - Shuguang Tian
- Department for Hospital Infection Control & Research, Institute of Disease Control & Prevention of PLA, Academy of Military Medical Sciences, Beijing, China
| | - Gaige Han
- Department for Hospital Infection Control & Research, Institute of Disease Control & Prevention of PLA, Academy of Military Medical Sciences, Beijing, China
| | - Haiqin Fang
- Department for Hospital Infection Control & Research, Institute of Disease Control & Prevention of PLA, Academy of Military Medical Sciences, Beijing, China
| | - Shuo Wang
- Department for Hospital Infection Control & Research, Institute of Disease Control & Prevention of PLA, Academy of Military Medical Sciences, Beijing, China
| | - Jingya Zhao
- Department for Hospital Infection Control & Research, Institute of Disease Control & Prevention of PLA, Academy of Military Medical Sciences, Beijing, China
| | - Xianping Li
- Department for Hospital Infection Control & Research, Institute of Disease Control & Prevention of PLA, Academy of Military Medical Sciences, Beijing, China
| | - Dongyu Zheng
- Department for Hospital Infection Control & Research, Institute of Disease Control & Prevention of PLA, Academy of Military Medical Sciences, Beijing, China
| | - Sha Tao
- Department for Hospital Infection Control & Research, Institute of Disease Control & Prevention of PLA, Academy of Military Medical Sciences, Beijing, China
| | - Wanqing Liao
- Shanghai Key Laboratory of Molecular Mycology, Department of Dermatology, Shanghai Changzheng Hospital, Second Military Medical University, Shanghai, China
| | - Xuelin Han
- Department for Hospital Infection Control & Research, Institute of Disease Control & Prevention of PLA, Academy of Military Medical Sciences, Beijing, China.
| | - Li Han
- Department for Hospital Infection Control & Research, Institute of Disease Control & Prevention of PLA, Academy of Military Medical Sciences, Beijing, China.
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Nguyen VT, Lee JS, Qian ZJ, Li YX, Kim KN, Heo SJ, Jeon YJ, Park WS, Choi IW, Je JY, Jung WK. Gliotoxin isolated from marine fungus Aspergillus sp. induces apoptosis of human cervical cancer and chondrosarcoma cells. Mar Drugs 2013; 12:69-87. [PMID: 24368570 PMCID: PMC3917261 DOI: 10.3390/md12010069] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Revised: 12/09/2013] [Accepted: 12/11/2013] [Indexed: 12/19/2022] Open
Abstract
Gliotoxin, a secondary metabolite produced by marine fungus Aspergillus sp., possesses various biological activities including anticancer activity. However, the mechanism underlying gliotoxin-induced cytotoxicity on human cervical cancer (Hela) and human chondrosarcoma (SW1353) cells remains unclear. In this study, we focused on the effect of gliotoxin induction on apoptosis, the activating expressions of caspase family enzymes in the cells. Apoptotic cell levels were measured through DAPI and Annexin V/Propidium Iodide (PI) double staining analysis. The apoptotic protein expression of Bcl-2 and caspase family was detected by Western blot in Hela and SW1353 cells. Our results showed that gliotoxin treatment inhibited cell proliferation and induced significant morphological changes. Gliotoxin induced apoptosis was further confirmed by DNA fragmentation, chromatin condensation and disrupted mitochondrial membrane potential. Gliotoxin-induced activation of caspase-3, caspase-8 and caspase-9, down-regulation of Bcl-2, up-regulation of Bax and cytochromec (cyt c) release showed evidence for the gliotoxin activity on apoptosis. These findings suggest that gliotoxin isolated from marine fungus Aspergillus sp. induced apoptosis in Hela and SW1353 cells via the mitochondrial pathway followed by downstream events leading to apoptotic mode of cell death.
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Affiliation(s)
- Van-Tinh Nguyen
- Department of Biomedical Engineering, and Centre for Marine-Integrated Biomedical Technology (BK21 Plus) Pukyong National University, Busan 608-737, Korea; E-Mail:
| | - Jung Suck Lee
- Industry-Academic Cooperation Foundation, Jeju National University, Jeju 690-756, Korea; E-Mail:
| | - Zhong-Ji Qian
- College of Food Science and Technology, Guangdong Ocean University, Zhanjiang 524088, China; E-Mail:
| | - Yong-Xin Li
- Marine Bioprocess Research Center, Pukyong National University, Busan 608-737, Korea; E-Mail:
| | - Kil-Nam Kim
- Marine Bio Research Team, Korea Basic Science Institute (KBSI), Jeju 690-140, Korea; E-Mail:
| | - Soo-Jin Heo
- Global Bioresources Research Center, Korea Institute of Ocean Science & Technology, Ansan 426-744, Korea; E-Mail:
| | - You-Jin Jeon
- Department of Marine Life Sciences, Jeju National University, Jeju 690-756, Korea; E-Mail:
| | - Won Sun Park
- Department of Physiology, Kangwon National University School of Medicine, Chuncheon 200-701, Korea; E-Mail:
| | - Il-Whan Choi
- Department of Microbiology, College of Medicine, Inje University, Busan 608-737, Korea; E-Mail:
| | - Jae-Young Je
- Department of Marine Bio-Food Sciences, Chonnam National University, Yeosu 550-749, Korea
- Authors to whom correspondence should be addressed; E-Mails: (J.-Y.J.); (W.-K.J.); Tel.: +82-61-659-7416 (J.-Y.J.); Fax: +82-61-659-7419 (J.-Y.J.); Tel./Fax: +82-51-629-5775 (W.-K.J.)
| | - Won-Kyo Jung
- Department of Biomedical Engineering, and Centre for Marine-Integrated Biomedical Technology (BK21 Plus) Pukyong National University, Busan 608-737, Korea; E-Mail:
- Authors to whom correspondence should be addressed; E-Mails: (J.-Y.J.); (W.-K.J.); Tel.: +82-61-659-7416 (J.-Y.J.); Fax: +82-61-659-7419 (J.-Y.J.); Tel./Fax: +82-51-629-5775 (W.-K.J.)
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Dhingra S, Lind AL, Lin HC, Tang Y, Rokas A, Calvo AM. The fumagillin gene cluster, an example of hundreds of genes under veA control in Aspergillus fumigatus. PLoS One 2013; 8:e77147. [PMID: 24116213 PMCID: PMC3792039 DOI: 10.1371/journal.pone.0077147] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Accepted: 08/25/2013] [Indexed: 01/24/2023] Open
Abstract
Aspergillus fumigatus is the causative agent of invasive aspergillosis, leading to infection-related mortality in immunocompromised patients. We previously showed that the conserved and unique-to-fungi veA gene affects different cell processes such as morphological development, gliotoxin biosynthesis and protease activity, suggesting a global regulatory effect on the genome of this medically relevant fungus. In this study, RNA sequencing analysis revealed that veA controls the expression of hundreds of genes in A. fumigatus, including those comprising more than a dozen known secondary metabolite gene clusters. Chemical analysis confirmed that veA controls the synthesis of other secondary metabolites in this organism in addition to gliotoxin. Among the secondary metabolite gene clusters regulated by veA is the elusive but recently identified gene cluster responsible for the biosynthesis of fumagillin, a meroterpenoid known for its anti-angiogenic activity by binding to human methionine aminopeptidase 2. The fumagillin gene cluster contains a veA-dependent regulatory gene, fumR (Afu8g00420), encoding a putative C6 type transcription factor. Deletion of fumR results in silencing of the gene cluster and elimination of fumagillin biosynthesis. We found expression of fumR to also be dependent on laeA, a gene encoding another component of the fungal velvet complex. The results in this study argue that veA is a global regulator of secondary metabolism in A. fumigatus, and that veA may be a conduit via which chemical development is coupled to morphological development and other cellular processes.
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Affiliation(s)
- Sourabh Dhingra
- Department of Biological Sciences, Northern Illinois University, DeKalb, Illinois, United States of America
| | - Abigail L. Lind
- Department of Biomedical Informatics, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Hsiao-Ching Lin
- Department of Chemical and Biomolecular Engineering, University of California Los Angeles, Los Angeles, California, United States of America
| | - Yi Tang
- Department of Chemical and Biomolecular Engineering, University of California Los Angeles, Los Angeles, California, United States of America
- Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, California, United States of America
| | - Antonis Rokas
- Department of Biomedical Informatics, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Ana M. Calvo
- Department of Biological Sciences, Northern Illinois University, DeKalb, Illinois, United States of America
- * E-mail:
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40
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Browne N, Heelan M, Kavanagh K. An analysis of the structural and functional similarities of insect hemocytes and mammalian phagocytes. Virulence 2013; 4:597-603. [PMID: 23921374 PMCID: PMC3906293 DOI: 10.4161/viru.25906] [Citation(s) in RCA: 211] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Revised: 07/24/2013] [Accepted: 07/25/2013] [Indexed: 11/29/2022] Open
Abstract
The insect immune response demonstrates a number of structural and functional similarities to the innate immune system of mammals. As a result of these conserved features insects have become popular choices for evaluating the virulence of microbial pathogens or for assessing the efficacy of antimicrobial agents and give results which are comparable to those that can be obtained using mammals. Analysis of the cellular component of the insect and mammalian immune systems demonstrates many similarities. Insect hemocytes recognize pathogens and phagocytose material in a similar manner to neutrophils. The killing of ingested microbes is achieved in both cell types by the production of superoxide and by the release of enzymes in the process of degranulation. Insect hemocytes and mammalian neutrophils are sensitive to the same inhibitors. This review highlights the strong similarities between the phagocytic cells of both groups of animals and demonstrates the potential benefits of using selected insects as in vivo screening systems.
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Affiliation(s)
- Niall Browne
- Department of Biology; NUI Maynooth; Maynooth, Co. Kildare Ireland
| | - Michelle Heelan
- Department of Biology; NUI Maynooth; Maynooth, Co. Kildare Ireland
| | - Kevin Kavanagh
- Department of Biology; NUI Maynooth; Maynooth, Co. Kildare Ireland
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41
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NADPH oxidase as a therapeutic target for oxalate induced injury in kidneys. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2013; 2013:462361. [PMID: 23840917 PMCID: PMC3690252 DOI: 10.1155/2013/462361] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/09/2013] [Accepted: 05/14/2013] [Indexed: 02/07/2023]
Abstract
A major role of the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase family of enzymes is to catalyze the production of superoxides and other reactive oxygen species (ROS). These ROS, in turn, play a key role as messengers in cell signal transduction and cell cycling, but when they are produced in excess they can lead to oxidative stress (OS). Oxidative stress in the kidneys is now considered a major cause of renal injury and inflammation, giving rise to a variety of pathological disorders. In this review, we discuss the putative role of oxalate in producing oxidative stress via the production of reactive oxygen species by isoforms of NADPH oxidases expressed in different cellular locations of the kidneys. Most renal cells produce ROS, and recent data indicate a direct correlation between upregulated gene expressions of NADPH oxidase, ROS, and inflammation. Renal tissue expression of multiple NADPH oxidase isoforms most likely will impact the future use of different antioxidants and NADPH oxidase inhibitors to minimize OS and renal tissue injury in hyperoxaluria-induced kidney stone disease.
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42
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Palmer JM, Bok JW, Lee S, Dagenais TRT, Andes DR, Kontoyiannis DP, Keller NP. Loss of CclA, required for histone 3 lysine 4 methylation, decreases growth but increases secondary metabolite production in Aspergillus fumigatus. PeerJ 2013; 1:e4. [PMID: 23638376 PMCID: PMC3629006 DOI: 10.7717/peerj.4] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2012] [Accepted: 12/04/2012] [Indexed: 12/13/2022] Open
Abstract
Secondary metabolite (SM) production in filamentous fungi is mechanistically associated with chromatin remodeling of specific SM clusters. One locus recently shown to be involved in SM suppression in Aspergillus nidulans was CclA, a member of the histone 3 lysine 4 methylating COMPASS complex. Here we examine loss of CclA and a putative H3K4 demethylase, HdmA, in the human pathogen Aspergillus fumigatus. Although deletion of hdmA showed no phenotype under the conditions tested, the cclA deletant was deficient in tri- and di-methylation of H3K4 and yielded a slowly growing strain that was rich in the production of several SMs, including gliotoxin. Similar to deletion of other chromatin modifying enzymes, ΔcclA was sensitive to 6-azauracil indicating a defect in transcriptional elongation. Despite the poor growth, the ΔcclA mutant had wild-type pathogenicity in a murine model and the Toll-deficient Drosophila model of invasive aspergillosis. These data indicate that tri- and di-methylation of H3K4 is involved in the regulation of several secondary metabolites in A. fumigatus, however does not contribute to pathogenicity under the conditions tested.
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Affiliation(s)
- Jonathan M Palmer
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI, USA
| | - Jin Woo Bok
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI, USA
| | - Seul Lee
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI, USA
| | - Taylor R T Dagenais
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI, USA
| | - David R Andes
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI, USA
| | - Dimitrios P Kontoyiannis
- Department of Infectious Disease, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Nancy P Keller
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI, USA.,Department of Bacteriology, University of Wisconsin-Madison, Madison, WI, USA
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43
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Malekinejad H, Fani F, Shafie-Irannejad V, Fink-Gremmel F. Aspergillus fumigatus toxins cause cytotoxic and apoptotic effects on human T lymphocytes (Jurkat cells). WORLD MYCOTOXIN J 2013. [DOI: 10.3920/wmj2012.1481] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Aspergillus fumigatus is a ubiquitous fungus, which plays a prominent role in the incidence of various diseases including invasive aspergillosis. The cytotoxicity and apoptotic effects of the main secondary metabolites of Aspergillus fumigatus including gliotoxin, kojic acid, fumagillin, and verruculogen were studied on human T lymphocytes (Jurkat cells). The calculated IC50 values, which were obtained based on the Alamar Blue reduction assay, indicated that the strongest toxicity was exerted by gliotoxin, followed by kojic acid and equally by fumagillin and verruculogen. Correspondingly, the evaluation of reactive oxygen species (ROS) production by the selected mycotoxins showed that gliotoxin exposure resulted in the highest ROS generation, followed by kojic acid, fumagillin and verruculogen. Each of the four mycotoxins exhibited concentration- and time-dependent apoptotic effects albeit with differences as evidenced by cytochrome C release, caspase-3/7 activity enhancement, and DNA fragmentation. In conclusion, a comparison of gliotoxin and other metabolites of A. fumigatus such as kojic acid, fumagillin and verruculogen identified gliotoxin as the most cytotoxic mycotoxin for Jurkat cells. As Jurkat cells represent human T lymphocytes, A. fumigatus toxins might exert significant immunosuppressive effects.
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Affiliation(s)
- H. Malekinejad
- Department of Veterinary Pharmacology and Toxicology, Faculty of Veterinary Medicine, Urmia University, P.O. Box 1177, Urmia, Iran
| | - F. Fani
- Department of Veterinary Pharmacology and Toxicology, Faculty of Veterinary Medicine, Urmia University, P.O. Box 1177, Urmia, Iran
| | - V. Shafie-Irannejad
- Department of Veterinary Pharmacology and Toxicology, Faculty of Veterinary Medicine, Urmia University, P.O. Box 1177, Urmia, Iran
| | - F. Fink-Gremmel
- Department of Veterinary Pharmacology, Pharmacy and Toxicology, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 104, 3508 TD Utrecht, the Netherlands
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44
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Morton CO, Bouzani M, Loeffler J, Rogers TR. Direct interaction studies between Aspergillus fumigatus and human immune cells; what have we learned about pathogenicity and host immunity? Front Microbiol 2012; 3:413. [PMID: 23264771 PMCID: PMC3525292 DOI: 10.3389/fmicb.2012.00413] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2012] [Accepted: 11/15/2012] [Indexed: 12/24/2022] Open
Abstract
Invasive aspergillosis is a significant threat to health and is a major cause of mortality in immunocompromised individuals. Understanding the interaction between the fungus and the immune system is important in determining how the immunocompetent host remains disease free. Several studies examining the direct interaction between Aspergillus fumigatus and purified innate immune cells have been conducted to measure the responses of both the host cells and the pathogen. It has been revealed that innate immune cells have different modes of action ranging from effective fungal killing by neutrophils to the less aggressive response of dendritic cells. Natural killer cells do not phagocytose the fungus unlike the other innate immune cells mentioned but appear to mediate their antifungal effect through the release of gamma interferon. Transcriptional analysis of A. fumigatus interacting with these cells has indicated that it can adapt to the harsh microenvironment of the phagosome and produces toxins, ribotoxin and gliotoxin, that can induce cell death in the majority of innate immune cells. These data point toward potential novel antifungal treatments including the use of innate immune cells as antifungal vaccines.
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Affiliation(s)
- Charles O Morton
- School of Science and Health, University of Western Sydney Campbelltown, NSW, Australia
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45
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VeA regulates conidiation, gliotoxin production, and protease activity in the opportunistic human pathogen Aspergillus fumigatus. EUKARYOTIC CELL 2012; 11:1531-43. [PMID: 23087369 DOI: 10.1128/ec.00222-12] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Invasive aspergillosis by Aspergillus fumigatus is a leading cause of infection-related mortality in immunocompromised patients. In this study, we show that veA, a major conserved regulatory gene that is unique to fungi, is necessary for normal morphogenesis in this medically relevant fungus. Although deletion of veA results in a strain with reduced conidiation, overexpression of this gene further reduced conidial production, indicating that veA has a major role as a regulator of development in A. fumigatus and that normal conidiation is only sustained in the presence of wild-type VeA levels. Furthermore, our studies revealed that veA is a positive regulator in the production of gliotoxin, a secondary metabolite known to be a virulent factor in A. fumigatus. Deletion of veA resulted in a reduction of gliotoxin production with respect to that of the wild-type control. This reduction in toxin coincided with a decrease in gliZ and gliP expression, which is necessary for gliotoxin biosynthesis. Interestingly, veA also influences protease activity in this organism. Specifically, deletion of veA resulted in a reduction of protease activity; this is the first report of a veA homolog with a role in controlling fungal hydrolytic activity. Although veA affects several cellular processes in A. fumigatus, pathogenicity studies in a neutropenic mouse infection model indicated that veA is dispensable for virulence.
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46
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The NADPH oxidase family and its inhibitors. Arch Immunol Ther Exp (Warsz) 2012; 60:277-94. [PMID: 22696046 DOI: 10.1007/s00005-012-0176-z] [Citation(s) in RCA: 90] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2011] [Accepted: 03/27/2012] [Indexed: 12/16/2022]
Abstract
The classical nicotinamide adenine dinucleotide phosphate (NADPH) oxidase was originally detected in neutrophils as a multicomponent enzyme that catalyzes the generation of superoxide from oxygen and the reduced form of NADPH. This enzyme is composed of two membrane-bound subunits (p22phox and gp91phox), three cytosolic subunits (p67phox, p47phox, and p40phox) and a small G-protein Rac (Rac1 and Rac2). Recently, it has been demonstrated that there are several isoforms of nonphagocytic NADPH oxidase. Endothelial cells, vascular smooth muscle cells or adventitial fibroblasts possess multiple isoforms of this enzyme. The new homologs, along with gp91phox are now designated the Nox family of NADPH oxidases and are key sources of reactive oxygen species in the vasculature. Reactive oxygen species play a significant role in regulating endothelial function and vascular tone. However, besides the participation in the processes of physiological cell, these enzymes can also be the perpetrator of oxidative stress that causes endothelial dysfunction. This review summarizes the current state of knowledge of the structure and functions of NADPH oxidase and NADPH oxidase inhibitors in the treatment of disorders with endothelial damage.
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47
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Banville N, Fallon J, McLoughlin K, Kavanagh K. Disruption of haemocyte function by exposure to cytochalasin b or nocodazole increases the susceptibility of Galleria mellonella larvae to infection. Microbes Infect 2011; 13:1191-8. [PMID: 21782965 DOI: 10.1016/j.micinf.2011.07.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2011] [Revised: 07/01/2011] [Accepted: 07/01/2011] [Indexed: 11/18/2022]
Abstract
Administration of non-toxic concentrations (10 μM) of cytochalasin b and nocodazole to larvae of Galleria mellonella increased their susceptibility to infection by the yeast Candida albicans. These agents were found to inhibit the process of phagocytosis and to reduce the killing ability of haemocytes. In addition, both cytochalasin b and nocodazole reduced the release of antimicrobial peptides (e.g. apolipophorin 3) and enzymes (e.g. serine protease) from PMA stimulated haemocytes. Rhodamine coupled phalloidin staining revealed reduced F-actin formation in haemocytes treated with nocodazole or cytochalasin b. By disrupting the formation of F-actin cytochalasin b and nocodazole have the ability to retard the function of haemocytes, in the same manner as they affect mammalian neutrophils, and thus increase the susceptibility of larvae to infection. The results presented here demonstrate that haemocytes are sensitive to inhibition by nocodazole and cytochalasin b, in a similar manner to neutrophils, thus highlighting another similarity between both cell types and so increasing the attractiveness of using insects as alternative models to the use of mammals for in vivo pathogen or drug screening.
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Affiliation(s)
- Nessa Banville
- Medical Mycology Unit, Department of Biology, NUI Maynooth, Co. Kildare, Ireland
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48
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Hasenberg M, Behnsen J, Krappmann S, Brakhage A, Gunzer M. Phagocyte responses towards Aspergillus fumigatus. Int J Med Microbiol 2011; 301:436-44. [PMID: 21571589 DOI: 10.1016/j.ijmm.2011.04.012] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
The saprophytic fungus Aspergillus fumigatus is a mold which is ubiquitously present in the environment. It produces large numbers of spores, called conidia that we constantly inhale with the breathing air. Healthy individuals normally do not suffer from true fungal infections with this pathogen. A normally robust resistance against Aspergillus is based on the presence of a very effective immunological defense system in the vertebrate body. Inhaled conidia are first encountered by lung-resident alveolar macrophages and then by neutrophil granulocytes. Both cell types are able to effectively ingest and destroy the fungus. Although some responses of the adaptive immune system develop, the key protection is mediated by innate immunity. The importance of phagocytes for defense against aspergillosis is also supported by large numbers of animal studies. Despite the production of aggressive chemicals that can extracellularly destroy fungal pathogens, the main effector mechanism of the innate immune system is phagocytosis. Very recently, the production of extracellular neutrophil extracellular traps (NETs) consisting of nuclear DNA has been added to the armamentarium that innate immune cells use against infection with Aspergillus. Phagocyte responses to Aspergillus are very broad, and a number of new observations have added to this complexity in recent years. To summarize established and newer findings, we will give an overview on current knowledge of the phagocyte system for the protection against Aspergillus.
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Affiliation(s)
- Mike Hasenberg
- Otto-von-Guericke University Magdeburg, Institute for Molecular and Clinical Immunology, Leipziger Str. 44, 39120 Magdeburg, Germany.
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49
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Lionakis MS, Kontoyiannis DP. The growing promise of Toll-deficient Drosophila melanogaster as a model for studying Aspergillus pathogenesis and treatment. Virulence 2010; 1:488-99. [PMID: 21178494 DOI: 10.4161/viru.1.6.13311] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Despite considerable progress over recent years, the prognosis of invasive aspergillosis (IA) remains unfavorable, reflecting an incomplete understanding of Aspergillus pathogenesis and suboptimal antifungal efficacy in vivo. Mammalian host systems including rodents and rabbits are important tools in elucidating antifungal drug activity and the immunopathogenesis of IA. Nonetheless, they are hampered by limitations that impose a "bottleneck" in mass screening of novel antifungal compounds and putative Aspergillus virulence factors including their cost, labor intensity and ethical constraints. Drosophila melanogaster is an invertebrate host with a long tract record of genetic studies and a simple, yet highly conserved innate immune system. Herein, we describe our experience using this fly model as a facile, non-laborious, inexpensive pathosystem for high-throughput screening of novel antifungal compounds and putative Aspergillus mutants, and studying antifungal innate immunity. We present three infection protocols (i.e., injection, rolling, ingestion) that introduce Aspergillus either directly into the hemolymph or at different epithelial surfaces of Toll-deficient Drosophila flies. As a proof of principle, we demonstrate attenuated virulence of known hypovirulent Aspergillus strains and protection of Aspergillus-infected flies given oral Aspergillus-active agents such is voriconazole. These protocols can be adapted for similar studies of other fungal pathogens. Crossing and generation of Toll-deficient Drosophila flies takes 3 weeks; Aspergillus conidial preparation takes 3 days; fly inoculation depending on the infection assay takes 1 to 6-8 hours; and assessment of fly survival, Aspergillus strain virulence, Drosophila innate host parameters and/or drug activity takes 4-8 days.
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Affiliation(s)
- Michail S Lionakis
- Laboratory of Molecular Immunology, National Institutes of Health, Bethesda, MD, USA
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Schrettl M, Ibrahim-Granet O, Droin S, Huerre M, Latgé JP, Haas H. The crucial role of the Aspergillus fumigatus siderophore system in interaction with alveolar macrophages. Microbes Infect 2010; 12:1035-41. [PMID: 20659583 PMCID: PMC2977081 DOI: 10.1016/j.micinf.2010.07.005] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2010] [Revised: 05/31/2010] [Accepted: 07/08/2010] [Indexed: 01/10/2023]
Abstract
Iron plays a central role in manifestation of infections for a variety of pathogens. To ensure an adequate supply with iron, Aspergillus fumigatus employs extra- and intracellular siderophores (low-molecular mass iron chelators), which are of importance for fungal growth in particular during iron starvation. Here we show that the lack of extracellular siderophores, and especially, the lack of the entire siderophore system cause in immunosuppressed mice in vivo (i) a reduced extracellular growth rate, (ii) a reduced intracellular growth rate in alveolar macrophages, and (iii) an increased susceptibility to conidial growth inhibition by alveolar macrophages. These data underline the crucial role of the fungal siderophore system not only for extracellular growth but also in the interaction with the host immune cells. Moreover, the hyphal growth rate within alveolar macrophages compared to extracellular lavage fluid was significantly decreased indicating that, besides elimination of fungal conidia, inhibition of pathogenic growth is a function of macrophages.
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Affiliation(s)
- Markus Schrettl
- Division of Molecular Biology/Biocenter, Innsbruck Medical University, Fritz-Pregl-Str. 3, 6020 Innsbruck, Austria
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