1
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Sonnberger J, Kasper L, Lange T, Brunke S, Hube B. "We've got to get out"-Strategies of human pathogenic fungi to escape from phagocytes. Mol Microbiol 2024; 121:341-358. [PMID: 37800630 DOI: 10.1111/mmi.15149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 08/08/2023] [Accepted: 08/16/2023] [Indexed: 10/07/2023]
Abstract
Human fungal pathogens are a deadly and underappreciated risk to global health that most severely affect immunocompromised individuals. A virulence attribute shared by some of the most clinically relevant fungal species is their ability to survive inside macrophages and escape from these immune cells. In this review, we discuss the mechanisms behind intracellular survival and elaborate how escape is mediated by lytic and non-lytic pathways as well as strategies to induce programmed host cell death. We also discuss persistence as an alternative to rapid host cell exit. In the end, we address the consequences of fungal escape for the host immune response and provide future perspectives for research and development of targeted therapies.
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Affiliation(s)
- Johannes Sonnberger
- Department of Microbial Pathogenicity Mechanisms, Hans Knoell Institute, Jena, Germany
| | - Lydia Kasper
- Department of Microbial Pathogenicity Mechanisms, Hans Knoell Institute, Jena, Germany
| | - Theresa Lange
- Department of Microbial Pathogenicity Mechanisms, Hans Knoell Institute, Jena, Germany
| | - Sascha Brunke
- Department of Microbial Pathogenicity Mechanisms, Hans Knoell Institute, Jena, Germany
| | - Bernhard Hube
- Department of Microbial Pathogenicity Mechanisms, Hans Knoell Institute, Jena, Germany
- Institute of Microbiology, Friedrich Schiller University, Jena, Germany
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2
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Thakur R, Shishodia SK, Sharma A, Chauhan A, Kaur S, Shankar J. Accelerating the understanding of Aspergillus terreus: Epidemiology, physiology, immunology and advances. CURRENT RESEARCH IN MICROBIAL SCIENCES 2024; 6:100220. [PMID: 38303967 PMCID: PMC10831165 DOI: 10.1016/j.crmicr.2024.100220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2024] Open
Abstract
Aspergillus species encompass a variety of infections, ranging from invasive aspergillosis to allergic conditions, contingent upon the immune status of the host. In this spectrum, Aspergillus terreus stands out due to its emergence as a notable pathogen and its intrinsic resistance to amphotericin-B. The significance of Aspergillus-associated infections has witnessed a marked increase in the past few decades, particularly with the increasing number of immunocompromised individuals. The exploration of epidemiology, morphological transitions, immunopathology, and novel treatment approaches such as new antifungal drugs (PC945, olorofim) and combinational therapy using antifungal drugs and phytochemicals (Phytochemicals: quercetin, shikonin, artemisinin), also using immunotherapies to modulate immune response has resulted in better outcomes. Furthermore, in the context COVID-19 era and its aftermath, fungal infections have emerged as a substantial challenge for both immunocompromised and immunocompetent individuals. This is attributed to the use of immune-suppressing therapies during COVID-19 infections and the increase in transplant cases. Consequently, this review aims to provide an updated overview encompassing the epidemiology, germination events, immunopathology, and novel drug treatment strategies against Aspergillus terreus-associated infections.
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Affiliation(s)
- Raman Thakur
- Department of Medical Laboratory Science, Lovely Professional University, Jalandhar, Punjab, India
| | | | - Ananya Sharma
- Genomic Laboratory, Department of Biotechnology and Bioinformatics, Jaypee University of Information Technology, Waknaghat Solan, Himachal Pradesh, India
| | - Arjun Chauhan
- Department of Biotechnology, Institute of Applied Sciences and Humanities, GLA University, Mathura, Uttar Pradesh, India
| | - Sumanpreet Kaur
- Department of Medical Laboratory Science, Lovely Professional University, Jalandhar, Punjab, India
| | - Jata Shankar
- Genomic Laboratory, Department of Biotechnology and Bioinformatics, Jaypee University of Information Technology, Waknaghat Solan, Himachal Pradesh, India
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3
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Hatinguais R, Leaves I, Brown GD, Brown AJP, Brock M, Peres da Silva R. CRISPR-based tools for targeted genetic manipulation in pathogenic Sporothrix species. Microbiol Spectr 2023; 11:e0507822. [PMID: 37707447 PMCID: PMC10581184 DOI: 10.1128/spectrum.05078-22] [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: 12/15/2022] [Accepted: 07/11/2023] [Indexed: 09/15/2023] Open
Abstract
Sporothrix brasiliensis is an emerging fungal pathogen frequently associated with zoonotic transmission of sporotrichosis by contaminated cats. Within 25 years, the disease has spread not only throughout Brazil but now to neighboring countries in Latin America. Thermo-dimorphism, melanin, glycans, adhesins, and secreted vesicles have been associated with the ability of Sporothrix species to cause disease in the mammalian host. Although certain virulence factors have been proposed as potential determinants for sporotrichosis, the scarcity of molecular tools for performing reverse genetics in Sporothrix has significantly impeded the dissection of mechanisms underlying the disease. Here, we demonstrate that PEG-mediated protoplast transformation is a powerful method for heterologous gene expression in S. brasiliensis, S. schenckii, and S. chilensis. Combined with CRISPR/Cas9 gene editing, this transformation protocol enabled the deletion of the putative DHN-melanin synthase gene pks1, which is a proposed virulence factor of Sporothrix species. To improve in locus integration of deletion constructs, we deleted the KU80 homolog that is critical for non-homologous end-joining DNA repair. The use of Δku80 strains from S. brasiliensis enhanced homologous-directed repair during transformation resulting in increased targeted gene deletion in combination with CRISPR/Cas9. In conclusion, our CRISPR/Cas9-based transformation protocol provides an efficient tool for targeted gene manipulation in Sporothrix species. IMPORTANCE Sporotrichosis caused by Sporothrix brasiliensis is a disease that requires long periods of treatment and is rapidly spreading across Latin America. The virulence of this fungus and the surge of atypical and more severe presentations of the disease raise the need for an understanding of the molecular mechanisms underlying sporotrichosis, as well as the development of better diagnostics and antifungal therapies. By developing molecular tools for accurate genetic manipulation in Sporothrix, this study addresses the paucity of reliable and reproducible tools for stable genetic engineering of Sporothrix species, which has represented a major obstacle for studying the virulence determinants and their roles in the establishment of sporotrichosis.
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Affiliation(s)
- Remi Hatinguais
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, United Kingdom
| | - Ian Leaves
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, United Kingdom
| | - Gordon D. Brown
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, United Kingdom
| | - Alistair J. P. Brown
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, United Kingdom
| | - Matthias Brock
- Fungal Biology Group, School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Roberta Peres da Silva
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, United Kingdom
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Mirhakkak MH, Chen X, Ni Y, Heinekamp T, Sae-Ong T, Xu LL, Kurzai O, Barber AE, Brakhage AA, Boutin S, Schäuble S, Panagiotou G. Genome-scale metabolic modeling of Aspergillus fumigatus strains reveals growth dependencies on the lung microbiome. Nat Commun 2023; 14:4369. [PMID: 37474497 PMCID: PMC10359302 DOI: 10.1038/s41467-023-39982-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Accepted: 07/03/2023] [Indexed: 07/22/2023] Open
Abstract
Aspergillus fumigatus, an opportunistic human pathogen, frequently infects the lungs of people with cystic fibrosis and is one of the most common causes of infectious-disease death in immunocompromised patients. Here, we construct 252 strain-specific, genome-scale metabolic models of this important fungal pathogen to study and better understand the metabolic component of its pathogenic versatility. The models show that 23.1% of A. fumigatus metabolic reactions are not conserved across strains and are mainly associated with amino acid, nucleotide, and nitrogen metabolism. Profiles of non-conserved reactions and growth-supporting reaction fluxes are sufficient to differentiate strains, for example by environmental or clinical origin. In addition, shotgun metagenomics analysis of sputum from 40 cystic fibrosis patients (15 females, 25 males) before and after diagnosis with an A. fumigatus colonization suggests that the fungus shapes the lung microbiome towards a more beneficial fungal growth environment associated with aromatic amino acid availability and the shikimate pathway. Our findings are starting points for the development of drugs or microbiome intervention strategies targeting fungal metabolic needs for survival and colonization in the non-native environment of the human lung.
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Affiliation(s)
- Mohammad H Mirhakkak
- Department of Microbiome Dynamics, Leibniz Institute for Natural Product Research and Infection Biology (Leibniz-HKI), 07745, Jena, Germany
| | - Xiuqiang Chen
- Department of Microbiome Dynamics, Leibniz Institute for Natural Product Research and Infection Biology (Leibniz-HKI), 07745, Jena, Germany
| | - Yueqiong Ni
- Department of Microbiome Dynamics, Leibniz Institute for Natural Product Research and Infection Biology (Leibniz-HKI), 07745, Jena, Germany
| | - Thorsten Heinekamp
- Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology (Leibniz-HKI), 07745, Jena, Germany
| | - Tongta Sae-Ong
- Department of Microbiome Dynamics, Leibniz Institute for Natural Product Research and Infection Biology (Leibniz-HKI), 07745, Jena, Germany
| | - Lin-Lin Xu
- Department of Microbiome Dynamics, Leibniz Institute for Natural Product Research and Infection Biology (Leibniz-HKI), 07745, Jena, Germany
| | - Oliver Kurzai
- Institute for Hygiene and Microbiology, University of Würzburg, 97080, Würzburg, Germany
- Research Group Fungal Septomics, Leibniz Institute of Natural Product Research and Infection Biology (Leibniz-HKI), 07745, Jena, Germany
- National Reference Center for Invasive Fungal Infections (NRZMyk), Leibniz Institute of Natural Product Research and Infection Biology (Leibniz-HKI), 07745, Jena, Germany
| | - Amelia E Barber
- Junior Research Group Fungal Informatics, Institute of Microbiology, Friedrich-Schiller-University Jena, 07745, Jena, Germany
| | - Axel A Brakhage
- Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology (Leibniz-HKI), 07745, Jena, Germany
- Institute of Microbiology, Friedrich Schiller University Jena, 07745, Jena, Germany
| | - Sebastien Boutin
- Department of Infectious Diseases and Microbiology, University of Lübeck, 23562, Lübeck, Germany
- Translational Lung Research Center Heidelberg (TLRC), German Center for Lung Research (DZL), University of Heidelberg, 69120, Heidelberg, Germany
| | - Sascha Schäuble
- Department of Microbiome Dynamics, Leibniz Institute for Natural Product Research and Infection Biology (Leibniz-HKI), 07745, Jena, Germany.
| | - Gianni Panagiotou
- Department of Microbiome Dynamics, Leibniz Institute for Natural Product Research and Infection Biology (Leibniz-HKI), 07745, Jena, Germany.
- Department of Medicine and State Key Laboratory of Pharmaceutical Biotechnology, University of Hong Kong, Hong Kong, China.
- Friedrich Schiller University, Faculty of Biological Sciences, Jena, 07745, Germany.
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5
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Kakoschke TK, Kleinemeier C, Knösel T, Kakoschke SC, Ebel F. The Novel Monoclonal IgG 1-Antibody AB90-E8 as a Diagnostic Tool to Rapidly Distinguish Aspergillus fumigatus from Other Human Pathogenic Aspergillus Species. J Fungi (Basel) 2023; 9:622. [PMID: 37367559 DOI: 10.3390/jof9060622] [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: 04/01/2023] [Revised: 05/22/2023] [Accepted: 05/23/2023] [Indexed: 06/28/2023] Open
Abstract
In most cases, invasive aspergillosis (IA) is caused by A. fumigatus, though infections with other Aspergillus spp. with lower susceptibilities to amphotericin B (AmB) gain ground. A. terreus, for instance, is the second leading cause of IA in humans and of serious concern because of its high propensity to disseminate and its in vitro and in vivo resistance to AmB. An early differentiation between A. fumigatus and non-A. fumigatus infections could swiftly recognize a potentially ineffective treatment with AmB and lead to the lifesaving change to a more appropriate drug regime in high-risk patients. In this study, we present the characteristics of the monoclonal IgG1-antibody AB90-E8 that specifically recognizes a surface antigen of A. fumigatus and the closely related, but not human pathogenic A. fischeri. We show immunostainings on fresh frozen sections as well as on incipient mycelium picked from agar plates with tweezers or by using the expeditious tape mount technique. All three methods have a time advantage over the common procedures currently used in the routine diagnosis of IA and outline the potential of AB90-E8 as a rapid diagnostic tool.
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Affiliation(s)
- Tamara Katharina Kakoschke
- Department of Oral and Maxillofacial Surgery and Facial Plastic Surgery, University Hospital, Ludwig-Maximilians-University Munich, Lindwurmstrasse 2a, 80337 Munich, Germany
- Institute for Infectious Diseases and Zoonoses, Ludwig-Maximilians-University Munich, 85764 Oberschleissheim, Germany
| | - Christoph Kleinemeier
- Institute for Infectious Diseases and Zoonoses, Ludwig-Maximilians-University Munich, 85764 Oberschleissheim, Germany
| | - Thomas Knösel
- Institute of Pathology, Ludwig-Maximilians-University Munich, 81377 Munich, Germany
| | - Sara Carina Kakoschke
- Department of General, Visceral and Transplant Surgery, University Hospital, Ludwig-Maximilians-University Munich, Marchioninistrasse 15, 81337 Munich, Germany
| | - Frank Ebel
- Institute for Infectious Diseases and Zoonoses, Ludwig-Maximilians-University Munich, 85764 Oberschleissheim, Germany
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Peres da Silva R, Brock M. NIH4215: A mutation-prone thiamine auxotrophic clinical Aspergillus fumigatus isolate. FRONTIERS IN FUNGAL BIOLOGY 2022; 3:908343. [PMID: 37746208 PMCID: PMC10512395 DOI: 10.3389/ffunb.2022.908343] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Accepted: 06/30/2022] [Indexed: 09/26/2023]
Abstract
Aspergillus fumigatus is the main cause of life-threatening invasive aspergillosis. Despite the availability of various antifungals, therapy remains challenging and requires further studies. Accordingly, the clinical A. fumigatus isolate NIH4215 deriving from a fatal case of human pulmonary aspergillosis has frequently been used in drug efficacy studies. Unexpectedly, our initial attempts to generate a bioluminescent reporter of strain NIH4215 for in vivo drug efficacy studies failed, as NIH4215 was unable to grow on defined minimal medium. Subsequent analyses discovered a previously undescribed thiamine auxotrophy of strain NIH4215 and transformation with thiamine biosynthesis genes from A. fumigatus strain Af293 identified the nmt1 gene as cause of the thiamine auxotrophy. Sequencing of the defective nmt1 gene revealed the loss of a cysteine codon within an essential iron-binding motif. Subsequently, the wild-type nmt1 gene was successfully used to generate a bioluminescent reporter strain in NIH4215 by simultaneously deleting the akuB locus. The resulting bioluminescent ΔakuB strains showed a high frequency of homologous integration as confirmed by generation of pyrG and niaD deletion mutants. When tested in a Galleria mellonella infection model, neither thiamine auxotrophy nor the deletion of the akuB locus had a significant effect on virulence. However, besides thiamine auxotrophy, sectors with altered morphology and albino mutants frequently arose on colony edges of strain NIH4215 and its derivatives, and stable albino mutants were successfully isolated. A proposed increased mutation rate of NIH4215 was confirmed by screening for spontaneous occurrence of fluoorotic acid resistant mutants. Independent mutations in the pyrG and pyrE gene were identified in the fluoroorotic acid resistant NIH4215 isolates and the frequency of mutation was by at least one order of magnitude higher than that observed for the clinical A. fumigatus isolate CBS144.89. In summary, despite its virulence in animal models, strain NIH4215 is a thiamine auxotroph and prone to accumulate mutations. Our results suggest that thiamine biosynthesis is dispensable for host infection and mutation-prone strains such as NIH4215 could potentially facilitate the evolution of azole resistant strains as increasingly observed in the environment.
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Affiliation(s)
| | - Matthias Brock
- University of Nottingham, School of Life Sciences, University Park, Nottingham, United Kingdom
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Henß I, Kleinemeier C, Strobel L, Brock M, Löffler J, Ebel F. Characterization of Aspergillus terreus Accessory Conidia and Their Interactions With Murine Macrophages. Front Microbiol 2022; 13:896145. [PMID: 35783442 PMCID: PMC9245049 DOI: 10.3389/fmicb.2022.896145] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Accepted: 04/27/2022] [Indexed: 11/13/2022] Open
Abstract
All Aspergillus species form phialidic conidia (PC) when the mycelium is in contact with the air. These small, asexual spores are ideally suited for an airborne dissemination in the environment. Aspergillus terreus and a few closely related species from section Terrei can additionally generate accessory conidia (AC) that directly emerge from the hyphal surface. In this study, we have identified galactomannan as a major surface antigen on AC that is largely absent from the surface of PC. Galactomannan is homogeneously distributed over the entire surface of AC and even detectable on nascent AC present on the hyphal surface. In contrast, β-glucans are only accessible in distinct structures that occur after separation of the conidia from the hyphal surface. During germination, AC show a very limited isotropic growth that has no detectable impact on the distribution of galactomannan. The AC of the strain used in this study germinate much faster than the corresponding PC, and they are more sensitive to desiccation than PC. During infection of murine J774 macrophages, AC are readily engulfed and trigger a strong tumor necrosis factor-alpha (TNFα) response. Both processes are not hampered by the presence of laminarin, which indicates that β-glucans only play a minor role in these interactions. In the phagosome, we observed that galactomannan, but not β-glucan, is released from the conidial surface and translocates to the host cell cytoplasm. AC persist in phagolysosomes, and many of them initiate germination within 24 h. In conclusion, we have identified galactomannan as a novel and major antigen on AC that clearly distinguishes them from PC. The role of this fungal-specific carbohydrate in the interactions with the immune system remains an open issue that needs to be addressed in future research.
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Affiliation(s)
- Isabell Henß
- Institute for Infectious Diseases and Zoonoses, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Christoph Kleinemeier
- Institute for Infectious Diseases and Zoonoses, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Lea Strobel
- Department of Internal Medicine II, University Hospital of Wuerzburg, Wuerzburg, Germany
| | - Matthias Brock
- Fungal Genetics and Biology, School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Jürgen Löffler
- Department of Internal Medicine II, University Hospital of Wuerzburg, Wuerzburg, Germany
| | - Frank Ebel
- Institute for Infectious Diseases and Zoonoses, Ludwig-Maximilians-University Munich, Munich, Germany
- *Correspondence: Frank Ebel
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8
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Bioluminescence imaging in Paracoccidioides spp.: A tool to monitor the infectious processes. Microbes Infect 2022; 24:104975. [DOI: 10.1016/j.micinf.2022.104975] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 03/26/2022] [Accepted: 03/28/2022] [Indexed: 12/22/2022]
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Abstract
Infections due to Aspergillus species are an acute threat to human health; members of the Aspergillus section Fumigati are the most frequently occurring agents, but depending on the local epidemiology, representatives of section Terrei or section Flavi are the second or third most important. Aspergillus terreus species complex is of great interest, as it is usually amphotericin B resistant and displays notable differences in immune interactions in comparison to Aspergillus fumigatus. The latest epidemiological surveys show an increased incidence of A. terreus as well as an expanding clinical spectrum (chronic infections) and new groups of at-risk patients being affected. Hallmarks of these non-Aspergillus fumigatus invasive mold infections are high potential for tissue invasion, dissemination, and possible morbidity due to mycotoxin production. We seek to review the microbiology, epidemiology, and pathogenesis of A. terreus species complex, address clinical characteristics, and highlight the underlying mechanisms of amphotericin B resistance. Selected topics will contrast key elements of A. terreus with A. fumigatus. We provide a comprehensive resource for clinicians dealing with fungal infections and researchers working on A. terreus pathogenesis, aiming to bridge the emerging translational knowledge and future therapeutic challenges on this opportunistic pathogen.
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Lackner M, Obermair J, Naschberger V, Raschbichler LM, Kandelbauer C, Pallua J, Metzlaff J, Furxer S, Lass-Flörl C, Binder U. Cryptic species of Aspergillus section Terrei display essential physiological features to cause infection and are similar in their virulence potential in Galleria mellonella. Virulence 2020; 10:542-554. [PMID: 31169442 PMCID: PMC6592363 DOI: 10.1080/21505594.2019.1614382] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Aspergillus species account for the majority of invasive mold infections in immunocompromised patients. Most commonly, members of the Aspergillus section Fumigati are isolated from clinical material, followed by isolates belonging to section Terrei. The section Terrei contains 16 accepted species. Six species were found to be of clinical relevance and studied for differences in growth adaptability and virulence potential. Therefore, a set of 73 isolates (22 A. terreus s.s., 8 A. alabamensis, 27 A. citrinoterreus, 2 A. floccosus, 13 A. hortai, and 1 A. neoafricanus) was studied to determine differences in (a) germination kinetics, (b) temperature tolerance, (c) oxygen stress tolerance (1% O2), and (d) a combination of the latter two. Virulence potential of phialidic (PC) and accessory conidia (AC) was studied in G. mellonella larvae, using survival as read out. Further, the formation of AC was evaluated in larval tissue. All isolates were able to grow at elevated temperature and hypoxia, with highest growth and germination rates at 37°C. A. terreus s.s., A. citrinoterreus, and A. hortai exhibited highest growth rates. Virulence potential in larvae was inoculum and temperature dependent. All species except A. floccosus formed AC and germination kinetics of AC was variable. Significantly higher virulence potential of AC was found for one A. hortai isolate. AC could be detected in larval tissue 96 h post infection. Based on these findings, cryptic species of section Terrei are well adapted to the host environment and have similar potential to cause infections.
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Affiliation(s)
- Michaela Lackner
- a Division of Hygiene and Medical Microbiology , Medical University Innsbruck , Austria
| | - Judith Obermair
- a Division of Hygiene and Medical Microbiology , Medical University Innsbruck , Austria
| | - Verena Naschberger
- a Division of Hygiene and Medical Microbiology , Medical University Innsbruck , Austria
| | | | - Carmen Kandelbauer
- a Division of Hygiene and Medical Microbiology , Medical University Innsbruck , Austria
| | - Johannes Pallua
- b Department of Pathology , Medical University Innsbruck , Austria
| | - Julia Metzlaff
- a Division of Hygiene and Medical Microbiology , Medical University Innsbruck , Austria
| | - Sibylle Furxer
- a Division of Hygiene and Medical Microbiology , Medical University Innsbruck , Austria
| | - Cornelia Lass-Flörl
- a Division of Hygiene and Medical Microbiology , Medical University Innsbruck , Austria
| | - Ulrike Binder
- a Division of Hygiene and Medical Microbiology , Medical University Innsbruck , Austria
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Van Dyck K, Rogiers O, Vande Velde G, Van Dijck P. Let's shine a light on fungal infections: A noninvasive imaging toolbox. PLoS Pathog 2020; 16:e1008257. [PMID: 32134998 PMCID: PMC7058284 DOI: 10.1371/journal.ppat.1008257] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Affiliation(s)
- Katrien Van Dyck
- Laboratory of molecular cell biology, Institute of botany and microbiology, Department of biology, KU Leuven, Leuven, Belgium
- VIB center for microbiology, Leuven, Belgium
| | - Ona Rogiers
- Laboratory of molecular cell biology, Institute of botany and microbiology, Department of biology, KU Leuven, Leuven, Belgium
- VIB center for microbiology, Leuven, Belgium
- Center for Inflammation Research, VIB, Technologiepark, Zwijnaarde, Belgium
- Department of Internal Medicine, Ghent University, Technologiepark, Zwijnaarde, Belgium
| | - Greetje Vande Velde
- Biomedical MRI/ MoSAIC, Dept. Imaging & Pathology, KU Leuven, Leuven, Belgium
| | - Patrick Van Dijck
- Laboratory of molecular cell biology, Institute of botany and microbiology, Department of biology, KU Leuven, Leuven, Belgium
- VIB center for microbiology, Leuven, Belgium
- * E-mail:
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12
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Thakur R, Shankar J. Proteome Analysis Revealed Jak/Stat Signaling and Cytoskeleton Rearrangement Proteins in Human Lung Epithelial Cells During Interaction with Aspergillus terreus. ACTA ACUST UNITED AC 2019. [DOI: 10.2174/1574362413666180529123513] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Background:
Aspergillus terreus is an emerging etiological agent of invasive and
allergic aspergillosis in immunocompromised individuals. The main risk groups are individuals
having cancer, acute leukemia and those who undergo bone marrow transplantation. The human
lung epithelial cells constitute the first line of defense against inhaled conidia of A. terreus. The
aim of the study was to understand how human lung epithelial cells respond to A. terreus conidia
during the interaction and to decipher proteins/pathways underlying in host defense.
Methods:
Protein samples were extracted from human lung epithelial cells (A549) infected with
and without A. terreus conidia. Proteins were identified using QTOF-LC-MS/MS followed by
analysis using Protein Lynx Global Services software (2.2.5) against Homo sapiens UniProt
database.
Results:
A total of 1253 proteins in human lung epithelial cells were identified during the
interaction with Aspergillus terreus conidia, whereas 427 proteins were identified in uninfected
lung epithelial cells. We have observed 63 proteins in both the conditions. Gene ontology and
KEEG pathway analysis of proteins from infected lung epithelial cells showed proteins from
cytoskeleton rearrangement, transport, transcription and signal transduction pathways, such as
Jak/Stat, NOD like receptor signaling, Toll–like receptor signaling, NF-kβ signaling and TNF
signaling pathways. These signaling proteins suggested the strong immune response in lung
epithelial cells against A. terreus conidia. Also, cytoskeleton rearrangement proteins depicted the
internalization of A. terreus conidia by human lung epithelial cells.
Conclusion:
Our study has contributed to understand the interaction response of human lung
epithelial cells during A. terreus infection. Also, our study may facilitate the identification of
inflammatory biomarker against A. terreus.
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Affiliation(s)
- R. Thakur
- Genomic Laboratory, Department of Biotechnology and Bioinformatics, Jaypee University of Information Technology, Waknaghat Solan-173234 Himachal Pradesh, India
| | - J. Shankar
- Genomic Laboratory, Department of Biotechnology and Bioinformatics, Jaypee University of Information Technology, Waknaghat Solan-173234 Himachal Pradesh, India
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13
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Generation of A Mucor circinelloides Reporter Strain-A Promising New Tool to Study Antifungal Drug Efficacy and Mucormycosis. Genes (Basel) 2018; 9:genes9120613. [PMID: 30544643 PMCID: PMC6315630 DOI: 10.3390/genes9120613] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 12/03/2018] [Accepted: 12/05/2018] [Indexed: 02/04/2023] Open
Abstract
Invasive fungal infections caused by Mucorales (mucormycosis) have increased worldwide. These life-threatening infections affect mainly, but not exclusively, immunocompromised patients, and are characterized by rapid progression, severe tissue damage and an unacceptably high rate of mortality. Still, little is known about this disease and its successful therapy. New tools to understand mucormycosis and a screening method for novel antimycotics are required. Bioluminescent imaging is a powerful tool for in vitro and in vivo approaches. Hence, the objective of this work was to generate and functionally analyze bioluminescent reporter strains of Mucor circinelloides, one mucormycosis-causing pathogen. Reporter strains were constructed by targeted integration of the firefly luciferase gene under control of the M. circinelloides promoter Pzrt1. The luciferase gene was sufficiently expressed, and light emission was detected under several conditions. Phenotypic characteristics, virulence potential and antifungal susceptibility were indifferent to the wild-type strains. Light intensity was dependent on growth conditions and biomass, being suitable to determine antifungal efficacy in vitro. This work describes for the first time the generation of reporter strains in a basal fungus that will allow real-time, non-invasive infection monitoring in insect and murine models, and the testing of antifungal efficacy by means other than survival.
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Avci P, Karimi M, Sadasivam M, Antunes-Melo WC, Carrasco E, Hamblin MR. In-vivo monitoring of infectious diseases in living animals using bioluminescence imaging. Virulence 2017; 9:28-63. [PMID: 28960132 PMCID: PMC6067836 DOI: 10.1080/21505594.2017.1371897] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Traditional methods of localizing and quantifying the presence of pathogenic microorganisms in living experimental animal models of infections have mostly relied on sacrificing the animals, dissociating the tissue and counting the number of colony forming units. However, the discovery of several varieties of the light producing enzyme, luciferase, and the genetic engineering of bacteria, fungi, parasites and mice to make them emit light, either after administration of the luciferase substrate, or in the case of the bacterial lux operon without any exogenous substrate, has provided a new alternative. Dedicated bioluminescence imaging (BLI) cameras can record the light emitted from living animals in real time allowing non-invasive, longitudinal monitoring of the anatomical location and growth of infectious microorganisms as measured by strength of the BLI signal. BLI technology has been used to follow bacterial infections in traumatic skin wounds and burns, osteomyelitis, infections in intestines, Mycobacterial infections, otitis media, lung infections, biofilm and endodontic infections and meningitis. Fungi that have been engineered to be bioluminescent have been used to study infections caused by yeasts (Candida) and by filamentous fungi. Parasitic infections caused by malaria, Leishmania, trypanosomes and toxoplasma have all been monitored by BLI. Viruses such as vaccinia, herpes simplex, hepatitis B and C and influenza, have been studied using BLI. This rapidly growing technology is expected to continue to provide much useful information, while drastically reducing the numbers of animals needed in experimental studies.
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Affiliation(s)
- Pinar Avci
- a Wellman Center for Photomedicine, Massachusetts General Hospital , Boston , MA , USA.,b Department of Dermatology , Harvard Medical School , Boston , MA , USA
| | - Mahdi Karimi
- a Wellman Center for Photomedicine, Massachusetts General Hospital , Boston , MA , USA.,c Department of Medical Nanotechnology , School of Advanced Technologies in Medicine, Iran University of Medical Sciences , Tehran , Iran.,d Cellular and Molecular Research Center, Iran University of Medical Sciences , Tehran , Iran
| | - Magesh Sadasivam
- a Wellman Center for Photomedicine, Massachusetts General Hospital , Boston , MA , USA.,e Amity Institute of Nanotechnology, Amity University Uttar Pradesh , Noida , India
| | - Wanessa C Antunes-Melo
- a Wellman Center for Photomedicine, Massachusetts General Hospital , Boston , MA , USA.,f University of Sao Paulo , Sao Carlos-SP , Brazil
| | - Elisa Carrasco
- a Wellman Center for Photomedicine, Massachusetts General Hospital , Boston , MA , USA.,g Department of Biosciences , Durham University , Durham , United Kingdom
| | - Michael R Hamblin
- a Wellman Center for Photomedicine, Massachusetts General Hospital , Boston , MA , USA.,b Department of Dermatology , Harvard Medical School , Boston , MA , USA.,h Harvard-MIT Division of Health Sciences and Technology , Cambridge , MA , USA
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Bengyella L, Yekwa EL, Subhani MN, Tambo E, Nawaz K, Hetsa BA, Iftikhar S, Waikhom SD, Roy P. Invasive Aspergillus terreus morphological transitions and immunoadaptations mediating antifungal resistance. Infect Drug Resist 2017; 10:425-436. [PMID: 29158685 PMCID: PMC5683776 DOI: 10.2147/idr.s147331] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Background and aims Aspergillus terreus Thom is a pathogen of public health and agricultural importance for its seamless abilities to expand its ecological niche. The aim of this study was holistically to investigate A. terreus morphological and immunoadaptations and their implication in antifungal resistance and proliferation during infection. Materials and methods In-depth unstructured mining of relevant peer-reviewed literature was performed for A. terreus morphological, immune, resistance, and genetic diversity based on the sequenced calmodulin-like gene. Results Accessory conidia and phialidic conidia produced by A. terreus confer discrete anti-fungal resistance that ensures survivability during therapies. Interestingly, by producing unique metabolites such as Asp–melanin and terretonin, A. terreus is capable of hijacking macrophages and scavenging iron, respectively. As such, A. terreus has established a rare mechanism to mitigate phagocytosis and swing the interaction dynamics in favor of its proliferation and survival in hosts. Conclusion It is further unraveled that besides A. terreus genetic diversity, morphological, biochemical, and immunologic adaptations associated with conidia germination and discharge of chemical signals during infection enable masking of the host defense as an integral part of its strategy to survive and rapidly colonize hosts.
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Affiliation(s)
- Louis Bengyella
- Department of Biomedical Science, The School of Basic and Biomedical Sciences, University of Health and Allied Sciences, Ho, Ghana.,Department of Biotechnology, Faculty of Applied and Computer Sciences, Vaal University of Technology, Vanderbijlpark, South Africa.,Department of Biotechnology, University of Burdwan, Bardhaman, India
| | - Elsie Laban Yekwa
- Division of Medical Virology, Stellenbosch University, Stellenbosch, South Africa
| | - Muhammad Nasir Subhani
- Department of Plant Pathology, Institute of Agricultural Sciences, University of the Punjab, Lahore, Pakistan
| | - Ernest Tambo
- Department of Biochemistry and Pharmaceutical Sciences, Université des Montagnes, Bangangté.,Department of Communications, Africa Disease Intelligence and Surveillance, Communication and Response Institute, Yaoundé, Cameroon
| | - Kiran Nawaz
- Department of Plant Pathology, Institute of Agricultural Sciences, University of the Punjab, Lahore, Pakistan
| | - Bakoena Ashton Hetsa
- Department of Biotechnology, Faculty of Applied and Computer Sciences, Vaal University of Technology, Vanderbijlpark, South Africa
| | - Sehrish Iftikhar
- Department of Plant Pathology, Institute of Agricultural Sciences, University of the Punjab, Lahore, Pakistan
| | - Sayanika Devi Waikhom
- Department of Biomedical Science, The School of Basic and Biomedical Sciences, University of Health and Allied Sciences, Ho, Ghana
| | - Pranab Roy
- Department of Biotechnology, Haldia Institute of Technology, Haldia, India
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16
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Tartor YH, Hassan FAM. Assessment of carvacrol for control of avian aspergillosis in intratracheally challenged chickens in comparison to voriconazole with a reference on economic impact. J Appl Microbiol 2017; 123:1088-1099. [PMID: 28795522 DOI: 10.1111/jam.13557] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2017] [Revised: 07/28/2017] [Accepted: 07/29/2017] [Indexed: 01/07/2023]
Abstract
AIM This study was designed to investigate the efficacy of essential oils as an alternative prophylaxis and treatment for avian aspergillosis. METHODS AND RESULTS The in vitro susceptibility of Aspergillus fumigatus strains to antifungal drugs and carvacrol, thymol, eugenol, thymoquinone and cinnamon was determined using the macrodiffusion and microdilution methods. Carvacrol has antifungal activity in comparison to voriconazole (VCZ) (MIC 0·5, 0·25 μg ml-1 respectively). While cinnamon, euganol, thymol and thymoquinone displayed moderate to weak inhibitory activity. For the efficacy study, five groups of 10-day-old chicks (n = 48) were infected intratracheally either with A. fumigatus conidia or saline (negative control). Chicks in carvacrol prophylactic and treatment (CRPT) group were fed for 10 days beginning from hatch with carvacrol (200 mg kg-1 per diet) supplemented diets. VCZ (VCZT:20 mg kg-1 body weight (BW)), carvacrol treatment (CRT, CRPT) was started upon appearance of the first clinical signs and continued for 10 days. Birds were monitored for an additional 15 days following treatment. Fungal burden and therapeutic efficacy were assessed by survival, BW, quantitative (q) culture (CFU), quantitative real-time PCR (qPCR) and histopathological changes at several time points. Serum biochemical changes were also assessed. VCZT, CRPT, CRT in comparison to the sham-treated (SHAM) group have prolonged survival (87·5, 83·4, 79·2, 41·7% respectively). In VCZT and CRPT, a significant reduction in clinical signs, lesions, CFU and qPCR counts to the limit of detection were observed. CRPT has the lowest BW reduction, economic losses and significant low total cholesterol levels. CONCLUSIONS Carvacrol has a promising potential to be used as a prophylactic and treatment against A. fumigatus. SIGNIFICANCE AND IMPACT OF THE STUDY Prognosis of avian aspergillosis is often poor due to delayed diagnosis and treatment failure. However, the widespread uses of azole prophylaxis in birds are thought to be the major driver of azole resistance. These findings create a possibility to develop an effective drug-free alternative strategy for control of avian aspergillosis.
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Affiliation(s)
- Y H Tartor
- Department of Microbiology, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Sharkia Province, Egypt
| | - F A M Hassan
- Department of Animal Wealth Development, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Sharkia Province, Egypt
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Hsieh SH, Kurzai O, Brock M. Persistence within dendritic cells marks an antifungal evasion and dissemination strategy of Aspergillus terreus. Sci Rep 2017; 7:10590. [PMID: 28878289 PMCID: PMC5587622 DOI: 10.1038/s41598-017-10914-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Accepted: 08/16/2017] [Indexed: 01/20/2023] Open
Abstract
Aspergillus terreus is an airborne human fungal pathogen causing life-threatening invasive aspergillosis in immunocompromised patients. In contrast to Aspergillus fumigatus, A. terreus infections are associated with high dissemination rates and poor response to antifungal treatment. Here, we compared the interaction of conidia from both fungal species with MUTZ-3-derived dendritic cells (DCs). After phagocytosis, A. fumigatus conidia rapidly escaped from DCs, whereas A. terreus conidia remained persisting with long-term survival. Escape from DCs was independent from DHN-melanin, as A. terreus conidia expressing wA showed no increased intracellular germination. Within DCs A. terreus conidia were protected from antifungals, whereas A. fumigatus conidia were efficiently cleared. Furthermore, while A. fumigatus conidia triggered expression of DC activation markers such as CD80, CD83, CD54, MHCII and CCR7, persistent A. terreus conidia were significantly less immunogenic. Moreover, DCs confronted with A. terreus conidia neither produced pro-inflammatory nor T-cell stimulating cytokines. However, TNF-α addition resulted in activation of DCs and provoked the expression of migration markers without inactivating intracellular A. terreus conidia. Therefore, persistence within DCs and possibly within other immune cells might contribute to the low response of A. terreus infections to antifungal treatment and could be responsible for its high dissemination rates.
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Affiliation(s)
- Shih-Hung Hsieh
- Fungal Genetics and Biology Group, School of Life Sciences, University of Nottingham, University Park, NG7 2RD, Nottingham, UK.,Microbial Biochemistry and Physiology, Leibniz Institute for Natural Product Research and Infection Biology - Hans-Knoell-Institute, Adolf-Reichwein-Str. 23, 07745, Jena, Germany
| | - Oliver Kurzai
- Institute for Hygiene and Microbiology, Medical Microbiology and Mycology, Julius-Maximilians-University Würzburg, Josef-Schneider-Str. 2, 97080, Würzburg, Germany.,Septomics Research Center, Leibniz Institute for Natural Product Research and Infection Biology - Hans-Knoell-Institute, Adolf-Reichwein-Str. 23, 07745, Jena, Germany
| | - Matthias Brock
- Fungal Genetics and Biology Group, School of Life Sciences, University of Nottingham, University Park, NG7 2RD, Nottingham, UK.
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Schulze B, Rambach G, Schwartze VU, Voigt K, Schubert K, Speth C, Jacobsen ID. Ketoacidosis alone does not predispose to mucormycosis by Lichtheimia in a murine pulmonary infection model. Virulence 2017; 8:1657-1667. [PMID: 28750194 DOI: 10.1080/21505594.2017.1360460] [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] [Indexed: 12/13/2022] Open
Abstract
Mucormycosis is a rare fungal infection; however, the number of cases increased during the last decades. The main risk factors are immunosuppression and uncontrolled diabetes mellitus. Although Lichtheimia species represent a common cause of mucormycosis in Europe, virulence and pathogenesis of this genus has not been investigated in detail yet. Using murine pulmonary infection models, we found that immunosuppression is essential for establishment of infection. The disease was characterized by necrosis, angioinvasion, thrombosis, and the lethal course of infection was associated with systemic activation of platelets. Furthermore, dissemination to internal organs was frequently observed. While the virulence potential of individual L. corymbifera and L. ramosa isolates differed, pathogenicity of both species was comparable. Although ketoacidosis promoted Rhizopus infection in mice, it did not predispose mice to infection with Lichtheimia in the absence of additional immunosuppression. This might partially explain the dominance of Rhizopus as cause of mucormycosis in countries with high prevalence of ketoacidotic patients.
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Affiliation(s)
- Bianca Schulze
- a Research Group Microbial Immunology, Leibniz Institute for Natural Product Research and Infection Biology, Hans-Knöll-Institute (HKI) , Jena , Germany
| | - Günter Rambach
- b Division of Hygiene and Medical Microbiology , Medical University of Innsbruck , Austria.,c Christian Doppler Laboratory for Invasive Fungal Infections , Innsbruck , Austria
| | - Volker U Schwartze
- d Jena Microbial Resource Collection, Leibniz Institute for Natural Product Research and Infection Biology, Hans-Knöll-Institute (HKI) , Jena , Germany.,e Friedrich Schiller University , Jena , Germany
| | - Kerstin Voigt
- d Jena Microbial Resource Collection, Leibniz Institute for Natural Product Research and Infection Biology, Hans-Knöll-Institute (HKI) , Jena , Germany.,e Friedrich Schiller University , Jena , Germany
| | - Katja Schubert
- a Research Group Microbial Immunology, Leibniz Institute for Natural Product Research and Infection Biology, Hans-Knöll-Institute (HKI) , Jena , Germany
| | - Cornelia Speth
- b Division of Hygiene and Medical Microbiology , Medical University of Innsbruck , Austria.,c Christian Doppler Laboratory for Invasive Fungal Infections , Innsbruck , Austria
| | - Ilse D Jacobsen
- a Research Group Microbial Immunology, Leibniz Institute for Natural Product Research and Infection Biology, Hans-Knöll-Institute (HKI) , Jena , Germany.,e Friedrich Schiller University , Jena , Germany
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19
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Thakur R, Shankar J. Proteome Profile of Aspergillus terreus Conidia at Germinating Stage: Identification of Probable Virulent Factors and Enzymes from Mycotoxin Pathways. Mycopathologia 2017. [PMID: 28647921 DOI: 10.1007/s11046-017-0161-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Aspergillus terreus is an emerging opportunistic fungal pathogen that causes invasive aspergillosis in immunocompromised individuals. The main risk group of individuals for this organism is leukopenic patients, individuals having cancers, bone marrow transplant persons and those who have immunological disorders. The lack of early diagnostic marker for A. terreus and intrinsic resistance to Amphotericin B, further limits the successful therapy of A. terreus-associated infections. The germination of inhaled conidia is the key step to establish successful invasion in host tissues or organs. Thus, profiling of expressed proteins during germination of conidia not only shed light on proteins that are involved in invasion or virulence but may also provide early diagnostic markers. We used nanoLC-Q-TOF to study the proteome of germinating conidia (at 16 h time points) of A. terreus. We observed expression of 373 proteins in germinating conidia of A. terreus. A total of 74 proteins were uncharacterized in the database. The expressed proteins were associated with various processes like cell wall modulation, virulence factors and secondary metabolite biosynthesis. The most abundant proteins were associated with protein biosynthesis, carbohydrate metabolism and unknown functions. Among virulent proteins, mitogen-activated protein kinase (hog1) and mitogen-activated protein kinase (mpkC) are key virulent proteins observed in our study. We observed 7 enzymes from terretonin and 10 enzymes from geodin mycotoxin biosynthesis pathway. Interestingly, we observed expression of terrelysin protein, associated with blood cell lysis. Quantitative RT-PCR analysis showed 26-fold increase in transcripts encoding for dihydrogeodin oxidase and 885-fold for terrelysin gene in germinating conidia in comparison to conidia. Further, we propose that terrelysin protein and secondary metabolite such as geodin could be explored as diagnostic marker for A. terreus-associated infections.
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Affiliation(s)
- Raman Thakur
- Department of Biotechnology and Bioinformatics, Jaypee University of Information Technology, Waknaghat Solan, Himachal Pradesh, 173234, India
| | - Jata Shankar
- Department of Biotechnology and Bioinformatics, Jaypee University of Information Technology, Waknaghat Solan, Himachal Pradesh, 173234, India.
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20
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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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21
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Huang X, Chen M, Li J, Lu X. Establishing an efficient gene-targeting system in an itaconic-acid producing Aspergillus terreus strain. Biotechnol Lett 2016; 38:1603-10. [DOI: 10.1007/s10529-016-2143-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Accepted: 05/26/2016] [Indexed: 12/24/2022]
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22
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Geib E, Gressler M, Viediernikova I, Hillmann F, Jacobsen I, Nietzsche S, Hertweck C, Brock M. A Non-canonical Melanin Biosynthesis Pathway Protects Aspergillus terreus Conidia from Environmental Stress. Cell Chem Biol 2016; 23:587-597. [DOI: 10.1016/j.chembiol.2016.03.014] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Revised: 03/15/2016] [Accepted: 03/17/2016] [Indexed: 12/18/2022]
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Dunne K, Prior AR, Murphy K, Wall N, Leen G, Rogers TR, Elnazir B, Greally P, Renwick J, Murphy P. Emergence of persistent Aspergillus terreus colonisation in a child with cystic fibrosis. Med Mycol Case Rep 2015; 9:26-30. [PMID: 26288746 PMCID: PMC4534713 DOI: 10.1016/j.mmcr.2015.07.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Revised: 07/07/2015] [Accepted: 07/23/2015] [Indexed: 11/28/2022] Open
Affiliation(s)
- Katie Dunne
- The National Children's Hospital, Tallaght Hospital, Tallaght, Dublin 24, Ireland ; Department of Clinical Microbiology, Trinity Centre for Health Science, Tallaght hospital, Trinity College Dublin, Dublin 24, Ireland
| | - Anna-Rose Prior
- The National Children's Hospital, Tallaght Hospital, Tallaght, Dublin 24, Ireland
| | - Kate Murphy
- Department of Clinical Microbiology, Trinity Centre for Health Science, Tallaght hospital, Trinity College Dublin, Dublin 24, Ireland
| | - Niall Wall
- The National Children's Hospital, Tallaght Hospital, Tallaght, Dublin 24, Ireland
| | - Geraldine Leen
- The National Children's Hospital, Tallaght Hospital, Tallaght, Dublin 24, Ireland
| | - Thomas R Rogers
- Department of Clinical Microbiology, Trinity College Dublin, St James's Hospital, Dublin 8, Ireland
| | - Basil Elnazir
- The National Children's Hospital, Tallaght Hospital, Tallaght, Dublin 24, Ireland
| | - Peter Greally
- The National Children's Hospital, Tallaght Hospital, Tallaght, Dublin 24, Ireland
| | - Julie Renwick
- The National Children's Hospital, Tallaght Hospital, Tallaght, Dublin 24, Ireland ; Department of Clinical Microbiology, Trinity Centre for Health Science, Tallaght hospital, Trinity College Dublin, Dublin 24, Ireland
| | - Philip Murphy
- The National Children's Hospital, Tallaght Hospital, Tallaght, Dublin 24, Ireland ; Department of Clinical Microbiology, Trinity Centre for Health Science, Tallaght hospital, Trinity College Dublin, Dublin 24, Ireland
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Gressler M, Meyer F, Heine D, Hortschansky P, Hertweck C, Brock M. Phytotoxin production in Aspergillus terreus is regulated by independent environmental signals. eLife 2015; 4. [PMID: 26173180 PMCID: PMC4528345 DOI: 10.7554/elife.07861] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Accepted: 07/13/2015] [Indexed: 01/09/2023] Open
Abstract
Secondary metabolites have a great potential as pharmaceuticals, but there are only a few examples where regulation of gene cluster expression has been correlated with ecological and physiological relevance for the producer. Here, signals, mediators, and biological effects of terrein production were studied in the fungus Aspergillus terreus to elucidate the contribution of terrein to ecological competition. Terrein causes fruit surface lesions and inhibits plant seed germination. Additionally, terrein is moderately antifungal and reduces ferric iron, thereby supporting growth of A. terreus under iron starvation. In accordance, the lack of nitrogen or iron or elevated methionine levels induced terrein production and was dependent on either the nitrogen response regulators AreA and AtfA or the iron response regulator HapX. Independent signal transduction allows complex sensing of the environment and, combined with its broad spectrum of biological activities, terrein provides a prominent example of adapted secondary metabolite production in response to environmental competition. DOI:http://dx.doi.org/10.7554/eLife.07861.001 Organisms produce a wide variety of small molecules called metabolites through the break down of food and other chemical reactions. Some of these molecules—known as primary metabolites—are required for growth, reproduction and other vital processes. Other molecules called secondary metabolites are not strictly required by the organism, but generally have other roles that may improve the individual’s ability to survive and reproduce. Fungi and other microbes produce a large variety of secondary metabolites, many of which are used as medicines to treat diseases in humans and other animals. For example, a molecule called lovastatin—which is produced by a fungus known as Aspergillus terreus—can reduce a human patient's risk of heart disease. However, it is not known what role many secondary metabolites play in the microbe that produced them. A. terreus lives in the soil, but it can also infect plants and animals. In addition to lovastatin, it also makes another secondary metabolite called terrein. A recent study identified the genes responsible for making terrein, and discovered that this molecule is harmful to plant cells and may help the fungus to colonize and thrive in the area immediately around plant roots, which is known as the rhizosphere. Here, Gressler et al. studied how terrein may help the fungus to cope with competitors in this environment. The experiments show that terrein increases the availability of iron and inhibits the growth of competing microbes. A shortage of iron or nitrogen-containing nutrients can stimulate the fungus to produce terrein, and elevated levels of a molecule called methionine have the same effect. These conditions are commonly found in the rhizosphere and further experiments identified several proteins in the fungus that are required for sensing them. Gressler et al.'s findings suggest that terrein helps to ensure that the fungus has sufficient nitrogen and iron to thrive in the rhizosphere. Also, this study confirms that the production of secondary metabolites in microbes can happen in response to elaborate cues from the environment, which may explain why only a limited number of secondary metabolites are produced by microbes when they are grown in the laboratory. Future studies will analyze other ways to activate the production of secondary metabolites outside of the microbe's normal environment, which may lead to the discovery of new important drugs. DOI:http://dx.doi.org/10.7554/eLife.07861.002
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Affiliation(s)
- Markus Gressler
- Microbial Biochemistry and Physiology, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knoell Institute, Jena, Germany
| | - Florian Meyer
- Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knoell Institute, Jena, Germany
| | - Daniel Heine
- Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knoell Institute, Jena, Germany
| | - Peter Hortschansky
- Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knoell Institute, Jena, Germany
| | - Christian Hertweck
- Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knoell Institute, Jena, Germany
| | - Matthias Brock
- Institute for Microbiology, Friedrich Schiller University, Jena, Germany.,Fungal Genetics and Biology Group, School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
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Maurer E, Browne N, Surlis C, Jukic E, Moser P, Kavanagh K, Lass-Flörl C, Binder U. Galleria mellonella as a host model to study Aspergillus terreus virulence and amphotericin B resistance. Virulence 2015; 6:591-8. [PMID: 26107350 PMCID: PMC4720272 DOI: 10.1080/21505594.2015.1045183] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Revised: 04/21/2015] [Accepted: 04/21/2015] [Indexed: 10/23/2022] Open
Abstract
The aim of this study was to investigate if the alternative in vivo model Galleria mellonella can be used (i) to determine differences in pathogenicity of amphotericin B (AMB) resistant and susceptible A. terreus isolates, (ii) to evaluate AMB efficacy in vivo (iii) and to correlate outcome to in vitro susceptibility data. Larvae were infected with 2 A. terreus AMB resistant (ATR) and 3 AMB susceptible (ATS) isolates and survival rates were correlated to physiological attributes and killing ability of larval haemocytes. Additionally, infected larvae were treated with different concentrations of L-AMB. Haemocyte density were ascertained to evaluate the influence of L-AMB on the larval immune cells. Larvae were sensitive to A. terreus infection in an inoculum-size and temperature dependent manner. In vitro susceptibility to L-AMB correlated with in vivo outcome of antifungal treatment, defining an AMB susceptible strain cluster of A. terreus. Susceptibility to L-AMB increased virulence potential in the larval model, but this increase was also in accordance with faster growth and less damage caused by larval haemocytes. L-AMB treatment primed the larval immune response by increasing haemocyte density. G. mellonella provides a convenient model for the in vivo screening of A. terreus virulence and treatment options, contributing to the generation of a hypothesis that can be further tested in refined experiments in mammalian models.
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Affiliation(s)
- Elisabeth Maurer
- Division of Hygiene and Medical Microbiology; Medical University of Innsbruck; Innsbruck, Austria
| | - Niall Browne
- Medical Mycology Unit; Department of Biology; Maynooth University; Maynooth; Kildare, Ireland
| | - Carla Surlis
- Medical Mycology Unit; Department of Biology; Maynooth University; Maynooth; Kildare, Ireland
| | - Emina Jukic
- Division of Hygiene and Medical Microbiology; Medical University of Innsbruck; Innsbruck, Austria
| | - Patrizia Moser
- Department of Pathology; Medical University of Innsbruck; Innsbruck, Austria
| | - Kevin Kavanagh
- Medical Mycology Unit; Department of Biology; Maynooth University; Maynooth; Kildare, Ireland
| | - Cornelia Lass-Flörl
- Division of Hygiene and Medical Microbiology; Medical University of Innsbruck; Innsbruck, Austria
| | - Ulrike Binder
- Division of Hygiene and Medical Microbiology; Medical University of Innsbruck; Innsbruck, Austria
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Gressler M, Hortschansky P, Geib E, Brock M. A new high-performance heterologous fungal expression system based on regulatory elements from the Aspergillus terreus terrein gene cluster. Front Microbiol 2015; 6:184. [PMID: 25852654 PMCID: PMC4360782 DOI: 10.3389/fmicb.2015.00184] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Accepted: 02/19/2015] [Indexed: 11/13/2022] Open
Abstract
Recently, the Aspergillus terreus terrein gene cluster was identified and selected for development of a new heterologous expression system. The cluster encodes the specific transcription factor TerR that is indispensable for terrein cluster induction. To identify TerR binding sites, different recombinant versions of the TerR DNA-binding domain were analyzed for specific motif recognition. The high affinity consensus motif TCGGHHWYHCGGH was identified from genes required for terrein production and binding site mutations confirmed their essential contribution to gene expression in A. terreus. A combination of TerR with its terA target promoter was tested as recombinant expression system in the heterologous host Aspergillus niger. TerR mediated target promoter activation was directly dependent on its transcription level. Therefore, terR was expressed under control of the regulatable amylase promoter PamyB and the resulting activation of the terA target promoter was compared with activation levels obtained from direct expression of reporters from the strong gpdA control promoter. Here, the coupled system outcompeted the direct expression system. When the coupled system was used for heterologous polyketide synthase expression high metabolite levels were produced. Additionally, expression of the Aspergillus nidulans polyketide synthase gene orsA revealed lecanoric acid rather than orsellinic acid as major polyketide synthase product. Domain swapping experiments assigned this depside formation from orsellinic acid to the OrsA thioesterase domain. These experiments confirm the suitability of the expression system especially for high-level metabolite production in heterologous hosts.
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Affiliation(s)
- Markus Gressler
- Microbial Biochemistry and Physiology, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knoell Institute Jena, Germany
| | - Peter Hortschansky
- Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knoell Institute Jena, Germany
| | - Elena Geib
- Microbial Biochemistry and Physiology, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knoell Institute Jena, Germany
| | - Matthias Brock
- Microbial Biochemistry and Physiology, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knoell Institute Jena, Germany ; Institute for Microbiology, Friedrich Schiller University Jena, Germany
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Shirkhani K, Teo I, Armstrong-James D, Shaunak S. Nebulised amphotericin B-polymethacrylic acid nanoparticle prophylaxis prevents invasive aspergillosis. NANOMEDICINE-NANOTECHNOLOGY BIOLOGY AND MEDICINE 2015; 11:1217-26. [PMID: 25791815 PMCID: PMC4503863 DOI: 10.1016/j.nano.2015.02.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Revised: 02/12/2015] [Accepted: 02/14/2015] [Indexed: 11/25/2022]
Abstract
Aspergillus species are the major life threatening fungal pathogens in transplant patients. Germination of inhaled fungal spores initiates infection, causes severe pneumonia, and has a mortality of > 50%. This is leading to the consideration of pre-exposure prophylaxis to prevent infection. We made a very low MWt amphotericin B-polymethacrylic acid nanoparticle. It was not toxic to lung epithelial cells or monocyte-derived-macrophages in-vitro, or in an in-vivo transplant immuno-suppression mouse model of life threatening invasive aspergillosis. Three days of nebuliser based prophylaxis delivered the nanoparticle effectively to lung and prevented both fungal growth and lung inflammation. Protection from disease was associated with > 99% killing of the Aspergillus and a 90% reduction in lung TNF-α; the primary driver of tissue destructive immuno-pathology. This study provides in-vivo proof-of-principle that very small and cost-effective nanoparticles can be made simply, and delivered safely and effectively to lung by the aerosol route to prevent fungal infections. From the Clinical Editor Aspergillus is an opportunistic pathogen, which affects immunocompromised patients. One novel way to help fight against this infection is pre-exposure prophylaxis. The authors here made PMA based anionic hydrogels carrying amphotericin B, with mucoadhesive behavior. They showed that aerosol route of the drug was very effective in protecting against the disease in an in-vivo model and should provide a stepping-stone towards clinical trials in the future.
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Affiliation(s)
- Khojasteh Shirkhani
- Departments of Medicine, Infectious Diseases, Immunity and Chemistry, Imperial College London, Hammersmith campus, London, UK
| | - Ian Teo
- Departments of Medicine, Infectious Diseases, Immunity and Chemistry, Imperial College London, Hammersmith campus, London, UK
| | - Darius Armstrong-James
- Departments of Medicine, Infectious Diseases, Immunity and Chemistry, Imperial College London, Hammersmith campus, London, UK
| | - Sunil Shaunak
- Departments of Medicine, Infectious Diseases, Immunity and Chemistry, Imperial College London, Hammersmith campus, London, UK.
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Hachem R, Gomes MZR, El Helou G, El Zakhem A, Kassis C, Ramos E, Jiang Y, Chaftari AM, Raad II. Invasive aspergillosis caused by Aspergillus terreus: an emerging opportunistic infection with poor outcome independent of azole therapy. J Antimicrob Chemother 2014; 69:3148-55. [PMID: 25006241 DOI: 10.1093/jac/dku241] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
OBJECTIVES Invasive aspergillosis (IA) caused by Aspergillus terreus is a significant cause of morbidity and mortality in patients with haematological malignancy (HM). Very few data are available in this patient population to differentiate IA patients with A. terreus from those with non-terreus species of Aspergillus to compare outcomes. We retrospectively investigated 513 HM patients who were treated for either definite or probable IA between June 1993 and August 2012 in a cancer centre. METHODS We compared baseline characteristics, antifungal therapies and outcomes between patients infected with A. terreus (n = 96, 18.7%) and those infected with non-terreus Aspergillus species (n = 335, 65.3%). Eighty-one patients with mixed or unspecified Aspergillus infections were excluded. RESULTS Breakthrough infections occurred more frequently in the A. terreus group (91% versus 77%, P = 0.009). A. terreus infection was associated with a lower rate of final response to antifungal therapy (21% versus 38%, P = 0.0015) and a higher rate of IA-associated mortality (51% versus 30%, P < 0.001). Multivariate analyses showed that these associations were independent of patients' clinical characteristics and the antifungal regimens they received. Factors independently associated with final response included treatment with azoles (OR 3.1, 95% CI 1.9-5.0, P < 0.0001) and Aspergillus species (A. terreus versus non-terreus Aspergillus species) (OR 0.5, 95% CI 0.3-0.98, P = 0.043). Additionally, Aspergillus species and treatment with azoles were independently associated with IA-associated mortality. CONCLUSIONS A. terreus IA in HM patients was associated with worse outcome than IA caused by non-terreus Aspergillus species. Poor prognosis in patients with invasive A. terreus infections is independent of anti-Aspergillus azole-based treatment.
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Affiliation(s)
- Ray Hachem
- Department of Infectious Diseases, Infection Control and Employee Health, The University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX 77030, USA
| | - Marisa Zenaide Ribeiro Gomes
- Department of Infectious Diseases, Infection Control and Employee Health, The University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX 77030, USA
| | - Gilbert El Helou
- Department of Infectious Diseases, Infection Control and Employee Health, The University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX 77030, USA
| | - Aline El Zakhem
- Department of Infectious Diseases, Infection Control and Employee Health, The University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX 77030, USA
| | - Christelle Kassis
- Division of Infectious Diseases, The University of Texas Health Science Center at Houston, 6431 Fannin, Houston, TX 77030, USA
| | - Elizabeth Ramos
- Division of Infectious Diseases, The University of Texas Health Science Center at Houston, 6431 Fannin, Houston, TX 77030, USA
| | - Ying Jiang
- Department of Infectious Diseases, Infection Control and Employee Health, The University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX 77030, USA
| | - Anne-Marie Chaftari
- Department of Infectious Diseases, Infection Control and Employee Health, The University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX 77030, USA
| | - Issam I Raad
- Department of Infectious Diseases, Infection Control and Employee Health, The University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX 77030, USA
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Jacobsen ID, Lüttich A, Kurzai O, Hube B, Brock M. In vivo imaging of disseminated murine Candida albicans infection reveals unexpected host sites of fungal persistence during antifungal therapy. J Antimicrob Chemother 2014; 69:2785-96. [PMID: 24951534 DOI: 10.1093/jac/dku198] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
OBJECTIVES Candida albicans is an important fungal pathogen that can cause life-threatening disseminated infections. To determine the efficacy of therapy in murine models, a determination of renal fungal burden as cfu is commonly used. However, this approach provides only a snapshot of the current situation in an individual animal and cryptic sites of infection may easily be missed. Thus, we aimed to develop real-time non-invasive imaging to monitor infection in vivo. METHODS Bioluminescent C. albicans reporter strains were developed based on a bioinformatical approach for codon optimization. The reporter strains were analysed in vitro and in vivo in the murine model of systemic candidiasis. RESULTS Reporter strains allowed the in vivo monitoring of infection and a determination of fungal burden, with a high correlation between bioluminescence and cfu count. We confirmed the kidney as the main target organ but additionally observed the translocation of C. albicans to the urinary bladder. The treatment of infected mice with caspofungin and fluconazole significantly improved the clinical outcome and clearance of C. albicans from the kidneys; however, unexpectedly, viable fungal cells persisted in the gall bladder. Fungi were secreted with bile and detected in the faeces, implicating the gall bladder as a reservoir for colonization by C. albicans after antifungal therapy. Bile extracts significantly decreased the susceptibility of C. albicans to various antifungals in vitro, thereby probably contributing to its persistence. CONCLUSIONS Using in vivo imaging, we identified cryptic sites of infection and persistence of C. albicans in the gall bladder during otherwise effective antifungal treatment. Bile appears to directly interfere with antifungal activity.
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Affiliation(s)
- Ilse D Jacobsen
- Microbial Immunology, Hans Knoell Institute, Leibniz Institute for Natural Product Research and Infection Biology, Beutenbergstrasse 11a, 07745 Jena, Germany
| | - Anja Lüttich
- Microbial Pathogenicity Mechanisms, Hans Knoell Institute, Leibniz Institute for Natural Product Research and Infection Biology, Beutenbergstrasse 11a, 07745 Jena, Germany
| | - Oliver Kurzai
- Septomics Research Center, Friedrich-Schiller University Jena and Leibniz Institute for Natural Product Research and Infection Biology, Albert-Einstein Strasse 10, 07745 Jena, Germany
| | - Bernhard Hube
- Microbial Pathogenicity Mechanisms, Hans Knoell Institute, Leibniz Institute for Natural Product Research and Infection Biology, Beutenbergstrasse 11a, 07745 Jena, Germany Friedrich Schiller University, Jena, Germany Center for Sepsis Control and Care, Universitätsklinikum Jena, Jena, Germany
| | - Matthias Brock
- Friedrich Schiller University, Jena, Germany Microbial Biochemistry and Physiology, Hans Knoell Institute, Leibniz Institute for Natural Product Research and Infection Biology, Beutenbergstrasse 11a, 07745 Jena, Germany
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Assessment of efficacy of antifungals against Aspergillus fumigatus: value of real-time bioluminescence imaging. Antimicrob Agents Chemother 2013; 57:3046-59. [PMID: 23587947 DOI: 10.1128/aac.01660-12] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Aspergillus fumigatus causes life-threatening infections, especially in immunocompromised patients. Common drugs for therapy of aspergillosis are polyenes, azoles, and echinocandins. However, despite in vitro efficacy of these antifungals, treatment failure is frequently observed. In this study, we established bioluminescence imaging to monitor drug efficacy under in vitro and in vivo conditions. In vitro assays confirmed the effectiveness of liposomal amphotericin B, voriconazole, and anidulafungin. Liposomal amphotericin B and voriconazole were fungicidal, whereas anidulafungin allowed initial germination of conidia that stopped elongation but allowed the conidia to remain viable. In vivo studies were performed with a leukopenic murine model. Mice were challenged by intranasal instillation with a bioluminescent reporter strain (5 × 10(5) and 2.5 × 10(5) conidia), and therapy efficacies of liposomal amphotericin B, voriconazole, and anidulafungin were monitored. For monotherapy, the highest treatment efficacy was observed with liposomal amphotericin B, whereas the efficacies of voriconazole and anidulafungin were strongly dependent on the infectious dose. When therapy efficacy was studied with different drug combinations, all combinations improved the rate of treatment success compared to that with monotherapy. One hundred percent survival was obtained for treatment with a combination of liposomal amphotericin B and anidulafungin, which prevented not only pulmonary infections but also infections of the sinus. In conclusion, combination therapy increases treatment success, at least in the murine infection model. In addition, our novel approach based on real-time imaging enables in vivo monitoring of drug efficacy in different organs during therapy of invasive aspergillosis.
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Jelicks LA, Lisanti MP, Machado FS, Weiss LM, Tanowitz HB, Desruisseaux MS. Imaging of small-animal models of infectious diseases. THE AMERICAN JOURNAL OF PATHOLOGY 2012. [PMID: 23201133 DOI: 10.1016/j.ajpath.2012.09.026] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Infectious diseases are the second leading cause of death worldwide. Noninvasive small-animal imaging has become an important research tool for preclinical studies of infectious diseases. Imaging studies permit enhanced information through longitudinal studies of the same animal during the infection. Herein, we briefly review recent studies of animal models of infectious disease that have used imaging modalities.
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Affiliation(s)
- Linda A Jelicks
- Department of Physiology and Biophysics and the Gruss Magnetic Resonance Research Center, Albert Einstein College of Medicine, Bronx, New York 10461, USA.
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