1
|
Brown GD, Ballou ER, Bates S, Bignell EM, Borman AM, Brand AC, Brown AJP, Coelho C, Cook PC, Farrer RA, Govender NP, Gow NAR, Hope W, Hoving JC, Dangarembizi R, Harrison TS, Johnson EM, Mukaremera L, Ramsdale M, Thornton CR, Usher J, Warris A, Wilson D. The pathobiology of human fungal infections. Nat Rev Microbiol 2024:10.1038/s41579-024-01062-w. [PMID: 38918447 DOI: 10.1038/s41579-024-01062-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/14/2024] [Indexed: 06/27/2024]
Abstract
Human fungal infections are a historically neglected area of disease research, yet they cause more than 1.5 million deaths every year. Our understanding of the pathophysiology of these infections has increased considerably over the past decade, through major insights into both the host and pathogen factors that contribute to the phenotype and severity of these diseases. Recent studies are revealing multiple mechanisms by which fungi modify and manipulate the host, escape immune surveillance and generate complex comorbidities. Although the emergence of fungal strains that are less susceptible to antifungal drugs or that rapidly evolve drug resistance is posing new threats, greater understanding of immune mechanisms and host susceptibility factors is beginning to offer novel immunotherapeutic options for the future. In this Review, we provide a broad and comprehensive overview of the pathobiology of human fungal infections, focusing specifically on pathogens that can cause invasive life-threatening infections, highlighting recent discoveries from the pathogen, host and clinical perspectives. We conclude by discussing key future challenges including antifungal drug resistance, the emergence of new pathogens and new developments in modern medicine that are promoting susceptibility to infection.
Collapse
Affiliation(s)
- Gordon D Brown
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, UK.
| | - Elizabeth R Ballou
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, UK
| | - Steven Bates
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, UK
| | - Elaine M Bignell
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, UK
| | - Andrew M Borman
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, UK
| | - Alexandra C Brand
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, UK
| | - Alistair J P Brown
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, UK
| | - Carolina Coelho
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, UK
| | - Peter C Cook
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, UK
| | - Rhys A Farrer
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, UK
| | - Nelesh P Govender
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, UK
| | - Neil A R Gow
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, UK
| | - William Hope
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, UK
| | - J Claire Hoving
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, UK
| | - Rachael Dangarembizi
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, UK
| | - Thomas S Harrison
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, UK
| | - Elizabeth M Johnson
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, UK
| | - Liliane Mukaremera
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, UK
| | - Mark Ramsdale
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, UK
| | | | - Jane Usher
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, UK
| | - Adilia Warris
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, UK
| | - Duncan Wilson
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, UK
| |
Collapse
|
2
|
Alhameed RA, Semreen MH, Hamad M, Giddey AD, Sulaiman A, Al Bataineh MT, Al-Hroub HM, Bustanji Y, Alzoubi KH, Soares NC. Multi-Omics Profiling of Candida albicans Grown on Solid Versus Liquid Media. Microorganisms 2023; 11:2831. [PMID: 38137975 PMCID: PMC10745582 DOI: 10.3390/microorganisms11122831] [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: 10/21/2023] [Revised: 11/10/2023] [Accepted: 11/16/2023] [Indexed: 12/24/2023] Open
Abstract
Candida albicans is a common pathogenic fungus that presents a challenge to healthcare facilities. It can switch between a yeast cell form that diffuses through the bloodstream to colonize internal organs and a filamentous form that penetrates host mucosa. Understanding the pathogen's strategies for environmental adaptation and, ultimately, survival, is crucial. As a complementary study, herein, a multi-omics analysis was performed using high-resolution timsTOF MS to compare the proteomes and metabolomes of Wild Type (WT) Candida albicans (strain DK318) grown on agar plates versus liquid media. Proteomic analysis revealed a total of 1793 proteins and 15,013 peptides. Out of the 1403 identified proteins, 313 proteins were significantly differentially abundant with a p-value < 0.05. Of these, 156 and 157 proteins were significantly increased in liquid and solid media, respectively. Metabolomics analysis identified 192 metabolites in total. The majority (42/48) of the significantly altered metabolites (p-value 0.05 FDR, FC 1.5), mainly amino acids, were significantly higher in solid media, while only 2 metabolites were significantly higher in liquid media. The combined multi-omics analysis provides insight into adaptative morphological changes supporting Candida albicans' life cycle and identifies crucial virulence factors during biofilm formation and bloodstream infection.
Collapse
Affiliation(s)
- Rouba Abdulsalam Alhameed
- Research Institute of Medical and Health Sciences, University of Sharjah, Sharjah P.O. Box 27227, United Arab Emirates; (R.A.A.); (M.H.); (A.S.); (H.M.A.-H.); (Y.B.); (K.H.A.)
| | - Mohammad H. Semreen
- Research Institute of Medical and Health Sciences, University of Sharjah, Sharjah P.O. Box 27227, United Arab Emirates; (R.A.A.); (M.H.); (A.S.); (H.M.A.-H.); (Y.B.); (K.H.A.)
- Department of Medicinal Chemistry, College of Pharmacy, University of Sharjah, Sharjah P.O. Box 27227, United Arab Emirates
| | - Mohamad Hamad
- Research Institute of Medical and Health Sciences, University of Sharjah, Sharjah P.O. Box 27227, United Arab Emirates; (R.A.A.); (M.H.); (A.S.); (H.M.A.-H.); (Y.B.); (K.H.A.)
- College of Health Sciences, University of Sharjah, Sharjah P.O. Box 27227, United Arab Emirates
| | - Alexander D. Giddey
- Center for Applied and Translational Genomics, Mohammed Bin Rashid University of Medicine and Health Sciences, Dubai P.O. Box 505055, United Arab Emirates;
| | - Ashna Sulaiman
- Research Institute of Medical and Health Sciences, University of Sharjah, Sharjah P.O. Box 27227, United Arab Emirates; (R.A.A.); (M.H.); (A.S.); (H.M.A.-H.); (Y.B.); (K.H.A.)
| | - Mohammad T. Al Bataineh
- Center for Biotechnology, Department of Molecular Biology and Genetics, College of Medicine and Health Sciences, Khalifa University, Abu Dhabi P.O. Box 127788, United Arab Emirates;
| | - Hamza M. Al-Hroub
- Research Institute of Medical and Health Sciences, University of Sharjah, Sharjah P.O. Box 27227, United Arab Emirates; (R.A.A.); (M.H.); (A.S.); (H.M.A.-H.); (Y.B.); (K.H.A.)
| | - Yasser Bustanji
- Research Institute of Medical and Health Sciences, University of Sharjah, Sharjah P.O. Box 27227, United Arab Emirates; (R.A.A.); (M.H.); (A.S.); (H.M.A.-H.); (Y.B.); (K.H.A.)
- College of Medicine, University of Sharjah, Sharjah P.O. Box 27227, United Arab Emirates
- School of Pharmacy, The University of Jordan, Amman 11942, Jordan
| | - Karem H. Alzoubi
- Research Institute of Medical and Health Sciences, University of Sharjah, Sharjah P.O. Box 27227, United Arab Emirates; (R.A.A.); (M.H.); (A.S.); (H.M.A.-H.); (Y.B.); (K.H.A.)
- Department of Pharmacy Practice and Pharmacotherapeutics, College of Pharmacy, University of Sharjah, Sharjah P.O. Box 27227, United Arab Emirates
| | - Nelson C. Soares
- Research Institute of Medical and Health Sciences, University of Sharjah, Sharjah P.O. Box 27227, United Arab Emirates; (R.A.A.); (M.H.); (A.S.); (H.M.A.-H.); (Y.B.); (K.H.A.)
- Department of Medicinal Chemistry, College of Pharmacy, University of Sharjah, Sharjah P.O. Box 27227, United Arab Emirates
- Laboratory of Proteomics, Department of Human Genetics, National Institute of Health Doutor Ricardo Jorge (INSA), 1649-016 Lisbon, Portugal
- Centre for Toxicogenomics and Human Health (ToxOmics), Faculdade de Lisboa, NOVA School, 1169-056 Lisbon, Portugal
| |
Collapse
|
3
|
Daud M, Dasari P, Adelfinger M, Langenhorst D, Lother J, Slavkovic-Lukic D, Berges C, Kruhm M, Galler A, Schleussner C, Luther CH, Alberter K, Althammer A, Shaikh H, Pallmann N, Bodem J, El-Mowafy M, Beilhack A, Dittrich M, Topp MS, Zipfel PF, Beyersdorf N. Enolase 1 of Candida albicans binds human CD4 + T cells and modulates naïve and memory responses. Eur J Immunol 2023; 53:e2250284. [PMID: 37503840 DOI: 10.1002/eji.202250284] [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: 11/23/2022] [Revised: 06/05/2023] [Accepted: 07/27/2023] [Indexed: 07/29/2023]
Abstract
To obtain a better understanding of the biology behind life-threatening fungal infections caused by Candida albicans, we recently conducted an in silico screening for fungal and host protein interaction partners. We report here that the extracellular domain of human CD4 binds to the moonlighting protein enolase 1 (Eno1) of C. albicans as predicted bioinformatically. By using different anti-CD4 monoclonal antibodies, we determined that C. albicans Eno1 (CaEno1) primarily binds to the extracellular domain 3 of CD4. Functionally, we observed that CaEno1 binding to CD4 activated lymphocyte-specific protein tyrosine kinase (LCK), which was also the case for anti-CD4 monoclonal antibodies tested in parallel. CaEno1 binding to naïve human CD4+ T cells skewed cytokine secretion toward a Th2 profile indicative of poor fungal control. Moreover, CaEno1 inhibited human memory CD4+ T-cell recall responses. Therapeutically, CD4+ T cells transduced with a p41/Crf1-specific T-cell receptor developed for adoptive T-cell therapy were not inhibited by CaEno1 in vitro. Together, the interaction of human CD4+ T cells with CaEno1 modulated host CD4+ T-cell responses in favor of the fungus. Thus, CaEno1 mediates not only immune evasion through its interference with complement regulators but also through the direct modulation of CD4+ T-cell responses.
Collapse
Affiliation(s)
- Muhammad Daud
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
| | - Prasad Dasari
- Leibniz Institute for Natural Product Research and Infection Biology, Hans-Knöll-Institute, Jena, Germany
| | - Marion Adelfinger
- Department of Internal Medicine II, Division of Hematology, University Hospital Würzburg, Würzburg, Germany
| | - Daniela Langenhorst
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
| | - Jasmin Lother
- Department of Internal Medicine II, Division of Hematology, University Hospital Würzburg, Würzburg, Germany
| | - Dragana Slavkovic-Lukic
- Department of Internal Medicine II, Division of Hematology, University Hospital Würzburg, Würzburg, Germany
| | - Carsten Berges
- Department of Internal Medicine II, Division of Hematology, University Hospital Würzburg, Würzburg, Germany
| | - Michaela Kruhm
- Department of Internal Medicine II, Division of Hematology, University Hospital Würzburg, Würzburg, Germany
| | | | | | | | - Karl Alberter
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
| | - Anton Althammer
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
| | - Haroon Shaikh
- Department of Internal Medicine II, Division of Hematology, University Hospital Würzburg, Würzburg, Germany
| | - Niklas Pallmann
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
| | - Jochen Bodem
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
| | - Mohammed El-Mowafy
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
- Faculty of Pharmacy, Department of Microbiology & Immunology, Mansoura University, Mansoura, Egypt
| | - Andreas Beilhack
- Department of Internal Medicine II, Division of Hematology, University Hospital Würzburg, Würzburg, Germany
| | - Marcus Dittrich
- Chair of Bioinformatics, University of Würzburg, Würzburg, Germany
- Institute of Human Genetics, University of Würzburg, Würzburg, Germany
| | - Max S Topp
- Department of Internal Medicine II, Division of Hematology, University Hospital Würzburg, Würzburg, Germany
| | - Peter F Zipfel
- Leibniz Institute for Natural Product Research and Infection Biology, Hans-Knöll-Institute, Jena, Germany
- Friedrich Schiller University, Jena, Germany
| | - Niklas Beyersdorf
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
| |
Collapse
|
4
|
Langenhorst D, Fürst AL, Alberter K, Vilhena C, Dasari P, Daud M, Heilig L, Luther CH, Dittrich M, Reiher N, Wich M, Elmowafy M, Jacobsen ID, Jungnickel B, Zipfel PF, Beyersdorf N. Soluble Enolase 1 of Candida albicans and Aspergillus fumigatus Stimulates Human and Mouse B Cells and Monocytes. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2023; 211:804-815. [PMID: 37436030 DOI: 10.4049/jimmunol.2200318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 06/23/2023] [Indexed: 07/13/2023]
Abstract
Because of the growing numbers of immunocompromised patients, the incidence of life-threatening fungal infections caused by Candida albicans and Aspergillus fumigatus is increasing. We have recently identified enolase 1 (Eno1) from A. fumigatus as an immune evasion protein. Eno1 is a fungal moonlighting protein that mediates adhesion and invasion of human cells and also immune evasion through complement inactivation. We now show that soluble Eno1 has immunostimulatory activity. We observed that Eno1 from both C. albicans and A. fumigatus directly binds to the surface of lymphocytes, preferentially human and mouse B cells. Functionally, Eno1 upregulated CD86 expression on B cells and induced proliferation. Although the receptor for fungal Eno1 on B lymphocytes is still unknown, the comparison of B cells from wild-type and MyD88-deficient mice showed that B cell activation by Eno1 required MyD88 signaling. With respect to infection biology, we noted that mouse B cells stimulated by Eno1 secreted IgM and IgG2b. These Igs bound C. albicans hyphae in vitro, suggesting that Eno1-induced Ab secretion might contribute to protection from invasive fungal disease in vivo. Eno1 also triggered the release of proinflammatory cytokines from monocytes, particularly IL-6, which is a potent activator of B cells. Together, our data shed new light on the role of secreted Eno1 in infections with C. albicans and A. fumigatus. Eno1 secretion by these pathogenic microbes appears to be a double-edged sword by supporting fungal pathogenicity while triggering (antifungal) immunity.
Collapse
Affiliation(s)
- Daniela Langenhorst
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
| | - Anna-Lisa Fürst
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
| | - Karl Alberter
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
| | - Cláudia Vilhena
- Leibniz Institute for Natural Product Research and Infection Biology, Hans-Knöll-Institute, Jena, Germany
| | - Prasad Dasari
- Leibniz Institute for Natural Product Research and Infection Biology, Hans-Knöll-Institute, Jena, Germany
| | - Muhammad Daud
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
| | - Linda Heilig
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
| | | | - Marcus Dittrich
- Chair of Bioinformatics, University of Würzburg, Würzburg, Germany
- Institute of Human Genetics, University of Würzburg, Würzburg, Germany
| | - Nadine Reiher
- Leibniz Institute for Natural Product Research and Infection Biology, Hans-Knöll-Institute, Jena, Germany
| | | | - Mohammed Elmowafy
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
- Department of Microbiology & Immunology, Faculty of Pharmacy, Mansoura University, Mansoura, Egypt
| | - Ilse D Jacobsen
- Leibniz Institute for Natural Product Research and Infection Biology, Hans-Knöll-Institute, Jena, Germany
- Friedrich Schiller University, Jena, Germany
| | | | - Peter F Zipfel
- Leibniz Institute for Natural Product Research and Infection Biology, Hans-Knöll-Institute, Jena, Germany
- Friedrich Schiller University, Jena, Germany
| | - Niklas Beyersdorf
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
| |
Collapse
|
5
|
Harpf V, Rambach G, Würzner R, Lass-Flörl C, Speth C. Candida and Complement: New Aspects in an Old Battle. Front Immunol 2020; 11:1471. [PMID: 32765510 PMCID: PMC7381207 DOI: 10.3389/fimmu.2020.01471] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Accepted: 06/05/2020] [Indexed: 01/13/2023] Open
Abstract
Candida is a dominant fungal pathogen in immunocompromised hosts, leading to opportunistic infections. Complement with its multifaceted functions is involved in the immune defense against this yeast, and recently several novel aspects have emerged in this old battle. It is clear that Candida can adopt both roles as a colonizer or as a pathogen. In our article, we focus on the molecular mechanisms of the Candida-complement interplay, which occur in disseminated disease as well as locally on skin or on mucous membranes in mouth and vagina; the mechanisms can be supposed to be the same. Activation of the complement system by Candida is facilitated by directly triggering the three dominant pathways, but also indirectly via the coagulation and fibrinolysis systems. The complement-mediated anti-Candida effects induced thereby clearly extend chemotaxis, opsonization, and phagocytosis, and even the membrane attack complex formed on the fungal surface plays a modulatory role, although lysis of the yeast per se cannot be induced due to the thick fungal cell wall. In order to avoid the hostile action of complement, several evasion mechanisms have evolved during co-evolution, comprising the avoidance of recognition, and destruction. The latter comes in many flavors, in particular the cleavage of complement proteins by yeast enzymes and the exploitation of regulatory proteins by recruiting them on the cell wall, such as factor H. The rationale behind that is that the fluid phase regulators on the fungal cell surface down-regulate complement locally. Interestingly, however, evasion protein knockout strains do not necessarily lead to an attenuated disease, so it is likely more complex in vivo than initially thought. The interactions between complement and non-albicans species also deserve attention, especially Candida auris, a recently identified drug-resistant species of medical importance. This is in particular worth investigating, as deciphering of these interactions may lead to alternative anti-fungal therapies directly targeting the molecular mechanisms.
Collapse
Affiliation(s)
- Verena Harpf
- Institute of Hygiene and Medical Microbiology, Medical University of Innsbruck, Innsbruck, Austria
| | - Günter Rambach
- Institute of Hygiene and Medical Microbiology, Medical University of Innsbruck, Innsbruck, Austria
| | - Reinhard Würzner
- Institute of Hygiene and Medical Microbiology, Medical University of Innsbruck, Innsbruck, Austria
| | - Cornelia Lass-Flörl
- Institute of Hygiene and Medical Microbiology, Medical University of Innsbruck, Innsbruck, Austria
| | - Cornelia Speth
- Institute of Hygiene and Medical Microbiology, Medical University of Innsbruck, Innsbruck, Austria
| |
Collapse
|
6
|
Singh DK, Tóth R, Gácser A. Mechanisms of Pathogenic Candida Species to Evade the Host Complement Attack. Front Cell Infect Microbiol 2020; 10:94. [PMID: 32232011 PMCID: PMC7082757 DOI: 10.3389/fcimb.2020.00094] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Accepted: 02/24/2020] [Indexed: 11/13/2022] Open
Abstract
Candida species are common colonizers of the human skin, vagina, and the gut. As human commensals, Candida species do not cause any notable damage in healthy individuals; however, in certain conditions they can initiate a wide range of diseases such as chronic disseminated candidiasis, endocarditis, vaginitis, meningitis, and endophthalmitis. The incidence of Candida caused infections has increased worldwide, with mortality rates exceeding 70% in certain patient populations. C. albicans, C. glabrata, C. tropicalis, C. parapsilosis, and C. krusei are responsible for more than 90% of Candida-related infections. Interestingly, the host immune response against these closely related fungi varies. As part of the innate immune system, complement proteins play a crucial role in host defense, protecting the host by lysing pathogens or by increasing their phagocytosis by phagocytes through opsonization. This review summarizes interactions of host complement proteins with pathogenic Candida species, including C. albicans and non-albicans Candida species such as C. parapsilosis. We will also highlight the various ways of complement activation, describe the antifungal effects of complement cascades and explore the mechanisms adopted by members of pathogenic Candida species for evading complement attack.
Collapse
Affiliation(s)
| | - Renáta Tóth
- Department of Microbiology, University of Szeged, Szeged, Hungary
| | - Attila Gácser
- Department of Microbiology, University of Szeged, Szeged, Hungary.,MTA-SZTE Lendület Mycobiome Research Group, University of Szeged, Szeged, Hungary
| |
Collapse
|
7
|
Dasari P, Koleci N, Shopova IA, Wartenberg D, Beyersdorf N, Dietrich S, Sahagún-Ruiz A, Figge MT, Skerka C, Brakhage AA, Zipfel PF. Enolase From Aspergillus fumigatus Is a Moonlighting Protein That Binds the Human Plasma Complement Proteins Factor H, FHL-1, C4BP, and Plasminogen. Front Immunol 2019; 10:2573. [PMID: 31824478 PMCID: PMC6883375 DOI: 10.3389/fimmu.2019.02573] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Accepted: 10/17/2019] [Indexed: 11/13/2022] Open
Abstract
The opportunistic fungal pathogen Aspergillus fumigatus can cause severe infections, particularly in immunocompromised individuals. Upon infection, A. fumigatus faces the powerful and directly acting immune defense of the human host. The mechanisms on how A. fumigatus evades innate immune attack and complement are still poorly understood. Here, we identify A. fumigatus enolase, AfEno1, which was also characterized as fungal allergen, as a surface ligand for human plasma complement regulators. AfEno1 binds factor H, factor-H-like protein 1 (FHL-1), C4b binding protein (C4BP), and plasminogen. Factor H attaches to AfEno1 via two regions, via short conserved repeats (SCRs) 6-7 and 19-20, and FHL-1 contacts AfEno1 via SCRs 6-7. Both regulators when bound to AfEno1 retain cofactor activity and assist in C3b inactivation. Similarly, the classical pathway regulator C4BP binds to AfEno1 and bound to AfEno1; C4BP assists in C4b inactivation. Plasminogen which binds to AfEno1 via lysine residues is accessible for the tissue-type plasminogen activator (tPA), and active plasmin cleaves the chromogenic substrate S2251, degrades fibrinogen, and inactivates C3 and C3b. Plasmin attached to swollen A. fumigatus conidia damages human A549 lung epithelial cells, reduces the cellular metabolic activity, and induces cell retraction, which results in exposure of the extracellular matrix. Thus, A. fumigatus AfEno1 is a moonlighting protein and virulence factor which recruits several human regulators. The attached human regulators allow the fungal pathogen to control complement at the level of C3 and to damage endothelial cell layers and tissue components.
Collapse
Affiliation(s)
- Prasad Dasari
- Department of Infection Biology, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knöll Institute, Jena, Germany
| | - Naile Koleci
- Department of Infection Biology, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knöll Institute, Jena, Germany
| | - Iordana A Shopova
- Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knöll Institute, Jena, Germany
| | - Dirk Wartenberg
- Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knöll Institute, Jena, Germany
| | - Niklas Beyersdorf
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
| | - Stefanie Dietrich
- Research Group Applied Systems Biology, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knöll Institute, Jena, Germany
| | - Alfredo Sahagún-Ruiz
- Laboratorio de Inmunología Molecular, Departamento de Microbiología e Inmunología, Facultad de Medicina Veterinaria y Zootecnia, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Marc Thilo Figge
- Research Group Applied Systems Biology, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knöll Institute, Jena, Germany.,Institute of Microbiology, Friedrich Schiller University, Jena, Germany
| | - Christine Skerka
- Department of Infection Biology, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knöll Institute, Jena, Germany
| | - Axel A Brakhage
- Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knöll Institute, Jena, Germany.,Institute of Microbiology, Friedrich Schiller University, Jena, Germany
| | - Peter F Zipfel
- Department of Infection Biology, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knöll Institute, Jena, Germany.,Institute of Microbiology, Friedrich Schiller University, Jena, Germany
| |
Collapse
|
8
|
Galocha M, Pais P, Cavalheiro M, Pereira D, Viana R, Teixeira MC. Divergent Approaches to Virulence in C. albicans and C. glabrata: Two Sides of the Same Coin. Int J Mol Sci 2019; 20:E2345. [PMID: 31083555 PMCID: PMC6539081 DOI: 10.3390/ijms20092345] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Revised: 05/08/2019] [Accepted: 05/08/2019] [Indexed: 12/27/2022] Open
Abstract
Candida albicans and Candida glabrata are the two most prevalent etiologic agents of candidiasis worldwide. Although both are recognized as pathogenic, their choice of virulence traits is highly divergent. Indeed, it appears that these different approaches to fungal virulence may be equally successful in causing human candidiasis. In this review, the virulence mechanisms employed by C. albicans and C. glabrata are analyzed, with emphasis on the differences between the two systems. Pathogenesis features considered in this paper include dimorphic growth, secreted enzymes and signaling molecules, and stress resistance mechanisms. The consequences of these traits in tissue invasion, biofilm formation, immune system evasion, and macrophage escape, in a species dependent manner, are discussed. This review highlights the observation that C. albicans and C. glabrata follow different paths leading to a similar outcome. It also highlights the lack of knowledge on some of the specific mechanisms underlying C. glabrata pathogenesis, which deserve future scrutiny.
Collapse
Affiliation(s)
- Mónica Galocha
- Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal.
- iBB-Institute for Bioengineering and Biosciences, Biological Sciences Research Group, Instituto Superior Técnico, University of Lisbon, Av. Rovisco Pais, 1049-001 Lisboa, Portugal.
| | - Pedro Pais
- Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal.
- iBB-Institute for Bioengineering and Biosciences, Biological Sciences Research Group, Instituto Superior Técnico, University of Lisbon, Av. Rovisco Pais, 1049-001 Lisboa, Portugal.
| | - Mafalda Cavalheiro
- Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal.
- iBB-Institute for Bioengineering and Biosciences, Biological Sciences Research Group, Instituto Superior Técnico, University of Lisbon, Av. Rovisco Pais, 1049-001 Lisboa, Portugal.
| | - Diana Pereira
- Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal.
- iBB-Institute for Bioengineering and Biosciences, Biological Sciences Research Group, Instituto Superior Técnico, University of Lisbon, Av. Rovisco Pais, 1049-001 Lisboa, Portugal.
| | - Romeu Viana
- Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal.
- iBB-Institute for Bioengineering and Biosciences, Biological Sciences Research Group, Instituto Superior Técnico, University of Lisbon, Av. Rovisco Pais, 1049-001 Lisboa, Portugal.
| | - Miguel C Teixeira
- Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal.
- iBB-Institute for Bioengineering and Biosciences, Biological Sciences Research Group, Instituto Superior Técnico, University of Lisbon, Av. Rovisco Pais, 1049-001 Lisboa, Portugal.
| |
Collapse
|
9
|
Dasari P, Shopova IA, Stroe M, Wartenberg D, Martin-Dahse H, Beyersdorf N, Hortschansky P, Dietrich S, Cseresnyés Z, Figge MT, Westermann M, Skerka C, Brakhage AA, Zipfel PF. Aspf2 From Aspergillus fumigatus Recruits Human Immune Regulators for Immune Evasion and Cell Damage. Front Immunol 2018; 9:1635. [PMID: 30166981 PMCID: PMC6106110 DOI: 10.3389/fimmu.2018.01635] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Accepted: 07/03/2018] [Indexed: 12/11/2022] Open
Abstract
The opportunistic fungal pathogen Aspergillus fumigatus can cause life-threatening infections, particularly in immunocompromised patients. Most pathogenic microbes control host innate immune responses at the earliest time, already before infiltrating host immune cells arrive at the site of infection. Here, we identify Aspf2 as the first A. fumigatus Factor H-binding protein. Aspf2 recruits several human plasma regulators, Factor H, factor-H-like protein 1 (FHL-1), FHR1, and plasminogen. Factor H contacts Aspf2 via two regions located in SCRs6–7 and SCR20. FHL-1 binds via SCRs6–7, and FHR1 via SCRs3–5. Factor H and FHL-1 attached to Aspf2-maintained cofactor activity and assisted in C3b inactivation. A Δaspf2 knockout strain was generated which bound Factor H with 28% and FHL-1 with 42% lower intensity. In agreement with less immune regulator acquisition, when challenged with complement-active normal human serum, Δaspf2 conidia had substantially more C3b (>57%) deposited on their surface. Consequently, Δaspf2 conidia were more efficiently phagocytosed (>20%) and killed (44%) by human neutrophils as wild-type conidia. Furthermore, Aspf2 recruited human plasminogen and, when activated by tissue-type plasminogen activator, newly generated plasmin cleaved the chromogenic substrate S2251 and degraded fibrinogen. Furthermore, plasmin attached to conidia damaged human lung epithelial cells, induced cell retraction, and caused matrix exposure. Thus, Aspf2 is a central immune evasion protein and plasminogen ligand of A. fumigatus. By blocking host innate immune attack and by disrupting human lung epithelial cell layers, Aspf2 assists in early steps of fungal infection and likely allows tissue penetration.
Collapse
Affiliation(s)
- Prasad Dasari
- Department of Infection Biology, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knöll Institute (HKI), Jena, Germany
| | - Iordana A Shopova
- Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Jena, Germany
| | - Maria Stroe
- Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Jena, Germany
| | - Dirk Wartenberg
- Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Jena, Germany
| | - Hans Martin-Dahse
- Department of Infection Biology, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knöll Institute (HKI), Jena, Germany
| | - Niklas Beyersdorf
- University of Würzburg, Institute for Virology and Immunobiology, Würzburg, Germany
| | - Peter Hortschansky
- Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Jena, Germany
| | - Stefanie Dietrich
- Research Group Applied Systems Biology, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Jena, Germany.,Faculty for Biological Sciences, Friedrich Schiller University, Jena, Germany
| | - Zoltán Cseresnyés
- Research Group Applied Systems Biology, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Jena, Germany
| | - Marc Thilo Figge
- Research Group Applied Systems Biology, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Jena, Germany.,Faculty for Biological Sciences, Friedrich Schiller University, Jena, Germany
| | - Martin Westermann
- Electron Microscopy Center of the University Hospital, Jena, Germany
| | - Christine Skerka
- Department of Infection Biology, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knöll Institute (HKI), Jena, Germany
| | - Axel A Brakhage
- Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Jena, Germany.,Faculty for Biological Sciences, Friedrich Schiller University, Jena, Germany
| | - Peter F Zipfel
- Department of Infection Biology, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knöll Institute (HKI), Jena, Germany.,Faculty for Biological Sciences, Friedrich Schiller University, Jena, Germany
| |
Collapse
|
10
|
The secreted Candida albicans protein Pra1 disrupts host defense by broadly targeting and blocking complement C3 and C3 activation fragments. Mol Immunol 2017; 93:266-277. [PMID: 28860090 DOI: 10.1016/j.molimm.2017.07.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Revised: 07/12/2017] [Accepted: 07/18/2017] [Indexed: 11/23/2022]
Abstract
Candida albicans the most frequently isolated clinical fungal pathogen can cause local as well as systemic and life-threatening infections particularly in immune-compromised individuals. A better and more detailed understanding how C. albicans evades human immune attack is therefore needed for identifying fungal immune-evasive proteins and develop new therapies. Here, we identified Pra1, the pH-regulated C. albicans antigen as a hierarchical complement inhibitor that targets C3, the central human complement component. Pra1 cleaved C3 at a unique site and further inhibited effector function of the activation fragments. The newly formed C3a-like peptide lacked the C-terminal arginine residue needed for C3a-receptor binding and activation. Moreover, Pra1 also blocked C3a-like antifungal activity as shown in survival assays, and the C3b-like molecule formed by Pra1 was degraded by the host protease Factor I. Pra1 also bound to C3a and C3b generated by human convertases and blocked their effector functions, like C3a antifungal activity shown by fungal survival, blocked C3a binding to human C3a receptor-expressing HEK cells, activation of Fura2-AM loaded cells, intracellular Ca2+ signaling, IL-8 release, C3b deposition, as well as opsonophagocytosis and killing by human neutrophils. Thus, upon infection C. albicans uses Pra1 to destroy C3 and to disrupt host complement attack. In conclusion, candida Pra1 represents the first fungal C3-cleaving protease identified and functions as a fungal master regulator of innate immunity and as a central fungal immune-escape protein.
Collapse
|