1
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Silva VKA, Min S, Yoo K, Fries BC. Host-Pathogen Interactions and Correlated Factors That Are Affected in Replicative-Aged Cryptococcus neoformans. J Fungi (Basel) 2024; 10:279. [PMID: 38667950 PMCID: PMC11050866 DOI: 10.3390/jof10040279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2024] [Revised: 03/27/2024] [Accepted: 04/04/2024] [Indexed: 04/28/2024] Open
Abstract
Cryptococcus neoformans is a facultative intracellular fungal pathogen. Ten-generation-old (10GEN) C. neoformans cells are more resistant to phagocytosis and killing by macrophages than younger daughter cells. However, mechanisms that mediate this resistance and intracellular parasitism are poorly understood. Here, we identified important factors for the intracellular survival of 10GEN C. neoformans, such as urease activity, capsule synthesis, and DNA content using flow cytometry and fluorescent microscopy techniques. The real-time visualization of time-lapse imaging was applied to determine the phagosomal acidity, membrane permeability, and vomocytosis (non-lytic exocytosis) rate in J774 macrophages that phagocytosed C. neoformans of different generational ages. Our results showed that old C. neoformans exhibited higher urease activity and enhanced Golgi activity. In addition, old C. neoformans were more likely to be arrested in the G2 phase, resulting in the occasional formation of aberrant trimera-like cells. To finish, the advanced generational age of the yeast cells slightly reduced vomocytosis events within host cells, which might be associated with increased phagolysosome pH and membrane permeability. Altogether, our results suggest that old C. neoformans prevail within acidic phagolysosomes and can manipulate the phagosome pH. These strategies may be used by old C. neoformans to resist phagosomal killing and drive cryptococcosis pathogenesis. The comprehension of these essential host-pathogen interactions could further shed light on mechanisms that bring new insights for novel antifungal therapeutic design.
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Affiliation(s)
- Vanessa K. A. Silva
- Division of Infectious Diseases, Department of Medicine, Stony Brook University, Stony Brook, NY 11794, USA; (V.K.A.S.); (S.M.)
| | - Sungyun Min
- Division of Infectious Diseases, Department of Medicine, Stony Brook University, Stony Brook, NY 11794, USA; (V.K.A.S.); (S.M.)
| | - Kyungyoon Yoo
- Department of Microbiology and Immunology, Renaissance School of Medicine, Stony Brook University, Stony Brook, NY 11794, USA;
| | - Bettina C. Fries
- Division of Infectious Diseases, Department of Medicine, Stony Brook University, Stony Brook, NY 11794, USA; (V.K.A.S.); (S.M.)
- Department of Microbiology and Immunology, Renaissance School of Medicine, Stony Brook University, Stony Brook, NY 11794, USA;
- Veterans Administration Medical Center, Northport, NY 11768, USA
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2
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Onyishi CU, Jeon Y, Fejer G, Mukhopadhyay S, Gordon S, May RC. Loss of the scavenger receptor MARCO results in uncontrolled vomocytosis of fungi from macrophages. Eur J Immunol 2024:e2350771. [PMID: 38494423 DOI: 10.1002/eji.202350771] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Revised: 03/03/2024] [Accepted: 03/05/2024] [Indexed: 03/19/2024]
Abstract
Vomocytosis, also known as nonlytic exocytosis, is a process whereby fully phagocytosed microbes are expelled from phagocytes without discernible damage to either the phagocyte or microbe. Although this phenomenon was first described in the opportunistic fungal pathogen Cryptococcus neoformans in 2006, to date, mechanistic studies have been hampered by an inability to reliably stimulate or inhibit vomocytosis. Here we present the fortuitous discovery that macrophages lacking the scavenger receptor MAcrophage Receptor with COllagenous domain (MARCO), exhibit near-total vomocytosis of internalised cryptococci within a few hours of infection. Marco-/- macrophages also showed elevated vomocytosis of a yeast-locked C. albicans strain, suggesting this to be a broadly relevant observation. We go on to show that MARCO's role in modulating vomocytosis is independent of its role as a phagocytic receptor, suggesting that this protein may play an important and hitherto unrecognised role in modulating macrophage behaviour.
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Affiliation(s)
- Chinaemerem U Onyishi
- Institute of Microbiology & Infection and School of Biosciences, University of Birmingham, Edgbaston, Birmingham, UK
- Molecular Mycology and Immunity Section, Laboratory of Host Immunity and Microbiome, National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health, Bethesda, MD, USA
| | - Yusun Jeon
- Peter Gorer Department of Immunobiology, School of Immunology & Microbial Sciences, King's College London, London, UK
| | - Gyorgy Fejer
- School of Biomedical Sciences, Faculty of Health, University of Plymouth, Plymouth, UK
| | - Subhankar Mukhopadhyay
- Peter Gorer Department of Immunobiology, School of Immunology & Microbial Sciences, King's College London, London, UK
| | - Siamon Gordon
- Department of Microbiology and Immunology, College of Medicine, Chang Gung University, Taoyuan, Taiwan
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | - Robin C May
- Institute of Microbiology & Infection and School of Biosciences, University of Birmingham, Edgbaston, Birmingham, UK
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3
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Pacifici N, Cruz-Acuña M, Diener A, Tu A, Senthil N, Han H, Lewis JS. Vomocytosis of Cryptococcus neoformans cells from murine, bone marrow-derived dendritic cells. PLoS One 2023; 18:e0280692. [PMID: 36928392 PMCID: PMC10019626 DOI: 10.1371/journal.pone.0280692] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 01/05/2023] [Indexed: 03/18/2023] Open
Abstract
Cryptococcus neoformans (CN) cells survive within the acidic phagolysosome of macrophages (MΦ) for extended times, then escape without impacting the viability of the host cell via a phenomenon that has been coined 'vomocytosis'. Through this mechanism, CN disseminate throughout the body, sometimes resulting in a potentially fatal condition-Cryptococcal Meningitis (CM). Justifiably, vomocytosis studies have focused primarily on MΦ, as alveolar MΦ within the lung act as first responders that ultimately expel this fungal pathogen. Herein, we hypothesize that dendritic cells (DCs), an innate immune cell with attributes that include phagocytosis and antigen presentation, can also act as 'vomocytes'. Presciently, this report shows that vomocytosis of CN indeed occurs from murine, bone marrow-derived DCs. Primarily through time-lapse microscopy imaging, we show that rates of vomocytosis events from DCs are comparable to those seen from MΦ and further, are independent of the presence of the CN capsule and infection ratios. Moreover, the phagosome-altering drug bafilomycin A inhibits this phenomenon from DCs. Although DC immunophenotype does not affect the total number of vomocytic events, we observed differences in the numbers of CN per phagosome and expulsion times. Interestingly, these observations were similar in murine, bone marrow-derived MΦ. This work not only demonstrates the vomocytic ability of DCs, but also investigates the complexity of vomocytosis regulation in this cell type and MΦ under multiple modulatory conditions. Understanding the vomocytic behavior of different phagocytes and their phenotypic subtypes is needed to help elucidate the full picture of the dynamic interplay between CN and the immune system. Critically, deeper insight into vomocytosis could reveal novel approaches to treat CM, as well as other immune-related conditions.
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Affiliation(s)
- Noah Pacifici
- Department of Biomedical Engineering, University of California—Davis, Davis, CA, United States of America
| | - Melissa Cruz-Acuña
- Department of Biomedical Engineering, University of California—Davis, Davis, CA, United States of America
| | - Agustina Diener
- Department of Biomedical Engineering, University of California—Davis, Davis, CA, United States of America
| | - Allen Tu
- Department of Biomedical Engineering, University of California—Davis, Davis, CA, United States of America
| | - Neeraj Senthil
- Department of Biomedical Engineering, University of California—Davis, Davis, CA, United States of America
| | - Hyunsoo Han
- Department of Biomedical Engineering, University of California—Davis, Davis, CA, United States of America
| | - Jamal S. Lewis
- Department of Biomedical Engineering, University of California—Davis, Davis, CA, United States of America
- J. Crayton Pruitt Family Department of Biomedical Engineering, Gainesville, FL, United States of America
- * E-mail:
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4
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Burgess TB, Condliffe AM, Elks PM. A Fun-Guide to Innate Immune Responses to Fungal Infections. J Fungi (Basel) 2022; 8:805. [PMID: 36012793 PMCID: PMC9409918 DOI: 10.3390/jof8080805] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 07/26/2022] [Accepted: 07/28/2022] [Indexed: 11/22/2022] Open
Abstract
Immunocompromised individuals are at high risk of developing severe fungal infections with high mortality rates, while fungal pathogens pose little risk to most healthy people. Poor therapeutic outcomes and growing antifungal resistance pose further challenges for treatments. Identifying specific immunomodulatory mechanisms exploited by fungal pathogens is critical for our understanding of fungal diseases and development of new therapies. A gap currently exists between the large body of literature concerning the innate immune response to fungal infections and the potential manipulation of host immune responses to aid clearance of infection. This review considers the innate immune mechanisms the host deploys to prevent fungal infection and how these mechanisms fail in immunocompromised hosts. Three clinically relevant fungal pathogens (Candida albicans, Cryptococcus spp. and Aspergillus spp.) will be explored. This review will also examine potential mechanisms of targeting the host therapeutically to improve outcomes of fungal infection.
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5
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Gibson JF, Bojarczuk A, Evans RJ, Kamuyango AA, Hotham R, Lagendijk AK, Hogan BM, Ingham PW, Renshaw SA, Johnston SA. Blood vessel occlusion by Cryptococcus neoformans is a mechanism for haemorrhagic dissemination of infection. PLoS Pathog 2022; 18:e1010389. [PMID: 35446924 PMCID: PMC9022829 DOI: 10.1371/journal.ppat.1010389] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 02/21/2022] [Indexed: 11/18/2022] Open
Abstract
Meningitis caused by infectious pathogens is associated with vessel damage and infarct formation, however the physiological cause is often unknown. Cryptococcus neoformans is a human fungal pathogen and causative agent of cryptococcal meningitis, where vascular events are observed in up to 30% of patients, predominantly in severe infection. Therefore, we aimed to investigate how infection may lead to vessel damage and associated pathogen dissemination using a zebrafish model that permitted noninvasive in vivo imaging. We find that cryptococcal cells become trapped within the vasculature (dependent on their size) and proliferate there resulting in vasodilation. Localised cryptococcal growth, originating from a small number of cryptococcal cells in the vasculature was associated with sites of dissemination and simultaneously with loss of blood vessel integrity. Using a cell-cell junction tension reporter we identified dissemination from intact blood vessels and where vessel rupture occurred. Finally, we manipulated blood vessel tension via cell junctions and found increased tension resulted in increased dissemination. Our data suggest that global vascular vasodilation occurs following infection, resulting in increased vessel tension which subsequently increases dissemination events, representing a positive feedback loop. Thus, we identify a mechanism for blood vessel damage during cryptococcal infection that may represent a cause of vascular damage and cortical infarction during cryptococcal meningitis. Meningitis is a life threatening form of infection in the brain that is difficult to treat. How infection spreads from the blood to cause meningitis is not well understood. Here we have shown how infection with the fungus Cryptococcus neoformans can be spread from the blood by blocking and bursting blood vessels. Using zebrafish larvae, we were able to follow the same infections over a period of days to understand how this infection behaves in blood vessels. We found that fungal cells become stuck within blood vessels depending on their size. These cells grow within blood vessels, resulting in the blood vessels becoming wider. We measured increased tension in blood vessels suggesting that, with the bloackage and widening of vessels, there was increased local blood pressure. We found that vessel blockage was associated with their rupture and spreading of fungus into the surround tissue. Finally, by increasing the tension in vessels we could increase the number of blood bursting events supporting our conclusion that blood vessel blockage leads to the spread of the infection outside of blood vessels.
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Affiliation(s)
- Josie F. Gibson
- Department of Infection, Immunity and Cardiovascular disease, Bateson Centre and Florey Institute, University of Sheffield, United Kingdom
- Institute of Molecular and Cell Biology, Agency of Science, Technology and Research (A-Star), Singapore
| | - Aleksandra Bojarczuk
- Department of Infection, Immunity and Cardiovascular disease, Bateson Centre and Florey Institute, University of Sheffield, United Kingdom
- Faculty of Physical Education, Gdansk University of Physical Education and Sport, Gdansk, Poland
| | - Robert J. Evans
- Department of Infection, Immunity and Cardiovascular disease, Bateson Centre and Florey Institute, University of Sheffield, United Kingdom
| | - Alfred Alinafe Kamuyango
- Department of Infection, Immunity and Cardiovascular disease, Bateson Centre and Florey Institute, University of Sheffield, United Kingdom
| | - Richard Hotham
- Department of Infection, Immunity and Cardiovascular disease, Bateson Centre and Florey Institute, University of Sheffield, United Kingdom
| | - Anne K. Lagendijk
- Division of Genomics of Development and Disease, Institute for Molecular Bioscience, University of Queensland, Brisbane, Australia
| | - Benjamin M. Hogan
- Division of Genomics of Development and Disease, Institute for Molecular Bioscience, University of Queensland, Brisbane, Australia
| | - Philip W. Ingham
- Institute of Molecular and Cell Biology, Agency of Science, Technology and Research (A-Star), Singapore
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore
| | - Stephen A. Renshaw
- Department of Infection, Immunity and Cardiovascular disease, Bateson Centre and Florey Institute, University of Sheffield, United Kingdom
| | - Simon A. Johnston
- Department of Infection, Immunity and Cardiovascular disease, Bateson Centre and Florey Institute, University of Sheffield, United Kingdom
- * E-mail:
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6
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Wang Y, Pawar S, Dutta O, Wang K, Rivera A, Xue C. Macrophage Mediated Immunomodulation During Cryptococcus Pulmonary Infection. Front Cell Infect Microbiol 2022; 12:859049. [PMID: 35402316 PMCID: PMC8987709 DOI: 10.3389/fcimb.2022.859049] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 02/28/2022] [Indexed: 12/21/2022] Open
Abstract
Macrophages are key cellular components of innate immunity, acting as the first line of defense against pathogens to modulate homeostatic and inflammatory responses. They help clear pathogens and shape the T-cell response through the production of cytokines and chemokines. The facultative intracellular fungal pathogen Cryptococcus neoformans has developed a unique ability to interact with and manipulate host macrophages. These interactions dictate how Cryptococcus infection can remain latent or how dissemination within the host is achieved. In addition, differences in the activities of macrophages have been correlated with differential susceptibilities of hosts to Cryptococcus infection, highlighting the importance of macrophages in determining disease outcomes. There is now abundant information on the interaction between Cryptococcus and macrophages. In this review we discuss recent advances regarding macrophage origin, polarization, activation, and effector functions during Cryptococcus infection. The importance of these strategies in pathogenesis and the potential of immunotherapy for cryptococcosis treatment is also discussed.
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Affiliation(s)
- Yan Wang
- Public Health Research Institute, New Jersey Medical School, Rutgers University, Newark, NJ, United States
- Department of Microbiology and Immunology , Guangdong Medical University, Dongguan, China
| | - Siddhi Pawar
- Public Health Research Institute, New Jersey Medical School, Rutgers University, Newark, NJ, United States
| | - Orchi Dutta
- Public Health Research Institute, New Jersey Medical School, Rutgers University, Newark, NJ, United States
| | - Keyi Wang
- Center for Immunity and Inflammation, New Jersey Medical School, Rutgers University, Newark, NJ, United States
| | - Amariliz Rivera
- Center for Immunity and Inflammation, New Jersey Medical School, Rutgers University, Newark, NJ, United States
| | - Chaoyang Xue
- Public Health Research Institute, New Jersey Medical School, Rutgers University, Newark, NJ, United States
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7
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Ortega-Muelas M, Roche O, Fernández-Aroca DM, Encinar JA, Albandea-Rodríguez D, Arconada-Luque E, Pascual-Serra R, Muñoz I, Sánchez-Pérez I, Belandia B, Ruiz-Hidalgo MJ, Sánchez-Prieto R. ERK5 signalling pathway is a novel target of sorafenib: Implication in EGF biology. J Cell Mol Med 2021; 25:10591-10603. [PMID: 34655447 PMCID: PMC8581332 DOI: 10.1111/jcmm.16990] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 09/10/2021] [Accepted: 09/30/2021] [Indexed: 12/16/2022] Open
Abstract
Sorafenib is a multikinase inhibitor widely used in cancer therapy with an antitumour effect related to biological processes as proliferation, migration or invasion, among others. Initially designed as a Raf inhibitor, Sorafenib was later shown to also block key molecules in tumour progression such as VEGFR and PDGFR. In addition, sorafenib has been connected with key signalling pathways in cancer such as EGFR/EGF. However, no definitive clue about the molecular mechanism linking sorafenib and EGF signalling pathway has been established so far. Our data in HeLa, U2OS, A549 and HEK293T cells, based on in silico, chemical and genetic approaches demonstrate that the MEK5/ERK5 signalling pathway is a novel target of sorafenib. In addition, our data show how sorafenib is able to block MEK5-dependent phosphorylation of ERK5 in the Ser218/Tyr220, affecting the transcriptional activation associated with ERK5. Moreover, we demonstrate that some of the effects of this kinase inhibitor onto EGF biological responses, such as progression through cell cycle or migration, are mediated through the effect exerted onto ERK5 signalling pathway. Therefore, our observations describe a novel target of sorafenib, the ERK5 signalling pathway, and establish new mechanistic insights for the antitumour effect of this multikinase inhibitor.
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Affiliation(s)
- Marta Ortega-Muelas
- Laboratorio de Oncología Molecular, Unidad de Medicina Molecular, Centro Regional de Investigaciones Biomédicas Universidad de Castilla-La Mancha, Unidad Asociada de Biomedicina UCLM, Unidad asociada al CSIC, Albacete, Spain
| | - Olga Roche
- Laboratorio de Oncología Molecular, Unidad de Medicina Molecular, Centro Regional de Investigaciones Biomédicas Universidad de Castilla-La Mancha, Unidad Asociada de Biomedicina UCLM, Unidad asociada al CSIC, Albacete, Spain.,Departamento de Ciencias Médicas, Facultad de Medicina, Universidad de Castilla-La Mancha, Albacete, Spain
| | - Diego M Fernández-Aroca
- Laboratorio de Oncología Molecular, Unidad de Medicina Molecular, Centro Regional de Investigaciones Biomédicas Universidad de Castilla-La Mancha, Unidad Asociada de Biomedicina UCLM, Unidad asociada al CSIC, Albacete, Spain
| | - José A Encinar
- Instituto de Investigación, Desarrollo e Innovación en Biotecnología de Elche (IDiBE) e Instituto de Biología Molecular y Celular (IBMC), Universidad Miguel Hernández (UMH), Elche, Spain
| | - David Albandea-Rodríguez
- Departamento de Biología del Cáncer, Instituto de Investigaciones Biomédicas 'Alberto Sols' (CSIC-UAM), Unidad asociada de Biomedicina UCLM, Unidad asociada al CSIC, Madrid, Spain
| | - Elena Arconada-Luque
- Laboratorio de Oncología Molecular, Unidad de Medicina Molecular, Centro Regional de Investigaciones Biomédicas Universidad de Castilla-La Mancha, Unidad Asociada de Biomedicina UCLM, Unidad asociada al CSIC, Albacete, Spain
| | - Raquel Pascual-Serra
- Laboratorio de Oncología Molecular, Unidad de Medicina Molecular, Centro Regional de Investigaciones Biomédicas Universidad de Castilla-La Mancha, Unidad Asociada de Biomedicina UCLM, Unidad asociada al CSIC, Albacete, Spain
| | - Ismael Muñoz
- Departamento de Biología del Cáncer, Instituto de Investigaciones Biomédicas 'Alberto Sols' (CSIC-UAM), Unidad asociada de Biomedicina UCLM, Unidad asociada al CSIC, Madrid, Spain
| | - Isabel Sánchez-Pérez
- Departamento de Bioquímica, Facultad de Medicina, Instituto de Investigaciones Biomédicas 'Alberto Sols' (CSIC-UAM), Unidad asociada de Biomedicina UCLM, Unidad asociada al CSIC, Madrid, Spain
| | - Borja Belandia
- Departamento de Biología del Cáncer, Instituto de Investigaciones Biomédicas 'Alberto Sols' (CSIC-UAM), Unidad asociada de Biomedicina UCLM, Unidad asociada al CSIC, Madrid, Spain
| | - María J Ruiz-Hidalgo
- Laboratorio de Oncología Molecular, Unidad de Medicina Molecular, Centro Regional de Investigaciones Biomédicas Universidad de Castilla-La Mancha, Unidad Asociada de Biomedicina UCLM, Unidad asociada al CSIC, Albacete, Spain.,Área de Bioquímica y Biología Molecular. Facultad de Medicina, Universidad de Castilla-La Mancha, Albacete, Spain
| | - Ricardo Sánchez-Prieto
- Laboratorio de Oncología Molecular, Unidad de Medicina Molecular, Centro Regional de Investigaciones Biomédicas Universidad de Castilla-La Mancha, Unidad Asociada de Biomedicina UCLM, Unidad asociada al CSIC, Albacete, Spain.,Departamento de Ciencias Médicas, Facultad de Medicina, Universidad de Castilla-La Mancha, Albacete, Spain.,Instituto de Investigaciones Biomédicas 'Alberto Sols', Consejo Superior de Investigaciones Científicas (IIBM-CSIC)-Universidad de Castilla-La Mancha (UCLM), Albacete, Spain
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8
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Jacobovitz MR, Rupp S, Voss PA, Maegele I, Gornik SG, Guse A. Dinoflagellate symbionts escape vomocytosis by host cell immune suppression. Nat Microbiol 2021; 6:769-782. [PMID: 33927382 PMCID: PMC7611106 DOI: 10.1038/s41564-021-00897-w] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Accepted: 03/25/2021] [Indexed: 02/02/2023]
Abstract
Alveolata comprises diverse taxa of single-celled eukaryotes, many of which are renowned for their ability to live inside animal cells. Notable examples are apicomplexan parasites and dinoflagellate symbionts, the latter of which power coral reef ecosystems. Although functionally distinct, they evolved from a common, free-living ancestor and must evade their host's immune response for persistence. Both the initial cellular events that gave rise to this intracellular lifestyle and the role of host immune modulation in coral-dinoflagellate endosymbiosis are poorly understood. Here, we use a comparative approach in the cnidarian endosymbiosis model Aiptasia, which re-establishes endosymbiosis with free-living dinoflagellates every generation. We find that uptake of microalgae is largely indiscriminate, but non-symbiotic microalgae are expelled by vomocytosis, while symbionts induce host cell innate immune suppression and form a lysosomal-associated membrane protein 1-positive niche. We demonstrate that exogenous immune stimulation results in symbiont expulsion and, conversely, inhibition of canonical Toll-like receptor signalling enhances infection of host animals. Our findings indicate that symbiosis establishment is dictated by local innate immune suppression, to circumvent expulsion and promote niche formation. This work provides insight into the evolution of the cellular immune response and key steps involved in mediating endosymbiotic interactions.
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Affiliation(s)
- Marie R Jacobovitz
- Centre for Organismal Studies (COS), Heidelberg University, Heidelberg, Germany
| | - Sebastian Rupp
- Centre for Organismal Studies (COS), Heidelberg University, Heidelberg, Germany
| | - Philipp A Voss
- Centre for Organismal Studies (COS), Heidelberg University, Heidelberg, Germany
| | - Ira Maegele
- Centre for Organismal Studies (COS), Heidelberg University, Heidelberg, Germany
| | - Sebastian G Gornik
- Centre for Organismal Studies (COS), Heidelberg University, Heidelberg, Germany
| | - Annika Guse
- Centre for Organismal Studies (COS), Heidelberg University, Heidelberg, Germany.
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9
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Pradhan A, Ma Q, de Assis LJ, Leaves I, Larcombe DE, Rodriguez Rondon AV, Nev OA, Brown AJP. Anticipatory Stress Responses and Immune Evasion in Fungal Pathogens. Trends Microbiol 2021; 29:416-427. [PMID: 33059975 DOI: 10.1016/j.tim.2020.09.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 09/10/2020] [Accepted: 09/22/2020] [Indexed: 12/17/2022]
Abstract
In certain niches, microbes encounter environmental challenges that are temporally linked. In such cases, microbial fitness is enhanced by the evolution of anticipatory responses where the initial challenge simultaneously activates pre-emptive protection against the second impending challenge. The accumulation of anticipatory responses in domesticated yeasts, which have been termed 'adaptive prediction', has led to the emergence of 'core stress responses' that provide stress cross-protection. Protective anticipatory responses also seem to be common in fungal pathogens of humans. These responses reflect the selective pressures that these fungi have faced relatively recently in their evolutionary history. Consequently, some pathogens have evolved 'core environmental responses' which exploit host signals to trigger immune evasion strategies that protect them against imminent immune attack.
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Affiliation(s)
- Arnab Pradhan
- Medical Research Council Centre for Medical Mycology, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter EX4 4QD, UK
| | - Qinxi Ma
- Medical Research Council Centre for Medical Mycology, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter EX4 4QD, UK
| | - Leandro J de Assis
- Medical Research Council Centre for Medical Mycology, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter EX4 4QD, UK
| | - Ian Leaves
- Medical Research Council Centre for Medical Mycology, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter EX4 4QD, UK
| | - Daniel E Larcombe
- Medical Research Council Centre for Medical Mycology, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter EX4 4QD, UK
| | - Alejandra V Rodriguez Rondon
- Medical Research Council Centre for Medical Mycology, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter EX4 4QD, UK
| | - Olga A Nev
- Medical Research Council Centre for Medical Mycology, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter EX4 4QD, UK
| | - Alistair J P Brown
- Medical Research Council Centre for Medical Mycology, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter EX4 4QD, UK.
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10
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Abstract
Fungal infections are an increasing threat to global public health. There are more than six million fungal species worldwide, but less than 1% are known to infect humans. Most of these fungal infections are superficial, affecting the hair, skin and nails, but some species are capable of causing life-threatening diseases. The most common of these include Cryptococcus neoformans, Aspergillus fumigatus and Candida albicans. These fungi are typically innocuous and even constitute a part of the human microbiome, but if these pathogens disseminate throughout the body, they can cause fatal infections which account for more than one million deaths worldwide each year. Thus, systemic dissemination of fungi is a critical step in the development of these deadly infections. In this review, we discuss our current understanding of how fungi disseminate from the initial infection sites to the bloodstream, how immune cells eliminate fungi from circulation and how fungi leave the blood and enter distant organs, highlighting some recent advances and offering some perspectives on future directions.
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Affiliation(s)
- Ashley B Strickland
- Division of Immunology, Virginia-Maryland College of Veterinary Medicine and Maryland Pathogen Research Institute, University of Maryland, College Park, MD, USA.
| | - Meiqing Shi
- Division of Immunology, Virginia-Maryland College of Veterinary Medicine and Maryland Pathogen Research Institute, University of Maryland, College Park, MD, USA.
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11
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Bürgel PH, Marina CL, Saavedra PHV, Albuquerque P, de Oliveira SAM, Veloso Janior PHH, de Castro RA, Heyman HM, Coelho C, Cordero RJB, Casadevall A, Nosanchuk JD, Nakayasu ES, May RC, Tavares AH, Bocca AL. Cryptococcus neoformans Secretes Small Molecules That Inhibit IL-1β Inflammasome-Dependent Secretion. Mediators Inflamm 2020; 2020:3412763. [PMID: 33380899 DOI: 10.1155/2020/3412763] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 10/22/2020] [Accepted: 11/04/2020] [Indexed: 01/22/2023] Open
Abstract
Cryptococcus neoformans is an encapsulated yeast that causes disease mainly in immunosuppressed hosts. It is considered a facultative intracellular pathogen because of its capacity to survive and replicate inside phagocytes, especially macrophages. This ability is heavily dependent on various virulence factors, particularly the glucuronoxylomannan (GXM) component of the polysaccharide capsule. Inflammasome activation in phagocytes is usually protective against fungal infections, including cryptococcosis. Nevertheless, recognition of C. neoformans by inflammasome receptors requires specific changes in morphology or the opsonization of the yeast, impairing proper inflammasome function. In this context, we analyzed the impact of molecules secreted by C. neoformans B3501 strain and its acapsular mutant Δcap67 in inflammasome activation in an in vitro model. Our results showed that conditioned media derived from B3501 was capable of inhibiting inflammasome-dependent events (i.e., IL-1β secretion and LDH release via pyroptosis) more strongly than conditioned media from Δcap67, regardless of GXM presence. We also demonstrated that macrophages treated with conditioned media were less responsive against infection with the virulent strain H99, exhibiting lower rates of phagocytosis, increased fungal burdens, and enhanced vomocytosis. Moreover, we showed that the aromatic metabolite DL-Indole-3-lactic acid (ILA) and DL-p-Hydroxyphenyllactic acid (HPLA) were present in B3501's conditioned media and that ILA alone or with HPLA is involved in the regulation of inflammasome activation by C. neoformans. These results were confirmed by in vivo experiments, where exposure to conditioned media led to higher fungal burdens in Acanthamoeba castellanii culture as well as in higher fungal loads in the lungs of infected mice. Overall, the results presented show that conditioned media from a wild-type strain can inhibit a vital recognition pathway and subsequent fungicidal functions of macrophages, contributing to fungal survival in vitro and in vivo and suggesting that secretion of aromatic metabolites, such as ILA, during cryptococcal infections fundamentally impacts pathogenesis.
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12
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Gaylord EA, Choy HL, Doering TL. Dangerous Liaisons: Interactions of Cryptococcus neoformans with Host Phagocytes. Pathogens 2020; 9:E891. [PMID: 33121050 PMCID: PMC7692806 DOI: 10.3390/pathogens9110891] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2020] [Revised: 10/22/2020] [Accepted: 10/25/2020] [Indexed: 02/07/2023] Open
Abstract
Cryptococcus neoformans is an opportunistic fungal pathogen and a leading cause of death in immunocompromised individuals. The interactions of this yeast with host phagocytes are critical to disease outcome, and C. neoformans is equipped with an array of factors to modulate these processes. Cryptococcal infection begins with the deposition of infectious particles into the lungs, where the fungal cells deploy various antiphagocytic factors to resist internalization by host cells. If the cryptococci are still engulfed, they can survive and proliferate within host cells by modulating the phagolysosome environment in which they reside. Lastly, cryptococcal cells may escape from phagocytes by host cell lysis, nonlytic exocytosis, or lateral cell-to-cell transfer. The interactions between C. neoformans and host phagocytes also influence the dissemination of this pathogen to the brain, where it may cross the blood-brain barrier and cause an often-fatal meningoencephalitis. In this review, we highlight key cryptococcal factors involved in various stages of cryptococcal-host interaction and pathogenesis.
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Affiliation(s)
| | | | - Tamara L. Doering
- Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, MO 63110, USA; (E.A.G.); (H.L.C.)
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13
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Scherer AK, Blair BA, Park J, Seman BG, Kelley JB, Wheeler RT. Redundant Trojan horse and endothelial-circulatory mechanisms for host-mediated spread of Candida albicans yeast. PLoS Pathog 2020; 16:e1008414. [PMID: 32776983 PMCID: PMC7447064 DOI: 10.1371/journal.ppat.1008414] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 08/25/2020] [Accepted: 06/03/2020] [Indexed: 12/18/2022] Open
Abstract
The host innate immune system has developed elegant processes for the detection and clearance of invasive fungal pathogens. These strategies may also aid in the spread of pathogens in vivo, although technical limitations have previously hindered our ability to view the host innate immune and endothelial cells to probe their roles in spreading disease. Here, we have leveraged zebrafish larvae as a model to view the interactions of these host processes with the fungal pathogen Candida albicans in vivo. We examined three potential host-mediated mechanisms of fungal spread: movement inside phagocytes in a "Trojan Horse" mechanism, inflammation-assisted spread, and endothelial barrier passage. Utilizing both chemical and genetic tools, we systematically tested the loss of neutrophils and macrophages and the loss of blood flow on yeast cell spread. Both neutrophils and macrophages respond to yeast-locked and wild type C. albicans in our model and time-lapse imaging revealed that macrophages can support yeast spread in a "Trojan Horse" mechanism. Surprisingly, loss of immune cells or inflammation does not alter dissemination dynamics. On the other hand, when blood flow is blocked, yeast can cross into blood vessels but they are limited in how far they travel. Blockade of both phagocytes and circulation reduces rates of dissemination and significantly limits the distance of fungal spread from the infection site. Together, this data suggests a redundant two-step process whereby (1) yeast cross the endothelium inside phagocytes or via direct uptake, and then (2) they utilize blood flow or phagocytes to travel to distant sites.
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Affiliation(s)
- Allison K. Scherer
- Department of Molecular & Biomedical Sciences, University of Maine, Orono, Maine, United States of America
| | - Bailey A. Blair
- Department of Molecular & Biomedical Sciences, University of Maine, Orono, Maine, United States of America
- Graduate School of Biomedical Sciences, University of Maine, Orono, Maine, United States of America
| | - Jieun Park
- Department of Cell Biology and Department of Pharmacology and Cancer Biology, Duke University, Durham, North Carolina, United States of America
| | - Brittany G. Seman
- Department of Molecular & Biomedical Sciences, University of Maine, Orono, Maine, United States of America
| | - Joshua B. Kelley
- Department of Molecular & Biomedical Sciences, University of Maine, Orono, Maine, United States of America
- Graduate School of Biomedical Sciences, University of Maine, Orono, Maine, United States of America
| | - Robert T. Wheeler
- Department of Molecular & Biomedical Sciences, University of Maine, Orono, Maine, United States of America
- Graduate School of Biomedical Sciences, University of Maine, Orono, Maine, United States of America
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14
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Abstract
Macrophages are a key cell type in innate immunity. Years of in vitro cell culture studies have unraveled myriad macrophage pathways that combat pathogens and demonstrated how pathogen effectors subvert these mechanisms. However, in vitro cell culture studies may not accurately reflect how macrophages fit into the context of an innate immune response in whole animals with multiple cell types and tissues. Larval zebrafish have emerged as an intermediate model of innate immunity and host-pathogen interactions to bridge the gap between cell culture studies and mammalian models. These organisms possess an innate immune system largely conserved with that of humans and allow state-of-the-art genetic and imaging techniques, all in the context of an intact organism. Using larval zebrafish, researchers are elucidating the function of macrophages in response to many different infections, including both bacterial and fungal pathogens. The goal of this review is to highlight studies in zebrafish that utilized live-imaging techniques to analyze macrophage activities in response to pathogens. Recent studies have explored the roles of specific pathways and mechanisms in macrophage killing ability, explored how pathogens subvert these responses, identified subsets of macrophages with differential microbicidal activities, and implicated macrophages as an intracellular niche for pathogen survival and trafficking. Research using this model continues to advance our understanding of how macrophages, and specific pathways inside these cells, fit into complex multicellular innate immune responses in vivo, providing important information on how pathogens evade these pathways and how we can exploit them for development of treatments against microbial infections.
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15
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Nelson BN, Hawkins AN, Wozniak KL. Pulmonary Macrophage and Dendritic Cell Responses to Cryptococcus neoformans. Front Cell Infect Microbiol 2020; 10:37. [PMID: 32117810 PMCID: PMC7026008 DOI: 10.3389/fcimb.2020.00037] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Accepted: 01/20/2020] [Indexed: 12/12/2022] Open
Abstract
The fungal pathogen Cryptococcus neoformans can cause life-threatening infections in immune compromised individuals. This pathogen is typically acquired via inhalation, and enters the respiratory tract. Innate immune cells such as macrophages and dendritic cells (DCs) are the first host cells that encounter C. neoformans, and the interactions between Cryptococcus and innate immune cells play a critical role in the progression of disease. Cryptococcus possesses several virulence factors and evasion strategies to prevent its killing and destruction by pulmonary phagocytes, but these phagocytic cells can also contribute to anti-cryptococcal responses. This review will focus on the interactions between Cryptococcus and primary macrophages and dendritic cells (DCs), dealing specifically with the cryptococcal/pulmonary cell interface.
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Affiliation(s)
- Benjamin N Nelson
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, United States
| | - Ashlee N Hawkins
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, United States
| | - Karen L Wozniak
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, United States
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16
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Abstract
Macrophages are well known for their phagocytic activity and their role in innate immune responses. Macrophages eat non-self particles, via a variety of mechanisms, and typically break down internalized cargo into small macromolecules. However, some pathogenic agents have the ability to evade this endosomal degradation through a nonlytic exocytosis process termed vomocytosis. Macrophages are well known for their phagocytic activity and their role in innate immune responses. Macrophages eat non-self particles, via a variety of mechanisms, and typically break down internalized cargo into small macromolecules. However, some pathogenic agents have the ability to evade this endosomal degradation through a nonlytic exocytosis process termed vomocytosis. This phenomenon has been most often studied for Cryptococcus neoformans, a yeast that causes roughly 180,000 deaths per year, primarily in immunocompromised (e.g., human immunodeficiency virus [HIV]) patients. Existing dogma purports that vomocytosis involves distinctive cellular pathways and intracellular physicochemical cues in the host cell during phagosomal maturation. Moreover, it has been observed that the immunological state of the individual and macrophage phenotype affect vomocytosis outcomes. Here we compile the current knowledge on the factors (with respect to the phagocytic cell) that promote vomocytosis of C. neoformans from macrophages.
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17
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Abstract
Vomocytosis, or nonlytic exocytosis, has been reported for Cryptococcus neoformans since 2006. Since then, the repertoire of vomocytosing pathogens and host cells has increased and so have the molecular components linked to vomocytosis occurrence. Nonetheless, the mechanism underlying this phenomenon, whether it is triggered by the host or the pathogen, and how it affects disease progression are still unresolved. This review contains a summary of the main findings regarding vomocytosis and the outstanding questions puzzling scientists to this day.
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Affiliation(s)
- Paula I Seoane
- Laboratory of Host and Pathogen Interactions, Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Birmingham, UK
| | - Robin C May
- Laboratory of Host and Pathogen Interactions, Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Birmingham, UK
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18
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Lundie RJ, Helbig KJ, Pearson JS, Fairfax KA. Fluorescent antibiotics, vomocytosis, vaccine candidates and the inflammasome. Clin Transl Immunology 2019; 8:e01083. [PMID: 31700626 PMCID: PMC6823609 DOI: 10.1002/cti2.1083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Affiliation(s)
- Rachel J Lundie
- The Walter and Eliza Hall Institute of Medical Research Parkville, Melbourne VIC 3052 Australia
| | - Karla J Helbig
- Department of Physiology, Anatomy and Microbiology School of Life Sciences La Trobe University Bundoora VIC 3086 Australia
| | - Jaclyn S Pearson
- Centre for Innate Immunity and Infectious Diseases Hudson Institute of Medical Research Clayton VIC 3168 Australia
| | - Kirsten A Fairfax
- The Walter and Eliza Hall Institute of Medical Research Parkville, Melbourne VIC 3052 Australia.,Department of Medical Biology The University of Melbourne Parkville VIC 3010 Australia.,School of Medicine Menzies Research Institute Tasmania University of Tasmania Hobart TAS 7000 Australia
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19
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Rudman J, Evans RJ, Johnston SA. Are macrophages the heroes or villains during cryptococcosis? Fungal Genet Biol 2019; 132:103261. [DOI: 10.1016/j.fgb.2019.103261] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Revised: 08/06/2019] [Accepted: 08/06/2019] [Indexed: 10/26/2022]
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20
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Denham ST, Wambaugh MA, Brown JCS. How Environmental Fungi Cause a Range of Clinical Outcomes in Susceptible Hosts. J Mol Biol 2019; 431:2982-3009. [PMID: 31078554 PMCID: PMC6646061 DOI: 10.1016/j.jmb.2019.05.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Revised: 04/18/2019] [Accepted: 05/01/2019] [Indexed: 12/11/2022]
Abstract
Environmental fungi are globally ubiquitous and human exposure is near universal. However, relatively few fungal species are capable of infecting humans, and among fungi, few exposure events lead to severe systemic infections. Systemic infections have mortality rates of up to 90%, cost the US healthcare system $7.2 billion annually, and are typically associated with immunocompromised patients. Despite this reputation, exposure to environmental fungi results in a range of outcomes, from asymptomatic latent infections to severe systemic infection. Here we discuss different exposure outcomes for five major fungal pathogens: Aspergillus, Blastomyces, Coccidioides, Cryptococcus, and Histoplasma species. These fungi include a mold, a budding yeast, and thermal dimorphic fungi. All of these species must adapt to dramatically changing environments over the course of disease. These dynamic environments include the human lung, which is the first exposure site for these organisms. Fungi must defend themselves against host immune cells while germinating and growing, which risks further exposing microbe-associated molecular patterns to the host. We discuss immune evasion strategies during early infection, from disruption of host immune cells to major changes in fungal cell morphology.
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Affiliation(s)
- Steven T Denham
- Division of Microbiology and Immunology, Pathology Department, University of Utah School of Medicine, Salt Lake City, UT 84132, USA
| | - Morgan A Wambaugh
- Division of Microbiology and Immunology, Pathology Department, University of Utah School of Medicine, Salt Lake City, UT 84132, USA
| | - Jessica C S Brown
- Division of Microbiology and Immunology, Pathology Department, University of Utah School of Medicine, Salt Lake City, UT 84132, USA.
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21
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Affiliation(s)
- Nilesh Kumar Sharma
- Cancer & Translational Research Lab, Dr DY Patil Biotechnology & Bioinformatics Institute, Dr DY Patil Vidyapeeth, Pune 411033, Maharashtra, India
| | - Sachin C Sarode
- Department of Oral Pathology & Microbiology, Dr DY Patil Dental College & Hospital, Dr DY Patil Vidyapeeth, Sant Tukaram Nagar, Pimpri, Pune, India
| | - Gargi S Sarode
- Department of Oral Pathology & Microbiology, Dr DY Patil Dental College & Hospital, Dr DY Patil Vidyapeeth, Sant Tukaram Nagar, Pimpri, Pune, India
| | - Shankargouda Patil
- Department of Maxillofacial Surgery & Diagnostic Sciences, Division of Oral Pathology, College of Dentistry, Jazan University, Jazan, Saudi Arabia
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22
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Evans RJ, Pline K, Loynes CA, Needs S, Aldrovandi M, Tiefenbach J, Bielska E, Rubino RE, Nicol CJ, May RC, Krause HM, O’Donnell VB, Renshaw SA, Johnston SA. 15-keto-prostaglandin E2 activates host peroxisome proliferator-activated receptor gamma (PPAR-γ) to promote Cryptococcus neoformans growth during infection. PLoS Pathog 2019; 15:e1007597. [PMID: 30921435 PMCID: PMC6438442 DOI: 10.1371/journal.ppat.1007597] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Accepted: 01/25/2019] [Indexed: 12/19/2022] Open
Abstract
Cryptococcus neoformans is one of the leading causes of invasive fungal infection in humans worldwide. C. neoformans uses macrophages as a proliferative niche to increase infective burden and avoid immune surveillance. However, the specific mechanisms by which C. neoformans manipulates host immunity to promote its growth during infection remain ill-defined. Here we demonstrate that eicosanoid lipid mediators manipulated and/or produced by C. neoformans play a key role in regulating pathogenesis. C. neoformans is known to secrete several eicosanoids that are highly similar to those found in vertebrate hosts. Using eicosanoid deficient cryptococcal mutants Δplb1 and Δlac1, we demonstrate that prostaglandin E2 is required by C. neoformans for proliferation within macrophages and in vivo during infection. Genetic and pharmacological disruption of host PGE2 synthesis is not required for promotion of cryptococcal growth by eicosanoid production. We find that PGE2 must be dehydrogenated into 15-keto-PGE2 to promote fungal growth, a finding that implicated the host nuclear receptor PPAR-γ. C. neoformans infection of macrophages activates host PPAR-γ and its inhibition is sufficient to abrogate the effect of 15-keto-PGE2 in promoting fungal growth during infection. Thus, we describe the first mechanism of reliance on pathogen-derived eicosanoids in fungal pathogenesis and the specific role of 15-keto-PGE2 and host PPAR-γ in cryptococcosis. Cryptococcus neoformans is an opportunistic fungal pathogen that is responsible for significant numbers of deaths in the immunocompromised population worldwide. Here we address whether eicosanoids produced by C. neoformans manipulate host innate immune cells during infection. Cryptococcus neoformans produces several eicosanoids that are notable for their similarity to vertebrate eicosanoids, it is therefore possible that fungal-derived eicosanoids may provoke physiological effects in the host. Using a combination of in vitro and in vivo infection models we identify a specific eicosanoid species—prostaglandin E2 –that is required by C. neoformans for growth during infection. We subsequently show that prostaglandin E2 must be converted to 15-keto-prostaglandin E2 within the host before it has these effects. Furthermore, we find that prostaglandin E2/15-keto-prostaglandin E2 mediated virulence is via activation of host PPAR-γ –an intracellular eicosanoid receptor known to interact with 15-keto-PGE2.
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Affiliation(s)
- Robert J. Evans
- Bateson Centre, Firth Court, University of Sheffield, Sheffield, South Yorkshire, United Kingdom
- Department of Infection, Immunity and Cardiovascular Disease, Medical School, University of Sheffield, Sheffield, South Yorkshire, United Kingdom
| | - Katherine Pline
- Bateson Centre, Firth Court, University of Sheffield, Sheffield, South Yorkshire, United Kingdom
- Department of Infection, Immunity and Cardiovascular Disease, Medical School, University of Sheffield, Sheffield, South Yorkshire, United Kingdom
| | - Catherine A. Loynes
- Bateson Centre, Firth Court, University of Sheffield, Sheffield, South Yorkshire, United Kingdom
- Department of Infection, Immunity and Cardiovascular Disease, Medical School, University of Sheffield, Sheffield, South Yorkshire, United Kingdom
| | - Sarah Needs
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Birmingham, West Midlands, United Kingdom
| | - Maceler Aldrovandi
- Systems Immunity Research Institute, and Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, South Glamorgan, United Kingdom
| | - Jens Tiefenbach
- Banting and Best Department of Medical Research, The Terrence Donnelly Centre for Cellular and Biomolecular Research (CCBR), University of Toronto, Toronto, Ontario, Canada
- InDanio Bioscience Inc., Toronto, Ontario, Canada
| | - Ewa Bielska
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Birmingham, West Midlands, United Kingdom
| | - Rachel E. Rubino
- Department of Pathology and Molecular Medicine, Queen's University, Kingston, Ontario, Canada
| | - Christopher J. Nicol
- Department of Pathology and Molecular Medicine, Queen's University, Kingston, Ontario, Canada
| | - Robin C. May
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Birmingham, West Midlands, United Kingdom
| | - Henry M. Krause
- Banting and Best Department of Medical Research, The Terrence Donnelly Centre for Cellular and Biomolecular Research (CCBR), University of Toronto, Toronto, Ontario, Canada
- InDanio Bioscience Inc., Toronto, Ontario, Canada
| | - Valerie B. O’Donnell
- Systems Immunity Research Institute, and Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, South Glamorgan, United Kingdom
| | - Stephen A. Renshaw
- Bateson Centre, Firth Court, University of Sheffield, Sheffield, South Yorkshire, United Kingdom
- Department of Infection, Immunity and Cardiovascular Disease, Medical School, University of Sheffield, Sheffield, South Yorkshire, United Kingdom
| | - Simon A. Johnston
- Bateson Centre, Firth Court, University of Sheffield, Sheffield, South Yorkshire, United Kingdom
- Department of Infection, Immunity and Cardiovascular Disease, Medical School, University of Sheffield, Sheffield, South Yorkshire, United Kingdom
- * E-mail:
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23
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Visser JG, Van Staden ADP, Smith C. Harnessing Macrophages for Controlled-Release Drug Delivery: Lessons From Microbes. Front Pharmacol 2019; 10:22. [PMID: 30740053 PMCID: PMC6355695 DOI: 10.3389/fphar.2019.00022] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Accepted: 01/09/2019] [Indexed: 01/15/2023] Open
Abstract
With the effectiveness of therapeutic agents ever decreasing and the increased incidence of multi-drug resistant pathogens, there is a clear need for administration of more potent, potentially more toxic, drugs. Alternatively, biopharmaceuticals may hold potential but require specialized protection from premature in vivo degradation. Thus, a paralleled need for specialized drug delivery systems has arisen. Although cell-mediated drug delivery is not a completely novel concept, the few applications described to date are not yet ready for in vivo application, for various reasons such as drug-induced carrier cell death, limited control over the site and timing of drug release and/or drug degradation by the host immune system. Here, we present our hypothesis for a new drug delivery system, which aims to negate these limitations. We propose transport of nanoparticle-encapsulated drugs inside autologous macrophages polarized to M1 phenotype for high mobility and treated to induce transient phagosome maturation arrest. In addition, we propose a significant shift of existing paradigms in the study of host-microbe interactions, in order to study microbial host immune evasion and dissemination patterns for their therapeutic utilization in the context of drug delivery. We describe a system in which microbial strategies may be adopted to facilitate absolute control over drug delivery, and without sacrificing the host carrier cells. We provide a comprehensive summary of the lessons we can learn from microbes in the context of drug delivery and discuss their feasibility for in vivo therapeutic application. We then describe our proposed "synthetic microbe drug delivery system" in detail. In our opinion, this multidisciplinary approach may hold the solution to effective, controlled drug delivery.
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Affiliation(s)
- Johan Georg Visser
- Department of Physiological Sciences, Stellenbosch University, Matieland, South Africa
| | | | - Carine Smith
- Department of Physiological Sciences, Stellenbosch University, Matieland, South Africa
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24
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Abstract
Host cell exit is a critical step in the life-cycle of intracellular pathogens, intimately linked to barrier penetration, tissue dissemination, inflammation, and pathogen transmission. Like cell invasion and intracellular survival, host cell exit represents a well-regulated program that has evolved during host-pathogen co-evolution and that relies on the dynamic and intricate interplay between multiple host and microbial factors. Three distinct pathways of host cell exit have been identified that are employed by three different taxa of intracellular pathogens, bacteria, fungi and protozoa, namely (i) the initiation of programmed cell death, (ii) the active breaching of host cellderived membranes, and (iii) the induced membrane-dependent exit without host cell lysis. Strikingly, an increasing number of studies show that the majority of intracellular pathogens utilize more than one of these strategies, dependent on life-cycle stage, environmental factors and/or host cell type. This review summarizes the diverse exit strategies of intracellular-living bacterial, fungal and protozoan pathogens and discusses the convergently evolved commonalities as well as system-specific variations thereof. Key microbial molecules involved in host cell exit are highlighted and discussed as potential targets for future interventional approaches.
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Affiliation(s)
- Antje Flieger
- Division of Enteropathogenic Bacteria and Legionella, Robert Koch Institute, Wernigerode, Germany
| | | | - Georg Häcker
- Institute of Medical Microbiology and Hygiene, Medical Center - University of Freiburg, Germany
| | - Mathias W Hornef
- Institute of Medical Microbiology, RWTH Aachen University Hospital, Germany
| | - Gabriele Pradel
- Division of Cellular and Applied Infection Biology, Institute of Biology II, RWTH Aachen University, Germany
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25
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Francis EA, Heinrich V. Mechanistic Understanding of Single-Cell Behavior is Essential for Transformative Advances in Biomedicine. Yale J Biol Med 2018; 91:279-289. [PMID: 30258315 PMCID: PMC6153630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Most current efforts to advance medical technology proceed along one of two tracks. The first is dedicated to the improvement of clinical tasks through the incremental refinement of medical instruments. The second comprises engineering endeavors to support basic science studies that often only remotely relate to human medicine. Here we survey emerging research approaches that aim to populate the sprawling frontier between these tracks. We focus on interdisciplinary single-live-cell techniques that have overcome limitations of traditional biological methods to successfully address vital questions about medically relevant cellular behavior. Most of the presented case studies are based on the controlled manipulation of nonadherent human immune cells using one or more micropipettes. The included studies have (i) examined one-on-one encounters of immune cells with real or model pathogens, (ii) assessed the physiological role of the expandable surface area of immune cells, and (iii) started to dissect the spatiotemporal organization of signaling processes within these cells. The unique aptitude of such single-live-cell studies to fill conspicuous gaps in our quantitative understanding of medically relevant cause-effect relationships provides a sound basis for new insights that will inform and drive future biomedical innovation.
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Affiliation(s)
| | - Volkmar Heinrich
- To whom all correspondence should be addressed: Volkmar Heinrich, Department of Biomedical Engineering, University of California, Davis, 451 Health Sciences Drive, Davis, CA 95616; Tel: 530-754-6644,
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26
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Van Dijck P, Sjollema J, Cammue BPA, Lagrou K, Berman J, d’Enfert C, Andes DR, Arendrup MC, Brakhage AA, Calderone R, Cantón E, Coenye T, Cos P, Cowen LE, Edgerton M, Espinel-Ingroff A, Filler SG, Ghannoum M, Gow NA, Haas H, Jabra-Rizk MA, Johnson EM, Lockhart SR, Lopez-Ribot JL, Maertens J, Munro CA, Nett JE, Nobile CJ, Pfaller MA, Ramage G, Sanglard D, Sanguinetti M, Spriet I, Verweij PE, Warris A, Wauters J, Yeaman MR, Zaat SA, Thevissen K. Methodologies for in vitro and in vivo evaluation of efficacy of antifungal and antibiofilm agents and surface coatings against fungal biofilms. Microb Cell 2018; 5:300-326. [PMID: 29992128 PMCID: PMC6035839 DOI: 10.15698/mic2018.07.638] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 05/24/2018] [Indexed: 12/13/2022]
Abstract
Unlike superficial fungal infections of the skin and nails, which are the most common fungal diseases in humans, invasive fungal infections carry high morbidity and mortality, particularly those associated with biofilm formation on indwelling medical devices. Therapeutic management of these complex diseases is often complicated by the rise in resistance to the commonly used antifungal agents. Therefore, the availability of accurate susceptibility testing methods for determining antifungal resistance, as well as discovery of novel antifungal and antibiofilm agents, are key priorities in medical mycology research. To direct advancements in this field, here we present an overview of the methods currently available for determining (i) the susceptibility or resistance of fungal isolates or biofilms to antifungal or antibiofilm compounds and compound combinations; (ii) the in vivo efficacy of antifungal and antibiofilm compounds and compound combinations; and (iii) the in vitro and in vivo performance of anti-infective coatings and materials to prevent fungal biofilm-based infections.
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Affiliation(s)
- Patrick Van Dijck
- VIB-KU Leuven Center for Microbiology, Leuven, Belgium
- KU Leuven Laboratory of Molecular Cell Biology, Leuven, Belgium
| | - Jelmer Sjollema
- University of Groningen, University Medical Center Groningen, Department of BioMedical Engineering, Groningen, The Netherlands
| | - Bruno P. A. Cammue
- Centre for Microbial and Plant Genetics, KU Leuven, Leuven, Belgium
- Department of Plant Systems Biology, VIB, Ghent, Belgium
| | - Katrien Lagrou
- Department of Microbiology and Immunology, KU Leuven, Leuven, Belgium
- Clinical Department of Laboratory Medicine and National Reference Center for Mycosis, UZ Leuven, Belgium
| | - Judith Berman
- School of Molecular Cell Biology and Biotechnology, Faculty of Life Sciences, Tel Aviv University, Ramat Aviv, Israel
| | - Christophe d’Enfert
- Institut Pasteur, INRA, Unité Biologie et Pathogénicité Fongiques, Paris, France
| | - David R. Andes
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Department of Medicine, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Maiken C. Arendrup
- Unit of Mycology, Statens Serum Institut, Copenhagen, Denmark
- Department of Clinical Microbiology, Rigshospitalet, Copenhagen, Denmark
- Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Axel A. Brakhage
- Leibniz Institute for Natural Product Research and Infection Biology - Hans Knoell Institute (HKI), Dept. Microbiology and Molecular Biology, Friedrich Schiller University Jena, Institute of Microbiology, Jena, Germany
| | - Richard Calderone
- Department of Microbiology & Immunology, Georgetown University Medical Center, Washington DC, USA
| | - Emilia Cantón
- Severe Infection Research Group: Medical Research Institute La Fe (IISLaFe), Valencia, Spain
| | - Tom Coenye
- Laboratory of Pharmaceutical Microbiology, Ghent University, Ghent, Belgium
- ESCMID Study Group for Biofilms, Switzerland
| | - Paul Cos
- Laboratory for Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, Belgium
| | - Leah E. Cowen
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Mira Edgerton
- Department of Oral Biology, School of Dental Medicine, University at Buffalo, Buffalo, NY USA
| | | | - Scott G. Filler
- Division of Infectious Diseases, Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, Torrance, CA, USA
| | - Mahmoud Ghannoum
- Center for Medical Mycology, Department of Dermatology, University Hospitals Cleveland Medical Center and Case Western Re-serve University, Cleveland, OH, USA
| | - Neil A.R. Gow
- MRC Centre for Medical Mycology, Institute of Medical Sciences, University of Aberdeen, Aberdeen, UK
| | - Hubertus Haas
- Biocenter - Division of Molecular Biology, Medical University Innsbruck, Innsbruck, Austria
| | - Mary Ann Jabra-Rizk
- Department of Oncology and Diagnostic Sciences, School of Dentistry; Department of Microbiology and Immunology, School of Medicine, University of Maryland, Baltimore, USA
| | - Elizabeth M. Johnson
- National Infection Service, Public Health England, Mycology Reference Laboratory, Bristol, UK
| | | | | | - Johan Maertens
- Department of Microbiology and Immunology, KU Leuven, Leuven, Belgium and Clinical Department of Haematology, UZ Leuven, Leuven, Belgium
| | - Carol A. Munro
- MRC Centre for Medical Mycology, Institute of Medical Sciences, University of Aberdeen, Aberdeen, UK
| | - Jeniel E. Nett
- University of Wisconsin-Madison, Departments of Medicine and Medical Microbiology & Immunology, Madison, WI, USA
| | - Clarissa J. Nobile
- Department of Molecular and Cell Biology, School of Natural Sciences, University of California, Merced, Merced, USA
| | - Michael A. Pfaller
- Departments of Pathology and Epidemiology, University of Iowa, Iowa, USA
- JMI Laboratories, North Liberty, Iowa, USA
| | - Gordon Ramage
- ESCMID Study Group for Biofilms, Switzerland
- College of Medical, Veterinary and Life Sciences, University of Glasgow, UK
| | - Dominique Sanglard
- Institute of Microbiology, University of Lausanne and University Hospital, CH-1011 Lausanne
| | - Maurizio Sanguinetti
- Institute of Microbiology, Università Cattolica del Sacro Cuore, IRCCS-Fondazione Policlinico "Agostino Gemelli", Rome, Italy
| | - Isabel Spriet
- Pharmacy Dpt, University Hospitals Leuven and Clinical Pharmacology and Pharmacotherapy, Dpt. of Pharmaceutical and Pharma-cological Sciences, KU Leuven, Belgium
| | - Paul E. Verweij
- Center of Expertise in Mycology Radboudumc/CWZ, Radboud University Medical Center, Nijmegen, the Netherlands (omit "Nijmegen" in Radboud University Medical Center)
| | - Adilia Warris
- MRC Centre for Medical Mycology, Aberdeen Fungal Group, University of Aberdeen, Foresterhill, Aberdeen, UK
| | - Joost Wauters
- KU Leuven-University of Leuven, University Hospitals Leuven, Department of General Internal Medicine, Herestraat 49, B-3000 Leuven, Belgium
| | - Michael R. Yeaman
- Geffen School of Medicine at the University of California, Los Angeles, Divisions of Molecular Medicine & Infectious Diseases, Har-bor-UCLA Medical Center, LABioMed at Harbor-UCLA Medical Center
| | - Sebastian A.J. Zaat
- Department of Medical Microbiology, Amsterdam Infection and Immunity Institute, Academic Medical Center, University of Am-sterdam, Netherlands
| | - Karin Thevissen
- Centre for Microbial and Plant Genetics, KU Leuven, Leuven, Belgium
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Fu MS, Coelho C, De Leon-Rodriguez CM, Rossi DCP, Camacho E, Jung EH, Kulkarni M, Casadevall A. Cryptococcus neoformans urease affects the outcome of intracellular pathogenesis by modulating phagolysosomal pH. PLoS Pathog 2018; 14:e1007144. [PMID: 29906292 PMCID: PMC6021110 DOI: 10.1371/journal.ppat.1007144] [Citation(s) in RCA: 71] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 06/27/2018] [Accepted: 06/05/2018] [Indexed: 01/22/2023] Open
Abstract
Cryptococcus neoformans is a facultative intracellular pathogen and its interaction with macrophages is a key event determining the outcome of infection. Urease is a major virulence factor in C. neoformans but its role during macrophage interaction has not been characterized. Consequently, we analyzed the effect of urease on fungal-macrophage interaction using wild-type, urease-deficient and urease-complemented strains of C. neoformans. The frequency of non-lytic exocytosis events was reduced in the absence of urease. Urease-positive C. neoformans manifested reduced and delayed intracellular replication with fewer macrophages displaying phagolysosomal membrane permeabilization. The production of urease was associated with increased phagolysosomal pH, which in turn reduced growth of urease-positive C. neoformans inside macrophages. Interestingly, the ure1 mutant strain grew slower in fungal growth medium which was buffered to neutral pH (pH 7.4). Mice inoculated with macrophages carrying urease-deficient C. neoformans had lower fungal burden in the brain than mice infected with macrophages carrying wild-type strain. In contrast, the absence of urease did not affect survival of yeast when interacting with amoebae. Because of the inability of the urease deletion mutant to grow on urea as a sole nitrogen source, we hypothesize urease plays a nutritional role involved in nitrogen acquisition in the environment. Taken together, our data demonstrate that urease affects fitness within the mammalian phagosome, promoting non-lytic exocytosis while delaying intracellular replication and thus reducing phagolysosomal membrane damage, events that could facilitate cryptococcal dissemination when transported inside macrophages. This system provides an example where an enzyme involved in nutrient acquisition modulates virulence during mammalian infection.
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Affiliation(s)
- Man Shun Fu
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Carolina Coelho
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Carlos M. De Leon-Rodriguez
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Diego C. P. Rossi
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Emma Camacho
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Eric H. Jung
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Madhura Kulkarni
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Arturo Casadevall
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, United States of America
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Watkins RA, Andrews A, Wynn C, Barisch C, King JS, Johnston SA. Cryptococcus neoformans Escape From Dictyostelium Amoeba by Both WASH-Mediated Constitutive Exocytosis and Vomocytosis. Front Cell Infect Microbiol 2018; 8:108. [PMID: 29686972 PMCID: PMC5900056 DOI: 10.3389/fcimb.2018.00108] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Accepted: 03/19/2018] [Indexed: 01/01/2023] Open
Abstract
Cryptococcus neoformans is an environmental yeast that can cause opportunistic infections in humans. As infecting animals does not form part of its normal life-cycle, it has been proposed that the virulence traits that allow cryptococci to resist immune cells were selected through interactions with environmental phagocytes such as amoebae. Here, we investigate the interactions between C. neoformans and the social amoeba Dictyostelium discoideum. We show that like macrophages, D. discoideum is unable to kill C. neoformans upon phagocytosis. Despite this, we find that the yeast pass through the amoebae with an apparently normal phagocytic transit and are released alive by constitutive exocytosis after ~80 min. This is the canonical pathway in amoebae, used to dispose of indigestible material after nutrient extraction. Surprisingly however, we show that upon either genetic or pharmacological blockage of constitutive exocytosis, C. neoformans still escape from D. discoideum by a secondary mechanism. We demonstrate that constitutive exocytosis-independent egress is stochastic and actin-independent. This strongly resembles the non-lytic release of cryptococci by vomocytosis from macrophages, which do not perform constitutive exocytosis and normally retain phagocytosed material. Our data indicate that vomocytosis is functionally redundant for escape from amoebae, which thus may not be the primary driver for its evolutionary selection. Nonetheless, we show that vomocytosis of C. neoformans is mechanistically conserved in hosts ranging from amoebae to man, providing new avenues to understand this poorly-understood but important virulence mechanism.
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Affiliation(s)
- Rhys A. Watkins
- Bateson Centre, University of Sheffield, Sheffield, United Kingdom
- Department of Infection Immunity and Cardiovascular Disease, Medical School, University of Sheffield, Sheffield, United Kingdom
| | - Alexandre Andrews
- Bateson Centre, University of Sheffield, Sheffield, United Kingdom
- Department of Infection Immunity and Cardiovascular Disease, Medical School, University of Sheffield, Sheffield, United Kingdom
| | - Charlotte Wynn
- Bateson Centre, University of Sheffield, Sheffield, United Kingdom
- Department of Infection Immunity and Cardiovascular Disease, Medical School, University of Sheffield, Sheffield, United Kingdom
| | - Caroline Barisch
- Department of Biochemistry, Faculty of Science, University of Geneva, Geneva, Switzerland
| | - Jason S. King
- Bateson Centre, University of Sheffield, Sheffield, United Kingdom
- Department of Biomedical Sciences, University of Sheffield, Sheffield, United Kingdom
| | - Simon A. Johnston
- Bateson Centre, University of Sheffield, Sheffield, United Kingdom
- Department of Infection Immunity and Cardiovascular Disease, Medical School, University of Sheffield, Sheffield, United Kingdom
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29
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Garelnabi M, Taylor-Smith LM, Bielska E, Hall RA, Stones D, May RC. Quantifying donor-to-donor variation in macrophage responses to the human fungal pathogen Cryptococcus neoformans. PLoS One 2018; 13:e0194615. [PMID: 29596441 PMCID: PMC5875765 DOI: 10.1371/journal.pone.0194615] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Accepted: 03/06/2018] [Indexed: 12/31/2022] Open
Abstract
Cryptococcosis remains the leading cause of fungal meningitis worldwide, caused primarily by the pathogen Cryptococcus neoformans. Symptomatic cryptococcal infections typically affect immunocompromised patients. However, environmental exposure to cryptococcal spores is ubiquitous and most healthy individuals are thought to harbor infections from early childhood onwards that are either resolved, or become latent. Since macrophages are a key host cell for cryptococcal infection, we sought to quantify the extent of individual variation in this early phagocyte response within a small cohort of healthy volunteers with no reported immunocompromising conditions. We show that rates of both intracellular fungal proliferation and non-lytic expulsion (vomocytosis) are remarkably variable between individuals. However, we demonstrate that neither gender, in vitro host inflammatory cytokine profiles, nor polymorphisms in several key immune genes are responsible for this variation. Thus the data we present serve to quantify the natural variation in macrophage responses to this important human pathogen and will hopefully provide a useful "benchmark" for the research community.
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Affiliation(s)
- Mariam Garelnabi
- Institute of Microbiology & Infection and the School of Biosciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
| | - Leanne M. Taylor-Smith
- Institute of Microbiology & Infection and the School of Biosciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
| | - Ewa Bielska
- Institute of Microbiology & Infection and the School of Biosciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
| | - Rebecca A. Hall
- Institute of Microbiology & Infection and the School of Biosciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
| | - Daniel Stones
- Institute of Microbiology & Infection and the School of Biosciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
| | - Robin C. May
- Institute of Microbiology & Infection and the School of Biosciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
- * E-mail:
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30
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Denham ST, Brown JCS. Mechanisms of Pulmonary Escape and Dissemination by Cryptococcus neoformans. J Fungi (Basel) 2018; 4:E25. [PMID: 29463005 DOI: 10.3390/jof4010025] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 02/09/2018] [Accepted: 02/16/2018] [Indexed: 12/15/2022] Open
Abstract
Cryptococcus neoformans is a common environmental saprophyte and human fungal pathogen that primarily causes disease in immunocompromised individuals. Similar to many environmentally acquired human fungal pathogens, C. neoformans initiates infection in the lungs. However, the main driver of mortality is invasive cryptococcosis leading to fungal meningitis. After C. neoformans gains a foothold in the lungs, a critical early step in invasion is transversal of the respiratory epithelium. In this review, we summarize current knowledge relating to pulmonary escape. We focus on fungal factors that allow C. neoformans to disseminate from the lungs via intracellular and extracellular routes.
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31
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Affiliation(s)
- Darius Armstrong-James
- Fungal Pathogens Laboratory, National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Leon de Boer
- Fungal Pathogens Laboratory, National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Amelia Bercusson
- Fungal Pathogens Laboratory, National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Anand Shah
- Fungal Pathogens Laboratory, National Heart and Lung Institute, Imperial College London, London, United Kingdom
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32
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Drummond RA. Neuro-Immune Mechanisms of Anti-Cryptococcal Protection. J Fungi (Basel) 2017; 4:E4. [PMID: 29371497 DOI: 10.3390/jof4010004] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 12/10/2017] [Accepted: 12/23/2017] [Indexed: 12/15/2022] Open
Abstract
Cryptococcal meningitis (CM) is a life-threatening fungal disease affecting both immunosuppressed and immunocompetent people. The main causative agent of CM is Cryptococcus neoformans, a basidiomycete fungus prevalent in the environment. Our understanding of the immune mechanisms controlling C. neoformans growth within the central nervous system (CNS) is poor. However, there have been several recent advances in the field of neuroimmunology regarding how cells resident within the CNS, such as microglia and neurons, can participate in immune surveillance and control of infection. In this mini-review, the cells of the CNS are discussed with reference to what is currently known about how they control C. neoformans infection.
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33
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Häfner S. I love you Toxoplasma gondii. Microbes Infect 2018; 20:131-4. [PMID: 29248636 DOI: 10.1016/j.micinf.2017.11.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Accepted: 11/27/2017] [Indexed: 11/20/2022]
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Ballou ER, Johnston SA. The cause and effect of Cryptococcus interactions with the host. Curr Opin Microbiol 2017; 40:88-94. [PMID: 29154043 DOI: 10.1016/j.mib.2017.10.012] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Accepted: 10/18/2017] [Indexed: 12/12/2022]
Abstract
Upon Cryptococcus neoformans infection of the host lung, the fungus enters a nutrient poor environment and must adapt to a variety of host-specific stress conditions (temperature, nutrient limitation, pH, CO2). Fungal spores enter this milieu with limited nutritional reserves, germinate, and begin proliferating by budding as yeast. Although relatively little is known about the initial stages of infection, recent work has characterized changes that occur upon germination. This program and subsequent yeast-phase proliferation progress in a dynamic environment as host nutrient immunity responds to the infection via toxic accumulation or sequestration of essential micronutrients and innate immune cells are recruited to the site of infection. Adaptation to the host environment and evasion of the immune response through pathogenicity factor expression allows proliferation and dissemination to multiple sites throughout the body, including, most significantly for human disease, the central nervous system. Here we will discuss recent insights into mechanisms underlying C. neoformans interactions with the host during infection.
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Affiliation(s)
- Elizabeth R Ballou
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Simon A Johnston
- Department of Infection, Immunity and Cardiovascular disease, Medical School, University of Sheffield, UK; Bateson Centre, University of Sheffield, Sheffield, UK.
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Watkins RA, King JS, Johnston SA. Nutritional Requirements and Their Importance for Virulence of Pathogenic Cryptococcus Species. Microorganisms 2017; 5:E65. [PMID: 28974017 DOI: 10.3390/microorganisms5040065] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Revised: 09/27/2017] [Accepted: 09/27/2017] [Indexed: 12/12/2022] Open
Abstract
Cryptococcus sp. are basidiomycete yeasts which can be found widely, free-living in the environment. Interactions with natural predators, such as amoebae in the soil, are thought to have promoted the development of adaptations enabling the organism to survive inside human macrophages. Infection with Cryptococcus in humans occurs following inhalation of desiccated yeast cells or spore particles and may result in fatal meningoencephalitis. Human disease is caused almost exclusively by the Cryptococcus neoformans species complex, which predominantly infects immunocompromised patients, and the Cryptococcus gattii species complex, which is capable of infecting immunocompetent individuals. The nutritional requirements of Cryptococcus are critical for its virulence in animals. Cryptococcus has evolved a broad range of nutrient acquisition strategies, many if not most of which also appear to contribute to its virulence, enabling infection of animal hosts. In this review, we summarise the current understanding of nutritional requirements and acquisition in Cryptococcus and offer perspectives to its evolution as a significant pathogen of humans.
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