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Cardoso-Miguel MDRD, Bürgel PH, de Castro RJA, Marina CL, de Oliveira SA, Albuquerque P, Silva-Pereira I, Bocca AL, Tavares AH. Dectin-2 is critical for phagocyte function and resistance to Paracoccidioides brasiliensis in mice. Med Mycol 2023; 61:myad117. [PMID: 37960963 DOI: 10.1093/mmy/myad117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Revised: 08/11/2023] [Accepted: 11/11/2023] [Indexed: 11/15/2023] Open
Abstract
Germline-encoded pattern recognition receptors, particularly C-type lectin receptors (CLRs), are essential for phagocytes to sense invading fungal cells. Among CLRs, Dectin-2 (encoded by Clec4n) plays a critical role in the antifungal immune response as it recognizes high-mannose polysaccharides on the fungal cell wall, triggering phagocyte functional activities and ultimately determining adaptive responses. Here, we assessed the role of Dectin-2 on the course of primary Paracoccidioides brasiliensis systemic infection in mice with Dectin-2-targeted deletion. Paracoccidioides brasiliensis constitutes the principal etiologic agent of paracoccidioidomycosis, the most prominent invasive mycosis in Latin American countries. The deficiency of Dectin-2 resulted in shortened survival rates, high lung fungal burden, and increased lung pathology in mice infected with P. brasiliensis. Consistently, dendritic cells (DCs) from mice lacking Dectin-2 infected ex vivo with P. brasiliensis showed impaired secretion of several proinflammatory and regulatory cytokines, including TNF-α, IL-1β, IL-6, and IL-10. Additionally, when cocultured with splenic lymphocytes, DCs were less efficient in promoting a type 1 cytokine pattern secretion (i.e., IFN-γ). In macrophages, Dectin-2-mediated signaling was required to ensure phagocytosis and fungicidal activity associated with nitric oxide production. Overall, Dectin-2-mediated signaling is critical to promote host protection against P. brasiliensis infection, and its exploitation might lead to the development of new vaccines and immunotherapeutic approaches.
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Affiliation(s)
- Mariana de Resende Damas Cardoso-Miguel
- Graduate Program in Microbial Biology, Department of Cell Biology, Institute of Biological Sciences, University of Brasília, Brasília, DF, Brazil
- Department of Cell Biology, Laboratory of Applied Immunology, Institute of Biological Sciences, University of Brasília, Brasília, DF, Brazil
| | - Pedro Henrique Bürgel
- Graduate Program in Microbial Biology, Department of Cell Biology, Institute of Biological Sciences, University of Brasília, Brasília, DF, Brazil
- Department of Cell Biology, Laboratory of Applied Immunology, Institute of Biological Sciences, University of Brasília, Brasília, DF, Brazil
| | - Raffael Júnio Araújo de Castro
- Department of Cell Biology, Laboratory of Applied Immunology, Institute of Biological Sciences, University of Brasília, Brasília, DF, Brazil
| | - Clara Luna Marina
- Department of Cell Biology, Laboratory of Applied Immunology, Institute of Biological Sciences, University of Brasília, Brasília, DF, Brazil
| | - Stephan Alberto de Oliveira
- Department of Cell Biology, Laboratory of Applied Immunology, Institute of Biological Sciences, University of Brasília, Brasília, DF, Brazil
| | - Patrícia Albuquerque
- Graduate Program in Microbial Biology, Department of Cell Biology, Institute of Biological Sciences, University of Brasília, Brasília, DF, Brazil
- Department of Cell Biology, Laboratory of Molecular Biology of Pathogenic Fungi, University of Brasília, Brasília, DF, Brazil
- Laboratory of Microorganism, Faculty of Ceilândia, University of Brasília, Brasília, DF, Brazil
| | - Ildinete Silva-Pereira
- Department of Cell Biology, Laboratory of Molecular Biology of Pathogenic Fungi, University of Brasília, Brasília, DF, Brazil
| | - Anamélia Lorenzetti Bocca
- Department of Cell Biology, Laboratory of Applied Immunology, Institute of Biological Sciences, University of Brasília, Brasília, DF, Brazil
| | - Aldo Henrique Tavares
- Graduate Program in Microbial Biology, Department of Cell Biology, Institute of Biological Sciences, University of Brasília, Brasília, DF, Brazil
- Laboratory of Microorganism, Faculty of Ceilândia, University of Brasília, Brasília, DF, Brazil
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2
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Onyishi CU, Desanti GE, Wilkinson AL, Lara-Reyna S, Frickel EM, Fejer G, Christophe OD, Bryant CE, Mukhopadhyay S, Gordon S, May RC. Toll-like receptor 4 and macrophage scavenger receptor 1 crosstalk regulates phagocytosis of a fungal pathogen. Nat Commun 2023; 14:4895. [PMID: 37580395 PMCID: PMC10425417 DOI: 10.1038/s41467-023-40635-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Accepted: 08/03/2023] [Indexed: 08/16/2023] Open
Abstract
The opportunistic fungal pathogen Cryptococcus neoformans causes lethal infections in immunocompromised patients. Macrophages are central to the host response to cryptococci; however, it is unclear how C. neoformans is recognised and phagocytosed by macrophages. Here we investigate the role of TLR4 in the non-opsonic phagocytosis of C. neoformans. We find that loss of TLR4 function unexpectedly increases phagocytosis of non-opsonised cryptococci by murine and human macrophages. The increased phagocytosis observed in Tlr4-/- cells was dampened by pre-treatment of macrophages with oxidised-LDL, a known ligand of scavenger receptors. The scavenger receptor, macrophage scavenger receptor 1 (MSR1) (also known as SR-A1 or CD204) was upregulated in Tlr4-/- macrophages. Genetic ablation of MSR1 resulted in a 75% decrease in phagocytosis of non-opsonised cryptococci, strongly suggesting that it is a key non-opsonic receptor for this pathogen. We go on to show that MSR1-mediated uptake likely involves the formation of a multimolecular signalling complex involving FcγR leading to SYK, PI3K, p38 and ERK1/2 activation to drive actin remodelling and phagocytosis. Altogether, our data indicate a hitherto unidentified role for TLR4/MSR1 crosstalk in the non-opsonic phagocytosis of C. neoformans.
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Affiliation(s)
- Chinaemerem U Onyishi
- Institute of Microbiology & Infection and School of Biosciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom
| | - Guillaume E Desanti
- Institute of Microbiology & Infection and School of Biosciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom
| | - Alex L Wilkinson
- Institute of Microbiology & Infection and School of Biosciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom
| | - Samuel Lara-Reyna
- Institute of Microbiology & Infection and School of Biosciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom
| | - Eva-Maria Frickel
- Institute of Microbiology & Infection and School of Biosciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom
| | - Gyorgy Fejer
- School of Biomedical Sciences, Faculty of Health, University of Plymouth, Plymouth, United Kingdom
| | - Olivier D Christophe
- Université Paris-Saclay, INSERM, Hémostase inflammation thrombose HITH U1176, 94276, Le Kremlin-Bicêtre, France
| | - Clare E Bryant
- University of Cambridge, Department of Medicine, Box 157, Level 5, Addenbrooke's Hospital, Hills Road, Cambridge, CB2 0QQ, United Kingdom
| | - Subhankar Mukhopadhyay
- Peter Gorer Department of Immunobiology, School of Immunology & Microbial Sciences, King's College London, London, SE1 9RT, United Kingdom
| | - 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, B15 2TT, United Kingdom.
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Huang J, Lei J, Ge A, Xiao W, Xin C, Song Z, Zhang J. Antifungal Effect of Vitamin D 3 against Cryptococcus neoformans Coincides with Reduced Biofilm Formation, Compromised Cell Wall Integrity, and Increased Generation of Reactive Oxygen Species. J Fungi (Basel) 2023; 9:772. [PMID: 37504760 PMCID: PMC10381739 DOI: 10.3390/jof9070772] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Revised: 07/15/2023] [Accepted: 07/20/2023] [Indexed: 07/29/2023] Open
Abstract
Cryptococcus neoformans is an invasive fungus that causes both acute and chronic infections, especially in immunocompromised patients. Owing to the increase in the prevalence of drug-resistant pathogenic fungi and the limitations of current treatment strategies, drug repositioning has become a feasible strategy to accelerate the development of new drugs. In this study, the minimum inhibitory concentration of vitamin D3 (VD3) against C. neoformans was found to be 0.4 mg/mL by broth microdilution assay. The antifungal activities of VD3 were further verified by solid dilution assays and "time-kill" curves. The results showed that VD3 reduced fungal cell adhesion and hydrophobicity and inhibited biofilm formation at various developmental stages, as confirmed by crystal violet staining and the 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide assay. Fluorescence staining of cellular components and a stress susceptibility assay indicated that VD3 compromised cell integrity. Reverse transcription quantitative PCR demonstrated that VD3 treatment upregulated the expression of fungal genes related to cell wall synthesis (i.e., CDA3, CHS3, FKS1, and AGS1). Moreover, VD3 enhanced cell membrane permeability and caused the accumulation of intracellular reactive oxygen species. Finally, VD3 significantly reduced the tissue fungal burden and prolonged the survival of Galleria mellonella larvae infected with C. neoformans. These results showed that VD3 could exert significant antifungal activities both in vitro and in vivo, demonstrating its potential application in the treatment of cryptococcal infections.
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Affiliation(s)
- Jian Huang
- Public Center of Experimental Technology, School of Basic Medical Sciences, Southwest Medical University, Luzhou 646000, China
| | - Junwen Lei
- Public Center of Experimental Technology, School of Basic Medical Sciences, Southwest Medical University, Luzhou 646000, China
| | - Anni Ge
- Public Center of Experimental Technology, School of Basic Medical Sciences, Southwest Medical University, Luzhou 646000, China
| | - Wei Xiao
- Public Center of Experimental Technology, School of Basic Medical Sciences, Southwest Medical University, Luzhou 646000, China
| | - Caiyan Xin
- Public Center of Experimental Technology, School of Basic Medical Sciences, Southwest Medical University, Luzhou 646000, China
| | - Zhangyong Song
- Public Center of Experimental Technology, School of Basic Medical Sciences, Southwest Medical University, Luzhou 646000, China
| | - Jinping Zhang
- Public Center of Experimental Technology, School of Basic Medical Sciences, Southwest Medical University, Luzhou 646000, China
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Copplestone D, Coates CJ, Lim J. Low dose γ-radiation induced effects on wax moth (Galleria mellonella) larvae. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 876:162742. [PMID: 36906041 DOI: 10.1016/j.scitotenv.2023.162742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 02/10/2023] [Accepted: 03/05/2023] [Indexed: 06/18/2023]
Abstract
Larvae of the greater wax moth Galleria mellonella are common pests of beehives and commercial apiaries, and in more applied settings, these insects act as alternative in vivo bioassays to rodents for studying microbial virulence, antibiotic development, and toxicology. In the current study, our aim was to assess the putative adverse effects of background gamma radiation levels on G. mellonella. To achieve this, we exposed larvae to low (0.014 mGy/h), medium (0.056 mGy/h), and high (1.33 mGy/h) doses of caesium-137 and measured larval pupation events, weight, faecal discharge, susceptibility to bacterial and fungal challenges, immune cell counts, activity, and viability (i.e., haemocyte encapsulation) and melanisation levels. The effects of low and medium levels of radiation were distinguishable from the highest dose rates used - the latter insects weighed the least and pupated earlier. In general, radiation exposure modulated cellular and humoral immunity over time, with larvae showing heightened encapsulation/melanisation levels at the higher dose rates but were more susceptible to bacterial (Photorhabdus luminescens) infection. There were few signs of radiation impacts after 7 days exposure, whereas marked changes were recorded between 14 and 28 days. Our data suggest that G. mellonella demonstrates plasticity at the whole organism and cellular levels when irradiated and offers insight into how such animals may cope in radiologically contaminated environments (e.g. Chornobyl Exclusion Zone).
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Affiliation(s)
- David Copplestone
- Biological and Environmental Sciences, Faculty of Natural Sciences, University of Stirling, Stirling FK9 4LA, Scotland, UK
| | - Christopher J Coates
- Department of Biosciences, Faculty of Science and Engineering, Swansea University, Swansea SA2 8PP, Wales, UK; Zoology, Ryan Institute, School of Natural Sciences, University of Galway, Galway H91 TK33, Ireland
| | - Jenson Lim
- Biological and Environmental Sciences, Faculty of Natural Sciences, University of Stirling, Stirling FK9 4LA, Scotland, UK.
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5
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COVID-19 Associated with Cryptococcosis: A New Challenge during the Pandemic. J Fungi (Basel) 2022; 8:jof8101111. [PMID: 36294675 PMCID: PMC9604822 DOI: 10.3390/jof8101111] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 10/19/2022] [Accepted: 10/19/2022] [Indexed: 11/16/2022] Open
Abstract
Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a great threat to global health. In addition to SARS-CoV-2 itself, clinicians should be alert to the possible occurrence of co-infection or secondary infection among patients with COVID-19. The possible co-pathogens include bacteria, viruses, and fungi, but COVID-19-associated cryptococcosis is rarely reported. This review provided updated and comprehensive information about this rare clinical entity of COVID-19-associated cryptococcosis. Through an updated literature search till 23 August 2022, we identified a total of 18 culture-confirmed case reports with detailed information. Half (n = 9) of them were elderly. Fifteen (83.3%) of them had severe COVID-19 and ever received systemic corticosteroid. Disseminated infection with cryptococcemia was the most common type of cryptococcosis, followed by pulmonary and meningitis. Except one case of C. laurentii, all other cases are by C. neoformans. Liposomal amphotericin B and fluconazole were the most commonly used antifungal agents. The overall mortality was 61.1% (11/18) and four of them did not receive antifungal agents before death. Improving the poor outcome requires a physician's high suspicion, early diagnosis, and prompt treatment.
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Yang C, Huang Y, Zhou Y, Zang X, Deng H, Liu Y, Shen D, Xue X. Cryptococcus escapes host immunity: What do we know? Front Cell Infect Microbiol 2022; 12:1041036. [PMID: 36310879 PMCID: PMC9606624 DOI: 10.3389/fcimb.2022.1041036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2022] [Accepted: 09/30/2022] [Indexed: 11/13/2022] Open
Abstract
Cryptococcus is an invasive fungus that seriously endangers human life and health, with a complex and well-established immune-escaping mechanism that interferes with the function of the host immune system. Cryptococcus can attenuate the host’s correct recognition of the fungal antigen and escape the immune response mediated by host phagocytes, innate lymphoid cells, T lymphocytes, B lymphocytes with antibodies, and peripheral cytokines. In addition, the capsule, melanin, dormancy, Titan cells, biofilm, and other related structures of Cryptococcus are also involved in the process of escaping the host’s immunity, as well as enhancing the ability of Cryptococcus to infect the host.
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Affiliation(s)
- Chen Yang
- Department of Laboratory Medicine, the First Medical Centre, Chinese People's Liberation Army (PLA) General Hospital, Beijing, China
| | - Yemei Huang
- Department of Respiratory and Critical Care, Beijing Shijitan Hospital, Capital Medical University, Peking University Ninth School of Clinical Medicine, Beijing, China
| | - Yangyu Zhou
- Department of Respiratory and Critical Care, Beijing Shijitan Hospital, Capital Medical University, Peking University Ninth School of Clinical Medicine, Beijing, China
| | - Xuelei Zang
- Department of Respiratory and Critical Care, Beijing Shijitan Hospital, Capital Medical University, Peking University Ninth School of Clinical Medicine, Beijing, China
| | - Hengyu Deng
- School of Clinical Medicine, Weifang Medical University, Weifang, China
| | - Yitong Liu
- Department of Respiratory and Critical Care, Beijing Shijitan Hospital, Capital Medical University, Peking University Ninth School of Clinical Medicine, Beijing, China
| | - Dingxia Shen
- Department of Laboratory Medicine, the First Medical Centre, Chinese People's Liberation Army (PLA) General Hospital, Beijing, China
- *Correspondence: Dingxia Shen, ; Xinying Xue,
| | - Xinying Xue
- Department of Respiratory and Critical Care, Beijing Shijitan Hospital, Capital Medical University, Peking University Ninth School of Clinical Medicine, Beijing, China
- School of Clinical Medicine, Weifang Medical University, Weifang, China
- *Correspondence: Dingxia Shen, ; Xinying Xue,
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7
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Denham ST, Brammer B, Chung KY, Wambaugh MA, Bednarek JM, Guo L, Moreau CT, Brown JCS. A dissemination-prone morphotype enhances extrapulmonary organ entry by Cryptococcus neoformans. Cell Host Microbe 2022; 30:1382-1400.e8. [PMID: 36099922 PMCID: PMC9588642 DOI: 10.1016/j.chom.2022.08.017] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 06/01/2022] [Accepted: 08/18/2022] [Indexed: 01/08/2023]
Abstract
Environmental pathogens move from ecological niches to mammalian hosts, requiring adaptation to dramatically different environments. Microbes that disseminate farther, including the fungal meningitis pathogen Cryptococcus neoformans, require additional adaptation to diverse tissues. We demonstrate that the formation of a small C. neoformans morphotype-called "seed" cells due to their colonizing ability-is critical for extrapulmonary organ entry. Seed cells exhibit changes in fungal cell size and surface expression that result in an enhanced macrophage update. Seed cell formation is triggered by environmental factors, including C. neoformans' environmental niche, and pigeon guano with phosphate plays a central role. Seed cells show the enhanced expression of phosphate acquisition genes, and mutants unable to acquire phosphate fail to adopt the seed cell morphotype. Additionally, phosphate can be released by tissue damage, potentially establishing a feed-forward loop of seed cell formation and dissemination. Thus, C. neoformans' size variation represent inducible morphotypes that change host interactions to facilitate microbe spread.
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Affiliation(s)
- Steven T Denham
- Division of Microbiology and Immunology, Department of Pathology, University of Utah, Salt Lake City, UT 84112, USA
| | - Brianna Brammer
- Division of Microbiology and Immunology, Department of Pathology, University of Utah, Salt Lake City, UT 84112, USA
| | - Krystal Y Chung
- Division of Microbiology and Immunology, Department of Pathology, University of Utah, Salt Lake City, UT 84112, USA
| | - Morgan A Wambaugh
- Division of Microbiology and Immunology, Department of Pathology, University of Utah, Salt Lake City, UT 84112, USA
| | - Joseph M Bednarek
- Division of Microbiology and Immunology, Department of Pathology, University of Utah, Salt Lake City, UT 84112, USA
| | - Li Guo
- Molecular Medicine Program, University of Utah, Salt Lake City, UT 84112, USA
| | - Christian T Moreau
- Division of Microbiology and Immunology, Department of Pathology, University of Utah, Salt Lake City, UT 84112, USA
| | - Jessica C S Brown
- Division of Microbiology and Immunology, Department of Pathology, University of Utah, Salt Lake City, UT 84112, USA.
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Oliveira-Brito PKM, de Campos GY, Guimarães JG, Serafim da Costa L, Silva de Moura E, Lazo-Chica JE, Roque-Barreira MC, da Silva TA. Adjuvant Curdlan Contributes to Immunization against Cryptococcus gattii Infection in a Mouse Strain-Specific Manner. Vaccines (Basel) 2022; 10:vaccines10040620. [PMID: 35455369 PMCID: PMC9030172 DOI: 10.3390/vaccines10040620] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 04/05/2022] [Accepted: 04/07/2022] [Indexed: 02/06/2023] Open
Abstract
The low efficacy and side effects associated with antifungal agents have highlighted the importance of developing immunotherapeutic approaches to treat Cryptococcus gattii infection. We developed an immunization strategy that uses selective Dectin-1 agonist as an adjuvant. BALB/c or C57BL/6 mice received curdlan or β-glucan peptide (BGP) before immunization with heat-killed C. gattii, and the mice were infected with viable C. gattii on day 14 post immunization and euthanized 14 days after infection. Adjuvant curdlan restored pulmonary tumor necrosis factor- α (TNF-α) levels, as induced by immunization with heat-killed C. gattii. The average area and relative frequency of C. gattii titan cells in the lungs of curdlan-treated BALB/c mice were reduced. However, this did not reduce the pulmonary fungal burden or decrease the i0,nflammatory infiltrate in the pulmonary parenchyma of BALB/c mice. Conversely, adjuvant curdlan induced high levels of interferon-γ (IFN-γ) and interleukin (IL)-10 and decreased the C. gattii burden in the lungs of C57BL/6 mice, which was not replicated in β-glucan peptide-treated mice. The adjuvant curdlan favors the control of C. gattii infection depending on the immune response profile of the mouse strain. This study will have implications for developing new immunotherapeutic approaches to treat C. gattii infection.
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Affiliation(s)
- Patrícia Kellen Martins Oliveira-Brito
- Department of Cell and Molecular Biology and Pathogenic Bioagents, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto 14049-900, SP, Brazil; (P.K.M.O.-B.); (G.Y.d.C.); (J.G.G.); (E.S.d.M.); (M.C.R.-B.)
| | - Gabriela Yamazaki de Campos
- Department of Cell and Molecular Biology and Pathogenic Bioagents, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto 14049-900, SP, Brazil; (P.K.M.O.-B.); (G.Y.d.C.); (J.G.G.); (E.S.d.M.); (M.C.R.-B.)
| | - Júlia Garcia Guimarães
- Department of Cell and Molecular Biology and Pathogenic Bioagents, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto 14049-900, SP, Brazil; (P.K.M.O.-B.); (G.Y.d.C.); (J.G.G.); (E.S.d.M.); (M.C.R.-B.)
| | - Letícia Serafim da Costa
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo 14049-900, SP, Brazil;
| | - Edanielle Silva de Moura
- Department of Cell and Molecular Biology and Pathogenic Bioagents, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto 14049-900, SP, Brazil; (P.K.M.O.-B.); (G.Y.d.C.); (J.G.G.); (E.S.d.M.); (M.C.R.-B.)
| | - Javier Emílio Lazo-Chica
- Institute of Natural and Biological Sciences, Federal University of Triângulo Mineiro, Uberaba 38025-189, MG, Brazil;
| | - Maria Cristina Roque-Barreira
- Department of Cell and Molecular Biology and Pathogenic Bioagents, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto 14049-900, SP, Brazil; (P.K.M.O.-B.); (G.Y.d.C.); (J.G.G.); (E.S.d.M.); (M.C.R.-B.)
| | - Thiago Aparecido da Silva
- Department of Cell and Molecular Biology and Pathogenic Bioagents, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto 14049-900, SP, Brazil; (P.K.M.O.-B.); (G.Y.d.C.); (J.G.G.); (E.S.d.M.); (M.C.R.-B.)
- Thiago Aparecido da Silva, Departamento de Biologia Celular e Molecular e Bioagentes Patogênicos, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Avenida Bandeirantes 3900, Ribeirão Preto 14049-900, SP, Brazil
- Correspondence: or ; Tel.: +55-16-3315-3049
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9
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Onyishi CU, May RC. Human immune polymorphisms associated with the risk of cryptococcal disease. Immunology 2021; 165:143-157. [PMID: 34716931 PMCID: PMC9426616 DOI: 10.1111/imm.13425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 10/07/2021] [Accepted: 10/16/2021] [Indexed: 11/29/2022] Open
Abstract
Cryptococcus neoformans is an opportunistic fungal pathogen that can cause lethal cryptococcal meningitis in immunocompromised individuals such as those with HIV/AIDS. In addition, cryptococcal infections occasionally arise in immunocompetent individuals or those with previously undiagnosed immunodeficiencies. The course of cryptococcosis is highly variable in both patient groups, and there is rapidly growing evidence that genetic polymorphisms may have a significant impact on the trajectory of disease. Here, we review what is currently known about the nature of these polymorphisms and their impact on host response to C. neoformans infection. Thus far, polymorphisms in Fc gamma receptors, mannose‐binding lectin, Dectin‐2, Toll‐like receptors and macrophage colony‐stimulating factor have been associated with susceptibility to cryptococcal disease. Notably, however, in some cases the impact of these polymorphisms depends on the genetic background of the population; for example, the FCGR3A 158 F/V polymorphism was associated with an increased risk of cryptococcal disease in both HIV‐positive and HIV‐negative white populations, but not in Han Chinese patients. In most cases, the precise mechanism by which the identified polymorphisms influence disease progression remains unclear, although impaired fungal recognition and phagocytosis by innate immune cells appears to play a major role. Finally, we highlight outstanding questions in the field and emphasize the need for future research to include more diverse populations in their genetic association studies.
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Affiliation(s)
- Chinaemerem U Onyishi
- Institute of Microbiology & Infection, School of Biosciences, University of Birmingham, Birmingham, UK
| | - Robin C May
- Institute of Microbiology & Infection, School of Biosciences, University of Birmingham, Birmingham, UK
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10
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Huang XW, Xu MN, Zheng HX, Wang ML, Li L, Zeng K, Li DD. Pre-exposure to Candida glabrata protects Galleria mellonella against subsequent lethal fungal infections. Virulence 2021; 11:1674-1684. [PMID: 33200667 PMCID: PMC7714416 DOI: 10.1080/21505594.2020.1848107] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Commensal fungi are an important part of human microbial community, among which Candida albicans and Candida glabrata are two common opportunistic pathogens. Unlike the high pathogenicity of C. albicans, C. glabrata is reported to show low pathogenicity to the host. Here, by using a Galleria mellonella infection model, we were able to confirm the much lower virulence of C. glabrata than C. albicans. Interestingly, pre-exposure to live C. glabrata (LCG) protects the larvae against subsequent various lethal fungal infections, including C. albicans, Candida tropicalis, and Cryptococcus neoformans. Inconsistently, heat-inactivated C. glabrata (HICG) pre-exposure can only protect against C. albicans or C. tropicalis re-infection, but not C. neoformans. Mechanistically, LCG or HICG pre-exposure enhanced the fungicidal activity of hemocytes against C. albicans or C. tropicalis. Meanwhile, LCG pre-exposure enhanced the humoral immunity by modulating the expression of fungal defending proteins in the cell-free hemolymph, which may contribute to the protection against C. neoformans. Together, this study suggests the important role of C. glabrata in enhancing host immunity, and demonstrates the great potential of G. mellonella model in studying the innate immune responses against infections.
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Affiliation(s)
- Xiao-Wen Huang
- Department of Dermatology, Nanfang Hospital, Southern Medical University , Guangzhou, China
| | - Mei-Nian Xu
- Department of Dermatology, Nanfang Hospital, Southern Medical University , Guangzhou, China
| | - Huan-Xin Zheng
- Department of Dermatology, Nanfang Hospital, Southern Medical University , Guangzhou, China
| | - Meng-Lei Wang
- Department of Dermatology, Nanfang Hospital, Southern Medical University , Guangzhou, China
| | - Li Li
- Department of Dermatology, Nanfang Hospital, Southern Medical University , Guangzhou, China
| | - Kang Zeng
- Department of Dermatology, Nanfang Hospital, Southern Medical University , Guangzhou, China
| | - De-Dong Li
- Division of Rheumatology and Clinical Immunology, Department of Medicine, University of Pittsburgh , Pittsburgh, PA, USA.,Central Laboratory, Shanghai Skin Disease Hospital, Tongji University School of Medicine , Shanghai, China
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11
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Emery H, Traves W, Rowley AF, Coates CJ. The diarrhetic shellfish-poisoning toxin, okadaic acid, provokes gastropathy, dysbiosis and susceptibility to bacterial infection in a non-rodent bioassay, Galleria mellonella. Arch Toxicol 2021; 95:3361-3376. [PMID: 34374792 PMCID: PMC8448676 DOI: 10.1007/s00204-021-03132-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Accepted: 08/04/2021] [Indexed: 11/30/2022]
Abstract
Diarrhetic shellfish-poisoning (DSP) toxins such as okadaic acid and dinophysistoxins harm the human gastrointestinal tract, and therefore, their levels are regulated to an upper limit of 160 μg per kg tissue to protect consumers. Rodents are used routinely for risk assessment and studies concerning mechanisms of toxicity, but there is a general move toward reducing and replacing vertebrates for these bioassays. We have adopted insect larvae of the wax moth Galleria mellonella as a surrogate toxicology model. We treated larvae with environmentally relevant doses of okadaic acid (80–400 μg/kg) via intrahaemocoelic injection or gavage to determine marine toxin-related health decline: (1) whether pre-exposure to a sub-lethal dose of toxin (80 μg/kg) enhances susceptibility to bacterial infection, or (2) alters tissue pathology and bacterial community (microbiome) composition of the midgut. A sub-lethal dose of okadaic acid (80 μg/kg) followed 24 h later by bacterial inoculation (2 × 105Escherichia coli) reduced larval survival levels to 47%, when compared to toxin (90%) or microbial challenge (73%) alone. Histological analysis of the midgut depicted varying levels of tissue disruption, including nuclear aberrations associated with cell death (karyorrhexis, pyknosis), loss of organ architecture, and gross epithelial displacement into the lumen. Moreover, okadaic acid presence in the midgut coincided with a shift in the resident bacterial population over time in that substantial reductions in diversity (Shannon) and richness (Chao-1) indices were observed at 240 μg toxin per kg. Okadaic acid-induced deterioration of the insect alimentary canal resembles those changes reported for rodent bioassays.
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Affiliation(s)
- Helena Emery
- Department of Biosciences, Faculty of Science and Engineering, Swansea University, Swansea, Wales, SA2 8PP, UK
| | - William Traves
- Department of Biosciences, Faculty of Science and Engineering, Swansea University, Swansea, Wales, SA2 8PP, UK
| | - Andrew F Rowley
- Department of Biosciences, Faculty of Science and Engineering, Swansea University, Swansea, Wales, SA2 8PP, UK
| | - Christopher J Coates
- Department of Biosciences, Faculty of Science and Engineering, Swansea University, Swansea, Wales, SA2 8PP, UK.
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12
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Emery H, Butt TM, Coates CJ. Nutraceutical intervention protects against bacterial and chemical-induced gastrotoxicity in a non-mammalian model, Galleria mellonella. Food Chem Toxicol 2021; 154:112354. [PMID: 34146620 DOI: 10.1016/j.fct.2021.112354] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 05/26/2021] [Accepted: 06/11/2021] [Indexed: 12/18/2022]
Abstract
Preparations of the fungus Cordyceps sinensis and bovine colostrum are considered nutraceuticals due to their anti-inflammatory, repair and gut alimentation properties in mammalian models. To reduce the reliance on rodents in routine experimentation, we gauged the capacity of nutraceuticals to alleviate gastric damage in an insect surrogate, Galleria mellonella. Larvae were reared on standard or supplemented diets - 10% (w/w) colostrum, 10% (w/w) C. sinensis, or 5% + 5% each - prior to receiving an oral dose of the NSAID indomethacin (30 mg/kg) or challenged with the bacterial pathogen Campylobacter jejuni (1-3 x106) via two inoculation routes. Insects reared on a cordyceps-supplemented diet proved most resistant to indomethacin-induced gut leakiness, and displayed stable health indices after C. jejuni challenge (~77% survival). Insects reared on a colostrum-supplemented diet also showed recalcitrance in the gut, but were more sensitive to C. jejuni when injected directly into the body cavity (50% survival). The nutraceutical blend yielded improved health outcomes when compared to the standard diet, but was not as effective as either nutraceutical alone. Our findings represent clear evidence that insects were more resistant to known chemical and microbial agitators when reared on nutraceutical-supplemented diets - toxicological endpoints that are shared with vertebrate studies.
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Affiliation(s)
- Helena Emery
- Department of Biosciences, Faculty of Science and Engineering, Swansea University, Swansea, SA2 8PP, Wales, UK
| | - Tariq M Butt
- Department of Biosciences, Faculty of Science and Engineering, Swansea University, Swansea, SA2 8PP, Wales, UK
| | - Christopher J Coates
- Department of Biosciences, Faculty of Science and Engineering, Swansea University, Swansea, SA2 8PP, Wales, UK.
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13
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Replicative Aging Remodels the Cell Wall and Is Associated with Increased Intracellular Trafficking in Human Pathogenic Yeasts. mBio 2021; 13:e0019022. [PMID: 35164553 PMCID: PMC8844920 DOI: 10.1128/mbio.00190-22] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Replicative aging is an underexplored field of research in medical mycology. Cryptococcus neoformans (Cn) and Candida glabrata (Cg) are dreaded fungal pathogens that cause fatal invasive infections. The fungal cell wall is essential for yeast viability and pathogenesis. In this study, we provide data characterizing age-associated modifications to the cell wall of Cn and Cg. Here, we report that old yeast cells upregulate genes of cell wall biosynthesis, leading to cell wall reorganization and increased levels of all major components, including glucan, chitin, and its derivatives, as well as mannan. This results in a significant thickening of the cell wall in aged cells. Old-generation yeast cells exhibited drastic ultrastructural changes, including the presence of abundant vesicle-like particles in the cytoplasm, and enlarged vacuoles with altered pH homeostasis. Our findings suggest that the cell wall modifications could be enabled by augmented intracellular trafficking. This work furthers our understanding of the cell phenotype that emerges during aging. It highlights differences in these two fungal pathogens and elucidates mechanisms that explain the enhanced resistance of old cells to antifungals and phagocytic attacks. IMPORTANCE Cryptococcus neoformans and Candida glabrata are two opportunistic human fungal pathogens that cause life-threatening diseases. During infection, both microorganisms have the ability to persist for long periods, and treatment failure can occur even if standard testing identifies the yeasts to be sensitive to antifungals. Replicative life span is a trait that is measured by the number of divisions a cell undergoes before death. Aging in fungi is associated with enhanced tolerance to antifungals and resistance to phagocytosis, and characterization of old cells may help identify novel antifungal targets. The cell wall remains an attractive target for new therapies because it is essential for fungi and is not present in humans. This study shows that the organization of the fungal cell wall changes remarkably during aging and becomes thicker and is associated with increased intracellular trafficking as well as the alteration of vacuole morphology and pH homeostasis.
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14
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Last A, Maurer M, Mosig AS, Gresnigt MS, Hube B. In vitro infection models to study fungal-host interactions. FEMS Microbiol Rev 2021; 45:6125970. [PMID: 33524102 PMCID: PMC8498566 DOI: 10.1093/femsre/fuab005] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Accepted: 01/14/2021] [Indexed: 12/14/2022] Open
Abstract
Fungal infections (mycoses) affect over a billion people per year. Approximately, two million of these infections are life-threatening, especially for patients with a compromised immune system. Fungi of the genera Aspergillus, Candida, Histoplasma and Cryptococcus are opportunistic pathogens that contribute to a substantial number of mycoses. To optimize the diagnosis and treatment of mycoses, we need to understand the complex fungal–host interplay during pathogenesis, the fungal attributes causing virulence and how the host resists infection via immunological defenses. In vitro models can be used to mimic fungal infections of various tissues and organs and the corresponding immune responses at near-physiological conditions. Furthermore, models can include fungal interactions with the host–microbiota to mimic the in vivo situation on skin and mucosal surfaces. This article reviews currently used in vitro models of fungal infections ranging from cell monolayers to microfluidic 3D organ-on-chip (OOC) platforms. We also discuss how OOC models can expand the toolbox for investigating interactions of fungi and their human hosts in the future.
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Affiliation(s)
- Antonia Last
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology - Hans-Knoell-Institute, Jena, Germany
| | - Michelle Maurer
- Center for Sepsis Control and Care (CSCC), University Hospital Jena, Jena, Germany.,Institute of Biochemistry II, Jena University Hospital, Jena, Germany
| | - Alexander S Mosig
- Center for Sepsis Control and Care (CSCC), University Hospital Jena, Jena, Germany.,Institute of Biochemistry II, Jena University Hospital, Jena, Germany
| | - Mark S Gresnigt
- Junior Research Group Adaptive Pathogenicity Strategies, Leibniz Institute for Natural Product Research and Infection Biology - Hans-Knoell-Institute, Jena, Germany
| | - Bernhard Hube
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology - Hans-Knoell-Institute, Jena, Germany.,Institute of Microbiology, Friedrich Schiller University, Jena, Germany
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15
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Ciociola T, Zanello PP, D’Adda T, Galati S, Conti S, Magliani W, Giovati L. A Peptide Found in Human Serum, Derived from the C-Terminus of Albumin, Shows Antifungal Activity In Vitro and In Vivo. Microorganisms 2020; 8:E1627. [PMID: 33096923 PMCID: PMC7588913 DOI: 10.3390/microorganisms8101627] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Revised: 10/16/2020] [Accepted: 10/17/2020] [Indexed: 01/19/2023] Open
Abstract
The growing problem of antimicrobial resistance highlights the need for alternative strategies to combat infections. From this perspective, there is a considerable interest in natural molecules obtained from different sources, which are shown to be active against microorganisms, either alone or in association with conventional drugs. In this paper, peptides with the same sequence of fragments, found in human serum, derived from physiological proteins, were evaluated for their antifungal activity. A 13-residue peptide, representing the 597-609 fragment within the albumin C-terminus, was proved to exert a fungicidal activity in vitro against pathogenic yeasts and a therapeutic effect in vivo in the experimental model of candidal infection in Galleria mellonella. Studies by confocal microscopy and transmission and scanning electron microscopy demonstrated that the peptide penetrates and accumulates in Candida albicans cells, causing gross morphological alterations in cellular structure. These findings add albumin to the group of proteins, which already includes hemoglobin and antibodies, that could give rise to cryptic antimicrobial fragments, and could suggest their role in anti-infective homeostasis. The study of bioactive fragments from serum proteins could open interesting perspectives for the development of new antimicrobial molecules derived by natural sources.
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Affiliation(s)
- Tecla Ciociola
- Department of Medicine and Surgery, University of Parma, 43126 Parma, Italy; (T.C.); (P.P.Z.); (T.D.); (W.M.); (L.G.)
| | - Pier Paolo Zanello
- Department of Medicine and Surgery, University of Parma, 43126 Parma, Italy; (T.C.); (P.P.Z.); (T.D.); (W.M.); (L.G.)
| | - Tiziana D’Adda
- Department of Medicine and Surgery, University of Parma, 43126 Parma, Italy; (T.C.); (P.P.Z.); (T.D.); (W.M.); (L.G.)
| | - Serena Galati
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, 43124 Parma, Italy;
| | - Stefania Conti
- Department of Medicine and Surgery, University of Parma, 43126 Parma, Italy; (T.C.); (P.P.Z.); (T.D.); (W.M.); (L.G.)
| | - Walter Magliani
- Department of Medicine and Surgery, University of Parma, 43126 Parma, Italy; (T.C.); (P.P.Z.); (T.D.); (W.M.); (L.G.)
| | - Laura Giovati
- Department of Medicine and Surgery, University of Parma, 43126 Parma, Italy; (T.C.); (P.P.Z.); (T.D.); (W.M.); (L.G.)
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16
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Grizanova EV, Coates CJ, Dubovskiy IM, Butt TM. Metarhizium brunneum infection dynamics differ at the cuticle interface of susceptible and tolerant morphs of Galleria mellonella. Virulence 2020; 10:999-1012. [PMID: 31724467 PMCID: PMC8647853 DOI: 10.1080/21505594.2019.1693230] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
In order for entomopathogenic fungi to colonize an insect host, they must first attach to, and penetrate, the cuticle layers of the integument. Herein, we explored the interactions between the fungal pathogen Metarhizium brunneum ARSEF 4556 and two immunologically distinct morphs, melanic (M) and non-melanic (NM), of the greater wax moth Galleria mellonella. We first interrogated the cuticular compositions of both insect morphs to reveal substantial differences in their physiochemical properties. Enhanced melanin accumulation, fewer hydrocarbons, and higher L-dihydroxyphenylalanine (DOPA) decarboxylase activity were evident in the cuticle of the M larvae. This “hostile” terrain proved challenging for M. brunneum – reflected in poor conidial attachment and germination, and elevated expression of stress-associated genes (e.g., Hsp30, Hsp70). Lack of adherence to the cuticle impacted negatively on the speed of kill and overall host mortality; a dose of 107 conidia killed ~30% of M larvae over a 12-day period, whereas a 100-fold lower dose (105 conidia) achieved a similar result for NM larvae. Candidate gene expression patterns between the insect morphs indicated that M larvae are primed to “switch-on” immunity-associated genes (e.g., phenoloxidase) within 6–12 h of conidia exposure and can sustain a “defense” response. Critically, M. brunneum responds to the distinct physiochemical cues of both hosts and adjusts the expression of pathogenicity-related genes accordingly (e.g., Pr2, Mad1, Mad2). We reveal previously uncharacterized mechanisms of attack and defence in fungal-insect antibiosis.
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Affiliation(s)
- Ekaterina V Grizanova
- Laboratory of Biological Plant Protection and Biotechnology, Novosibirsk State Agrarian University, Novosibirsk, Russia
| | | | - Ivan M Dubovskiy
- Laboratory of Biological Plant Protection and Biotechnology, Novosibirsk State Agrarian University, Novosibirsk, Russia.,Siberian Federal Scientific Centre of Agro-BioTechnologies, Russian Academy of Sciences, Krasnoobsk, Russia
| | - Tariq M Butt
- Department of Biosciences, College of Science, Swansea University, Swansea, UK
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17
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Garcia AWA, Kinskovski UP, Diehl C, Reuwsaat JCV, Motta de Souza H, Pinto HB, Trentin DDS, de Oliveira HC, Rodrigues ML, Becker EM, Kmetzsch L, Vainstein MH, Staats CC. Participation of Zip3, a ZIP domain-containing protein, in stress response and virulence in Cryptococcus gattii. Fungal Genet Biol 2020; 144:103438. [PMID: 32738289 DOI: 10.1016/j.fgb.2020.103438] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 07/21/2020] [Accepted: 07/22/2020] [Indexed: 12/16/2022]
Abstract
Cryptococcus gattii is an etiologic agent of cryptococcosis, a potentially fatal disease that affects humans and animals. The successful infection of mammalian hosts by cryptococcal cells relies on their ability to infect and survive in macrophages. Such phagocytic cells present a hostile environment to intracellular pathogens via the production of reactive nitrogen and oxygen species, as well as low pH and reduced nutrient bioavailability. To overcome the low-metal environment found during infection, fungal pathogens express high-affinity transporters, including members of the ZIP family. Previously, we determined that functional zinc uptake driven by Zip1 and Zip2 is necessary for full C.gattiivirulence. Here, we characterized the ZIP3 gene of C. gattii, an ortholog of the Saccharomyces cerevisiae ATX2, which codes a manganese transporter localized to the membrane of the Golgi apparatus. Cryptococcal cells lacking Zip3 were tolerant to toxic concentrations of manganese and had imbalanced expression of intracellular metal transporters, such as the vacuolar Pmc1 and Vcx1, as well as the Golgi Pmr1. Moreover, null mutants of the ZIP3 gene displayed higher sensitivity to reactive oxygen species (ROS) and substantial alteration in the expression of ROS-detoxifying enzyme-coding genes. In line with these phenotypes, cryptococcal cells displayed decreased virulence in a non-vertebrate model of cryptococcosis. Furthermore, we found that the ZIP3 null mutant strain displayed decreased melanization and secretion of the major capsular component glucuronoxylomannan, as well as an altered extracellular vesicle dimensions profile. Collectively, our data suggest that Zip3 activity impacts the physiology, and consequently, several virulence traits of C. gattii.
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Affiliation(s)
| | - Uriel Perin Kinskovski
- Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Camila Diehl
- Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | | | - Heryk Motta de Souza
- Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Helber Barboza Pinto
- Departamento de Ciências Básicas da Saúde, Programa de Pós-Graduação em Biociências, Universidade Federal de Ciências da Saúde de Porto Alegre
| | - Danielle da Silva Trentin
- Departamento de Ciências Básicas da Saúde, Programa de Pós-Graduação em Biociências, Universidade Federal de Ciências da Saúde de Porto Alegre
| | | | - Marcio L Rodrigues
- Instituto Carlos Chagas, Fundação Oswaldo Cruz (Fiocruz), Curitiba, Brazil; Instituto de Microbiologia da Universidade Federal do Rio de Janeiro, Brazil
| | - Emilene Mendes Becker
- Instituto de Química, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Livia Kmetzsch
- Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil; Departamento de Biologia Molecular e Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Marilene Henning Vainstein
- Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil; Departamento de Biologia Molecular e Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Charley Christian Staats
- Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil; Departamento de Biologia Molecular e Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
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18
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C-Type Lectin Receptors in Antifungal Immunity. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1204:1-30. [PMID: 32152941 DOI: 10.1007/978-981-15-1580-4_1] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Most fungal species are harmless to humans and some exist as commensals on mucocutaneous surfaces. Yet many fungi are opportunistic pathogens, causing life-threatening invasive infections when the immune system becomes compromised. The fungal cell wall contains conserved pathogen-associated molecular patterns (PAMPs), which allow the immune system to distinguish between self (endogenous molecular patterns) and foreign material. Sensing of invasive microbial pathogens is achieved through recognition of PAMPs by pattern recognition receptors (PRRs). One of the predominant fungal-sensing PRRs is the C-type lectin receptor (CLR) family. These receptors bind to structures present on the fungal cell wall, eliciting various innate immune responses as well as shaping adaptive immunity. In this chapter, we specifically focus on the four major human fungal pathogens, Candida albicans, Aspergillus fumigatus, Cryptococcus neoformans and Pneumocystis jirovecii, reviewing our current understanding of the CLRs that are involved in their recognition and protection of the host.
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19
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Abstract
The respiratory tract is tasked with responding to a constant and vast influx of foreign agents. It acts as an important first line of defense in the innate immune system and as such plays a crucial role in preventing the entry of invading pathogens. While physical barriers like the mucociliary escalator exert their effects through the clearance of these pathogens, diverse and dynamic cellular mechanisms exist for the activation of the innate immune response through the recognition of pathogen-associated molecular patterns (PAMPs). These PAMPs are recognized by pattern recognition receptors (PRRs) that are expressed on a number of myeloid cells such as dendritic cells, macrophages, and neutrophils found in the respiratory tract. C-type lectin receptors (CLRs) are PRRs that play a pivotal role in the innate immune response and its regulation to a variety of respiratory pathogens such as viruses, bacteria, and fungi. This chapter will describe the function of both activating and inhibiting myeloid CLRs in the recognition of a number of important respiratory pathogens as well as the signaling events initiated by these receptors.
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20
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Höft MA, Hoving JC, Brown GD. Signaling C-Type Lectin Receptors in Antifungal Immunity. Curr Top Microbiol Immunol 2020; 429:63-101. [PMID: 32936383 DOI: 10.1007/82_2020_224] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
We are all exposed to fungal organisms daily, and although many of these organisms are not harmful, billions of people a year contract a fungal infection. Most of these infections are not fatal and can be cleared by the host immune response. However, due to an increase in high-risk populations, the global fungal burden has increased, with more than 1.5 million deaths per year caused by invasive fungal infections. The fungal cell wall is an important surface for interacting with the host immune system as it contains pathogen-associated molecular patterns (PAMPs) which are detected as being foreign by the host pattern recognition receptors (PRRs). C-type lectin receptors are a group of PRRs that play a central role in the protection against invasive fungal infections. Following the recognition of fungal PAMPs, CLRs trigger various innate and adaptive immune responses. In this chapter, we specifically focus on C-type lectin receptors capable of activating downstream signaling pathways, resulting in protective antifungal immune responses. The current roles that these signaling CLRs play in protection against four of the most prevalent fungal infections affecting humans are reviewed. These include Candida albicans, Aspergillus fumigatus, Cryptococcus neoformans and Pneumocystis jirovecii.
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Affiliation(s)
- Maxine A Höft
- AFGrica Medical Mycology Research Unit, Institute of Infectious Disease and Molecular Medicine (IDM) at the University of Cape Town, Werner & Beit South Building, Anzio Road, Observatory, 7925, Cape Town, South Africa
| | - J Claire Hoving
- AFGrica Medical Mycology Research Unit, Institute of Infectious Disease and Molecular Medicine (IDM) at the University of Cape Town, Werner & Beit South Building, Anzio Road, Observatory, 7925, Cape Town, South Africa
| | - Gordon D Brown
- Medical Research Council Centre for Medical Mycology at the University of Exeter, Geoffrey Pope Building, Stocker Road, EX4 4QD, Exeter, UK.
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21
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Hatinguais R, Willment JA, Brown GD. PAMPs of the Fungal Cell Wall and Mammalian PRRs. Curr Top Microbiol Immunol 2020; 425:187-223. [PMID: 32180018 DOI: 10.1007/82_2020_201] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Fungi are opportunistic pathogens that infect immunocompromised patients and are responsible for an estimated 1.5 million deaths every year. The antifungal innate immune response is mediated through the recognition of pathogen-associated molecular patterns (PAMPs) by the host's pattern recognition receptors (PRRs). PRRs are immune receptors that ensure the internalisation and the killing of fungal pathogens. They also mount the inflammatory response, which contributes to initiate and polarise the adaptive response, controlled by lymphocytes. Both the innate and adaptive immune responses are required to control fungal infections. The immune recognition of fungal pathogen primarily occurs at the interface between the membrane of innate immune cells and the fungal cell wall, which contains a number of PAMPs. This chapter will focus on describing the main mammalian PRRs that have been shown to bind to PAMPs from the fungal cell wall of the four main fungal pathogens: Candida albicans, Aspergillus fumigatus, Cryptococcus neoformans and Pneumocystis jirovecii. We will describe these receptors, their functions and ligands to provide the reader with an overview of how the immune system recognises fungal pathogens and responds to them.
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Affiliation(s)
- Remi Hatinguais
- MRC Centre for Medical Mycology at University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter, UK
| | - Janet A Willment
- MRC Centre for Medical Mycology at University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter, UK
| | - Gordon D Brown
- MRC Centre for Medical Mycology at University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter, UK.
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22
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Lopes JP, Stylianou M, Backman E, Holmberg S, Ekoff M, Nilsson G, Urban CF. Cryptococcus neoformans Induces MCP-1 Release and Delays the Death of Human Mast Cells. Front Cell Infect Microbiol 2019; 9:289. [PMID: 31456952 PMCID: PMC6700240 DOI: 10.3389/fcimb.2019.00289] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Accepted: 07/26/2019] [Indexed: 01/09/2023] Open
Abstract
Cryptococcosis, caused by the basidiomycete Cryptococcus neoformans, is a life-threatening disease affecting approximately one million people per year worldwide. Infection can occur when C. neoformans cells are inhaled by immunocompromised people. In order to establish infection, the yeast must bypass recognition and clearance by immune cells guarding the tissue. Using in vitro infections, we characterized the role of mast cells (MCs) in cryptococcosis. We found that MCs recognize C. neoformans and release inflammatory mediators such as tryptase and cytokines. From the latter group MCs released mainly CCL-2/MCP-1, a strong chemoattractant for monocytic cells. We demonstrated that supernatants of infected MCs recruit monocytes but not neutrophils. During infection with C. neoformans, MCs have a limited ability to kill the yeast depending on the serotype. C. neoformans, in turn, modulates the lifespan of MCs both, by presence of its polysaccharide capsule and by secreting soluble modulators. Taken together, MCs might have important contributions to fungal clearance during early stages of cryptocococis where these cells regulate recruitment of monocytes to mucosal tissues.
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Affiliation(s)
- José Pedro Lopes
- Department of Clinical Microbiology, Umeå University, Umeå, Sweden.,Umeå Centre for Microbial Research, Umeå University, Umeå, Sweden.,Laboratory for Molecular Infection Medicine Sweden, Umeå University, Umeå, Sweden
| | - Marios Stylianou
- Department of Clinical Microbiology, Umeå University, Umeå, Sweden.,Umeå Centre for Microbial Research, Umeå University, Umeå, Sweden.,Laboratory for Molecular Infection Medicine Sweden, Umeå University, Umeå, Sweden
| | - Emelie Backman
- Department of Clinical Microbiology, Umeå University, Umeå, Sweden.,Umeå Centre for Microbial Research, Umeå University, Umeå, Sweden.,Laboratory for Molecular Infection Medicine Sweden, Umeå University, Umeå, Sweden
| | - Sandra Holmberg
- Department of Clinical Microbiology, Umeå University, Umeå, Sweden.,Umeå Centre for Microbial Research, Umeå University, Umeå, Sweden.,Laboratory for Molecular Infection Medicine Sweden, Umeå University, Umeå, Sweden
| | - Maria Ekoff
- Immunology and Allergy Division, Department of Medicine Solna, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Gunnar Nilsson
- Immunology and Allergy Division, Department of Medicine Solna, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Constantin F Urban
- Department of Clinical Microbiology, Umeå University, Umeå, Sweden.,Umeå Centre for Microbial Research, Umeå University, Umeå, Sweden.,Laboratory for Molecular Infection Medicine Sweden, Umeå University, Umeå, Sweden
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Ueno K, Otani Y, Yanagihara N, Nakamura T, Shimizu K, Yamagoe S, Miyazaki Y. Cryptococcus gattii alters immunostimulatory potential in response to the environment. PLoS One 2019; 14:e0220989. [PMID: 31398236 PMCID: PMC6688814 DOI: 10.1371/journal.pone.0220989] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Accepted: 07/28/2019] [Indexed: 12/13/2022] Open
Abstract
Cryptococcus gattii is a capsular fungal pathogen, which causes life-threatening cryptococcosis in immunocompetent individuals. This emerging pathogen is less likely to be recognized by innate immunity compared to traditional Cryptococcus neoformans strains. Previous studies indicate that C-type lectin receptors (CLRs), including dectin-1 and dectin-2, play a role in recognizing cryptococcal cells; however, it remains to be elucidated whether the receptors physically associate with C. gattii yeast cell surfaces. Based on the previous findings, we hypothesized that culture conditions influence the expression or exposure of CLR ligands on C. gattii. Therefore, in the present study, we first investigated the culture conditions that induce exposure of CLR ligands on C. gattii yeast cells via the binding assay using recombinant fusion proteins of mouse CLR and IgG Fc, Fc dectin-1 and Fc dectin-2. Common fungal culture media, such as yeast extract–peptone–dextrose (YPD) broth, Sabouraud broth, and potato dextrose agar, did not induce the exposure of dectin-1 ligands, including β-1,3-glucan, on both capsular and acapsular C. gattii strains, in contrast to Fc dectin-1 and Fc dectin-2 bound to C. gattii cells growing in the conventional synthetic dextrose (SD) medium [may also be referred to as a yeast nitrogen base with glucose medium]. The medium also induced the exposure of dectin-1 ligands on C. neoformans, whereas all tested media induced dectin-1 and dectin-2 ligands in a control fungus Candida albicans. Notably, C. gattii did not expose dectin-1 ligands in SD medium supplemented with yeast extract or neutral buffer. In addition, compared to YPD medium-induced C. gattii, SD medium-induced C. gattii more efficiently induced the phosphorylation of Syk, Akt, and Erk1/2 in murine dendritic cells (DCs). Afterwards, the cells were considerably engulfed by DCs and remarkably induced DCs to secrete the inflammatory cytokines. Overall, the findings suggest that C. gattii alters its immunostimulatory potential in response to the environment.
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Affiliation(s)
- Keigo Ueno
- Department of Chemotherapy and Mycoses, National Institute of Infectious Diseases, Toyama, Shinjuku-ku, Tokyo, Japan
- * E-mail:
| | - Yoshiko Otani
- Department of Chemotherapy and Mycoses, National Institute of Infectious Diseases, Toyama, Shinjuku-ku, Tokyo, Japan
- Department of Biological Science and Technology, Faculty of Industrial Science and Technology, Tokyo University of Science, Niijuku, Katsushika-ku, Tokyo, Japan
| | - Nao Yanagihara
- Department of Chemotherapy and Mycoses, National Institute of Infectious Diseases, Toyama, Shinjuku-ku, Tokyo, Japan
- Department of Biological Science and Technology, Faculty of Industrial Science and Technology, Tokyo University of Science, Niijuku, Katsushika-ku, Tokyo, Japan
| | - Takumi Nakamura
- Department of Chemotherapy and Mycoses, National Institute of Infectious Diseases, Toyama, Shinjuku-ku, Tokyo, Japan
- Department of Biological Science and Technology, Faculty of Industrial Science and Technology, Tokyo University of Science, Niijuku, Katsushika-ku, Tokyo, Japan
| | - Kiminori Shimizu
- Department of Biological Science and Technology, Faculty of Industrial Science and Technology, Tokyo University of Science, Niijuku, Katsushika-ku, Tokyo, Japan
| | - Satoshi Yamagoe
- Department of Chemotherapy and Mycoses, National Institute of Infectious Diseases, Toyama, Shinjuku-ku, Tokyo, Japan
| | - Yoshitsugu Miyazaki
- Department of Chemotherapy and Mycoses, National Institute of Infectious Diseases, Toyama, Shinjuku-ku, Tokyo, Japan
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Haider M, Dambuza IM, Asamaphan P, Stappers M, Reid D, Yamasaki S, Brown GD, Gow NAR, Erwig LP. The pattern recognition receptors dectin-2, mincle, and FcRγ impact the dynamics of phagocytosis of Candida, Saccharomyces, Malassezia, and Mucor species. PLoS One 2019; 14:e0220867. [PMID: 31393930 PMCID: PMC6687134 DOI: 10.1371/journal.pone.0220867] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Accepted: 07/24/2019] [Indexed: 01/15/2023] Open
Abstract
Phagocytosis is a receptor-mediated process critical to innate immune clearance of pathogens. It proceeds in a regulated sequence of stages: (a) migration of phagocytes towards pathogens, (b) recognition of PAMPs and binding through PRRs, (c) engulfment and internalisation into phagosomes, (d) phagosome maturation, and (e) killing of pathogen or host cells. However, little is known about the role that individual receptors play in these discrete stages in the recognition of fungal cells. In a previous study, we found that dectin-2 deficiency impacted some but not all stages of macrophage-mediated phagocytosis of Candida glabrata. Because the C-type lectin receptor dectin-2 critically requires coupling to the FcRγ chain for signalling, we hypothesised that this coupling may be important for regulating phagocytosis of fungal cargo. We therefore examined how deficiency in FcRγ itself or two receptors to which it couples (dectin-2 and mincle) impacts phagocytosis of six fungal organisms representing three different fungal taxa. Our data show that deficiency in these proteins impairs murine bone marrow-derived macrophage migration, engulfment, and phagosome maturation, but not macrophage survival. Therefore, FcRγ engagement with selective C-type lectin receptors (CLRs) critically affects the spatio-temporal dynamics of fungal phagocytosis.
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Affiliation(s)
- Mohammed Haider
- Medical Research Council Centre for Medical Mycology at the University of Aberdeen, Aberdeen Fungal Group, Institute of Medical Sciences, Foresterhill, Aberdeen, United Kingdom
| | - Ivy M. Dambuza
- Medical Research Council Centre for Medical Mycology at the University of Aberdeen, Aberdeen Fungal Group, Institute of Medical Sciences, Foresterhill, Aberdeen, United Kingdom
| | - Patawee Asamaphan
- Medical Research Council Centre for Medical Mycology at the University of Aberdeen, Aberdeen Fungal Group, Institute of Medical Sciences, Foresterhill, Aberdeen, United Kingdom
| | - Mark Stappers
- Medical Research Council Centre for Medical Mycology at the University of Aberdeen, Aberdeen Fungal Group, Institute of Medical Sciences, Foresterhill, Aberdeen, United Kingdom
| | - Delyth Reid
- Medical Research Council Centre for Medical Mycology at the University of Aberdeen, Aberdeen Fungal Group, Institute of Medical Sciences, Foresterhill, Aberdeen, United Kingdom
| | - Sho Yamasaki
- Division of Molecular Immunology, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Japan
- Department of Molecular Immunology, Medical Mycology Research Center, Chiba University, Chiba, Japan
| | - Gordon D. Brown
- Medical Research Council Centre for Medical Mycology at the University of Aberdeen, Aberdeen Fungal Group, Institute of Medical Sciences, Foresterhill, Aberdeen, United Kingdom
| | - Neil A. R. Gow
- Medical Research Council Centre for Medical Mycology at the University of Aberdeen, Aberdeen Fungal Group, Institute of Medical Sciences, Foresterhill, Aberdeen, United Kingdom
| | - Lars P. Erwig
- Medical Research Council Centre for Medical Mycology at the University of Aberdeen, Aberdeen Fungal Group, Institute of Medical Sciences, Foresterhill, Aberdeen, United Kingdom
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Indomethacin-induced gut damage in a surrogate insect model, Galleria mellonella. Arch Toxicol 2019; 93:2347-2360. [PMID: 31270586 DOI: 10.1007/s00204-019-02508-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Accepted: 06/26/2019] [Indexed: 12/11/2022]
Abstract
Indomethacin is a non-steroidal anti-inflammatory drug that causes gastric ulceration and increased 'leakiness' in rat models, and is used routinely as a toxicology assay to screen novel compounds for repair and restitution properties. We set out to establish conditions for indomethacin-induced gut damage in wax-moth (Galleria mellonella) larvae with a view to reducing the need for rodents in such experimentation. We administered indomethacin (0.5-7.5 µg/larva; 2-30 mg/kg) to G. mellonella via intrahaemocoelic injection and gavage (force-feeding) and monitored survival and development, blood cell (haemocyte) numbers, and changes in gut permeability. Increased levels of gut leakiness were observed within the first 4- to 24 h by tracking fluorescent microspheres in the faeces and haemolymph (blood equivalent). Additionally, we recorded varying levels of tissue damage in histological sections of the insect midgut, including epithelial sloughing and cell necrosis. Degeneration of the midgut was accompanied by significant increases in detoxification-associated activities (superoxide dismutase and glutathione-S-transferase). Herein, we present the first evidence that G. mellonella larvae force-fed indomethacin display broad symptoms of gastric damage similar to their rodent counterparts.
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Chang AL, Hole CR, Doering TL. An Automated Assay to Measure Phagocytosis of Cryptococcus neoformans. ACTA ACUST UNITED AC 2019; 53:e79. [PMID: 30802005 DOI: 10.1002/cpmc.79] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Cryptococcus neoformans is an opportunistic fungal pathogen that causes meningoencephalitis, which kills 200,000 individuals worldwide each year. It is ubiquitous in the environment and is first inhaled into the lungs of the host, where it is taken up by phagocytes. The interaction of these fungal cells with host phagocytes, therefore, is a critical step in the pathogenesis of this disease. One characteristic of this initial step in host-pathogen interactions is the avidity with which fungal cells are taken up by phagocytes, described by the phagocytic index. In this chapter, we detail a high-throughput method of directly assessing the phagocytic index of fungal cells using an imaging-based paradigm. By automating image collection and processing, this method permits rapid assessment of this critical host interaction. © 2019 by John Wiley & Sons, Inc.
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Coates CJ, Lim J, Harman K, Rowley AF, Griffiths DJ, Emery H, Layton W. The insect, Galleria mellonella, is a compatible model for evaluating the toxicology of okadaic acid. Cell Biol Toxicol 2018; 35:219-232. [PMID: 30426330 PMCID: PMC6556153 DOI: 10.1007/s10565-018-09448-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2018] [Accepted: 10/04/2018] [Indexed: 02/08/2023]
Abstract
The polyether toxin, okadaic acid, causes diarrhetic shellfish poisoning in humans. Despite extensive research into its cellular targets using rodent models, we know little about its putative effect(s) on innate immunity. We inoculated larvae of the greater wax moth, Galleria mellonella, with physiologically relevant doses of okadaic acid by direct injection into the haemocoel (body cavity) and/or gavage (force-feeding). We monitored larval survival and employed a range of cellular and biochemical assays to assess the potential harmful effects of okadaic acid. Okadaic acid at concentrations ≥ 75 ng/larva (≥ 242 μg/kg) led to significant reductions in larval survival (> 65%) and circulating haemocyte (blood cell) numbers (> 50%) within 24 h post-inoculation. In the haemolymph, okadaic acid reduced haemocyte viability and increased phenoloxidase activities. In the midgut, okadaic acid induced oxidative damage as determined by increases in superoxide dismutase activity and levels of malondialdehyde (i.e. lipid peroxidation). Our observations of insect larvae correspond broadly to data published using rodent models of shellfish-poisoning toxidrome, including complementary LD50 values: 206–242 μg/kg in mice, ~ 239 μg/kg in G. mellonella. These data support the use of this insect as a surrogate model for the investigation of marine toxins, which offers distinct ethical and financial incentives.
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Affiliation(s)
- Christopher J Coates
- Department of Biosciences, College of Science, Swansea University, Swansea, Wales, SA2 8PP, UK.
| | - Jenson Lim
- Biological and Environmental Sciences, Faculty of Natural Sciences, University of Stirling, Stirling, Scotland, FK9 4LA, UK
| | - Katie Harman
- Department of Biosciences, College of Science, Swansea University, Swansea, Wales, SA2 8PP, UK
| | - Andrew F Rowley
- Department of Biosciences, College of Science, Swansea University, Swansea, Wales, SA2 8PP, UK
| | - David J Griffiths
- Department of Biosciences, College of Science, Swansea University, Swansea, Wales, SA2 8PP, UK
| | - Helena Emery
- Department of Biosciences, College of Science, Swansea University, Swansea, Wales, SA2 8PP, UK
| | - Will Layton
- Department of Biosciences, College of Science, Swansea University, Swansea, Wales, SA2 8PP, UK
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Evans RJ, Sundaramurthy V, Frickel EM. The Interplay of Host Autophagy and Eukaryotic Pathogens. Front Cell Dev Biol 2018; 6:118. [PMID: 30271774 PMCID: PMC6146372 DOI: 10.3389/fcell.2018.00118] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 08/29/2018] [Indexed: 12/11/2022] Open
Abstract
For intracellular pathogens, host cells provide a replicative niche, but are also armed with innate defense mechanisms to combat the intruder. Co-evolution of host and pathogens has produced a complex interplay of host-pathogen interactions during infection, with autophagy emerging as a key player in the recent years. Host autophagy as a degradative process is a significant hindrance to intracellular growth of the pathogens, but also can be subverted by the pathogens to provide support such as nutrients. While the role of host cell autophagy in the pathogenesis mechanisms of several bacterial and viral pathogens have been extensively studied, less is known for eukaryotic pathogens. In this review, we focus on the interplay of host autophagy with the eukaryotic pathogens Plasmodium spp, Toxoplasma, Leishmania spp and the fungal pathogens Candida albicans, Aspergillus fumigatus and Cryptococcus neoformans. The differences between these eukaryotic pathogens in terms of the host cell types they infect, infective strategies and the host responses required to defend against them provide an interesting insight into how they respond to and interact with host cell autophagy. Due to the ability to infect multiple host species and cell types during the course of their usually complex lifestyles, autophagy plays divergent roles even for the same pathogen. The scenario is further compounded since many of the eukaryotic pathogens have their own sets of either complete or partial autophagy machinery. Eukaryotic pathogen-autophagy interplay is thus a complex relationship with many novel insights for the basic understanding of autophagy, and potential for clinical relevance.
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Affiliation(s)
- Robert J. Evans
- Host-Toxoplasma Interaction Laboratory, The Francis Crick Institute, London, United Kingdom
| | | | - Eva-Maria Frickel
- Host-Toxoplasma Interaction Laboratory, The Francis Crick Institute, London, United Kingdom
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