1
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Sonnberger J, Kasper L, Lange T, Brunke S, Hube B. "We've got to get out"-Strategies of human pathogenic fungi to escape from phagocytes. Mol Microbiol 2024; 121:341-358. [PMID: 37800630 DOI: 10.1111/mmi.15149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 08/08/2023] [Accepted: 08/16/2023] [Indexed: 10/07/2023]
Abstract
Human fungal pathogens are a deadly and underappreciated risk to global health that most severely affect immunocompromised individuals. A virulence attribute shared by some of the most clinically relevant fungal species is their ability to survive inside macrophages and escape from these immune cells. In this review, we discuss the mechanisms behind intracellular survival and elaborate how escape is mediated by lytic and non-lytic pathways as well as strategies to induce programmed host cell death. We also discuss persistence as an alternative to rapid host cell exit. In the end, we address the consequences of fungal escape for the host immune response and provide future perspectives for research and development of targeted therapies.
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Affiliation(s)
- Johannes Sonnberger
- Department of Microbial Pathogenicity Mechanisms, Hans Knoell Institute, Jena, Germany
| | - Lydia Kasper
- Department of Microbial Pathogenicity Mechanisms, Hans Knoell Institute, Jena, Germany
| | - Theresa Lange
- Department of Microbial Pathogenicity Mechanisms, Hans Knoell Institute, Jena, Germany
| | - Sascha Brunke
- Department of Microbial Pathogenicity Mechanisms, Hans Knoell Institute, Jena, Germany
| | - Bernhard Hube
- Department of Microbial Pathogenicity Mechanisms, Hans Knoell Institute, Jena, Germany
- Institute of Microbiology, Friedrich Schiller University, Jena, Germany
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2
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Albuquerque P, de Sousa HR, de Oliveira Frazão S, do Nascimento Miranda LV, Paes HC, Pereira IS, Nicola AM. Measuring Laccase Activity and Melanin Production in Cryptococcus neoformans. Methods Mol Biol 2024; 2775:257-268. [PMID: 38758323 DOI: 10.1007/978-1-0716-3722-7_17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/18/2024]
Abstract
Melanin is a complex dark pigment synthetized by the phenoloxidase enzyme laccase in Cryptococcus neoformans. In vitro, this enzyme oxidizes exogenous catecholamines to produce melanin that may be secreted or incorporated into the fungal cell wall. This pigment has multiple roles in C. neoformans virulence during its interaction with different hosts and probably also in protecting fungal cells in the environment against predation and oxidative and radiation stresses, among others. However, it is important to note that laccase also has melanin-independent roles in C. neoformans interactions with host cells. In this chapter, we describe a quantitative laccase assay and a method for evaluating the kinetics of melanin production in C. neoformans colonies.
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Affiliation(s)
| | | | | | | | - Hugo Costa Paes
- Faculty of Medicine, University of Brasília, Brasília, DF, Brazil
| | - Ildinete Silva Pereira
- Institute of Biology, Department of Cell Biology, University of Brasília, Brasília, DF, Brazil
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3
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Rocha AP, Alves TS, Caixeta AV, Albuquerque P, Nicola AM. Interaction Between Macrophages and Cryptococcus neoformans: Distinguishing Phagocytosed Versus External Fungi. Methods Mol Biol 2024; 2775:171-193. [PMID: 38758318 DOI: 10.1007/978-1-0716-3722-7_12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/18/2024]
Abstract
The interaction between macrophages and Cryptococcus neoformans is crucial in the pathogenesis of cryptococcosis. These phagocytes are important immune effectors, but also a niche in which facultative intracellular parasites, such as C. neoformans, thrive. Consequently, phagocytosis of cryptococcal cells and its outcomes are very frequently studied. One major issue with several of the tests used for this, however, is that macrophage-C. neoformans interaction does not always result in phagocytosis, as fungi may be attached to the external surface of the phagocyte. The most used methodologies to study phagocytosis of cryptococcal cells have varying degrees of precision in separating fungi that are truly internalized from those that are outside macrophages. Here we describe two assays to measure phagocytosis that can differentiate internal from external C. neoformans cells.
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4
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Pacifici N, Rojalin T, Carney RP, Lewis JS. A Multi-Fluorophore Staining Scheme for Identification and Quantification of Vomocytosis. CHEMICAL & BIOMEDICAL IMAGING 2023; 1:725-737. [PMID: 38037611 PMCID: PMC10685718 DOI: 10.1021/cbmi.3c00050] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Revised: 07/24/2023] [Accepted: 07/26/2023] [Indexed: 12/02/2023]
Abstract
Vomocytosis is a process by which fungal pathogens, for instance, Cryptococcus neoformans (CN), escape from the digestive phagolysosome of phagocytic cells after ingestion. Interestingly, this expulsion leaves both the pathogen and phagocyte unharmed, and is believed to be an important mechanism by which CNs disseminate throughout infected hosts. This phenomenon was discovered in 2006, and research to date has relied almost entirely on quantification via manual counting of vomocytosis events in time-lapse microscopy videos. This archaic method has the significant disadvantages of requiring excessive labor in manual analysis, limited throughput capabilities, and low accuracy due to subjectivity. Here, we present an alternative method to measure vomocytosis rates using a multi-fluorophore reporter system comprised of two in situ staining steps during infection and a flow cytometry readout. This approach overcomes the limitations of conventional time lapse microscopy methods, with key advantages of high throughput capability, simple procedural steps, and accurate objective readouts. This study rigorously characterizes this vomocytosis reporter system in CN-infected MΦ and DC cultures via fluorescence microscopy, confocal microscopy, and flow cytometry. Here, this fluorescent tool is used to observe differences in expulsion rates after phagosome-modifying drug treatments and additionally utilized to distinguish differences in biochemical compositions among fluorescence-activated cell sorted fungal populations via Raman spectroscopy. Furthermore, this reporter scheme is demonstrated to be adaptable for use in measuring potential biomaterial particle expulsion events. Ultimately, the fluorescent reporter system presented here provides a universal tool for vomocytosis rate measurement of phagocytosed material. This facile approach opens the door to previously unfeasible types of vomocytosis-related studies such as high throughput treatment mechanistic screening and downstream characterization of expelled material.
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Affiliation(s)
- Noah Pacifici
- Department
of Biomedical Engineering, University of
California-Davis, Davis, California 95616, United States
| | - Tatu Rojalin
- Department
of Biomedical Engineering, University of
California-Davis, Davis, California 95616, United States
| | - Randy P. Carney
- Department
of Biomedical Engineering, University of
California-Davis, Davis, California 95616, United States
| | - Jamal S. Lewis
- Department
of Biomedical Engineering, University of
California-Davis, Davis, California 95616, United States
- J.
Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, Florida 32611, United States
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5
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Romero V, Kalinhoff C, Saa LR, Sánchez A. Fungi's Swiss Army Knife: Pleiotropic Effect of Melanin in Fungal Pathogenesis during Cattle Mycosis. J Fungi (Basel) 2023; 9:929. [PMID: 37755037 PMCID: PMC10532448 DOI: 10.3390/jof9090929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 09/05/2023] [Accepted: 09/08/2023] [Indexed: 09/28/2023] Open
Abstract
Fungal threats to public health, food security, and biodiversity have escalated, with a significant rise in mycosis cases globally. Around 300 million people suffer from severe fungal diseases annually, while one-third of food crops are decimated by fungi. Vertebrate, including livestock, are also affected. Our limited understanding of fungal virulence mechanisms hampers our ability to prevent and treat cattle mycoses. Here we aim to bridge knowledge gaps in fungal virulence factors and the role of melanin in evading bovine immune responses. We investigate mycosis in bovines employing a PRISMA-based methodology, bioinformatics, and data mining techniques. Our analysis identified 107 fungal species causing mycoses, primarily within the Ascomycota division. Candida, Aspergillus, Malassezia, and Trichophyton were the most prevalent genera. Of these pathogens, 25% produce melanin. Further research is required to explore the involvement of melanin and develop intervention strategies. While the literature on melanin-mediated fungal evasion mechanisms in cattle is lacking, we successfully evaluated the transferability of immunological mechanisms from other model mammals through homology. Bioinformatics enables knowledge transfer and enhances our understanding of mycosis in cattle. This synthesis fills critical information gaps and paves the way for proposing biotechnological strategies to mitigate the impact of mycoses in cattle.
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Affiliation(s)
- Víctor Romero
- Maestría en Biotecnología Agropecuaria, Universidad Técnica Particular de Loja, San Cayetano Alto, Calle París s/n, Loja 1101608, Ecuador
- Museo de Zoología, Universidad Técnica Particular de Loja, San Cayetano Alto, Calle París s/n, Loja 1101608, Ecuador
| | - Carolina Kalinhoff
- Departamento de Ciencias Biológicas y Agropecuarias, Facultad de Ciencias Exactas y Naturales, Universidad Técnica Particular de Loja, San Cayetano Alto, Calle París s/n, Loja 1101608, Ecuador; (C.K.)
| | - Luis Rodrigo Saa
- Departamento de Ciencias Biológicas y Agropecuarias, Facultad de Ciencias Exactas y Naturales, Universidad Técnica Particular de Loja, San Cayetano Alto, Calle París s/n, Loja 1101608, Ecuador; (C.K.)
| | - Aminael Sánchez
- Departamento de Ciencias Biológicas y Agropecuarias, Facultad de Ciencias Exactas y Naturales, Universidad Técnica Particular de Loja, San Cayetano Alto, Calle París s/n, Loja 1101608, Ecuador; (C.K.)
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6
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Stuckey PV, Santiago-Tirado FH. Fungal mechanisms of intracellular survival: what can we learn from bacterial pathogens? Infect Immun 2023; 91:e0043422. [PMID: 37506189 PMCID: PMC10501222 DOI: 10.1128/iai.00434-22] [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: 11/28/2022] [Accepted: 06/23/2023] [Indexed: 07/30/2023] Open
Abstract
Fungal infections represent a major, albeit neglected, public health threat with serious medical and economic burdens globally. With unacceptably high mortality rates, invasive fungal pathogens are responsible for millions of deaths each year, with a steadily increasing incidence primarily in immunocompromised individuals. The poor therapeutic options and rise of antifungal drug resistance pose further challenges in controlling these infections. These fungal pathogens have adapted to survive within mammalian hosts and can establish intracellular niches to promote survival within host immune cells. To do that, they have developed diverse methods to circumvent the innate immune system attack. This includes strategies such as altering their morphology, counteracting macrophage antimicrobial action, and metabolic adaptation. This is reminiscent of how bacterial pathogens have adapted to survive within host cells and cause disease. However, relative to the great deal of information available concerning intracellular bacterial pathogenesis, less is known about the mechanisms fungal pathogens employ. Therefore, here we review our current knowledge and recent advances in our understanding of how fungi can evade and persist within host immune cells. This review will focus on the major fungal pathogens, including Cryptococcus neoformans, Candida albicans, and Aspergillus fumigatus, among others. As we discover and understand the strategies used by these fungi, similarities with their bacterial counterparts are becoming apparent, hence we can use the abundant information from bacteria to guide our studies in fungi. By understanding these strategies, new lines of research will open that can improve the treatments of these devastating fungal diseases.
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Affiliation(s)
- Peter V. Stuckey
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA
| | - Felipe H. Santiago-Tirado
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA
- Eck Institute for Global Health, University of Notre Dame, Notre Dame, Indiana, USA
- Warren Center for Drug Discovery, University of Notre Dame, Notre Dame, Indiana, USA
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7
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Jackson KM, Ding M, Nielsen K. Importance of Clinical Isolates in Cryptococcus neoformans Research. J Fungi (Basel) 2023; 9:364. [PMID: 36983532 PMCID: PMC10056780 DOI: 10.3390/jof9030364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 03/09/2023] [Accepted: 03/13/2023] [Indexed: 03/19/2023] Open
Abstract
The human pathogenic fungus Cryptococcus neoformans is a global health concern. Previous research in the field has focused on studies using reference strains to identify virulence factors, generate mutant libraries, define genomic structures, and perform functional studies. In this review, we discuss the benefits and drawbacks of using reference strains to study C. neoformans, describe how the study of clinical isolates has expanded our understanding of pathogenesis, and highlight how studies using clinical isolates can further develop our understanding of the host-pathogen interaction during C. neoformans infection.
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Affiliation(s)
| | | | - Kirsten Nielsen
- Department of Microbiology and Immunology, University of Minnesota, Minneapolis, MN 55455, USA
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8
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Cryptococcus neoformans Infection in the Central Nervous System: The Battle between Host and Pathogen. J Fungi (Basel) 2022; 8:jof8101069. [PMID: 36294634 PMCID: PMC9605252 DOI: 10.3390/jof8101069] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Revised: 09/28/2022] [Accepted: 10/07/2022] [Indexed: 11/17/2022] Open
Abstract
Cryptococcus neoformans (C. neoformans) is a pathogenic fungus with a global distribution. Humans become infected by inhaling the fungus from the environment, and the fungus initially colonizes the lungs. If the immune system fails to contain C. neoformans in the lungs, the fungus can disseminate to the blood and invade the central nervous system, resulting in fatal meningoencephalitis particularly in immunocompromised individuals including HIV/AIDS patients. Following brain invasion, C. neoformans will encounter host defenses involving resident as well as recruited immune cells in the brain. To overcome host defenses, C. neoformans possesses multiple virulence factors capable of modulating immune responses. The outcome of the interactions between the host and C. neoformans will determine the disease progression. In this review, we describe the current understanding of how C. neoformans migrates to the brain across the blood–brain barrier, and how the host immune system responds to the invading organism in the brain. We will also discuss the virulence factors that C. neoformans uses to modulate host immune responses.
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9
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Pathogenesis of Fungal Infections in the Central Nervous System: Host and Pathogen Factors in Neurotropism. CURRENT FUNGAL INFECTION REPORTS 2022. [DOI: 10.1007/s12281-022-00444-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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10
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Structural Properties, Genomic Distribution of Laccases from Streptomyces and Their Potential Applications. Process Biochem 2022. [DOI: 10.1016/j.procbio.2022.04.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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11
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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: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [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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12
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Zamith-Miranda D, Peres da Silva R, Couvillion SP, Bredeweg EL, Burnet MC, Coelho C, Camacho E, Nimrichter L, Puccia R, Almeida IC, Casadevall A, Rodrigues ML, Alves LR, Nosanchuk JD, Nakayasu ES. Omics Approaches for Understanding Biogenesis, Composition and Functions of Fungal Extracellular Vesicles. Front Genet 2021; 12:648524. [PMID: 34012462 PMCID: PMC8126698 DOI: 10.3389/fgene.2021.648524] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Accepted: 04/06/2021] [Indexed: 12/13/2022] Open
Abstract
Extracellular vesicles (EVs) are lipid bilayer structures released by organisms from all kingdoms of life. The diverse biogenesis pathways of EVs result in a wide variety of physical properties and functions across different organisms. Fungal EVs were first described in 2007 and different omics approaches have been fundamental to understand their composition, biogenesis, and function. In this review, we discuss the role of omics in elucidating fungal EVs biology. Transcriptomics, proteomics, metabolomics, and lipidomics have each enabled the molecular characterization of fungal EVs, providing evidence that these structures serve a wide array of functions, ranging from key carriers of cell wall biosynthetic machinery to virulence factors. Omics in combination with genetic approaches have been instrumental in determining both biogenesis and cargo loading into EVs. We also discuss how omics technologies are being employed to elucidate the role of EVs in antifungal resistance, disease biomarkers, and their potential use as vaccines. Finally, we review recent advances in analytical technology and multi-omic integration tools, which will help to address key knowledge gaps in EVs biology and translate basic research information into urgently needed clinical applications such as diagnostics, and immuno- and chemotherapies to fungal infections.
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Affiliation(s)
- Daniel Zamith-Miranda
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, United States
- Division of Infectious Diseases, Department of Medicine, Albert Einstein College of Medicine, Bronx, NY, United States
| | | | - Sneha P. Couvillion
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA, United States
| | - Erin L. Bredeweg
- Environmental and Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA, United States
| | - Meagan C. Burnet
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA, United States
| | - Carolina Coelho
- MRC Centre for Medical Mycology, University of Exeter, Exeter, United Kingdom
| | - Emma Camacho
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States
| | - Leonardo Nimrichter
- Laboratório de Glicobiologia de Eucariotos, Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Rosana Puccia
- Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina-Universidade Federal de São Paulo, São Paulo, Brazil
| | - Igor C. Almeida
- Department of Biological Sciences, Border Biomedical Research Center, University of Texas at El Paso, El Paso, TX, United States
| | - Arturo Casadevall
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States
| | - Marcio L. Rodrigues
- Laboratório de Regulação da Expressão Gênica, Instituto Carlos Chagas-FIOCRUZ PR, Curitiba, Brazil
- Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Lysangela R. Alves
- Laboratório de Regulação da Expressão Gênica, Instituto Carlos Chagas-FIOCRUZ PR, Curitiba, Brazil
| | - Joshua D. Nosanchuk
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, United States
- Division of Infectious Diseases, Department of Medicine, Albert Einstein College of Medicine, Bronx, NY, United States
| | - Ernesto S. Nakayasu
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA, United States
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13
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de Sousa HR, de Frazão S, de Oliveira Júnior GP, Albuquerque P, Nicola AM. Cryptococcal Virulence in Humans: Learning From Translational Studies With Clinical Isolates. Front Cell Infect Microbiol 2021; 11:657502. [PMID: 33968804 PMCID: PMC8097041 DOI: 10.3389/fcimb.2021.657502] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Accepted: 03/31/2021] [Indexed: 01/17/2023] Open
Abstract
Cryptococcosis, an invasive mycosis caused by Cryptococcus spp, kills between 20% and 70% of the patients who develop it. There are no vaccines for prevention, and treatment is based on a limited number of antifungals. Studying fungal virulence and how the host responds to infection could lead to new therapies, improving outcomes for patients. The biggest challenge, however, is that experimental cryptococcosis models do not completely recapitulate human disease, while human experiments are limited due to ethical reasons. To overcome this challenge, one of the approaches used by researchers and clinicians is to: 1) collect cryptococcal clinical isolates and associated patient data; 2) study the set of isolates in the laboratory (virulence and host-pathogen interaction variables, molecular markers); 3) correlate the laboratory and patient data to understand the roles fungal attributes play in the human disease. Here we review studies that have shed light on the cryptococcosis pathophysiology using these approaches, with a special focus on human disease. Isolates that more effectively evade macrophage responses, that secrete more laccase, melanize faster and have larger capsules in the cerebrospinal fluid are associated with poorer patient outcomes. Additionally, molecular studies have also shown that cryptococcal clades vary in virulence, with clinical impact. Limitations of those studies include the use of a small number of isolates or retrospectively collected clinical data. The fact that they resulted in very important information is a reflection of the impact this strategy has in understanding cryptococcosis and calls for international collaboration that could boost our knowledge.
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Affiliation(s)
- Herdson Renney de Sousa
- Microbiology, Immunology and Biotechnology Laboratory, Faculty of Medicine, University of Brasília, Brasília, Brazil
| | - Stefânia de Frazão
- Laboratory of Molecular Biology of Pathogenic Fungi, Department of Cell Biology, Institute of Biological Sciences, University of Brasília, Brasília, Brazil
| | - Getúlio Pereira de Oliveira Júnior
- Division of Allergy and Inflammation, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States
| | - Patrícia Albuquerque
- Microbiology, Immunology and Biotechnology Laboratory, Faculty of Medicine, University of Brasília, Brasília, Brazil
- Laboratory of Molecular Biology of Pathogenic Fungi, Department of Cell Biology, Institute of Biological Sciences, University of Brasília, Brasília, Brazil
- Faculty of Ceilândia, University of Brasília, Brasília, Brazil
| | - André Moraes Nicola
- Microbiology, Immunology and Biotechnology Laboratory, Faculty of Medicine, University of Brasília, Brasília, Brazil
- Graduate Program in Genomic Sciences and Biotechnology, Catholic University of Brasília, Brasília, Brazil
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14
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Liu S, Youngchim S, Zamith-Miranda D, Nosanchuk JD. Fungal Melanin and the Mammalian Immune System. J Fungi (Basel) 2021; 7:jof7040264. [PMID: 33807336 PMCID: PMC8066723 DOI: 10.3390/jof7040264] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 03/25/2021] [Accepted: 03/26/2021] [Indexed: 02/06/2023] Open
Abstract
Melanins are ubiquitous complex polymers that are commonly known in humans to cause pigmentation of our skin. Melanins are also present in bacteria, fungi, and helminths. In this review, we will describe the diverse interactions of fungal melanin with the mammalian immune system. We will particularly focus on Cryptococcus neoformans and also discuss other major melanotic pathogenic fungi. Melanin interacts with the immune system through diverse pathways, reducing the effectiveness of phagocytic cells, binding effector molecules and antifungals, and modifying complement and antibody responses.
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Affiliation(s)
- Sichen Liu
- Department of Medicine, Albert Einstein College of Medicine, Bronx, NY 10461, USA; (S.L.); (D.Z.-M.)
| | - Sirida Youngchim
- Department of Microbiology, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand;
| | - Daniel Zamith-Miranda
- Department of Medicine, Albert Einstein College of Medicine, Bronx, NY 10461, USA; (S.L.); (D.Z.-M.)
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Joshua D. Nosanchuk
- Department of Medicine, Albert Einstein College of Medicine, Bronx, NY 10461, USA; (S.L.); (D.Z.-M.)
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
- Correspondence:
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15
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Associations between Cryptococcus Genotypes, Phenotypes, and Clinical Parameters of Human Disease: A Review. J Fungi (Basel) 2021; 7:jof7040260. [PMID: 33808500 PMCID: PMC8067209 DOI: 10.3390/jof7040260] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 03/25/2021] [Accepted: 03/25/2021] [Indexed: 12/11/2022] Open
Abstract
The genus Cryptococcus contains two primary species complexes that are significant opportunistic human fungal pathogens: C. neoformans and C. gattii. In humans, cryptococcosis can manifest in many ways, but most often results in either pulmonary or central nervous system disease. Patients with cryptococcosis can display a variety of symptoms on a spectrum of severity because of the interaction between yeast and host. The bulk of our knowledge regarding Cryptococcus and the mechanisms of disease stem from in vitro experiments and in vivo animal models that make a fair attempt, but do not recapitulate the conditions inside the human host. To better understand the dynamics of initiation and progression in cryptococcal disease, it is important to study the genetic and phenotypic differences in the context of human infection to identify the human and fungal risk factors that contribute to pathogenesis and poor clinical outcomes. In this review, we summarize the current understanding of the different clinical presentations and health outcomes that are associated with pathogenicity and virulence of cryptococcal strains with respect to specific genotypes and phenotypes.
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16
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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] [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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