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Dao A, Kim HY, Garnham K, Kidd S, Sati H, Perfect J, Sorrell TC, Harrison T, Rickerts V, Gigante V, Alastruey-Izquierdo A, Alffenaar JW, Morrissey CO, Chen SCA, Beardsley J. Cryptococcosis-a systematic review to inform the World Health Organization Fungal Priority Pathogens List. Med Mycol 2024; 62:myae043. [PMID: 38935902 PMCID: PMC11210623 DOI: 10.1093/mmy/myae043] [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: 09/11/2023] [Revised: 12/01/2023] [Accepted: 04/27/2024] [Indexed: 06/29/2024] Open
Abstract
Cryptococcosis causes a high burden of disease worldwide. This systematic review summarizes the literature on Cryptococcus neoformans and C. gattii infections to inform the World Health Organization's first Fungal Priority Pathogen List. PubMed and Web of Science were used to identify studies reporting on annual incidence, mortality, morbidity, antifungal resistance, preventability, and distribution/emergence in the past 10 years. Mortality rates due to C. neoformans were 41%-61%. Complications included acute renal impairment, raised intracranial pressure needing shunts, and blindness. There was moderate evidence of reduced susceptibility (MIC range 16-32 mg/l) of C. neoformans to fluconazole, itraconazole, ketoconazole, voriconazole, and amphotericin B. Cryptococcus gattii infections comprised 11%-33% of all cases of invasive cryptococcosis globally. The mortality rates were 10%-23% for central nervous system (CNS) and pulmonary infections, and ∼43% for bloodstream infections. Complications described included neurological sequelae (17%-27% in C. gattii infections) and immune reconstitution inflammatory syndrome. MICs were generally low for amphotericin B (MICs: 0.25-0.5 mg/l), 5-flucytosine (MIC range: 0.5-2 mg/l), itraconazole, posaconazole, and voriconazole (MIC range: 0.06-0.5 mg/l). There is a need for increased surveillance of disease phenotype and outcome, long-term disability, and drug susceptibility to inform robust estimates of disease burden.
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Affiliation(s)
- Aiken Dao
- Sydney Infectious Diseases Institute, The University of Sydney, Sydney, Australia
- Westmead Institute for Medical Research, Westmead, Sydney, Australia
- Westmead Clinical School, Westmead Hospital, Sydney, Australia
| | - Hannah Yejin Kim
- Sydney Infectious Diseases Institute, The University of Sydney, Sydney, Australia
- Sydney Pharmacy School, Faculty of Medicine and Health, The University of Sydney, Camperdown, Australia
- Department of Pharmacy, Westmead Hospital, Westmead, Australia
| | - Katherine Garnham
- Sydney Infectious Diseases Institute, The University of Sydney, Sydney, Australia
- Sunshine Coast University Hospital, Birtinya, Qld 4575, Australia
| | - Sarah Kidd
- National Mycology Reference Centre, Microbiology and Infectious Diseases, SA Pathology, Adelaide, Australia
| | - Hatim Sati
- AMR Division, World Health Organization, Geneva, Switzerland
| | | | - Tania C Sorrell
- Sydney Infectious Diseases Institute, The University of Sydney, Sydney, Australia
- Westmead Institute for Medical Research, Westmead, Sydney, Australia
- Westmead Clinical School, Westmead Hospital, Sydney, Australia
| | - Thomas Harrison
- Institute of Infection and Immunity, St George’s University London, London, UK
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, UK
| | | | - Valeria Gigante
- AMR Division, World Health Organization, Geneva, Switzerland
| | - Ana Alastruey-Izquierdo
- Mycology Reference Laboratory, National Centre for Microbiology, Instituto de Salud Carlos III, Madrid, Spain
| | - Jan-Willem Alffenaar
- Sydney Infectious Diseases Institute, The University of Sydney, Sydney, Australia
- Westmead Clinical School, Westmead Hospital, Sydney, Australia
- Sydney Pharmacy School, Faculty of Medicine and Health, The University of Sydney, Camperdown, Australia
| | - C Orla Morrissey
- Department of Infectious Diseases, Alfred Health, Melbourne, Australia
- Monash University, Department of Infectious Diseases, Melbourne, Victoria, Australia
| | - Sharon C-A Chen
- Centre for Infectious Diseases and Microbiology Laboratory Services, Institute of Clinical Pathology and Medical Research, New South Wales Health Pathology, Westmead Hospital, Westmead, Sydney, Australia
| | - Justin Beardsley
- Sydney Infectious Diseases Institute, The University of Sydney, Sydney, Australia
- Westmead Institute for Medical Research, Westmead, Sydney, Australia
- Westmead Clinical School, Westmead Hospital, Sydney, Australia
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Angers I, Akik W, Beauchamp A, King IL, Lands LC, Qureshi ST. Card9 Broadly Regulates Host Immunity against Experimental Pulmonary Cryptococcus neoformans 52D Infection. J Fungi (Basel) 2024; 10:434. [PMID: 38921420 PMCID: PMC11204891 DOI: 10.3390/jof10060434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2024] [Revised: 06/01/2024] [Accepted: 06/07/2024] [Indexed: 06/27/2024] Open
Abstract
The ubiquitous soil-associated fungus Cryptococcus neoformans causes pneumonia that may progress to fatal meningitis. Recognition of fungal cell walls by C-type lectin receptors (CLRs) has been shown to trigger the host immune response. Caspase recruitment domain-containing protein 9 (Card9) is an intracellular adaptor that is downstream of several CLRs. Experimental studies have implicated Card9 in host resistance against C. neoformans; however, the mechanisms that are associated with susceptibility to progressive infection are not well defined. To further characterize the role of Card9 in cryptococcal infection, Card9em1Sq mutant mice that lack exon 2 of the Card9 gene on the Balb/c genetic background were created using CRISPR-Cas9 genome editing technology and intratracheally infected with C. neoformans 52D. Card9em1Sq mice had significantly higher lung and brain fungal burdens and shorter survival after C. neoformans 52D infection. Susceptibility of Card9em1Sq mice was associated with lower pulmonary cytokine and chemokine production, as well as reduced numbers of CD4+ lymphocytes, neutrophils, monocytes, and dendritic cells in the lungs. Histological analysis and intracellular cytokine staining of CD4+ T cells demonstrated a Th2 pattern of immunity in Card9em1Sq mice. These findings demonstrate that Card9 broadly regulates the host inflammatory and immune response to experimental pulmonary infection with a moderately virulent strain of C. neoformans.
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Affiliation(s)
- Isabelle Angers
- Translational Research in Respiratory Diseases Program, Research Institute of the McGill University Health Centre, McGill University, Montreal, QC H4A 3J1, Canada; (I.A.); (W.A.); (A.B.); (I.L.K.); (L.C.L.)
| | - Wided Akik
- Translational Research in Respiratory Diseases Program, Research Institute of the McGill University Health Centre, McGill University, Montreal, QC H4A 3J1, Canada; (I.A.); (W.A.); (A.B.); (I.L.K.); (L.C.L.)
- Meakins-Christie Laboratories, Division of Experimental Medicine, McGill University, Montreal, QC H4A 3J1, Canada
| | - Annie Beauchamp
- Translational Research in Respiratory Diseases Program, Research Institute of the McGill University Health Centre, McGill University, Montreal, QC H4A 3J1, Canada; (I.A.); (W.A.); (A.B.); (I.L.K.); (L.C.L.)
| | - Irah L. King
- Translational Research in Respiratory Diseases Program, Research Institute of the McGill University Health Centre, McGill University, Montreal, QC H4A 3J1, Canada; (I.A.); (W.A.); (A.B.); (I.L.K.); (L.C.L.)
- Meakins-Christie Laboratories, Department of Microbiology and Immunology, McGill University, Montreal, QC H4A 3J1, Canada
| | - Larry C. Lands
- Translational Research in Respiratory Diseases Program, Research Institute of the McGill University Health Centre, McGill University, Montreal, QC H4A 3J1, Canada; (I.A.); (W.A.); (A.B.); (I.L.K.); (L.C.L.)
- Meakins-Christie Laboratories, Department of Pediatrics, McGill University, Montreal, QC H4A 3J1, Canada
| | - Salman T. Qureshi
- Translational Research in Respiratory Diseases Program, Research Institute of the McGill University Health Centre, McGill University, Montreal, QC H4A 3J1, Canada; (I.A.); (W.A.); (A.B.); (I.L.K.); (L.C.L.)
- Meakins-Christie Laboratories, Department of Medicine, McGill University, Montreal, QC H4A 3J1, Canada
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Thambugala KM, Daranagama DA, Tennakoon DS, Jayatunga DPW, Hongsanan S, Xie N. Humans vs. Fungi: An Overview of Fungal Pathogens against Humans. Pathogens 2024; 13:426. [PMID: 38787278 PMCID: PMC11124197 DOI: 10.3390/pathogens13050426] [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: 03/28/2024] [Revised: 05/14/2024] [Accepted: 05/15/2024] [Indexed: 05/25/2024] Open
Abstract
Human fungal diseases are infections caused by any fungus that invades human tissues, causing superficial, subcutaneous, or systemic diseases. Fungal infections that enter various human tissues and organs pose a significant threat to millions of individuals with weakened immune systems globally. Over recent decades, the reported cases of invasive fungal infections have increased substantially and research progress in this field has also been rapidly boosted. This review provides a comprehensive list of human fungal pathogens extracted from over 850 recent case reports, and a summary of the relevant disease conditions and their origins. Details of 281 human fungal pathogens belonging to 12 classes and 104 genera in the divisions ascomycota, basidiomycota, entomophthoromycota, and mucoromycota are listed. Among these, Aspergillus stands out as the genus with the greatest potential of infecting humans, comprising 16 species known to infect humans. Additionally, three other genera, Curvularia, Exophiala, and Trichophyton, are recognized as significant genera, each comprising 10 or more known human pathogenic species. A phylogenetic analysis based on partial sequences of the 28S nrRNA gene (LSU) of human fungal pathogens was performed to show their phylogenetic relationships and clarify their taxonomies. In addition, this review summarizes the recent advancements in fungal disease diagnosis and therapeutics.
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Affiliation(s)
- Kasun M. Thambugala
- Genetics and Molecular Biology Unit, Faculty of Applied Sciences, University of Sri Jayewardenepura, Gangodawila, Nugegoda 10250, Sri Lanka; (K.M.T.); (D.P.W.J.)
- Center for Biotechnology, Department of Zoology, University of Sri Jayewardenepura, Nugegoda 10250, Sri Lanka
- Center for Plant Materials and Herbal Products Research, University of Sri Jayewardenepura, Nugegoda 10250, Sri Lanka
| | - Dinushani A. Daranagama
- Department of Plant and Molecular Biology, Faculty of Science, University of Kelaniya, Kelaniya 11300, Sri Lanka;
| | - Danushka S. Tennakoon
- Bioengineering and Technological Research Centre for Edible and Medicinal Fungi, Jiangxi Agricultural University, Nanchang 330045, China;
| | - Dona Pamoda W. Jayatunga
- Genetics and Molecular Biology Unit, Faculty of Applied Sciences, University of Sri Jayewardenepura, Gangodawila, Nugegoda 10250, Sri Lanka; (K.M.T.); (D.P.W.J.)
- Center for Biotechnology, Department of Zoology, University of Sri Jayewardenepura, Nugegoda 10250, Sri Lanka
- Center for Plant Materials and Herbal Products Research, University of Sri Jayewardenepura, Nugegoda 10250, Sri Lanka
| | - Sinang Hongsanan
- Shenzhen Key Laboratory of Microbial Genetic Engineering, College of Life Science and Oceanography, Shenzhen University, Shenzhen 518060, China
| | - Ning Xie
- Shenzhen Key Laboratory of Microbial Genetic Engineering, College of Life Science and Oceanography, Shenzhen University, Shenzhen 518060, China
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Tang S, Hao R, Liu X, He H, Tian Y, Jing T, Liu Z, Xu Y, Li X. Global trends in Cryptococcus and its interactions with the host immune system: a bibliometric analysis. Front Immunol 2024; 15:1397338. [PMID: 38774865 PMCID: PMC11106374 DOI: 10.3389/fimmu.2024.1397338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2024] [Accepted: 04/18/2024] [Indexed: 05/24/2024] Open
Abstract
Objectives This manuscript undertakes a systematic examination of the research landscape concerning global Cryptococcus species and their dynamism with the host immune system spanning the past decade. It furnishes a detailed survey of leading knowledge institutions and critical focal points in this area, utilizing bibliometric analysis. Methods VOSviewer and CiteSpace software platforms were employed to systematically analyze and graphically depict the relevant literature indexed in the WoSCC database over the preceding ten years. Results In the interval between October 1, 2013, and October 1, 2023, a corpus of 795 publications was amassed. The primary research institutions involved in this study include Duke University, the University of Minnesota, and the University of Sydney. The leading trio of nations, in terms of publication volume, comprises the United States, China, and Brazil. Among the most prolific authors are Casadevall, Arturo; Wormley, Floyd L., Jr.; and Olszewski, Michal A., with the most highly cited author being Perfect, Jr. The most esteemed journal is Mbio, while Infection and Immunity commands the highest citation frequency, and the Journal of Clinical Microbiology boasts the most significant impact factor. Present research foci encompass the intricate interactions between Cryptococcus pathogenesis and host immunity, alongside immune mechanisms, complications, and immunotherapies. Conclusion This represents the first exhaustive scholarly review and bibliometric scrutiny of the evolving landscapes in Cryptococcus research and its interactions with the host immune system. The analyses delineated herein provide insights into prevailing research foci and trajectories, thus furnishing critical directions for subsequent inquiries in this domain.
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Affiliation(s)
- Shiqin Tang
- School of Clinical Medicine, The Hebei University of Engineering, Handan, Hebei, China
| | - Ruiying Hao
- School of Clinical Medicine, The Hebei University of Engineering, Handan, Hebei, China
| | - Xin Liu
- Handan Stomatological Hospital, Endodontics, Handan, Hebei, China
| | - Huina He
- School of Clinical Medicine, The Hebei University of Engineering, Handan, Hebei, China
| | - Yanan Tian
- School of Clinical Medicine, The Hebei University of Engineering, Handan, Hebei, China
| | - Tingting Jing
- Department of Dermatology, Affiliated Hospital of Hebei University of Engineering, Handan, Hebei, China
| | - Zhao Liu
- Department of Dermatology, Affiliated Hospital of Hebei University of Engineering, Handan, Hebei, China
| | - Yanyan Xu
- Department of Dermatology, Affiliated Hospital of Hebei University of Engineering, Handan, Hebei, China
| | - Xiaojing Li
- School of Clinical Medicine, The Hebei University of Engineering, Hebei Key Laboratory of Immunological Dermatology, Handan, Hebei, China
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Hester MM, Carlson D, Lodge JK, Levitz SM, Specht CA. Immune evasion by Cryptococcus gattii in vaccinated mice coinfected with C. neoformans. Front Immunol 2024; 15:1356651. [PMID: 38469300 PMCID: PMC10925662 DOI: 10.3389/fimmu.2024.1356651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Accepted: 02/05/2024] [Indexed: 03/13/2024] Open
Abstract
Cryptococcus neoformans and C. gattii, the etiologic agents of cryptococcosis, cause over 100,000 deaths worldwide every year, yet no cryptococcal vaccine has progressed to clinical trials. In preclinical studies, mice vaccinated with an attenuated strain of C. neoformans deleted of three cryptococcal chitin deacetylases (Cn-cda1Δ2Δ3Δ) were protected against a lethal challenge with C. neoformans strain KN99. While Cn-cda1Δ2Δ3Δ extended the survival of mice infected with C. gattii strain R265 compared to unvaccinated groups, we were unable to demonstrate fungal clearance as robust as that seen following KN99 challenge. In stark contrast to vaccinated mice challenged with KN99, we also found that R265-challenged mice failed to induce the production of protection-associated cytokines and chemokines in the lungs. To investigate deficiencies in the vaccine response to R265 infection, we developed a KN99-R265 coinfection model. In unvaccinated mice, the strains behaved in a manner which mirrored single infections, wherein only KN99 disseminated to the brain and spleen. We expanded the coinfection model to Cn-cda1Δ2Δ3Δ-vaccinated mice. Fungal burden, cytokine production, and immune cell infiltration in the lungs of vaccinated, coinfected mice were indicative of immune evasion by C. gattii R265 as the presence of R265 neither compromised the immunophenotype established in response to KN99 nor inhibited clearance of KN99. Collectively, these data indicate that R265 does not dampen a protective vaccine response, but rather suggest that R265 remains largely undetected by the immune system.
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Affiliation(s)
- Maureen M. Hester
- Department of Medicine, The University of Massachusetts Chan Medical School, Worcester, MA, United States
| | - Diana Carlson
- Department of Medicine, The University of Massachusetts Chan Medical School, Worcester, MA, United States
| | - Jennifer K. Lodge
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC, United States
| | - Stuart M. Levitz
- Department of Medicine, The University of Massachusetts Chan Medical School, Worcester, MA, United States
| | - Charles A. Specht
- Department of Medicine, The University of Massachusetts Chan Medical School, Worcester, MA, United States
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Yoon H, Nakouzi AS, Duong VA, Hung LQ, Binh TQ, Tung NLN, Day JN, Pirofski LA. Shared and unique antibody and B cell profiles in HIV-positive and HIV-negative individuals with cryptococcal meningoencephalitis. Med Mycol 2023; 61:myad102. [PMID: 37771088 PMCID: PMC10599321 DOI: 10.1093/mmy/myad102] [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: 07/15/2023] [Revised: 09/07/2023] [Accepted: 09/27/2023] [Indexed: 09/30/2023] Open
Abstract
Host non-T cell markers to aid in the diagnosis of cryptococcal meningoencephalitis (CM) have not been identified. In this case-control study, we characterized antibody and B cell profiles in HIV-negative and HIV-positive Vietnamese individuals of the Kinh ethnicity recently diagnosed with CM and controls. The study included 60 HIV-negative with no known immunocompromising condition and 60 HIV-positive individuals, with 30 CM cases and 30 controls in each group. Participants were matched by age, sex, HIV serostatus, and CD4 count in the HIV-positive group. Plasma immunoglobulin (Ig) levels, including IgG1, IgG2, IgM, and IgA, Cryptococcus spp. glucuronoxylomannan (GXM)- and laminarin (branched ${\rm{\beta }}$-[1-3]-glucan)-binding IgG, IgM, IgA levels, and peripheral blood B cell subsets were measured. Logistic regression, principal component, and mediation analyses were conducted to assess associations between antibody, B cell levels, and CM. The results showed that GXM-IgG levels were higher and IgG1 and IgG2 were lower in CM cases than controls, regardless of HIV status. In HIV-negative individuals, IgG2 mediated an inverse association between CD19+CD27+CD43+CD5- (B-1b-like) cells and CM. In HIV-positive individuals, lower levels of IgA, laminarin-IgA, and CD19+CD27+IgM+IgD- (IgM+ memory B) cells were each associated with CM. The shared and distinct antibody and B cell profiles identified in HIV-negative and HIV-positive CM cases may inform the identification of non-T-cell markers of CM risk or unsuspected disease, particularly in HIV-negative individuals.
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Affiliation(s)
- Hyunah Yoon
- Division of Infectious Diseases, Department of Medicine, Albert Einstein College of Medicine, Montefiore Medical Center, Bronx, New York 10461, USA
| | - Antonio S Nakouzi
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Montefiore Medical Center, Bronx, New York 10461, USA
| | - Van Anh Duong
- Oxford University Clinical Research Unit, 764 Vo Van Kiet, Ho Chi Minh City Q5, Vietnam
| | - Le Quoc Hung
- Department of Tropical Diseases, Cho Ray Hospital, Ho Chi Minh City, Vietnam
| | - Tran Quang Binh
- Department of Tropical Diseases, Cho Ray Hospital, Ho Chi Minh City, Vietnam
| | - Nguyen Le Nhu Tung
- Hospital for Tropical Diseases, 764 Vo Van Kiet, Ho Chi Minh City Q5, Vietnam
| | - Jeremy N Day
- Oxford University Clinical Research Unit, 764 Vo Van Kiet, Ho Chi Minh City Q5, Vietnam
- Department of Microbiology and Infection, Royal Devon and Exeter Hospital, Exeter EX2 5DW, UK
| | - Liise-anne Pirofski
- Division of Infectious Diseases, Department of Medicine, Albert Einstein College of Medicine, Montefiore Medical Center, Bronx, New York 10461, USA
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Montefiore Medical Center, Bronx, New York 10461, USA
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Chen J, Shao J, Dai M, Fang W, Yang YL. Adaptive immunology of Cryptococcus neoformans infections-an update. Front Immunol 2023; 14:1174967. [PMID: 37251371 PMCID: PMC10213923 DOI: 10.3389/fimmu.2023.1174967] [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: 02/27/2023] [Accepted: 04/18/2023] [Indexed: 05/31/2023] Open
Abstract
The fungal genus Cryptococcus comprises a group of pathogens with considerable phenotypic and genotypic diversity that can lead to cryptococcosis in both healthy and immunocompromised individuals. With the emergence of the HIV pandemic, cryptococcosis, mainly meningoencephalitis, afflicts HIV-infected patients with severe dysfunction of T cells. It has also been reported in recipients of solid organ transplantation and in patients with autoimmune diseases who take immunosuppressive agents long-term, as well as in those with unidentified immunodeficiency. The clinical outcome of the disease is primarily determined by the immune response resulting from the interplay between the host immune system and the pathogen. Most human infections are caused by Cryptococcus neoformans, and nearly all immunological studies have focused on C. neoformans. This review provides an updated understanding of the role of adaptive immunity during infection with C. neoformans in human and animal models over the past half-decade.
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Affiliation(s)
- Junsong Chen
- Key Laboratory of Systems Biomedicine (Ministry of Education), Shanghai Center for Systems Biomedicine, Shanghai Jiao Tong University, Shanghai, China
| | - Jiasheng Shao
- Department of Immunology and Rheumatology, Jiading District Central Hospital Affiliated Shanghai University of Medicine & Health Science, Shanghai, China
- Tulane National Primate Research Center, Tulane University School of Medicine, Covington, LA, United States
| | - Min Dai
- Department of Immunology and Rheumatology, Jiading District Central Hospital Affiliated Shanghai University of Medicine & Health Science, Shanghai, China
| | - Wei Fang
- Department of Laser and Aesthetic Medicine, Shanghai Ninth People’s Hospital, Shanghai JiaoTong University School of Medicine, Shanghai, China
| | - Ya-li Yang
- Department of Laser and Aesthetic Medicine, Shanghai Ninth People’s Hospital, Shanghai JiaoTong University School of Medicine, Shanghai, China
- Department of Dermatology, Shanghai Ninth People’s Hospital, Shanghai JiaoTong University School of Medicine, Shanghai, China
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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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Immunological correlates of protection following vaccination with glucan particles containing Cryptococcus neoformans chitin deacetylases. NPJ Vaccines 2023; 8:6. [PMID: 36732332 PMCID: PMC9892683 DOI: 10.1038/s41541-023-00606-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Accepted: 01/23/2023] [Indexed: 02/04/2023] Open
Abstract
Vaccination with glucan particles (GP) containing the Cryptococcus neoformans chitin deacetylases Cda1 and Cda2 protect mice against experimental cryptococcosis. Here, immunological correlates of vaccine-mediated protection were explored. Studies comparing knockout and wild-type mice demonstrated CD4+ T cells are crucial, while B cells and CD8+ T cells are dispensable. Protection was abolished following CD4+ T cell depletion during either vaccination or infection but was retained if CD4+ T cells were only partially depleted. Vaccination elicited systemic and durable antigen-specific immune responses in peripheral blood mononuclear cells (PBMCs), spleens, and lungs. Following vaccination and fungal challenge, robust T-helper (Th) 1 and Th17 responses were observed in the lungs. Protection was abrogated in mice congenitally deficient in interferon (IFN) γ, IFNγ receptor, interleukin (IL)-1β, IL-6, or IL-23. Thus, CD4+ T cells and specific proinflammatory cytokines are required for GP-vaccine-mediated protection. Importantly, retention of protection in the setting of partial CD4+ T depletion suggests a pathway for vaccinating at-risk immunocompromised individuals.
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Dangarembizi R, Wasserman S, Hoving JC. Emerging and re-emerging fungal threats in Africa. Parasite Immunol 2023; 45:e12953. [PMID: 36175380 PMCID: PMC9892204 DOI: 10.1111/pim.12953] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Revised: 09/22/2022] [Accepted: 09/26/2022] [Indexed: 02/04/2023]
Abstract
The emergence of deadly fungal infections in Africa is primarily driven by a disproportionately high burden of human immunodeficiency virus (HIV) infections, lack of access to quality health care, and the unavailability of effective antifungal drugs. Immunocompromised people in Africa are therefore at high risk of infection from opportunistic fungal pathogens such as Cryptococcus neoformans and Pneumocystis jirovecii, which are associated with high morbidity, mortality, and related socioeconomic impacts. Other emerging fungal threats include Emergomyces spp., Histoplasma spp., Blastomyces spp., and healthcare-associated multi-drug resistant Candida auris. Socioeconomic development and the Covid-19 pandemic may influence shifts in epidemiology of invasive fungal diseases on the continent. This review discusses the epidemiology, clinical manifestations, and current management strategies available for these emerging fungal diseases in Africa. We also discuss gaps in knowledge, policy, and research to inform future efforts at managing these fungal threats.
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Affiliation(s)
- Rachael Dangarembizi
- Division of Physiological Sciences, Department of Human Biology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa,Neuroscience Institute, Faculty of Health Sciences, University of Cape Town, Groote Schuur Hospital, Cape Town, South Africa,CMM AFRICA Medical Mycology Research Unit, Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa,Contact information of corresponding author Dr Rachael Dangarembizi, Division of Physiological Sciences, Department of Human Biology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa, Neuroscience Institute, Faculty of Health Sciences, University of Cape Town, Groote Schuur Hospital, Cape Town, South Africa, CMM AFRICA Medical Mycology Research Unit, Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa,
| | - Sean Wasserman
- Wellcome Centre for Infectious Diseases Research in Africa, Institute of Infectious Diseases and Molecular Medicine, University of Cape Town, Cape Town, South Africa,Division of Infectious Diseases and HIV Medicine, Department of Medicine, University of Cape Town, Groote Schuur Hospital, Cape Town, South Africa
| | - Jennifer Claire Hoving
- Division of Immunology, Department of Pathology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa,Wellcome Centre for Infectious Diseases Research in Africa, Institute of Infectious Diseases and Molecular Medicine, University of Cape Town, Cape Town, South Africa,CMM AFRICA Medical Mycology Research Unit, Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
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Muacevic A, Adler JR. Cryptococcal Neoformans and Varicella Zoster Meningitis in a Patient With Selective Innate Immunodeficiency: A Case Report. Cureus 2023; 15:e33490. [PMID: 36756011 PMCID: PMC9902066 DOI: 10.7759/cureus.33490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/04/2023] [Indexed: 01/09/2023] Open
Abstract
Cryptococcal neoformans (C. neoformans) and varicella-zoster (VZV) meningitis are opportunistic infections that are primarily seen in immunocompromised patients, including those with HIV, cancer, or receiving transplants. Despite treatment, infection in immunocompromised patients can be lethal, including those with T-cell dysfunction or deficiency. Whether innate immunodeficiencies also predispose to these infections remains less clear. Here, we report a case of disseminated C. neoformans and VZV meningitis in a young male with idiopathic hypereosinophilic syndrome and hypocomplementemia and no history of HIV infection, malignancy, or transplant. The patient presented with a pulsating headache, myalgia, joint pain, insomnia, night sweats, and subjective fever, along with clusters of vesicular lesions on his neck and back. A lumbar puncture and an MRI of the brain confirmed C. neoformans and VZV meningitis. Vesicular skin lesions proved to be VZV, and blood culture confirmed fungemia, suggesting disseminated disease. We investigated his medical history further to determine the underlying cause of his prior hypereosinophilia and current meningitis. The patient had idiopathic hypereosinophilia with high IgE levels, low complement levels, high rheumatoid factor levels, and an intermittent rash dating back two years, which had been treated intermittently with prednisone and hydroxyurea, with the most recent admission three weeks prior to this admission. Prior to admission, the patient had a peak absolute eosinophil count of 18.6 x103/uL. The patient was discharged on a daily dose of 60 mg of prednisone without hydroxyurea. In further evaluating his immune status, we found he was HIV-negative, with a normal CD4 count and high IgE. We also tested lymphocyte subsets and proliferation, which showed a low CD16/56 level, suggesting possibly reduced natural killer (NK) cell quantity. The patient responded well to acyclovir, amphotericin, and flucytosine therapy. After follow-up cerebrospinal fluid (CSF) and blood cultures were negative, the patient was discharged with fluconazole as maintenance therapy.
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Nelson BN, Daugherty CS, Sharp RR, Booth JL, Patel VI, Metcalf JP, Jones KL, Wozniak KL. Protective interaction of human phagocytic APC subsets with Cryptococcus neoformans induces genes associated with metabolism and antigen presentation. Front Immunol 2022; 13:1054477. [PMID: 36466930 PMCID: PMC9709479 DOI: 10.3389/fimmu.2022.1054477] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Accepted: 10/25/2022] [Indexed: 09/01/2023] Open
Abstract
Cryptococcal meningitis is the most common cause of meningitis among HIV/AIDS patients in sub-Saharan Africa, and worldwide causes over 223,000 cases leading to more than 181,000 annual deaths. Usually, the fungus gets inhaled into the lungs where the initial interactions occur with pulmonary phagocytes such as dendritic cells and macrophages. Following phagocytosis, the pathogen can be killed or can replicate intracellularly. Previous studies in mice showed that different subsets of these innate immune cells can either be antifungal or permissive for intracellular fungal growth. Our studies tested phagocytic antigen-presenting cell (APC) subsets from the human lung against C. neoformans. Human bronchoalveolar lavage was processed for phagocytic APCs and incubated with C. neoformans for two hours to analyze the initial interactions and fate of the fungus, living or killed. Results showed all subsets (3 macrophage and 3 dendritic cell subsets) interacted with the fungus, and both living and killed morphologies were discernable within the subsets using imaging flow cytometry. Single cell RNA-seq identified several different clusters of cells which more closely related to interactions with C. neoformans and its protective capacity against the pathogen rather than discrete cellular subsets. Differential gene expression analyses identified several changes in the innate immune cell's transcriptome as it kills the fungus including increases of TNF-α (TNF) and the switch to using fatty acid metabolism by upregulation of the gene FABP4. Also, increases of TNF-α correlated to cryptococcal interactions and uptake. Together, these analyses implicated signaling networks that regulate expression of many different genes - both metabolic and immune - as certain clusters of cells mount a protective response and kill the pathogen. Future studies will examine these genes and networks to understand the exact mechanism(s) these phagocytic APC subsets use to kill C. neoformans in order to develop immunotherapeutic strategies to combat this deadly disease.
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Affiliation(s)
- Benjamin N. Nelson
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, United States
| | - Cheyenne S. Daugherty
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, United States
| | - Rachel R. Sharp
- Harold Hamm Diabetes Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
| | - J. Leland Booth
- Department of Medicine, Pulmonary, Critical Care & Sleep Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
| | - Vineet I. Patel
- Department of Medicine, Pulmonary, Critical Care & Sleep Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
| | - Jordan P. Metcalf
- Department of Medicine, Pulmonary, Critical Care & Sleep Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
- Veterans Affairs Medical Center, Oklahoma City, OK, United States
| | - Kenneth L. Jones
- Harold Hamm Diabetes Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
| | - Karen L. Wozniak
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, United States
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13
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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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Hester MM, Oliveira LVN, Wang R, Mou Z, Lourenco D, Ostroff GR, Specht CA, Levitz SM. Cross-reactivity between vaccine antigens from the chitin deacetylase protein family improves survival in a mouse model of cryptococcosis. Front Immunol 2022; 13:1015586. [PMID: 36248898 PMCID: PMC9554598 DOI: 10.3389/fimmu.2022.1015586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 08/31/2022] [Indexed: 12/15/2022] Open
Abstract
Meningitis due to the fungal pathogen Cryptococcus neoformans is estimated to cause nearly 200,000 deaths annually, mostly in resource-limited regions. We previously identified cryptococcal protein antigens which, when delivered in glucan particles, afford vaccine-mediated protection against an otherwise lethal infection. Many of these proteins exhibit significant homology to other similar cryptococcal proteins leading us to hypothesize that protection may be augmented by immunologic cross-reactivity to multiple members of a protein family. To examine the significance of protein cross-reactivity in vaccination, we utilized strains of Cryptococcus that are genetically deficient in select antigens, yet are still lethal in mice. Vaccination with a protein without homologs (e.g., Mep1 and Lhc1) protected against challenge with wild-type Cryptococcus, but not against a deletion strain lacking that protein. Contrastingly, vaccination with a single chitin deacetylase (Cda) protein protected against the corresponding deletion strain, presumably due to host recognition of one or more other family members still expressed in this strain. Vaccination with a single Cda protein induced cross-reactive antibody and interferon-gamma (IFNγ) immune responses to other Cda protein family members. Paradoxically, we saw no evidence of cross-protection within the carboxypeptidase family of proteins. Factors such as in vivo protein expression and the degree of homology across the family could inform the extent to which vaccine-mediated immunity is amplified. Together, these data suggest a role for prioritizing protein families in fungal vaccine design: increasing the number of immune targets generated by a single antigen may improve efficacy while diminishing the risk of vaccine-resistant strains arising from gene mutations.
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Affiliation(s)
- Maureen M. Hester
- Department of Medicine, The University of Massachusetts Chan Medical School, Worcester, MA, United States
| | - Lorena V. N. Oliveira
- Department of Medicine, The University of Massachusetts Chan Medical School, Worcester, MA, United States
| | - Ruiying Wang
- Department of Medicine, The University of Massachusetts Chan Medical School, Worcester, MA, United States
| | - Zhongming Mou
- Department of Medicine, The University of Massachusetts Chan Medical School, Worcester, MA, United States
| | - Diana Lourenco
- Department of Medicine, The University of Massachusetts Chan Medical School, Worcester, MA, United States
| | - Gary R. Ostroff
- Program in Molecular Medicine, The University of Massachusetts Chan Medical School, Worcester, MA, United States
| | - Charles A. Specht
- Department of Medicine, The University of Massachusetts Chan Medical School, Worcester, MA, United States
| | - Stuart M. Levitz
- Department of Medicine, The University of Massachusetts Chan Medical School, Worcester, MA, United States
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15
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Ma H, Wang X, Yan H, Liu Q, Yang D, Bian T. Dual intracranial infection with Nocardia farcinica and Cryptococcus neoformans diagnosed by next-generation sequencing in a patient with nephrotic syndrome: A case report. Medicine (Baltimore) 2022; 101:e30325. [PMID: 36107518 PMCID: PMC9439795 DOI: 10.1097/md.0000000000030325] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
RATIONALE Intracranial infections are associated with high morbidity and mortality in immunocompromised patients, due to delayed diagnosis and treatment. Establishing a rapid, accurate diagnosis and a precise therapeutic regimen is crucial for management of the patients. Our report described a rare intracranial infection of patient with nephrotic syndrome. PATIENT CONCERNS A 66-year-old woman with a history of nephrotic syndrome presented symptoms in central nervous system for 1 month, followed by headache and fever over several days. DIAGNOSIS Neurological examination, brain imaging, and cerebrospinal fluid (CSF) tests exhibited resemblance to intracranial infection. Subsequently, CSF cultures confirmed the presence of Cryptococcus. Fortunately, next-generation sequencing revealed the concomitant infection with Nocardia farcinica in addition to Cryptococcus neoformans. INTERVENTIONS The treatment with intravenous fluconazole combined with amphotericin could not immediately ameliorate her symptoms. The patient's condition improved significantly with minimal deficits after timely administration of antibiotics against N farcinica. OUTCOMES One month later, cranial MRI indicated that basal ganglia lesions ameliorated. The patient has recovered well. LESSONS SUBSECTIONS To our best knowledge, this is the first case report of intracranial infection caused by both N farcinica and C neoformans in a patient with nephrotic syndrome. Remarkably, extensive application of next-generation sequencing can facilitate investigation on the potential role of various pathogenic organisms in infectious diseases.
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Affiliation(s)
- Hongmei Ma
- Department of Neurology, Beijing Fengtai You’anmen Hospital, BeijingChina
- *Correspondence: Hongmei Ma, Department of Neurology, Beijing Fengtai You’anmen Hospital, No. 199 You’anmen Wai Avenue, Fengtai District, Beijing 100069, China (e-mail: )
| | - Xiangbo Wang
- Department of Neurology, Xuanwu Hospital of Capital Medical University, Beijing, China
| | - Heli Yan
- Department of Neurology, Xuanwu Hospital of Capital Medical University, Beijing, China
| | - Qing Liu
- Department of Neurology, Beijing Fengtai You’anmen Hospital, BeijingChina
| | - Dan Yang
- Department of Neurology, Beijing Fengtai You’anmen Hospital, BeijingChina
| | - Tingting Bian
- Department of Neurology, Beijing Fengtai You’anmen Hospital, BeijingChina
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IL-9 plays a protective role on host defense against the infection of Cryptococcus Neoformans. J Mycol Med 2022; 32:101297. [PMID: 35660540 DOI: 10.1016/j.mycmed.2022.101297] [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: 12/19/2021] [Revised: 05/17/2022] [Accepted: 05/19/2022] [Indexed: 11/21/2022]
Abstract
Cryptococcus neoformans is an opportunistic fungal pathogen that causes neurological disease in immunocompromised patients. Preliminary experiments showed that cryptococcal strains could induce the expression of interleukin-9 (IL-9). The use of a neutralizing antibody against IL-9 decreased the survival rates of mice in a murine model. In this study, we found that in vitro, IL-9 could enhance the phagocytic function of M1 macrophages and promote the killing of extracellular pathogens by had no effect on the killing of invading pathogens. IL-9 could also promote the expression of IL-6 while suppressing the expression of TNF-α in M1 macrophages. In vivo, IL-9 reduced the colony-forming units (CFUs) in the brain and liver, but there were no differences in the lung. Furthermore, the weight of mice in the IL-9 group decreased slower than that of mice in the phosphate-buffered saline (PBS) group after infection. Moreover, IL-9 could enhance the survival rate at 21 days. The results also showed that IL-9 could promote the secretion of IL-17 while blocking the secretion of IL-4. Therefore, we concluded that IL-9 plays a protective role in C. neoformans infection.
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17
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Rathore SS, Sathiyamoorthy J, Lalitha C, Ramakrishnan J. A holistic review on Cryptococcus neoformans. Microb Pathog 2022; 166:105521. [DOI: 10.1016/j.micpath.2022.105521] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 04/06/2022] [Accepted: 04/06/2022] [Indexed: 12/21/2022]
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18
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Berguson HP, Caulfield LW, Price MS. Influence of Pathogen Carbon Metabolism on Interactions With Host Immunity. Front Cell Infect Microbiol 2022; 12:861405. [PMID: 35372116 PMCID: PMC8968422 DOI: 10.3389/fcimb.2022.861405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 02/24/2022] [Indexed: 11/22/2022] Open
Abstract
Cryptococcus neoformans is a ubiquitous opportunistic fungal pathogen typically causing disease in immunocompromised individuals and is globally responsible for about 15% of AIDS-related deaths annually. C. neoformans first causes pulmonary infection in the host and then disseminates to the brain, causing meningoencephalitis. The yeast must obtain and metabolize carbon within the host in order to survive in the central nervous system and cause disease. Communication between pathogen and host involves recognition of multiple carbon-containing compounds on the yeast surface: polysaccharide capsule, fungal cell wall, and glycosylated proteins comprising the major immune modulators. The structure and function of polysaccharide capsule has been studied for the past 70 years, emphasizing its role in virulence. While protected by the capsule, fungal cell wall has likewise been a focus of study for several decades for its role in cell integrity and host recognition. Associated with both of these major structures are glycosylated proteins, which exhibit known immunomodulatory effects. While many studies have investigated the role of carbon metabolism on virulence and survival within the host, the precise mechanism(s) affecting host-pathogen communication remain ill-defined. This review summarizes the current knowledge on mutants in carbon metabolism and their effect on the host immune response that leads to changes in pathogen recognition and virulence. Understanding these critical interactions will provide fresh perspectives on potential treatments and the natural history of cryptococcal disease.
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Affiliation(s)
- Hannah P. Berguson
- Department of Anatomical Sciences, Liberty University College of Osteopathic Medicine, Lynchburg, VA, United States
| | - Lauren W. Caulfield
- Department of Biology and Chemistry, Liberty University, Lynchburg, VA, United States
| | - Michael S. Price
- Department of Molecular and Cellular Sciences, Liberty University College of Osteopathic Medicine, Lynchburg, VA, United States
- Department of Medicine, Duke University School of Medicine, Durham, NC, United States
- *Correspondence: Michael S. Price,
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19
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Central Nervous System Fungal Infections in Paediatric Patients. CURRENT FUNGAL INFECTION REPORTS 2022. [DOI: 10.1007/s12281-021-00427-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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20
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Dangarembizi R. Reimagining the future of African brain health: Perspectives for basic research on the pathogenesis of cryptococcal meningitis. Brain Behav Immun Health 2021; 18:100388. [PMID: 34825235 PMCID: PMC8605210 DOI: 10.1016/j.bbih.2021.100388] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2021] [Revised: 10/28/2021] [Accepted: 11/05/2021] [Indexed: 11/24/2022] Open
Abstract
Cryptococcal meningitis is a fatal opportunistic infection of the brain and a leading cause of neurological damage and death in immunocompromised individuals. This neglected fungal disease of the brain is a huge burden on the health systems of developing countries, especially in Sub-Saharan Africa, where up to 25% of people living with HIV/AIDS succumb to it. Cryptococcal fungal cells have a predilection for the brain and they are capable of traversing the blood brain barrier and invade the brain where they cause infection, inflammation and a disruption of normal brain function. A robust host neuroimmune response is critical for pathogen clearance and survival, and a good understanding of the mechanisms underlying its development in the host is critical for the development of effective treatments. However, past basic research studies have been focussed on the characteristics of the fungus and its effect on the peripheral immune system; with little attention paid to how it interacts with brain immune cells. This mini review briefly discusses the paucity of basic research data on the neuroimmune response to cryptococcal infection, raises pertinent questions on how the brain cells respond to the fungal infection, and thereafter discusses models, techniques and advanced technologies that could be useful for carrying out high-throughput research on the pathogenesis of cryptococcal meningitis.
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Affiliation(s)
- R Dangarembizi
- Division of Physiological Sciences, Department of Human Biology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
- Neuroscience Institute, Faculty of Health Sciences, University of Cape Town, Groote Schuur Hospital, Cape Town, South Africa
- CMM AFRICA Medical Mycology Research Unit, Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
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21
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Wang Y, Gu Y, Shen K, Cui X, Min R, Sun S, Feng C, Chen Y, Wang L, Cao M, Yang J, Yao J, Xu J, Lin D, Tao Y, Ma G, Shi J, Chen B, Ni Y, Zhong H, Shi Y, Su X. Clinical features of cryptococcosis in patients with different immune statuses: a multicenter study in Jiangsu Province-China. BMC Infect Dis 2021; 21:1043. [PMID: 34625036 PMCID: PMC8499499 DOI: 10.1186/s12879-021-06752-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2021] [Accepted: 09/29/2021] [Indexed: 12/25/2022] Open
Abstract
Background Current guidelines support different management of cryptococcosis between severely immunodeficient and immunocompetent populations. However, few studies have focused on cryptococcosis patients with mild-to-moderate immunodeficiency. We performed this study to determine the clinical features of pulmonary (PC) and extrapulmonary cryptococcosis (EPC) and compared them among populations with different immune statuses to support appropriate clinical management of this public health threat. Methods All cases were reported by 14 tertiary teaching hospitals in Jiangsu Province, China from January 2013 to December 2018. The trends in incidence, demographic data, medical history, clinical symptoms, laboratory test indicators, imaging characteristics and diagnostic method of these patients were then stratified by immune status, namely immunocompetent (IC, patients with no recognized underlying disease or those with an underlying disease that does not influence immunity, such as hypertension), mild-to-moderate immunodeficiency (MID, patients with diabetes mellitus, end-stage liver or kidney disease, autoimmune diseases treated with low-dose glucocorticoid therapy, and cancer treated with chemotherapy) and severe immunodeficiency (SID, patients with acquired immunodeficiency syndrome, haematologic malignancies, solid organ transplantation or haematologic stem cell transplantation, idiopathic CD4 lymphocytosis, agranulocytosis, aggressive glucocorticoid or immunosuppressive therapy and other conditions or treatments that result in severe immunosuppression). Results The clinical data of 255 cryptococcosis patients were collected. In total, 66.3% of patients (169) were IC, 16.9% (43) had MID, and 16.9% (43) had SID. 10.1% of the patients (17) with IC were EPC, 18.6% of the patients (8) with MID were EPC, and 74.4% of patients (32) were EPC (IC/MID vs. SID, p < 0.001). Fever was more common in the SID group than in the IC and MID groups (69.8% vs. 14.8% vs. 37.2%, p < 0.001). Of chest CT scan, most lesions were distributed under the pleura (72.7%), presenting as nodules/lumps (90.3%) or consolidations (10.7%). Pleural effusion was more common in SID group compared to IC group (33.3% vs. 2.4%, p < 0.001). Positivity rate on the serum capsular polysaccharide antigen detection (CrAg) test was higher in the SID group than in the other two groups [100.0% vs. 84.4% (MID) vs. 78.2% (IC), p = 0.013]. Positivity rate on the serum CrAg test was also higher in cryptococcal meningitis patients than in PC patients (100.0% vs. 79.5%, p = 0.015). Conclusions The clinical presentation of MID patients is intermediate between SID and IC patients and is similar to that of IC patients. The serum CrAg test is more sensitive for the identification of SID or EPC patients.
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Affiliation(s)
- Yu Wang
- Department of Respiratory and Critical Care Medicine, Jinling Hospital, Medical School of Nanjing University, Nanjing, 210002, China
| | - Yu Gu
- Department of Respiratory and Critical Care Medicine, Jinling Hospital, Nanjing Medical University, Nanjing, 210002, China
| | - Kunlu Shen
- Department of Respiratory and Critical Care Medicine, Jinling Hospital, Southern Medical University, Guangzhou, 510000, China
| | - Xuefan Cui
- Department of Respiratory and Critical Care Medicine, Jiangsu Province Hospital, Nanjing Medical University, Nanjing, 210002, China
| | - Rui Min
- Department of Respiratory and Critical Care Medicine, Jiangsu Province Hospital, Nanjing Medical University, Nanjing, 210002, China
| | - Siqing Sun
- Department of Respiratory and Critical Care Medicine, The Second Hospital of Nanjing, Nanjing, 210002, China
| | - Chunlai Feng
- Department of Respiratory and Critical Care Medicine, The Third Affiliated Hospital of Soochow University, Changzhou, 213000, China
| | - Yanbin Chen
- Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital of Soochow University, Suzhou, 215000, China
| | - Li Wang
- Department of Respiratory and Critical Care Medicine, Nanjing First Hospital, Nanjing Medical University, Nanjing, 210002, China
| | - Min Cao
- Department of Respiratory and Critical Care Medicine, Nanjing Drum Tower Hospital, Medical School of Nanjing University, Nanjing, 210002, China
| | - Jian Yang
- Department of Respiratory and Critical Care Medicine, The Affiliated Jiangning Hospital of Nanjing Medical University, Nanjing, 210002, China
| | - Jian Yao
- Department of Respiratory and Critical Care Medicine, The First People's Hospital of Nantong, Nantong, 226000, China
| | - Jing Xu
- Department of Respiratory and Critical Care Medicine, Jiangsu Province Hospital of Chinese Medicine, Nanjing, 210002, China
| | - Dang Lin
- Department of Respiratory and Critical Care Medicine, Suzhou Municipal Hospital, Suzhou, 215000, China
| | - Yujian Tao
- Department of Respiratory and Critical Care Medicine, Affiliated Hospital of Yangzhou University, Yangzhou, 225000, China
| | - Guoer Ma
- Department of Respiratory and Critical Care Medicine, Affiliated Hospital of Jiangsu University, Zhenjiang, 212000, China
| | - Jiaxin Shi
- Department of Respiratory and Critical Care Medicine, The First People's Hospital of Lianyungang, Lianyungang, 222000, China
| | - Bilin Chen
- Department of Respiratory and Critical Care Medicine, Jinling Hospital, Medical School of Nanjing University, Nanjing, 210002, China
| | - Yueyan Ni
- Department of Respiratory and Critical Care Medicine, Jinling Hospital, Nanjing Medical University, Nanjing, 210002, China
| | - Huanhuan Zhong
- Department of Respiratory and Critical Care Medicine, Jinling Hospital, Medical School of Nanjing University, Nanjing, 210002, China
| | - Yi Shi
- Department of Respiratory and Critical Care Medicine, Jinling Hospital, Medical School of Nanjing University, Nanjing, 210002, China
| | - Xin Su
- Department of Respiratory and Critical Care Medicine, Jinling Hospital, Medical School of Nanjing University, Nanjing, 210002, China. .,Department of Respiratory and Critical Care Medicine, Jinling Hospital, Nanjing Medical University, Nanjing, 210002, China. .,Department of Respiratory and Critical Care Medicine, Jinling Hospital, Southern Medical University, Guangzhou, 510000, China.
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22
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Gressler AE, Volke D, Firacative C, Schnabel CL, Müller U, Krizsan A, Schulze-Richter B, Brock M, Brombacher F, Escandón P, Hoffmann R, Alber G. Identification of Disease-Associated Cryptococcal Proteins Reactive With Serum IgG From Cryptococcal Meningitis Patients. Front Immunol 2021; 12:709695. [PMID: 34367172 PMCID: PMC8342929 DOI: 10.3389/fimmu.2021.709695] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Accepted: 06/21/2021] [Indexed: 01/16/2023] Open
Abstract
Cryptococcus neoformans, an opportunistic fungal pathogen ubiquitously present in the environment, causes cryptococcal meningitis (CM) mainly in immunocompromised patients, such as AIDS patients. We aimed to identify disease-associated cryptococcal protein antigens targeted by the human humoral immune response. Therefore, we used sera from Colombian CM patients, with or without HIV infection, and from healthy individuals living in the same region. Serological analysis revealed increased titers of anti-cryptococcal IgG in HIV-negative CM patients, but not HIV-positive CM patients, compared to healthy controls. In contrast, titers of anti-cryptococcal IgM were not affected by CM. Furthermore, we detected pre-existing IgG and IgM antibodies even in sera from healthy individuals. The observed induction of anti-cryptococcal IgG but not IgM during CM was supported by analysis of sera from C. neoformans-infected mice. Stronger increase in IgG was found in wild type mice with high lung fungal burden compared to IL-4Rα-deficient mice showing low lung fungal burden. To identify the proteins targeted by human anti-cryptococcal IgG antibodies, we applied a quantitative 2D immunoproteome approach identifying cryptococcal protein spots preferentially recognized by sera from CM patients or healthy individuals followed by mass spectrometry analysis. Twenty-three cryptococcal proteins were recombinantly expressed and confirmed to be immunoreactive with human sera. Fourteen of them were newly described as immunoreactive proteins. Twelve proteins were classified as disease-associated antigens, based on significantly stronger immunoreactivity with sera from CM patients compared to healthy individuals. The proteins identified in our screen significantly expand the pool of cryptococcal proteins with potential for (i) development of novel anti-cryptococcal agents based on implications in cryptococcal virulence or survival, or (ii) development of an anti-cryptococcal vaccine, as several candidates lack homology to human proteins and are localized extracellularly. Furthermore, this study defines pre-existing anti-cryptococcal immunoreactivity in healthy individuals at a molecular level, identifying target antigens recognized by sera from healthy control persons.
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Affiliation(s)
- A Elisabeth Gressler
- Institute of Immunology, Faculty of Veterinary Medicine, Leipzig University, Leipzig, Germany
| | - Daniela Volke
- Institute of Bioanalytical Chemistry, Leipzig University, Leipzig, Germany
| | - Carolina Firacative
- Studies in Translational Microbiology and Emerging Diseases (MICROS) Research Group, School of Medicine and Health Sciences, Universidad del Rosario, Bogota, Colombia
| | - Christiane L Schnabel
- Institute of Immunology, Faculty of Veterinary Medicine, Leipzig University, Leipzig, Germany
| | - Uwe Müller
- Institute of Immunology, Faculty of Veterinary Medicine, Leipzig University, Leipzig, Germany
| | - Andor Krizsan
- Institute of Bioanalytical Chemistry, Leipzig University, Leipzig, Germany
| | - Bianca Schulze-Richter
- Institute of Immunology, Faculty of Veterinary Medicine, Leipzig University, Leipzig, Germany
| | - Matthias Brock
- Fungal Genetics and Biology Group, School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Frank Brombacher
- International Centre for Genetic Engineering and Biotechnology (ICGEB), Cape Town Component, Cape Town, South Africa
| | | | - Ralf Hoffmann
- Institute of Bioanalytical Chemistry, Leipzig University, Leipzig, Germany
| | - Gottfried Alber
- Institute of Immunology, Faculty of Veterinary Medicine, Leipzig University, Leipzig, Germany
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23
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Antifungal activity of dendritic cell lysosomal proteins against Cryptococcus neoformans. Sci Rep 2021; 11:13619. [PMID: 34193926 PMCID: PMC8245489 DOI: 10.1038/s41598-021-92991-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Accepted: 06/14/2021] [Indexed: 12/17/2022] Open
Abstract
Cryptococcal meningitis is a life-threatening disease among immune compromised individuals that is caused by the opportunistic fungal pathogen Cryptococcus neoformans. Previous studies have shown that the fungus is phagocytosed by dendritic cells (DCs) and trafficked to the lysosome where it is killed by both oxidative and non-oxidative mechanisms. While certain molecules from the lysosome are known to kill or inhibit the growth of C. neoformans, the lysosome is an organelle containing many different proteins and enzymes that are designed to degrade phagocytosed material. We hypothesized that multiple lysosomal components, including cysteine proteases and antimicrobial peptides, could inhibit the growth of C. neoformans. Our study identified the contents of the DC lysosome and examined the anti-cryptococcal properties of different proteins found within the lysosome. Results showed several DC lysosomal proteins affected the growth of C. neoformans in vitro. The proteins that killed or inhibited the fungus did so in a dose-dependent manner. Furthermore, the concentration of protein needed for cryptococcal inhibition was found to be non-cytotoxic to mammalian cells. These data show that many DC lysosomal proteins have antifungal activity and have potential as immune-based therapeutics.
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24
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Liu M, Sun LY, Zhu ZJ, Wei L, Qu W, Zeng ZG, Liu Y. Successful Treatment of Pulmonary Cryptococcosis in a Liver Transplant Recipient Before and After Liver Transplant: Case Report and Literature Review. EXP CLIN TRANSPLANT 2021; 19:264-268. [PMID: 33535937 DOI: 10.6002/ect.2020.0222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Cryptococcosis is the third most common invasive fungal infection in solid-organ transplant recipients. Patients with cirrhosis are susceptible to pretransplant cryptococcosis infections. Outcomes and optimal treatment of patients with cirrhosis who develop pulmonary cryptococcosis before and after liver transplant are still not defined. Here, we describe a case of cholestatic cirrhosis in a 50-year-old woman with a pretransplant asymptomatic pulmonary nodule. She had taken steroids for more than 1 year before she was admitted to our hospital. This asymptomatic case with a lung nodule was detected via an abnormal chest computed tomography. Cryptococcal pneumonia was diagnosed according to lung biopsy results. Testing for cryptococcal antigens was negative in the serum. The patient received antifungal therapy with amphotericin B followed by oral fluconazole, which was then followed by liver transplant. After antifungal therapy with fluconazole posttransplant, a sustained clinical response was achieved. After literature review of patients with pulmonary cryptococcosis before and after liver transplant, we identified previously reported cases with pulmonary cryptococcosis that resembled lung nodule on imaging. In this report, we aimed to raise the awareness of unrecognized pretransplant cryptococ-cosis infections in patients with cirrhosis who are waiting for liver transplant and showed the successful management of a patient with pretransplant pulmonary cryptococcosis.
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Affiliation(s)
- Min Liu
- From the National Clinical Research Center for Digestive Diseases, Beijing Friendship Hospital, Capital Medical University, Beijing, China
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25
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Normile TG, Bryan AM, Del Poeta M. Animal Models of Cryptococcus neoformans in Identifying Immune Parameters Associated With Primary Infection and Reactivation of Latent Infection. Front Immunol 2020; 11:581750. [PMID: 33042164 PMCID: PMC7522366 DOI: 10.3389/fimmu.2020.581750] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Accepted: 08/12/2020] [Indexed: 12/13/2022] Open
Abstract
Cryptococcus species are environmental fungal pathogens and the causative agents of cryptococcosis. Infection occurs upon inhalation of infectious particles, which proliferate in the lung causing a primary infection. From this primary lung infection, fungal cells can eventually disseminate to other organs, particularly the brain, causing lethal meningoencephalitis. However, in most cases, the primary infection resolves with the formation of a lung granuloma. Upon severe immunodeficiency, dormant cryptococcal cells will start proliferating in the lung granuloma and eventually will disseminate to the brain. Many investigators have sought to study the protective host immune response to this pathogen in search of host parameters that keep the proliferation of cryptococcal cells under control. The majority of the work assimilates research carried out using the primary infection animal model, mainly because a reactivation model has been available only very recently. This review will focus on anti-cryptococcal immunity in both the primary and reactivation models. An understanding of the differences in host immunity between the primary and reactivation models will help to define the key host parameters that control the infections and are important for the research and development of new therapeutic and vaccine strategies against cryptococcosis.
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Affiliation(s)
- Tyler G Normile
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, NY, United States
| | - Arielle M Bryan
- Ingenious Targeting Laboratory Incorporated, Ronkonkoma, NY, United States
| | - Maurizio Del Poeta
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, NY, United States.,Division of Infectious Diseases, School of Medicine, Stony Brook University, Stony Brook, NY, United States.,Veterans Administration Medical Center, Northport, NY, United States
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26
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Gupta S, Paul K, Kaur S. Diverse species in the genus Cryptococcus: Pathogens and their non-pathogenic ancestors. IUBMB Life 2020; 72:2303-2312. [PMID: 32897638 DOI: 10.1002/iub.2377] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 08/15/2020] [Accepted: 08/16/2020] [Indexed: 12/14/2022]
Abstract
The genus Cryptococcus comprises of more than 30 species. It consists of clinically significant pathogenic Cryptococcus neoformans/Cryptococcus gattii species complex comprising of a minimum of seven species. These pathogens cost more than 200,000 lives annually by causing cryptococcal meningoencephalitis. The evolution of the pathogenic species from closely related non-pathogenic species of the Cryptococcus amylolentus complex is of particular importance and several advances have been made to understand their phylogenetic and genomic relationships. The current review briefly describes the sexual reproduction process followed by an individual description of the members focusing on their key attributes and virulence mechanisms of the pathogenic species. A special section on phylogenetic studies is aimed at understanding the evolutionary divergence of pathogens from non-pathogens. Recent findings from our group pertaining to parameters affecting codon usage bias in six pathogenic and three non-pathogenic ancestral species and their corroboration with existing phylogenetic reports are also included in the current review.
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Affiliation(s)
- Shelly Gupta
- Department of Biochemistry, Lovely Professional University, Kapurthala, India
| | - Karan Paul
- Department of Biochemistry, DAV University, Jalandhar, India
| | - Sukhmanjot Kaur
- Department of Biochemistry, Lovely Professional University, Kapurthala, India
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27
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Okurut S, Boulware DR, Olobo J, Meya DB. Landmark clinical observations and immunopathogenesis pathways linked to HIV and Cryptococcus fatal central nervous system co-infection. Mycoses 2020; 63:840-853. [PMID: 32472727 PMCID: PMC7416908 DOI: 10.1111/myc.13122] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 05/21/2020] [Accepted: 05/22/2020] [Indexed: 12/13/2022]
Abstract
Cryptococcal meningitis remains one of the leading causes of death among HIV-infected adults in the fourth decade of HIV era in sub-Saharan Africa, contributing to 10%-20% of global HIV-related deaths. Despite widespread use and early induction of ART among HIV-infected adults, incidence of cryptococcosis remains significant in those with advanced HIV disease. Cryptococcus species that causes fatal infection follows systemic spread from initial environmental acquired infection in lungs to antigenaemia and fungaemia in circulation prior to establishment of often fatal disease, cryptococcal meningitis in the CNS. Cryptococcus person-to-person transmission is uncommon, and deaths related to blood infection without CNS involvement are rare. Keen to the persistent high mortality associated with HIV-cryptococcal meningitis, seizures are common among a third of the patients, altered mental status is frequent, anaemia is prevalent with ensuing brain hypoxia and at autopsy, brain fibrosis and infarction are evident. In addition, fungal burden is 3-to-4-fold higher in those with seizures. And high immune activation together with exacerbated inflammation and elevated PD-1/PD-L immune checkpoint expression is immunomodulated phenotypes elevated in CSF relative to blood. Lastly, though multiple Cryptococcus species cause disease in this setting, observations are mostly generalised to cryptococcal infection/meningitis or regional dominant species (C neoformans or gattii complex) that may limit our understanding of interspecies differences in infection, progression, treatment or recovery outcome. Together, these factors and underlying mechanisms are hypotheses generating for research to find targets to prevent infection or adequate therapy to prevent persistent high mortality with current optimal therapy.
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Affiliation(s)
- Samuel Okurut
- Research DepartmentInfectious Diseases InstituteMakerere UniversityKampalaUganda
- Department of MicrobiologySchool of Biomedical SciencesCollege of Health SciencesMakerere UniversityKampalaUganda
| | - David R. Boulware
- Division of Infectious Diseases and International MedicineDepartment of MedicineUniversity of MinnesotaMinneapolisMinnesota
| | - Joseph Olobo
- Department of Immunology and Molecular BiologySchool of Biomedical SciencesCollege of Health SciencesMakerere UniversityKampalaUganda
| | - David B. Meya
- Research DepartmentInfectious Diseases InstituteMakerere UniversityKampalaUganda
- Division of Infectious Diseases and International MedicineDepartment of MedicineUniversity of MinnesotaMinneapolisMinnesota
- Department of MedicineSchool of MedicineCollege of Health SciencesMakerere UniversityKampalaUganda
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28
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Clinical analysis in immunocompetent and immunocompromised patients with pulmonary cryptococcosis in western China. Sci Rep 2020; 10:9387. [PMID: 32523003 PMCID: PMC7287058 DOI: 10.1038/s41598-020-66094-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Accepted: 05/15/2020] [Indexed: 02/05/2023] Open
Abstract
Cryptococcosis is a systemic infection and it may occur in immunocompromised and immunocompetent hosts. In order to better understand the clinical characteristics of patients with PC in different immune status, we retrospectively investigated the clinical, radiological, and treatment profiles of immunocompetent and immunocompromised patients with PC during a 10-year period (2008–2017). As a result, out of 136 patients, 94 (69.1%) were immunocompromised hosts. For the PC patients without CNS involvement, higher percentage of immunocompetent patients (39.5%, 15/38) had asymptomatic presentation than immunocompromised patients (6.3%, 3/48) (P < 0.05). Multiple pulmonary nodules (72.7%, 56/77), ground-glass attenuation/interstitial changes (94.4%, 17/18) and cavitation (88.6%, 31/35) were significantly frequent in immunocompromised patients (P < 0.05). A total of 47 patients were misdiagnosed as tuberculosis or tumors based on CT signs. PC was likely to be misdiagnosed as tuberculosis in immunocompromised patients (88.2%, 15/17), and tumor was more likely to be considered in immunocompetent patients (43.3%, 13/30). Immunocompetent patients accounted for 80% (24/30) of patients with definite diagnosis on surgical lung biopsy. Fluconazole monotherapy can achieve good clinical outcome in most PC patients without central nervous system (CNS) involvement (91.5%, 54/59). After 3 months of treatment, 92.7% (38/41) patients have improved imaging findings. In conclusion, PC has diverse imaging manifestations and it is easily misdiagnosed. Lobectomy should be carefully selected in immunocompetent patients with a single lung lesion. Fluconazole monotherapy is preferred for PC patients without CNS involvement.
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29
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Adewumi OM, Dukhovlinova E, Shehu NY, Zhou S, Council OD, Akanbi MO, Taiwo B, Ogunniyi A, Robertson K, Kanyama C, Hosseinipour MC, Swanstrom R. HIV-1 Central Nervous System Compartmentalization and Cytokine Interplay in Non-Subtype B HIV-1 Infections in Nigeria and Malawi. AIDS Res Hum Retroviruses 2020; 36:490-500. [PMID: 31914800 DOI: 10.1089/aid.2019.0245] [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: 12/15/2022] Open
Abstract
HIV-1 compartmentalization in the central nervous system (CNS) and its contribution to neurological disease have been well documented. Previous studies were conducted among people infected with subtypes B or C where CNS compartmentalization has been observed when comparing viral sequences in the blood to virus in cerebrospinal fluid (CSF). However, little is known about CNS compartmentalization in other HIV-1 subtypes. Using a deep sequencing approach with Primer ID, we conducted a cross-sectional study among Nigerian and Malawian HIV-1 cohorts with or without fungal Cryptococcus infection diagnosed as cryptococcal meningitis (CM) to determine the extent of CSF/CNS compartmentalization with CM. Paired plasma and CSF samples from 45 participants were also analyzed for cytokine/chemokine levels. Viral populations comparing virus in the blood and the CSF ranged from compartmentalized to equilibrated, including minor or partial compartmentalization or clonal amplification of a single viral sequence. The frequency of compartmentalized viral populations in the blood and CSF was similar between the CM- and CM+ participants. We confirmed the potential to see compartmentalization with subtype C infection and have also documented CNS compartmentalization of an HIV-1 subtype G infection. Cytokine profiles indicated a proinflammatory environment, especially within the CSF/CNS. However, sCD163 was suppressed in the CSF in the presence of CM, perhaps due to elevated levels of IL-4, which were also a feature of the cytokine profile, showing a distinct cytokine profile with CM.
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Affiliation(s)
- Olubusuyi Moses Adewumi
- Department of Virology, College of Medicine, University of Ibadan, Ibadan, Nigeria
- Infectious Disease Institute, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Elena Dukhovlinova
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Nathan Y. Shehu
- Department of Medicine, Jos University Teaching Hospital, Jos, Nigeria
| | - Shuntai Zhou
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Olivia D. Council
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Maxwell O. Akanbi
- Department of Medicine, Jos University Teaching Hospital, Jos, Nigeria
- Health Sciences Integrated PhD Program, Center for Education in Health Sciences, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
| | - Babafemi Taiwo
- Department of Medicine, Northwestern University, Chicago, Illinois, USA
| | - Adesola Ogunniyi
- Department of Medicine, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Kevin Robertson
- Department of Neurology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Cecilia Kanyama
- UNC Project-Malawi, Kamuzu Central Hospital, Lilongwe, Malawi
| | - Mina C. Hosseinipour
- UNC Project-Malawi, Kamuzu Central Hospital, Lilongwe, Malawi
- Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Ronald Swanstrom
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
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30
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Coelho C, Farrer RA. Pathogen and host genetics underpinning cryptococcal disease. ADVANCES IN GENETICS 2020; 105:1-66. [PMID: 32560785 DOI: 10.1016/bs.adgen.2020.02.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Cryptococcosis is a severe fungal disease causing 220,000 cases of cryptococcal meningitis yearly. The etiological agents of cryptococcosis are taxonomically grouped into at least two species complexes belonging to the genus Cryptococcus. All of these yeasts are environmentally ubiquitous fungi (often found in soil, leaves and decaying wood, tree hollows, and associated with bird feces especially pigeon guano). Infection in a range of animals including humans begins following inhalation of spores or aerosolized yeasts. Recent advances provide fundamental insights into the factors from both the pathogen and its hosts which influence pathogenesis and disease. The complex interactions leading to disease in mammalian hosts have also updated from the availability of better genomic tools and datasets. In this review, we discuss recent genetic research on Cryptococcus, covering the epidemiology, ecology, and evolution of Cryptococcus pathogenic species. We also discuss the insights into the host immune response obtained from the latest genetic modified host models as well as insights from monogenic disorders in humans. Finally we highlight outstanding questions that can be answered in the near future using bioinformatics and genomic tools.
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Affiliation(s)
- Carolina Coelho
- Medical Research Council Centre for Medical Mycology at the University of Exeter, Exeter, United Kingdom
| | - Rhys A Farrer
- Medical Research Council Centre for Medical Mycology at the University of Exeter, Exeter, United Kingdom.
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31
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Omar Faruk SM, Hazra I, Mondal S, Datta A, Moitra S, Das PK, Mishra R, Chaudhuri S. T11TS immunotherapy potentiates the repressed calcineurin-NFAT signalling pathway of T cells in Cryptococcus neoformans infected rats: a cue towards T-cell activation for antifungal immunity. J Appl Microbiol 2020; 129:753-767. [PMID: 32145053 DOI: 10.1111/jam.14631] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 02/16/2020] [Accepted: 03/02/2020] [Indexed: 12/24/2022]
Abstract
AIMS To examine the modulation of the interacting partners of the calcineurin (CaN)-NFAT pathway in T cells during Cryptococcus neoformans fungal infection and post-T11TS immunotherapy. METHODS AND RESULTS Wistar rats were infected with C. neoformans and followed by immunotherapy with immune-potentiator T11TS. T cells were analysed by flow cytometry, immunoblotting and nuclear translocation study. The signalling proteins LCK, FYN, LAT, PLCγ1 and CaN in T cells were regulated by C. neoformans infection resulting in reduced nuclear translocation of NFAT and IL-2 expression. Following T11TS immunotherapy, the expressions of the above-mentioned proteins were boosted and thus resulting in the clearance of C. neoformans from lung and spleen. CONCLUSIONS The precise mechanism of suppression of the T-cell function by C. neoformans is still unknown. Previously, we have shown that T11TS positively regulates the function of T cells to abrogate glioma and other immunosuppressive conditions. T11TS immunotherapy increased the expression of the above signalling partners of the CaN-NFAT pathway in T cells and improved nuclear retention of NFAT. As a result, an increased IL-2 expression leads to activation and proliferation of T cells. SIGNIFICANCE AND IMPACT OF THE STUDY Our results demonstrate the role of T11TS in restoring the CaN-NFAT signalling pathway in T cells. It identifies T11TS as an immunotherapeutic agent with potential clinical outcomes to counteract C. neoformans infection.
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Affiliation(s)
- S M Omar Faruk
- Department of Laboratory Medicine, School of Tropical Medicine, Kolkata, West Bengal, India.,Department of Physiology, University of Calcutta, Kolkata, West Bengal, India
| | - I Hazra
- Department of Laboratory Medicine, School of Tropical Medicine, Kolkata, West Bengal, India
| | - S Mondal
- Department of Laboratory Medicine, School of Tropical Medicine, Kolkata, West Bengal, India
| | - A Datta
- Department of Laboratory Medicine, School of Tropical Medicine, Kolkata, West Bengal, India
| | - S Moitra
- Department of Laboratory Medicine, School of Tropical Medicine, Kolkata, West Bengal, India
| | - P K Das
- Department of Laboratory Medicine, School of Tropical Medicine, Kolkata, West Bengal, India
| | - R Mishra
- Department of Physiology, University of Calcutta, Kolkata, West Bengal, India
| | - S Chaudhuri
- Department of Laboratory Medicine, School of Tropical Medicine, Kolkata, West Bengal, India
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Campuzano A, Castro-Lopez N, Martinez AJ, Olszewski MA, Ganguly A, Leopold Wager C, Hung CY, Wormley FL. CARD9 Is Required for Classical Macrophage Activation and the Induction of Protective Immunity against Pulmonary Cryptococcosis. mBio 2020; 11:e03005-19. [PMID: 31911495 PMCID: PMC6946806 DOI: 10.1128/mbio.03005-19] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Accepted: 11/20/2019] [Indexed: 01/08/2023] Open
Abstract
Caspase recruitment domain-containing protein 9 (CARD9) is a critical adaptor molecule triggered by the interaction of C-type lectin receptors (CLRs) with carbohydrate motifs found in fungi. Consequently, clinical and animal studies indicate that CARD9 is an important regulator of protective immunity against fungal pathogens. Previous studies suggest that CARD9 is important for the induction of protection against Cryptococcus neoformans, an opportunistic fungal pathogen that causes life-threatening infections of the central nervous system in immunocompromised patients. However, the effect of CARD9 deficiency on the induction of protective immune responses against C. neoformans is unknown. Immunization with a C. neoformans mutant that overexpresses the transcription factor zinc finger 2, denoted LW10, results in protection against an otherwise lethal challenge with wild-type (WT) C. neoformans Our results showed that CARD9 is essential for the induction of vaccine-mediated immunity against C. neoformans infection. We observed significant decreases in interleukin-17 (IL-17) production and significant increases in Th2-type cytokine (IL-4, IL-5, and IL-13) production in CARD9-deficient mice after inoculation with strain LW10. While leukocyte infiltration to the lungs of CARD9-deficient mice was similar in LW10 and WT C. neoformans-infected mice, macrophages derived from CARD9-deficient mice inherently skewed toward an M2 activation phenotype, were unable to contain the growth of LW10, and failed to produce nitric oxide in response to infection with LW10 or stimulation with lipopolysaccharide. These results suggest that CARD9-mediated signaling is required for M1 macrophage activation and fungicidal activity necessary for the induction of vaccine-mediated immunity against C. neoformansIMPORTANCECryptococcus neoformans is a fungal pathogen that is found throughout the environment and can cause life-threatening infections of the lung and central nervous system in severely immunocompromised individuals. Caspase recruitment domain-containing protein 9 (CARD9) is a critical molecule that is activated after interactions of C-type lectin receptors (CLRs) found on the surfaces of specific immune cells, with carbohydrate structures associated with fungi. Patients with defects in CARD9 are significantly more susceptible to a multitude of fungal infections. C. neoformans contains several carbohydrate structures that interact with CLRs on immune cells and activate CARD9. Consequently, these studies evaluated the necessity of CARD9 for the induction of protective immunity against C. neoformans infection. These results are important, as they advance our understanding of cryptococcal pathogenesis and host factors necessary for the induction of protective immunity against C. neoformans.
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Affiliation(s)
- Althea Campuzano
- Department of Biology, South Texas Center for Emerging Infectious Diseases, The University of Texas at San Antonio, San Antonio, Texas, USA
| | - Natalia Castro-Lopez
- Department of Biology, South Texas Center for Emerging Infectious Diseases, The University of Texas at San Antonio, San Antonio, Texas, USA
| | - Amanda J Martinez
- Department of Biology, South Texas Center for Emerging Infectious Diseases, The University of Texas at San Antonio, San Antonio, Texas, USA
| | - Michal A Olszewski
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Michigan Medicine University, Ann Arbor, Michigan, USA
- VA Ann Arbor Healthcare System, Research Service, Ann Arbor, Michigan, USA
| | - Anutosh Ganguly
- VA Ann Arbor Healthcare System, Research Service, Ann Arbor, Michigan, USA
- Division of Hepatobiliary Surgery, Department of Surgery, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Chrissy Leopold Wager
- Department of Biology, South Texas Center for Emerging Infectious Diseases, The University of Texas at San Antonio, San Antonio, Texas, USA
| | - Chiung-Yu Hung
- Department of Biology, South Texas Center for Emerging Infectious Diseases, The University of Texas at San Antonio, San Antonio, Texas, USA
| | - Floyd L Wormley
- Department of Biology, South Texas Center for Emerging Infectious Diseases, The University of Texas at San Antonio, San Antonio, Texas, USA
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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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34
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Zafar H, Altamirano S, Ballou ER, Nielsen K. A titanic drug resistance threat in Cryptococcus neoformans. Curr Opin Microbiol 2019; 52:158-164. [PMID: 31765991 DOI: 10.1016/j.mib.2019.11.001] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Revised: 10/01/2019] [Accepted: 11/01/2019] [Indexed: 10/25/2022]
Abstract
Increasing resistance to frontline antifungals is a growing threat to global health. In the face of high rates of relapse for patients with cryptococcal meningitis and frequent drug resistance in clinical isolates, recent insights into Cryptococcus neoformans morphogenesis and genome plasticity take on new and urgent meaning. Here we review the state of the understanding of mechanisms of drug resistance in the context of host-relevant changes in Cryptococcus morphology and cell ploidy.
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Affiliation(s)
- Hanna Zafar
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - Sophie Altamirano
- Department of Microbiology and Immunology, University of Minnesota, Minneapolis, MN, 55455 USA
| | - Elizabeth R Ballou
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK.
| | - Kirsten Nielsen
- Department of Microbiology and Immunology, University of Minnesota, Minneapolis, MN, 55455 USA.
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Fa Z, Xu J, Yi J, Sang J, Pan W, Xie Q, Yang R, Fang W, Liao W, Olszewski MA. TNF-α-Producing Cryptococcus neoformans Exerts Protective Effects on Host Defenses in Murine Pulmonary Cryptococcosis. Front Immunol 2019; 10:1725. [PMID: 31404168 PMCID: PMC6677034 DOI: 10.3389/fimmu.2019.01725] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Accepted: 07/09/2019] [Indexed: 12/13/2022] Open
Abstract
Tumor necrosis factor alpha (TNF-α) plays a critical role in the control of cryptococcal infection, and its insufficiency promotes cryptococcal persistence. To explore the therapeutic potential of TNF-α supplementation as a booster of host anti-cryptococcal responses, we engineered a C. neoformans strain expressing murine TNF-α. Using a murine model of pulmonary cryptococcosis, we demonstrated that TNF-α-producing C. neoformans strain enhances protective elements of host response including preferential T-cell accumulation and improved Th1/Th2 cytokine balance, diminished pulmonary eosinophilia and alternative activation of lung macrophages at the adaptive phase of infection compared to wild type strain-infected mice. Furthermore, TNF-α expression by C. neoformans enhanced the fungicidal activity of macrophages in vitro. Finally, mice infected with the TNF-α-producing C. neoformans strain showed improved fungal control and considerably prolonged survival compared to wild type strain-infected mice, but could not induce sterilizing immunity. Taken together, our results support that TNF-α expression by an engineered C. neoformans strain while insufficient to drive complete immune protection, strongly enhanced protective responses during primary cryptococcal infection.
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Affiliation(s)
- Zhenzong Fa
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Health System, Ann Arbor, MI, United States.,Shanghai Key Laboratory of Molecular Medical Mycology, Department of Dermatology, Changzheng Hospital, Naval Medical University, Shanghai, China.,Department of Dermatology, The Sixth Medical Center of PLA General Hospital, Beijing, China
| | - Jintao Xu
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Health System, Ann Arbor, MI, United States.,Ann Arbor VA Health System, Department of Veterans Affairs Health System, Ann Arbor, MI, United States
| | - Jiu Yi
- Shanghai Key Laboratory of Molecular Medical Mycology, Department of Dermatology, Changzheng Hospital, Naval Medical University, Shanghai, China
| | - Junjun Sang
- Shanghai Key Laboratory of Molecular Medical Mycology, Department of Dermatology, Changzheng Hospital, Naval Medical University, Shanghai, China
| | - Weihua Pan
- Shanghai Key Laboratory of Molecular Medical Mycology, Department of Dermatology, Changzheng Hospital, Naval Medical University, Shanghai, China
| | - Qun Xie
- Department of Anesthesiology, The Fourth Medical Center of PLA General Hospital, Beijing, China
| | - Runping Yang
- Department of Dermatology, The Sixth Medical Center of PLA General Hospital, Beijing, China
| | - Wei Fang
- Shanghai Key Laboratory of Molecular Medical Mycology, Department of Dermatology, Changzheng Hospital, Naval Medical University, Shanghai, China
| | - Wanqing Liao
- Shanghai Key Laboratory of Molecular Medical Mycology, Department of Dermatology, Changzheng Hospital, Naval Medical University, Shanghai, China
| | - Michal A Olszewski
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Health System, Ann Arbor, MI, United States.,Ann Arbor VA Health System, Department of Veterans Affairs Health System, Ann Arbor, MI, United States
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36
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Decote-Ricardo D, LaRocque-de-Freitas IF, Rocha JDB, Nascimento DO, Nunes MP, Morrot A, Freire-de-Lima L, Previato JO, Mendonça-Previato L, Freire-de-Lima CG. Immunomodulatory Role of Capsular Polysaccharides Constituents of Cryptococcus neoformans. Front Med (Lausanne) 2019; 6:129. [PMID: 31275938 PMCID: PMC6593061 DOI: 10.3389/fmed.2019.00129] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Accepted: 05/24/2019] [Indexed: 12/13/2022] Open
Abstract
Cryptococcosis is a systemic fungal infection caused by Cryptococcus neoformans. In immunocompetent patients, cryptococcal infection is often confined to the lungs. In immunocompromised individuals, C. neoformans may cause life-threatening illness, either from novel exposure or through reactivation of a previously acquired latent infection. For example, cryptococcal meningitis is a severe clinical disease that can manifest in people that are immunocompromised due to AIDS. The major constituents of the Cryptococcus polysaccharide capsule, glucuronoxylomannan (GXM), and galactoxylomannan (GalXM), also known as glucuronoxylomanogalactan (GXMGal), are considered the primary virulence factors of Cryptococcus. Despite the predominance of GXM in the polysaccharide capsule, GalXM has more robust immunomodulatory effects on host cellular immunity. This review summarizes current knowledge regarding host-Crytococcus neoformans interactions and the role of capsular polysaccharides in host immunomodulation. Future studies will likely facilitate a better understanding of the mechanisms involved in antigenic recognition and host immune response to C. neoformans and lead to the development of new therapeutic pathways for cryptococcal infection.
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Affiliation(s)
- Debora Decote-Ricardo
- Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, Seropédica, Brazil
| | | | - Juliana Dutra B Rocha
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Danielle O Nascimento
- Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, Seropédica, Brazil.,Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Marise P Nunes
- Laboratório de Imunoparasitologia, Instituto Oswaldo Cruz, FIOCRUZ, Rio de Janeiro, Brazil
| | - Alexandre Morrot
- Laboratório de Imunoparasitologia, Instituto Oswaldo Cruz, FIOCRUZ, Rio de Janeiro, Brazil.,Faculdade de Medicina, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Leonardo Freire-de-Lima
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Jose Osvaldo Previato
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Lucia Mendonça-Previato
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
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Shourian M, Qureshi ST. Resistance and Tolerance to Cryptococcal Infection: An Intricate Balance That Controls the Development of Disease. Front Immunol 2019; 10:66. [PMID: 30761136 PMCID: PMC6361814 DOI: 10.3389/fimmu.2019.00066] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Accepted: 01/11/2019] [Indexed: 12/25/2022] Open
Abstract
Cryptococcus neoformans is a ubiquitous environmental yeast and a leading cause of invasive fungal infection in humans. The most recent estimate of global disease burden includes over 200,000 cases of cryptococcal meningitis each year. Cryptococcus neoformans expresses several virulence factors that may have originally evolved to protect against environmental threats, and human infection may be an unintended consequence of these acquired defenses. Traditionally, C. neoformans has been viewed as a purely opportunistic pathogen that targets severely immune compromised hosts; however, during the past decade the spectrum of susceptible individuals has grown considerably. In addition, the closely related strain Cryptococcus gattii has recently emerged in North America and preferentially targets individuals with intact immunity. In parallel to the changing epidemiology of cryptococcosis, an increasing role for host immunity in the pathogenesis of severe disease has been elucidated. Initially, the HIV/AIDS epidemic revealed the capacity of C. neoformans to cause host damage in the absence of adaptive immunity. Subsequently, the development and clinical implementation of highly active antiretroviral treatment (HAART) led to recognition of an immune reconstitution inflammatory syndrome (IRIS) in a subset of HIV+ individuals, demonstrating the pathological role of host immunity in disease. A post-infectious inflammatory syndrome (PIIRS) characterized by abnormal T cell-macrophage activation has also been documented in HIV-negative individuals following antifungal therapy. These novel clinical conditions illustrate the highly complex host-pathogen relationship that underlies severe cryptococcal disease and the intricate balance between tolerance and resistance that is necessary for effective resolution. In this article, we will review current knowledge of the interactions between cryptococci and mammalian hosts that result in a tolerant phenotype. Future investigations in this area have potential for translation into improved therapies for affected individuals.
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Affiliation(s)
- Mitra Shourian
- Translational Research in Respiratory Diseases Program, Meakins-Christie Laboratories, Research Institute of the McGill University Health Centre, Montreal, QC, Canada.,Division of Experimental Medicine, Department of Medicine, McGill University Health Centre, Montreal, QC, Canada
| | - Salman T Qureshi
- Translational Research in Respiratory Diseases Program, Meakins-Christie Laboratories, Research Institute of the McGill University Health Centre, Montreal, QC, Canada.,Division of Experimental Medicine, Department of Medicine, McGill University Health Centre, Montreal, QC, Canada
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38
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Involvement of the capsular GalXM-induced IL-17 cytokine in the control of Cryptococcus neoformans infection. Sci Rep 2018; 8:16378. [PMID: 30401972 PMCID: PMC6219535 DOI: 10.1038/s41598-018-34649-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Accepted: 10/22/2018] [Indexed: 12/22/2022] Open
Abstract
Cryptococcus neoformans is an opportunistic fungus that can cause lethal brain infections in immunosuppressed individuals. Infection usually occurs via the inhalation of a spore or desiccated yeast which can then disseminate from the lung to the brain and other tissues. Dissemination and disease is largely influence by the production of copious amounts of cryptococcal polysaccharides, both which are secreted to the extracellular environment or assembled into a thick capsule surrounding the cell body. There are two important polysaccharides: glucuronoxylomannan (GXM) and galactoxylomannan, also called as glucuronoxylomanogalactan (GXMGal or GalXM). Although GXM is more abundant, GalXM has a more potent modulatory effect. In the present study, we show that GalXM is a potent activator of murine dendritic cells, and when co-cultured with T cells, induces a Th17 cytokine response. We also demonstrated that treating mice with GalXM prior to infection with C. neoformans protects from infection, and this phenomenon is dependent on IL-6 and IL-17. These findings help us understand the immune biology of capsular polysaccharides in fungal pathogenesis.
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ATG Genes Influence the Virulence of Cryptococcus neoformans through Contributions beyond Core Autophagy Functions. Infect Immun 2018; 86:IAI.00069-18. [PMID: 29986893 DOI: 10.1128/iai.00069-18] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Accepted: 07/03/2018] [Indexed: 12/31/2022] Open
Abstract
The process of autophagy is conserved among all eukaryotes from yeast to humans and is mainly responsible for bulk degradation of cellular contents and nutrient recycling during starvation. Autophagy has been suggested to play a role in the pathogenesis of the opportunistic human fungal pathogen Cryptococcus neoformans, potentially through a contribution to the export of virulence factors. In this study, we showed that deletion of each of the ATG1, ATG7, ATG8, and ATG9 genes in C. neoformans leads to autophagy-related phenotypes, including impaired amino acid homeostasis under nitrogen starvation. In addition, the atgΔ mutants were hypersensitive to inhibition of the ubiquitin-proteasome system, a finding consistent with a role in amino acid homeostasis. Although each atgΔ mutant was not markedly impaired in virulence factor production in vitro, we found that all four ATG genes contribute to C. neoformans virulence in a murine inhalation model of cryptococcosis. Interestingly, these mutants displayed significant differences in their ability to promote disease development. A more detailed investigation of virulence for the atg1Δ and atg8Δ mutants revealed that both strains stimulated an exaggerated host immune response, which, in turn, contributed to disease severity. Overall, our results suggest that different ATG genes are involved in nonautophagic functions and contribute to C. neoformans virulence beyond their core functions in autophagy.
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40
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Jarvis JN, Harrison TS. Understanding Causal Pathways in Cryptococcal Meningitis Immune Reconstitution Inflammatory Syndrome. J Infect Dis 2018; 219:344-346. [DOI: 10.1093/infdis/jiy448] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Accepted: 07/12/2018] [Indexed: 11/13/2022] Open
Affiliation(s)
- Joseph N Jarvis
- Department of Clinical Research, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
- Botswana Harvard AIDS Institute Partnership, Gaborone, Botswana
- Botswana University of Pennsylvania Partnership, Gaborone, Botswana
- Division of Infectious Diseases, Perelman School of Medicine, University of Pennsylvania, Philadelphia
| | - Thomas S Harrison
- Centre for Global Health, Institute for Infection and Immunity, St. George’s University of London, United Kingdom
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Special Issue: Mucosal Fungal Infections. J Fungi (Basel) 2018; 4:jof4020043. [PMID: 29587454 PMCID: PMC6023363 DOI: 10.3390/jof4020043] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2018] [Revised: 03/25/2018] [Accepted: 03/25/2018] [Indexed: 12/25/2022] Open
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42
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Campuzano A, Wormley FL. Innate Immunity against Cryptococcus, from Recognition to Elimination. J Fungi (Basel) 2018. [PMID: 29518906 PMCID: PMC5872336 DOI: 10.3390/jof4010033] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Cryptococcus species, the etiological agents of cryptococcosis, are encapsulated fungal yeasts that predominantly cause disease in immunocompromised individuals, and are responsible for 15% of AIDS-related deaths worldwide. Exposure follows the inhalation of the yeast into the lung alveoli, making it incumbent upon the pattern recognition receptors (PRRs) of pulmonary phagocytes to recognize highly conserved pathogen-associated molecular patterns (PAMPS) of fungi. The main challenges impeding the ability of pulmonary phagocytes to effectively recognize Cryptococcus include the presence of the yeast's large polysaccharide capsule, as well as other cryptococcal virulence factors that mask fungal PAMPs and help Cryptococcus evade detection and subsequent activation of the immune system. This review will highlight key phagocyte cell populations and the arsenal of PRRs present on these cells, such as the Toll-like receptors (TLRs), C-type lectin receptors, NOD-like receptors (NLRs), and soluble receptors. Additionally, we will highlight critical cryptococcal PAMPs involved in the recognition of Cryptococcus. The question remains as to which PRR-ligand interaction is necessary for the recognition, phagocytosis, and subsequent killing of Cryptococcus.
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Affiliation(s)
- Althea Campuzano
- Department of Biology, The University of Texas at San Antonio, San Antonio, TX 78249, USA.
- South Texas Center for Emerging Infectious Diseases, The University of Texas at San Antonio, San Antonio, TX 78249, USA.
| | - Floyd L Wormley
- Department of Biology, The University of Texas at San Antonio, San Antonio, TX 78249, USA.
- South Texas Center for Emerging Infectious Diseases, The University of Texas at San Antonio, San Antonio, TX 78249, USA.
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