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Mattos MS, Vandendriessche S, Waisman A, Marques PE. The immunology of B-1 cells: from development to aging. Immun Ageing 2024; 21:54. [PMID: 39095816 PMCID: PMC11295433 DOI: 10.1186/s12979-024-00455-y] [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: 06/05/2024] [Accepted: 07/17/2024] [Indexed: 08/04/2024]
Abstract
B-1 cells have intricate biology, with distinct function, phenotype and developmental origin from conventional B cells. They generate a B cell receptor with conserved germline characteristics and biased V(D)J recombination, allowing this innate-like lymphocyte to spontaneously produce self-reactive natural antibodies (NAbs) and become activated by immune stimuli in a T cell-independent manner. NAbs were suggested as "rheostats" for the chronic diseases in advanced age. In fact, age-dependent loss of function of NAbs has been associated with clinically-relevant diseases in the elderly, such as atherosclerosis and neurodegenerative disorders. Here, we analyzed comprehensively the ontogeny, phenotypic characteristics, functional properties and emerging roles of B-1 cells and NAbs in health and disease. Additionally, after navigating through the complexities of B-1 cell biology from development to aging, therapeutic opportunities in the field are discussed.
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Affiliation(s)
- Matheus Silvério Mattos
- Laboratory of Molecular Immunology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, 3000, Louvain, Belgium
| | - Sofie Vandendriessche
- Laboratory of Molecular Immunology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, 3000, Louvain, Belgium
| | - Ari Waisman
- Institute for Molecular Medicine, University Medical Centre of the Johannes Gutenberg University of Mainz, Mainz, Germany
| | - Pedro Elias Marques
- Laboratory of Molecular Immunology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, 3000, Louvain, Belgium.
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2
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Wang Z, Shao J. Fungal vaccines and adjuvants: a tool to reveal the interaction between host and fungi. Arch Microbiol 2024; 206:293. [PMID: 38850421 DOI: 10.1007/s00203-024-04010-7] [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: 04/06/2024] [Revised: 05/09/2024] [Accepted: 05/17/2024] [Indexed: 06/10/2024]
Abstract
Fungal infections are incurring high risks in a range from superficial mucosal discomforts (such as oropharyngeal candidiasis and vulvovaginal candidiasis) to disseminated life-threatening diseases (such as invasive pulmonary aspergillosis and cryptococcal meningitis) and becoming a global health problem in especially immunodeficient population. The major obstacle to conquer fungal harassment lies in the presence of increasing resistance to conventional antifungal agents used in newly clinically isolated strains. Although recombinant cytokines and mono-/poly-clonal antibodies are added into antifungal armamentarium, more effective antimycotic drugs are exceedingly demanded. It is comforting that the development of fungal vaccines and adjuvants opens up a window to brighten the prospective way in the diagnosis, prevention and treatment of fungal assaults. In this review, we focus on the progression of several major fungal vaccines devised for the control of Candida spp., Aspergillus spp., Cryptococcus spp., Coccidioides spp., Paracoccidioides spp., Blastomyces spp., Histoplasma spp., Pneumocystis spp. as well as the adjuvants adopted. We then expound the interaction between fungal vaccines/adjuvants and host innate (macrophages, dendritic cells, neutrophils), humoral (IgG, IgM and IgA) and cellular (Th1, Th2, Th17 and Tc17) immune responses which generally experience immune recognition of pattern recognition receptors, activation of immune cells, and clearance of invaded fungi. Furthermore, we anticipate an in-depth understanding of immunomodulatory properties of univalent and multivalent vaccines against diverse opportunistic fungi, providing helpful information in the design of novel fungal vaccines and adjuvants.
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Affiliation(s)
- Zixu Wang
- Laboratory of Anti-Infection and Immunity, College of Integrated Chinese and Western Medicine (College of Life Science), Anhui University of Chinese Medicine, Zhijing Building, 350 Longzihu Road, Xinzhan District, Hefei, 230012, Anhui, People's Republic of China
| | - Jing Shao
- Laboratory of Anti-Infection and Immunity, College of Integrated Chinese and Western Medicine (College of Life Science), Anhui University of Chinese Medicine, Zhijing Building, 350 Longzihu Road, Xinzhan District, Hefei, 230012, Anhui, People's Republic of China.
- Institute of Integrated Traditional Chinese and Western Medicine, Anhui Academy of Chinese Medicine, Zhijing Building, 350 Longzihu Road, Xinzhan District, Hefei, 230012, Anhui, People's Republic of China.
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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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Iraji D, Oftedal BE, Wolff ASB. Th17 Cells: Orchestrators of Mucosal Inflammation and Potential Therapeutic Targets. Crit Rev Immunol 2023; 43:25-52. [PMID: 37831521 DOI: 10.1615/critrevimmunol.2023050360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2023]
Abstract
T helper 17 (Th17) cells represent a specialized subgroup of effector CD4+ T cells known for their role in provoking neutrophil-driven tissue inflammation, particularly within mucosal tissues. Although they are pivotal for defending the host against extracellular bacteria and fungi, they have also been associated with development of various T cell-mediated inflammatory conditions, autoimmune diseases, and even cancer. Notably, Th17 cells exhibit a dual nature, with different Th17 cell subtypes showcasing distinct effector functions and varying capacities to incite autoimmune tissue inflammation. Furthermore, Th17 cells exhibit significant plasticity, which carries important functional implications, both in terms of their expression of cytokines typically associated with other effector T cell subsets and in their interactions with regulatory CD4+ T cells. The intricate balance of Th17 cytokines can also be a double-edged sword in inflammation, autoimmunity, and cancer. Within this article, we delve into the mechanisms that govern the differentiation, function, and adaptability of Th17 cells. We culminate with an exploration of therapeutic potentials in harnessing the power of Th17 cells and their cytokines. Targeted interventions to modulate Th17 responses are emerging as promising strategies for autoimmunity, inflammation, and cancer treatment. By precisely fine-tuning Th17-related pathways, we may unlock new avenues for personalized therapeutic approaches, aiming to restore immune balance, alleviate the challenges of these disorders, and ultimately enhance the quality of life for individuals affected by them.
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Affiliation(s)
- Dorsa Iraji
- Department of Clinical Science, University of Bergen, Bergen, Norway
| | - Bergithe E Oftedal
- Department of Clinical Science, University of Bergen, Bergen, Norway; Department of Medicine, Haukeland University Hospital, Bergen, Norway
| | - Anette S B Wolff
- Department of Clinical Science, University of Bergen, Bergen, Norway; Department of Medicine, Haukeland University Hospital, Bergen, Norway
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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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Abstract
Cryptococcosis is a disease caused by the pathogenic fungi Cryptococcus neoformans and Cryptococcus gattii, both environmental fungi that cause severe pneumonia and may even lead to cryptococcal meningoencephalitis. Although C. neoformans affects more fragile individuals, such as immunocompromised hosts through opportunistic infections, C. gattii causes a serious indiscriminate primary infection in immunocompetent individuals. Typically seen in tropical and subtropical environments, C. gattii has increased its endemic area over recent years, largely due to climatic factors that favor contagion in warmer climates. It is important to point out that not only C. gattii, but the Cryptococcus species complex produces a polysaccharidic capsule with immunomodulatory properties, enabling the pathogenic species of Cryptococccus to subvert the host immune response during the establishment of cryptococcosis, facilitating its dissemination in the infected organism. C. gattii causes a more severe and difficult-to-treat infection, with few antifungals eliciting an effective response during chronic treatment. Much of the immunopathology of this cryptococcosis is still poorly understood, with most studies focusing on cryptococcosis caused by the species C. neoformans. C. gattii became more important in the epidemiological scenario with the outbreaks in the Pacific Northwest of the United States, which resulted in phylogenetic studies of the virulent variant responsible for the severe infection in the region. Since then, the study of cryptococcosis caused by C. gattii has helped researchers understand the immunopathological aspects of different variants of this pathogen.
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Prevel R, Guillotin V, Imbert S, Blanco P, Delhaes L, Duffau P. Central Nervous System Cryptococcosis in Patients With Sarcoidosis: Comparison With Non-sarcoidosis Patients and Review of Potential Pathophysiological Mechanisms. Front Med (Lausanne) 2022; 9:836886. [PMID: 35425769 PMCID: PMC9002233 DOI: 10.3389/fmed.2022.836886] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Accepted: 03/02/2022] [Indexed: 11/13/2022] Open
Abstract
Introduction Cryptococcus spp. infection of the central nervous system (CINS) is a devastating opportunistic infection that was historically described in patients with acquired immunodeficiency syndrome (AIDS). Cryptococcus spp. infections are also associated with sarcoidosis; the impairment of cell-mediated immunity and long-term corticosteroid therapy being evoked to explain this association. Nevertheless, this assertion is debated and the underlying pathophysiological mechanisms are still unknown. The aims of this study were (i) to describe the clinical and biological presentation, treatments, and outcomes of CINS patients with and without sarcoidosis and (ii) to review the pathophysiological evidence underlying this clinical association. Patients and Methods Every patient with positive cerebrospinal fluid (CSF) cryptococcal antigen testing, India ink preparation, and/or culture from January 2015 to December 2020 at a tertiary university hospital were included, and patients with sarcoidosis were compared with non-sarcoidosis patients. Quantitative variables are presented as mean ± SD and are compared using the Mann-Whitney Wilcoxon rank-sum test. Categorical variables are expressed as the number of patients (percentage) and compared using the χ2 or Fisher's tests. Results During the study period, 16 patients experienced CINS, of whom 5 (31%) were associated with sarcoidosis. CINS symptoms, biological, and CSF features were similar between CINS patients with and without sarcoidosis except regarding CD4 cells percentages and CD4/CD8 ratio that was higher in those with sarcoidosis (47 ± 12 vs. 22 ± 18, p = 0.02 and 2.24 ± 1.42 vs. 0.83 ± 1.10, p = 0.03, respectively). CINS patients with sarcoidosis had less often positive blood antigen testing than those without sarcoidosis (2/5 vs. 11/11, p = 0.02). CINS patients with and without sarcoidosis were treated with similar drugs, but patients with sarcoidosis had a shorter length of treatment. CD4 cell levels do not seem to explain the association between sarcoidosis and cryptococcosis. Conclusion Sarcoidosis was the most frequently associated condition with CINS in this study. CINS patients associated with sarcoidosis had overall similar clinical and biological presentation than CINS patients associated with other conditions but exhibited a lower rate of positive blood cryptococcal antigen testing and higher CD4/CD8 T cells ratio. Pathophysiological mechanisms underlying this association remain poorly understood but B-1 cell deficiency or lack of IgM could be a part of the explanation. Another plausible mechanism is the presence of anti-granulocyte-macrophage colony-stimulating factor (GM-CSF) antibodies in a subset of patients with sarcoidosis, which could impair macrophage phagocytic function. Further studies are strongly needed to better understand those mechanisms and to identify at-risk patients.
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Affiliation(s)
- Renaud Prevel
- CHU Bordeaux, Internal Medicine Department, Bordeaux, France.,Univ Bordeaux, Centre de Recherche Cardio-Thoracique de Bordeaux, Inserm UMR 1045, Bordeaux, France
| | | | - Sébastien Imbert
- Univ Bordeaux, Centre de Recherche Cardio-Thoracique de Bordeaux, Inserm UMR 1045, Bordeaux, France.,CHU Bordeaux, Mycology-Parasitology Department, CIC 1401, Bordeaux, France
| | - Patrick Blanco
- CHU Bordeaux, Immunology Department, Bordeaux, France.,Univ Bordeaux, CNRS ImmunoConcEpT UMR 5164, Bordeaux, France
| | - Laurence Delhaes
- Univ Bordeaux, Centre de Recherche Cardio-Thoracique de Bordeaux, Inserm UMR 1045, Bordeaux, France.,CHU Bordeaux, Mycology-Parasitology Department, CIC 1401, Bordeaux, France
| | - Pierre Duffau
- CHU Bordeaux, Internal Medicine Department, Bordeaux, France.,Univ Bordeaux, CNRS ImmunoConcEpT UMR 5164, Bordeaux, France
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X-linked immunodeficient (XID) mice exhibit high susceptibility to Cryptococcus gattii infection. Sci Rep 2021; 11:18397. [PMID: 34526536 PMCID: PMC8443669 DOI: 10.1038/s41598-021-97041-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2021] [Accepted: 08/19/2021] [Indexed: 12/12/2022] Open
Abstract
Cryptococcosis is an opportunistic disease caused by the fungus Cryptococcus neoformans and Cryptococcus gattii. It starts as a pulmonary infection that can spread to other organs, such as the brain, leading to the most serious occurrence of the disease, meningoencephalitis. The humoral response has already been described in limiting the progression of cryptococcosis where the B-1 cell seems to be responsible for producing natural IgM antibodies, crucial for combating fungal infections. The role of the B-1 cell in C. neoformans infection has been initially described, however the role of the humoral response of B-1 cells has not yet been evaluated during C. gattii infections. In the present study we tried to unravel this issue using XID mice, a murine model deficient in the Btk protein which compromises the development of B-1 lymphocytes. We use the XID mice compared to BALB/c mice that are sufficient for the B-1 population during C. gattii infection. Our model of chronic lung infection revealed that XID mice, unlike the sufficient group of B-1, had early mortality with significant weight loss, in addition to reduced levels of IgM and IgG specific to GXM isolated from the capsule of C. neoformans. In addition to this, we observed an increased fungal load in the blood and in the brain. We described an increase in the capsular size of C. gattii and the predominant presence of cytokines with a Th2 profile was also observed in these animals. Thus, the present study strongly points to a higher susceptibility of the XID mouse to C. gattii, which suggests that the presence of B-1 cells and anti-GXM antibodies is fundamental during the control of infection by C. gattii.
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Bhattarai K, Bhattarai K, Kabir ME, Bastola R, Baral B. Fungal natural products galaxy: Biochemistry and molecular genetics toward blockbuster drugs discovery. ADVANCES IN GENETICS 2021; 107:193-284. [PMID: 33641747 DOI: 10.1016/bs.adgen.2020.11.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
Secondary metabolites synthesized by fungi have become a precious source of inspiration for the design of novel drugs. Indeed, fungi are prolific producers of fascinating, diverse, structurally complex, and low-molecular-mass natural products with high therapeutic leads, such as novel antimicrobial compounds, anticancer compounds, immunosuppressive agents, among others. Given that these microorganisms possess the extraordinary capacity to secrete diverse chemical scaffolds, they have been highly exploited by the giant pharma companies to generate small molecules. This has been made possible because the isolation of metabolites from fungal natural sources is feasible and surpasses the organic synthesis of compounds, which otherwise remains a significant bottleneck in the drug discovery process. Here in this comprehensive review, we have discussed recent studies on different fungi (pathogenic, non-pathogenic, commensal, and endophytic/symbiotic) from different habitats (terrestrial and marines), the specialized metabolites they biosynthesize, and the drugs derived from these specialized metabolites. Moreover, we have unveiled the logic behind the biosynthesis of vital chemical scaffolds, such as NRPS, PKS, PKS-NRPS hybrid, RiPPS, terpenoids, indole alkaloids, and their genetic mechanisms. Besides, we have provided a glimpse of the concept behind mycotoxins, virulence factor, and host immune response based on fungal infections.
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Affiliation(s)
- Keshab Bhattarai
- Pharmaceutical Institute, Department of Pharmaceutical Biology, University of Tübingen, Tübingen, Germany
| | - Keshab Bhattarai
- Central Department of Chemistry, Tribhuvan University, Kirtipur, Kathmandu, Nepal
| | - Md Ehsanul Kabir
- Animal Health Research Division, Bangladesh Livestock Research Institute, Savar, Dhaka, Bangladesh
| | - Rina Bastola
- Spinal Cord Injury Association-Nepal (SCIAN), Pokhara, Nepal
| | - Bikash Baral
- Department of Biochemistry, University of Turku, Turku, Finland.
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Vaccination with Secreted Aspartyl Proteinase 2 Protein from Candida parapsilosis Can Enhance Survival of Mice during C. tropicalis-Mediated Systemic Candidiasis. Infect Immun 2020; 88:IAI.00312-20. [PMID: 32661125 DOI: 10.1128/iai.00312-20] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 07/09/2020] [Indexed: 12/21/2022] Open
Abstract
The rising incidence of non-albicans Candida species globally, along with the emergence of drug resistance, is a cause for concern. This study investigated the protective efficacy of secreted aspartyl proteinase 2 (Sap2) in systemic C. tropicalis infection. Vaccination with recombinant Sap2 (rSap2) protein from C. parapsilosis enhanced survival of mice compared to rSap2 vaccinations from C. albicans (P = 0.02), C. tropicalis (P = 0.06), and sham immunization (P = 0.04). Compared to sham-immunized mice, the fungal CFU number was significantly reduced in organs of Sap2-parapsilosis-immunized mice. Histopathologically, increased neutrophilic recruitment was observed in Sap2-parapsilosis- and Sap2-tropicalis-immunized mice. Among different rSap2 proteins, Sap2-parapsilosis vaccination induced increased titers of Sap2-specific Ig, IgG, and IgM antibodies, which could bind whole fungus. Between different groups, sera from Sap2-parapsilosis-vaccinated mice exhibited increased C. tropicalis biofilm inhibition ability in vitro and enhanced neutrophil-mediated fungal killing. Passive transfer of anti-Sap2-parapsilosis immune serum in naive mice significantly reduced fungal burdens compared to those in mice receiving anti-sham immune serum. Higher numbers of plasma cells and Candida-binding B cells in Sap2-vaccinated mice suggest a role of B cells during early stages of Sap2-mediated immune response. Additionally, increased levels of Th1/Th2/Th17 cytokines observed in Sap2-parapsilosis-vaccinated mice indicate immunomodulatory properties of Sap2. Epitope analysis performed using identified B-cell epitopes provides a basis to understand differences in immunogenicity observed among Sap2-antigens and can aid the development of a multivalent or multiepitope anti-Candida vaccine(s). In summary, our results suggest that Sap2-parapsilosis vaccination can improve mouse survival during C. tropicalis infection by inducing both humoral and cellular immunity, and higher titers of Sap2-induced antibodies are beneficial during systemic candidiasis.
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11
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Human IgM Inhibits the Formation of Titan-Like Cells in Cryptococcus neoformans. Infect Immun 2020; 88:IAI.00046-20. [PMID: 31988178 DOI: 10.1128/iai.00046-20] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Accepted: 01/22/2020] [Indexed: 02/07/2023] Open
Abstract
Human studies have shown associations between cryptococcal meningitis and reduced IgM memory B cell levels, and studies in IgM- and/or B cell-deficient mice have demonstrated increased Cryptococcus neoformans dissemination from lungs to brain. Since immunoglobulins are part of the immune milieu that C. neoformans confronts in a human host, and its ability to form titan cells is an important virulence mechanism, we determined the effect of human immunoglobulins on C. neoformans titan cell formation in vitro (i) Fluorescence microscopy showed normal human IgG and IgM bind C. neoformans (ii) C. neoformans grown in titan cell-inducing medium with IgM, not IgG, inhibited titan-like cell formation. (iii) Absorption of IgM with laminarin or curdlan (branched and linear 1-3-beta-d-glucans, respectively) decreased this effect. (iv) Transmission electron microscopy revealed that cells grown with IgM had small capsules and unique features not seen with cells grown with IgG. (v) Comparative transcriptional analysis of cell wall, capsule, and stress response genes showed that C. neoformans grown with IgM, not IgG or phosphate-buffered saline (PBS), had decreased expression of chitin synthetase, CHS1, CHS2, and CHS8, and genes encoding cell wall carbohydrate synthetases α-1-3-glucan (AGS1) and β-1,3-glucan (FKS1). IgM also decreased expression of RIM101 and HOG1, genes encoding central regulators of C. neoformans stress response pathways and cell morphogenesis. Our data show human IgM affects C. neoformans morphology in vitro and suggest that the hypothesis that human immunoglobulins may affect C. neoformans virulence in vivo warrants further investigation.
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Guess TE, Rosen J, Castro-Lopez N, Wormley FL, McClelland EE. An inherent T cell deficit in healthy males to C. neoformans infection may begin to explain the sex susceptibility in incidence of cryptococcosis. Biol Sex Differ 2019; 10:44. [PMID: 31477151 PMCID: PMC6720413 DOI: 10.1186/s13293-019-0258-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Accepted: 08/16/2019] [Indexed: 02/07/2023] Open
Abstract
Background Cryptococcus neoformans, the causative agent of cryptococcosis, causes ~ 181,000 deaths annually, with males having a higher incidence of disease than females (7M:3F). The reason for this sex bias remains unclear. We hypothesized that this disparity was due to biological differences between the male and female immune response. Methods Peripheral blood mononuclear cells (PBMCs) from healthy donors were isolated and infected with C. neoformans ± exogenous testosterone or 17-β-estradiol. C. neoformans, B, T, and NK cell proliferation was quantified by flow cytometry. Cytokine analysis was conducted via protein array or ELISA. Serological testing was conducted to determine previous exposure to C. neoformans. Results C. neoformans proliferated more in male PBMCs. T cell percentages in both sexes were lower in infected versus uninfected cells. Male PBMCs had lower CD3+, CD4+, and CD8+ T cells percentages during infection compared to females. Cytokine profiles showed differences in uninfected male and female PBMCs, which subsided during infection. Only one donor was sero-negative for prior C. neoformans exposure. There was an effect of estrogen in one dataset. Conclusions These results suggest that males show an inherent deficit in T cell response during infection, which may contribute to the increased incidence of disease in males. Electronic supplementary material The online version of this article (10.1186/s13293-019-0258-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Tiffany E Guess
- Department of Biology, Middle Tennessee State University, Murfreesboro, TN, USA
| | - Joseph Rosen
- Department of Biology, Middle Tennessee State University, Murfreesboro, TN, USA
| | - Natalia Castro-Lopez
- Department of Biology, The University of Texas at San Antonio, San Antonio, TX, USA.,South Texas Center for Emerging Infectious Diseases, The University of Texas at San Antonio, San Antonio, TX, USA
| | - Floyd L Wormley
- Department of Biology, The University of Texas at San Antonio, San Antonio, TX, USA.,South Texas Center for Emerging Infectious Diseases, The University of Texas at San Antonio, San Antonio, TX, USA
| | - Erin E McClelland
- Department of Biology, Middle Tennessee State University, Murfreesboro, TN, USA.
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Trevijano-Contador N, Pirofski L. Antibody immunity and natural resistance to cryptococcosis. CURRENT TROPICAL MEDICINE REPORTS 2019; 6:50-54. [PMID: 31134140 DOI: 10.1007/s40475-019-00174-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The encapsulated fungus Cryptococcus neoformans (Cn) causes cryptococcal meningitis (CM). There are ~180,000 deaths per year worldwide attributed to CM, which is the most common cause of meningitis in adults with HIV in sub-Saharan Africa. HIV infection with advanced immunodeficiency is the most important predisposing risk factor for CM, highlighting the critical role that T cell mediated immunity plays in disease prevention. Numerous studies in the past decade demonstrate that antibody immunity also plays a role in resistance to CM, although its role has taken more time to establish. In mice, B cells reduce early dissemination from lungs to brain, and naïve mouse IgM can enhance fungal containment in the lungs. In concert with these findings, human studies show that patients with CM have lower IgM memory B cell levels and/or different serological profiles than controls. In this article, we review recent data on the role that B cells and/or antibody-based immunity play in host defense against Cn and natural resistance to CM.
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Affiliation(s)
- N Trevijano-Contador
- Division of Infectious Diseases, Department of Medicine, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461, USA
| | - L Pirofski
- Division of Infectious Diseases, Department of Medicine, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461, USA.,Department of Microbiology & Immunology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461, USA.poly
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Yoon HA, Nakouzi A, Chang CC, Kuniholm MH, Carreño LJ, Wang T, Ndung’u T, Lewin SR, French MA, Pirofski LA. Association Between Plasma Antibody Responses and Risk for Cryptococcus-Associated Immune Reconstitution Inflammatory Syndrome. J Infect Dis 2019; 219:420-428. [PMID: 30010905 PMCID: PMC6325352 DOI: 10.1093/infdis/jiy447] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Accepted: 07/13/2018] [Indexed: 01/12/2023] Open
Abstract
Background Initiation of antiretroviral therapy (ART) in human immunodeficiency virus (HIV)-infected individuals with cryptococcal meningitis places them at risk for Cryptococcus-associated immune reconstitution inflammatory syndrome (C-IRIS). The relationship between antibody immunity and C-IRIS risk has not been investigated. Methods We compared plasma levels of immunoglobulins, C. neoformans glucuronoxylomannan (GXM) capsule-specific and laminarin (Lam)-binding IgM and IgG, and percentages of peripheral blood total and memory B cells between 27 HIV-infected patients with CM who developed C-IRIS and 63 who did not, and evaluated associations of these parameters with risk of C-IRIS. Results Prior to initiation of ART, plasma IgM, Lam-binding IgM (Lam-IgM), Lam-IgG, and GXM-IgM levels were significantly lower in patients who developed C-IRIS than those who did not. Multivariate analysis revealed significant inverse associations between C-IRIS and IgM (P = .0003), Lam-IgM (P = .0005), Lam-IgG (P = .002), and GXM-IgM (P = .002) independent of age, sex, HIV viral load, CD4+ T-cell count, and cerebrospinal fluid fungal burden. There were no associations between C-IRIS and total or memory B cells. Discussion Antibody profiles that include plasma IgM, Lam-IgM, Lam-IgG, and/or GXM-IgM may have value in furthering our understanding of C-IRIS pathogenesis and hold promise as candidate biomarkers of C-IRIS risk.
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Affiliation(s)
- Hyun Ah Yoon
- Department of Medicine, Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, New York
| | - Antonio Nakouzi
- Department of Microbiology and Immunology, Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, New York
| | - Christina C Chang
- Department of Infectious Diseases, Alfred Hospital and Monash University, Melbourne, Australia
| | - Mark H Kuniholm
- Department of Epidemiology and Biostatistics, University at Albany, Rensselaer, New York
| | - Leandro J Carreño
- Millennium Institute on Immunology and Immunotherapy, Programa de Inmunología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Tao Wang
- Department of Epidemiology and Population Health, Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, New York
| | - Thumbi Ndung’u
- HIV Pathogenesis Programme, Doris Duke Medical Research Institute, Nelson R Mandela School of Medicine, University of KwaZulu-Natal
- Africa Health Research Institute, Durban, South Africa
- Ragon Institute of Massachusetts General Hospital, Massachusetts Institute of Technology and Harvard University, Cambridge
- Max Planck Institute for Infection Biology, Berlin, Germany
| | - Sharon R Lewin
- Department of Infectious Diseases, Alfred Hospital and Monash University, Melbourne, Australia
- The Peter Doherty Institute for Infection and Immunity, University of Melbourne and Royal Melbourne Hospital
| | - Martyn A French
- University of Western Australia Medical School and School of Biomedical Sciences, Perth, Australia
| | - Liise-anne Pirofski
- Department of Medicine, Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, New York
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Hlupeni A, Nakouzi A, Wang T, Boyd KF, Makadzange TA, Ndhlovu CE, Pirofski LA. Antibody Responses in HIV-Infected Patients With Advanced Immunosuppression and Asymptomatic Cryptococcal Antigenemia. Open Forum Infect Dis 2018; 6:ofy333. [PMID: 30648127 PMCID: PMC6329905 DOI: 10.1093/ofid/ofy333] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Accepted: 12/06/2018] [Indexed: 12/11/2022] Open
Abstract
Background There are no host biomarkers of risk for HIV-associated cryptococcal meningitis (CM) except CD4+ T-cell deficiency. At present, serum cryptococcal antigen (CrAg) screening of those with CD4 <100 cells/µL is used to identify persons at risk for HIV-associated CM. We determined if plasma antibody profiles could discriminate CrAg+ from CrAg- patients. Methods We performed serological analyses of 237 HIV-infected asymptomatic Zimbabwean patients with CD4 <100 cells/µL; 125 CrAg- and CrAg+ but cerebrospinal fluid CrAg- by CrAg lateral flow assay. We measured plasma immunoglobulin M (IgM), immunoglobulin G (IgG) 1, and IgG2 concentrations by Luminex, and titers of Cryptococcus neoformans (Cn) glucuronoxylomannan (GXM) polysaccharide and naturally occurring Laminarin (natural Lam, a β-(1–3)-glucan linked polysaccharide)-binding IgM and IgG by enzyme-linked immunosorbent assay. Results GXM-IgG, -IgM, and -IgG2 levels were significantly higher in CrAg+ patients, whereas natural Lam-IgM and Lam-IgG were higher in CrAg- patients before and after adjustment for age, sex, and CD4 T-cell count, despite overlap of values. To address this variability and better discriminate the groups, we used Akaike Information Criteria to select variables that independently predicted CrAg+ status and included them in a receiver operating characteristic curve to predict CrAg status. By inclusion of CD4, GXM-IgG, GXM-IgM, and Lam-IgG, -IgG2, and -IgM, this model had an 80.4% probability (95% confidence interval, 0.75–0.86) of predicting CrAg+ status. Conclusions Statistical models that include multiple serological variables may improve the identification of patients at risk for CM and inform new directions in research on the complex role that antibodies may play in resistance and susceptibility to CM.
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Affiliation(s)
- Admire Hlupeni
- Department of Medicine, University of Zimbabwe College of Health Sciences, Harare, Zimbabwe
| | - Antonio Nakouzi
- Division of Infectious Diseases, Department of Medicine, Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, New York
| | - Tao Wang
- Department of Epidemiology and Biostatistics, Albert Einstein College of Medicine, Bronx, New York
| | - Kathryn F Boyd
- Department of Medicine, University of Zimbabwe College of Health Sciences, Harare, Zimbabwe
| | - Tariro A Makadzange
- Department of Medicine, University of Zimbabwe College of Health Sciences, Harare, Zimbabwe
| | - Chiratidzo E Ndhlovu
- Department of Medicine, University of Zimbabwe College of Health Sciences, Harare, Zimbabwe
| | - Liise-Anne Pirofski
- Division of Infectious Diseases, Department of Medicine, Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, New York.,Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York
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16
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Elsegeiny W, Marr KA, Williamson PR. Immunology of Cryptococcal Infections: Developing a Rational Approach to Patient Therapy. Front Immunol 2018; 9:651. [PMID: 29670625 PMCID: PMC5893745 DOI: 10.3389/fimmu.2018.00651] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Accepted: 03/16/2018] [Indexed: 12/13/2022] Open
Abstract
Cryptococcal meningoencephalitis is responsible for upwards of 15% of HIV-related deaths worldwide and is currently the most common cause of non-viral meningitis in the US, affecting both previously healthy and people with immune suppression caused by cancer chemotherapy, transplantation, and biologic therapies. Despite a continued 30-50% attributable mortality, recommended therapeutic strategies have remained largely unchanged since the 1950s. Recent murine models and human studies examining the role of the immune system in both susceptibility to the infection as well as host damage have begun to influence patient care decisions. The Damage Framework Response, originally proposed in 1999, was recently used to discuss dichotomous etiologies of host damage in cryptococcal disease. These include patients suffering microbiological damage with low host immunity (especially those immunosuppressed with HIV) and those having low (live) microbiological burden but high immune-mediated damage (HIV-related immune reconstitution syndrome and non-HIV-related postinfectious inflammatory response syndrome). Cryptococcal disease in previously healthy hosts, albeit rare, has been known for a long time. Immunophenotyping and dendritic cell-T cell signaling studies on cerebral spinal fluid of these rare patients reveal immune capacity for recognition and T-cell activation pathways including increased levels of HLA-DR and CD56. However, despite effective T-cell signals, brain biopsy and autopsy specimens demonstrated an M2 alternative macrophage polarization and poor phagocytosis of fungal cells. These studies expand the paradigm for cryptococcal disease susceptibility to include a prominent role for immune-mediated damage and suggest a need for careful individual consideration of immune activation during therapy of cryptococcal disease in diverse hosts.
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Affiliation(s)
- Waleed Elsegeiny
- Laboratory of Clinical Immunology and Microbiology (LCIM), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Bethesda, MD, United States
| | | | - Peter R. Williamson
- Laboratory of Clinical Immunology and Microbiology (LCIM), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Bethesda, MD, United States
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17
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Dutra FF, Albuquerque PC, Rodrigues ML, Fonseca FL. Warfare and defense: The host response to Cryptococcus infection. FUNGAL BIOL REV 2018. [DOI: 10.1016/j.fbr.2017.09.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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18
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Affiliation(s)
- Michael J Davis
- a From the Laboratory of Clinical Immunology and Microbiology, National Allergy & Infectious Diseases (NIAID) , National Institutes of Health (NIH ), Bethesda , Maryland , USA
| | - Michail S Lionakis
- a From the Laboratory of Clinical Immunology and Microbiology, National Allergy & Infectious Diseases (NIAID) , National Institutes of Health (NIH ), Bethesda , Maryland , USA
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19
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Rohatgi S, Nakouzi A, Carreño LJ, Slosar-Cheah M, Kuniholm MH, Wang T, Pappas PG, Pirofski LA. Antibody and B Cell Subset Perturbations in Human Immunodeficiency Virus-Uninfected Patients With Cryptococcosis. Open Forum Infect Dis 2017; 5:ofx255. [PMID: 29354657 PMCID: PMC5767948 DOI: 10.1093/ofid/ofx255] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Accepted: 11/16/2017] [Indexed: 12/18/2022] Open
Abstract
The importance of antibody immunity in protection against Cryptococcus neoformans remains unresolved. We measured serum C neoformans-specific and total antibody levels and peripheral blood B cell subsets of 12 previously healthy patients with cryptococcosis (cases) and 21 controls. Before and after adjustment for age, sex, and race, cryptococcal capsular polysaccharide immunoglobulin G was higher in cases than controls, whereas total B and memory B cell levels were lower. These associations parallel previous findings in patients with human immunodeficiency virus-associated cryptococcosis and suggest that B cell subset perturbations may also associate with disease in previously normal individuals with cryptococcosis.
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Affiliation(s)
- Soma Rohatgi
- Department of Biotechnology, IIT-Roorkee, Uttarakhand, India
| | - Antonio Nakouzi
- Division of Infectious Diseases, Department of Medicine, Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, New York
| | - Leandro J Carreño
- Millennium Institute on Immunology and Immunotherapy, Programa de Inmunología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago
| | | | - Mark H Kuniholm
- Department of Epidemiology and Biostatistics, University at Albany, State University of New York, Rensselaer, New York
| | - Tao Wang
- Department of Epidemiology and Population Health, Albert Einstein College of Medicine, Bronx, New York
| | - Peter G Pappas
- Division of Infectious Diseases, University of Alabama at Birmingham
| | - Liise-Anne Pirofski
- Division of Infectious Diseases, Department of Medicine, Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, New York.,Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York
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20
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Dufaud C, Rivera J, Rohatgi S, Pirofski LA. Naïve B cells reduce fungal dissemination in Cryptococcus neoformans infected Rag1 -/- mice. Virulence 2017; 9:173-184. [PMID: 28837391 PMCID: PMC5955176 DOI: 10.1080/21505594.2017.1370529] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
IgM and B-1 cell deficient mice exhibit early C. neoformans dissemination from lungs to brain, but a definitive role for B cells in conferring resistance to C. neoformans dissemination has not been established. To address this question, we developed an intranasal (i.n.) C. neoformans infection model in B and T cell deficient Rag1-/- mice and found they also exhibit earlier fungal dissemination and higher brain CFU than wild-type C57Bl/6 (wild-type) mice. To probe the effect of B cells on fungal dissemination, Rag1-/- mice were given splenic (intravenously) or peritoneal (intraperitoneally) B cells from wild-type mice and infected i.n. with C. neoformans 7 d later. Mice that received B cells had lung histopathology resembling wild type mice 14 d post-infection, and B-1, not B-2 or T cells in their lungs, and serum and lung IgM and IgG 21 d post-infection. Lung CFU were comparable in wild-type, Rag1-/-, and Rag1-/- mice that received B cells 21 d post-infection, but brain CFU were significantly lower in mice that received B cells than Rag1-/- mice that did not. To determine if natural antibody can promote immunity in our model, we measured alveolar macrophage phagocytosis of C. neoformans in Rag1-/- mice treated with naive wild-type IgM-sufficient or sIgM-/- IgM-deficient sera before infection. Compared to IgM-deficient sera, IgM-sufficient sera significantly increased phagocytosis. Our data establish B cells are able to reduce early C. neoformans dissemination in mice and suggest natural IgM may be a key mediator of early antifungal immunity in the lungs.
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Affiliation(s)
- Chad Dufaud
- a Department of Immunology and Microbial Sciences , Scripps Research Institute , La Jolla , CA , USA
| | - Johanna Rivera
- b Division of Infectious Diseases , Albert Einstein College of Medicine and Montefiore Medical Center , Bronx , NY , USA
| | - Soma Rohatgi
- c Department of Biotechnology IIT-Roorkee , Uttarakhand , India
| | - Liise-Anne Pirofski
- a Department of Immunology and Microbial Sciences , Scripps Research Institute , La Jolla , CA , USA.,d Department of Microbiology and Immunology , Albert Einstein College of Medicine , Bronx , NY , USA
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21
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Abstract
Cryptococcus species are encapsulated fungi found in the environment that predominantly cause disease in immunocompromised hosts after inhalation into the lungs. Even with contemporary antifungal regimens, patients with cryptococcosis continue to have high morbidity and mortality rates. The development of more effective therapies may depend on our understanding of the cellular and molecular mechanisms by which the host promotes sterilizing immunity against the fungus. This review will highlight our current knowledge of how Cryptococcus, primarily the species C. neoformans, is sensed by the mammalian host and how subsequent signaling pathways direct the anti-cryptococcal response by effector cells of the innate immune system.
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Affiliation(s)
- Lena J Heung
- Infectious Diseases Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
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22
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Okamoto K, Proia LA, Demarais PL. Disseminated Cryptococcal Disease in a Patient with Chronic Lymphocytic Leukemia on Ibrutinib. Case Rep Infect Dis 2016; 2016:4642831. [PMID: 27703818 PMCID: PMC5039271 DOI: 10.1155/2016/4642831] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Accepted: 08/28/2016] [Indexed: 01/08/2023] Open
Abstract
Cryptococcus is a unique environmental fungus that can cause disease most often in immunocompromised individuals with defective cell-mediated immunity. Chronic lymphocytic leukemia (CLL) is not known to be a risk factor for cryptococcal disease although cases have been described mainly in patients treated with agents that suppress cell-mediated immunity. Ibrutinib is a new biologic agent used for treatment of CLL, mantle cell lymphoma, and Waldenstrom's macroglobulinemia. It acts by inhibiting Bruton's tyrosine kinase, a kinase downstream of the B-cell receptor critical for B-cell survival and proliferation. Ibrutinib use has not been associated previously with cryptococcal disease. However, recent evidence suggested that treatments aimed at blocking the function of Bruton's tyrosine kinase could pose a higher risk for cryptococcal infection in a mice model. Here, we report the first case of disseminated cryptococcal disease in a patient with CLL treated with ibrutinib. When evaluating possible infection in CLL patients receiving ibrutinib, cryptococcal disease, which could be life threatening if overlooked, could be considered.
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Affiliation(s)
- Koh Okamoto
- Division of Infectious Diseases, John H. Stroger Jr. Hospital of Cook County, Chicago, IL, USA
- Division of Infectious Diseases, Rush University Medical Center, Chicago, IL, USA
| | - Laurie A. Proia
- Division of Infectious Diseases, John H. Stroger Jr. Hospital of Cook County, Chicago, IL, USA
| | - Patricia L. Demarais
- Division of Infectious Diseases, Rush University Medical Center, Chicago, IL, USA
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23
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Abstract
Fungal diseases are major causes of morbidity and mortality among the immunocompromised, including HIV-infected individuals and patients with cancer. Individuals without a weakened immune system can also suffer from these infections. Not surprisingly, fungi are a major target for the immune system, rendered visible to it by expression of pathogen-associated molecular patterns/signatures. We now appreciate the roles of both innate and adaptive immunity in eliminating fungal infections, and how a disproportionate or inadequate immune response can diminish the host's capacity to eliminate fungi. This review focuses on our current understanding of the roles of innate and adaptive immunity in clearing common and emergent fungal pathogens. A clearer understanding of how the host's immune response tackles fungal infection may provide useful clues as to how we might develop new agents to treat those diseases in the future.
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Affiliation(s)
- Shuai Jiang
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
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24
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Cryptococcemia in an Elderly Woman with Retroperitoneal Diffuse Large B-cell Lymphoma after Rituximab-containing Chemotherapy. INT J GERONTOL 2016. [DOI: 10.1016/j.ijge.2015.02.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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25
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Innate host defenses against Cryptococcus neoformans. J Microbiol 2016; 54:202-11. [PMID: 26920880 DOI: 10.1007/s12275-016-5625-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Revised: 01/11/2016] [Accepted: 01/11/2016] [Indexed: 12/21/2022]
Abstract
Cryptococcus neoformans, the predominant etiological agent of cryptococcosis, can cause life-threatening infections of the central nervous system in immunocompromised and immunocompetent individuals. Cryptococcal meningoencephalitis is the most common disseminated fungal infection in AIDS patients, and remains the third most common invasive fungal infection among organ transplant recipients. The administration of highly active antiretroviral therapy (HAART) has resulted in a decrease in the number of cases of AIDS-related cryptococcosis in developed countries, but in developing countries where HAART is not readily available, Cryptococcus is still a major concern. Therefore, there is an urgent need for the development of novel therapies and/or vaccines to combat cryptococcosis. Understanding the protective immune responses against Cryptococcus is critical for development of vaccines and immunotherapies to combat cryptococcosis. Consequently, this review focuses on our current knowledge of protective immune responses to C. neoformans, with an emphasis on innate immune responses.
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26
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Kanayama M, Shinohara ML. Roles of Autophagy and Autophagy-Related Proteins in Antifungal Immunity. Front Immunol 2016; 7:47. [PMID: 26925060 PMCID: PMC4757664 DOI: 10.3389/fimmu.2016.00047] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Accepted: 01/31/2016] [Indexed: 12/21/2022] Open
Abstract
Autophagy was initially characterized as a process to digest cellular components, including damaged cell organelles or unused proteins. However, later studies showed that autophagy plays an important role to protect hosts from microbial infections. Accumulating evidences showed the contribution of autophagy itself and autophagy-related proteins (ATGs) in the clearance of bacteria, virus, and parasites. A number of studies also revealed the molecular mechanisms by which autophagy is initiated and developed. Furthermore, it is now understood that some ATGs are shared between two distinct processes; autophagy and LC3-associated phagocytosis (LAP). Thus, our understanding on autophagy has been greatly enhanced in the last decade. By contrast, roles of autophagy and ATGs in fungal infections are still elusive relative to those in bacterial and viral infections. Based on limited numbers of reports, ATG-mediated host responses appear to significantly vary depending on invading fungal species. In this review, we discuss how autophagy and ATGs are involved in antifungal immune responses based on recent discoveries.
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Affiliation(s)
- Masashi Kanayama
- Department of Immunology, Duke University School of Medicine , Durham, NC , USA
| | - Mari L Shinohara
- Department of Immunology, Duke University School of Medicine, Durham, NC, USA; Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC, USA
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27
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Abstract
Cryptococcosis is caused by the fungal genus Cryptococcus. Cryptococcosis, predominantly meningoencephalitis, emerged with the HIV pandemic, primarily afflicting HIV-infected patients with profound T-cell deficiency. Where in use, combination antiretroviral therapy has markedly reduced the incidence of and risk for disease, but cryptococcosis continues to afflict those without access to therapy, particularly in sub-Saharan Africa and Asia. However, cryptococcosis also occurs in solid organ transplant recipients and patients with other immunodeficiencies as well as those with no known immunodeficiency. This article reviews innate and adaptive immune responses to C. neoformans, with an emphasis on recent studies on the role of B cells, natural IgM and Fc gamma receptor polymorphisms in resistance to cryptococcosis.
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Affiliation(s)
- Soma Rohatgi
- Division of Infectious Diseases, Department of Medicine, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461, USA
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28
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Martinez LR. Commentary: Role of Sterylglucosidase 1 (Sgl1) on the pathogenicity of Cryptococcus neoformans: potential applications for vaccine development. Front Microbiol 2015; 6:1112. [PMID: 26500643 PMCID: PMC4599045 DOI: 10.3389/fmicb.2015.01112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Accepted: 09/25/2015] [Indexed: 11/16/2022] Open
Affiliation(s)
- Luis R Martinez
- Department of Biomedical Sciences, New York Institute of Technology College of Osteopathic Medicine, New York Institute of Technology Old Westbury, NY, USA
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29
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Datta K, Subramaniam KS. Host Defense Against Cryptococcal Disease: Is There a Role for B Cells and Antibody-Mediated Immunity? CURRENT FUNGAL INFECTION REPORTS 2014. [DOI: 10.1007/s12281-014-0208-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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30
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Murdock BJ, Teitz-Tennenbaum S, Chen GH, Dils AJ, Malachowski AN, Curtis JL, Olszewski MA, Osterholzer JJ. Early or late IL-10 blockade enhances Th1 and Th17 effector responses and promotes fungal clearance in mice with cryptococcal lung infection. THE JOURNAL OF IMMUNOLOGY 2014; 193:4107-16. [PMID: 25225664 DOI: 10.4049/jimmunol.1400650] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The potent immunoregulatory properties of IL-10 can counteract protective immune responses and, thereby, promote persistent infections, as evidenced by studies of cryptococcal lung infection in IL-10-deficient mice. To further investigate how IL-10 impairs fungal clearance, the current study used an established murine model of C57BL/6J mice infected with Cryptococcus neoformans strain 52D. Our results demonstrate that fungal persistence is associated with an early and sustained expression of IL-10 by lung leukocytes. To examine whether IL-10-mediated immune modulation occurs during the early or late phase of infection, assessments of fungal burden and immunophenotyping were performed on mice treated with anti-IL-10R-blocking Ab at 3, 6, and 9 d postinfection (dpi) (early phase) or at 15, 18, and 21 dpi (late phase). We found that both early and late IL-10 blockade significantly improved fungal clearance within the lung compared with isotype control treatment when assessed 35 dpi. Immunophenotyping identified that IL-10 blockade enhanced several critical effector mechanisms, including increased accumulation of CD4(+) T cells and B cells, but not CD8(+) T cells; specific increases in the total numbers of Th1 and Th17 cells; and increased accumulation and activation of CD11b(+) dendritic cells and exudate macrophages. Importantly, IL-10 blockade effectively abrogated dissemination of C. neoformans to the brain. Collectively, this study identifies early and late cellular and molecular mechanisms through which IL-10 impairs fungal clearance and highlights the therapeutic potential of IL-10 blockade in the treatment of fungal lung infections.
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Affiliation(s)
- Benjamin J Murdock
- Research Service, Veterans Affairs Ann Arbor Healthcare System, Department of Veterans Affairs Health System, Ann Arbor, MI 48105; Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Health System, Ann Arbor, MI 48109
| | - Seagal Teitz-Tennenbaum
- Research Service, Veterans Affairs Ann Arbor Healthcare System, Department of Veterans Affairs Health System, Ann Arbor, MI 48105; Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Health System, Ann Arbor, MI 48109
| | - Gwo-Hsiao Chen
- Research Service, Veterans Affairs Ann Arbor Healthcare System, Department of Veterans Affairs Health System, Ann Arbor, MI 48105; Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Health System, Ann Arbor, MI 48109
| | - Anthony J Dils
- Research Service, Veterans Affairs Ann Arbor Healthcare System, Department of Veterans Affairs Health System, Ann Arbor, MI 48105; Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Health System, Ann Arbor, MI 48109
| | - Antoni N Malachowski
- Research Service, Veterans Affairs Ann Arbor Healthcare System, Department of Veterans Affairs Health System, Ann Arbor, MI 48105; Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Health System, Ann Arbor, MI 48109
| | - Jeffrey L Curtis
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Health System, Ann Arbor, MI 48109; Pulmonary Section, Medical Service, Veterans Affairs Ann Arbor Healthcare System, Department of Veterans Affairs Health System, Ann Arbor, MI 48105; and Graduate Program in Immunology, University of Michigan Health System, Ann Arbor, MI 48109
| | - Michal A Olszewski
- Research Service, Veterans Affairs Ann Arbor Healthcare System, Department of Veterans Affairs Health System, Ann Arbor, MI 48105; Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Health System, Ann Arbor, MI 48109; Graduate Program in Immunology, University of Michigan Health System, Ann Arbor, MI 48109
| | - John J Osterholzer
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Health System, Ann Arbor, MI 48109; Pulmonary Section, Medical Service, Veterans Affairs Ann Arbor Healthcare System, Department of Veterans Affairs Health System, Ann Arbor, MI 48105; and Graduate Program in Immunology, University of Michigan Health System, Ann Arbor, MI 48109
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Armstrong-James D, Meintjes G, Brown GD. A neglected epidemic: fungal infections in HIV/AIDS. Trends Microbiol 2014; 22:120-7. [PMID: 24530175 DOI: 10.1016/j.tim.2014.01.001] [Citation(s) in RCA: 219] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Revised: 01/02/2014] [Accepted: 01/08/2014] [Indexed: 11/17/2022]
Abstract
Invasive fungal infections (IFIs) are a major cause of HIV-related mortality globally. Despite widespread rollout of combined antiretroviral therapy, there are still up to 1 million deaths annually from IFIs, accounting for 50% of all AIDS-related death. A historic failure to focus efforts on the IFIs that kill so many HIV patients has led to fundamental flaws in the management of advanced HIV infection. This review, based on the EMBO AIDS-Related Mycoses Workshop in Cape Town in July 2013, summarizes the current state of the-art in AIDS-related mycoses, and the key action points required to improve outcomes from these devastating infections.
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Affiliation(s)
- Darius Armstrong-James
- Imperial Fungal Diseases Group, Imperial College London, Department of Infectious Diseases and Immunity, Hammersmith Hospital, Du Cane Road, London W12 0NN, UK.
| | - Graeme Meintjes
- Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Observatory, 7925 Cape Town, South Africa
| | - Gordon D Brown
- Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Observatory, 7925 Cape Town, South Africa; Aberdeen Fungal Group, University of Aberdeen, Institute of Medical Sciences, Foresterhill, Aberdeen AB25 2ZD, UK
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Toward identification of the genetic risk profile for cryptococcal disease in HIV-infected patients. mBio 2013; 4:e00798-13. [PMID: 24129259 PMCID: PMC3812711 DOI: 10.1128/mbio.00798-13] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Cryptococcus spp. are important fungal pathogens that represent a major cause of morbidity and mortality in both immunocompetent and immunodeficient patients. Although cryptococcal disease is one of the major causes of death in HIV-infected patients, especially in sub-Saharan Africa, not all patients at risk with low CD4 counts develop the disease. It has been thus hypothesized that host genetic variation may represent an important susceptibility risk factor for this infection. In their recent study in mBio, Rohatgi et al. [S. Rohatgi et al., mBio 4(5):e00573-13, 2013, doi:10.1128/mBio.00573-13] present an important piece of evidence to support this hypothesis, by demonstrating that the FCGR3A 158 F/V polymorphism has an important impact on susceptibility to cryptococcal disease in HIV-infected patients. The authors present both genetic evidence and immunological validation for the hypothesis that humoral immunity in general and FCGR3A-mediated uptake and antibody-dependent cellular cytotoxicity (ADCC) in particular play important roles in the pathogenesis of Cryptococcus infection. Their discovery that the 158V allele of this polymorphism can increase the risk of Cryptococcus infections up to 20-fold in homozygous individuals opens the possibility for risk stratification and personalized treatment of HIV-infected patients.
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Abstract
Cryptococcus neoformans is one of the most common causes of fungal disease in HIV-infected persons, but not all of those who are infected develop cryptococcal disease (CD). Although CD4+ T cell deficiency is a risk factor for HIV-associated CD, polymorphisms of phagocytic Fc gamma receptors (FCGRs) have been linked to CD risk in HIV-uninfected persons. To investigate associations between FCGR2A 131 H/R and FCGR3A 158 F/V polymorphisms and CD risk in HIV-infected persons, we performed PCR-based genotyping on banked samples from 164 men enrolled in the Multicenter AIDS Cohort Study (MACS): 55 who were HIV infected and developed CD and a matched control group of 54 who were HIV infected and 55 who were HIV uninfected. Using additive and allelic statistical models for analysis, the high-affinity FCGR3A 158V allele was significantly associated with CD status after adjusting for race/ethnicity (odds ratio [OR], 2.1; P = 0.005), as was the FCGR3A 158 VV homozygous genotype after adjusting for race/ethnicity, rate of CD4+ T cell decline, and nadir CD4+ T cell count (OR, 21; P = 0.005). No associations between CD and FCGR2A 131 H/R polymorphism were identified. In binding studies, human IgG (hIgG)-C. neoformans complexes exhibited more binding to CHO-K1 cells expressing FCGR3A 158V than to those expressing FCGR3A 158F, and in cytotoxicity assays, natural killer (NK) cells expressing FCGR3A 158V induced more C. neoformans-infected monocyte cytotoxicity than those expressing FCGR3A 158F. Together, these results show an association between the FCGR3A 158V allele and risk for HIV-associated CD and suggest that this polymorphism could promote C. neoformans pathogenesis via increased binding of C. neoformans immune complexes, resulting in increased phagocyte cargo and/or immune activation. HIV-associated CD4+ T cell deficiency is a sine qua non for HIV-associated cryptococcal disease (CD), but not all patients with CD4+ T cell deficiency develop CD despite serological evidence of previous infection. At present, there are no biomarkers that predict HIV-associated CD risk. The goal of our study was to understand whether Fc gamma receptor (FCGR) polymorphisms that have been shown to portend CD risk in HIV-uninfected people are associated with CD risk in HIV-infected people. Such biomarkers could identify those who would benefit most from targeted prophylaxis and/or earlier treatment, particularly in sub-Saharan Africa, where there are nearly a million cases of HIV-associated CD annually. A biomarker of risk could also identify potential candidates for immunization, should there be a vaccine for Cryptococcus neoformans.
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X-linked immunodeficient mice exhibit enhanced susceptibility to Cryptococcus neoformans Infection. mBio 2013; 4:mBio.00265-13. [PMID: 23820392 PMCID: PMC3705448 DOI: 10.1128/mbio.00265-13] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Bruton’s tyrosine kinase (Btk) is a signaling molecule that plays important roles in B-1 B cell development and innate myeloid cell functions and has recently been identified as a target for therapy of B cell lymphomas. We examined the contribution of B-1 B cells to resistance to Cryptococcus neoformans infection by utilizing X-linked immunodeficient (XID) mice (CBA-CaHN-XID), which possess a mutation in Btk. XID mice had significantly higher brain fungal burdens than the controls 6 weeks after infection with C. neoformans strain 52D (CN52D); however, consistent with the propensity for greater virulence of C. neoformans strain H99 (CNH99), CNH99-infected XID mice had higher lung and brain fungal burdens than the controls 3 weeks after infection. Further studies in a chronic CN52D model revealed markedly lower levels of total and C. neoformans-specific serum IgM in XID mice than in the control mice 1 and 6 weeks after infection. Alveolar macrophage phagocytosis was markedly impaired in CN52D-infected XID mice compared to the controls, with XID mice exhibiting a disorganized lung inflammatory pattern in which Gomori silver staining revealed significantly more enlarged, extracellular C. neoformans cells than the controls. Adoptive transfer of B-1 B cells to XID mice restored peritoneal B-1 B cells but did not restore IgM levels to those of the controls and had no effect on the brain fungal burden at 6 weeks. Taken together, our data support the hypothesis that IgM promotes fungal containment in the lungs by enhancing C. neoformans phagocytosis and restricting C. neoformans enlargement. However, peritoneal B-1 B cells are insufficient to reconstitute a protective effect in the lungs. Cryptococcus neoformans is a fungal pathogen that causes an estimated 600,000 deaths per year. Most infections occur in individuals who are immunocompromised, with the majority of cases occurring in those with HIV/AIDS, but healthy individuals also develop disease. Immunoglobulin M (IgM) has been linked to resistance to disease in humans and mice. In this article, we found that X-linked immunodeficient (XID) mice, which have markedly reduced levels of IgM, were unable to contain Cryptococcus in the lungs. This was associated with reduced yeast uptake by macrophages, an aberrant tissue inflammatory response, an enlargement of the yeast cells in the lungs, and fungal dissemination to the brain. Since XID mice have a mutation in the Bruton’s tyrosine kinase (Btk) gene, our data suggest that treatments aimed at blocking the function of Btk could pose a higher risk for cryptococcosis.
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Iliev ID, Underhill DM. Striking a balance: fungal commensalism versus pathogenesis. Curr Opin Microbiol 2013; 16:366-73. [PMID: 23756050 DOI: 10.1016/j.mib.2013.05.004] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2013] [Revised: 05/09/2013] [Accepted: 05/13/2013] [Indexed: 02/06/2023]
Abstract
The environment is suffused with nearly countless types of fungi, and our immune systems must be tuned to cope with constant exposure to them. In addition, it is becoming increasingly clear that many surfaces of our bodies are colonized with complex populations of fungi (the mycobiome) in the same way that they are colonized with complex populations of bacteria. The immune system must tolerate colonization with commensal fungi but defend against fungal invasion. Truly life-threatening fungal infections are common only when this balance is disrupted through, for example, profound immunosuppression or genetic mutation. Recent studies have begun to shed light on how this balance is established and maintained, and suggest future studies on the role of fungi in homeostatic conditions.
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Affiliation(s)
- Iliyan D Iliev
- F. Widjaja Foundation Inflammatory Bowel and Immunobiology Research Institute, Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA.
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