1
|
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.
Collapse
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
| |
Collapse
|
2
|
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.
Collapse
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,
| |
Collapse
|
3
|
Yoon H, Nakouzi A, Pappas PG, Hemmige VS, Pirofski LA. Cryptococcus neoformans-specific and non- Cryptococcous neoformans-specific antibody profiles in organ transplant recipients with and without cryptococcosis. Open Forum Infect Dis 2022; 9:ofac211. [PMID: 35794949 PMCID: PMC9253883 DOI: 10.1093/ofid/ofac211] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 04/18/2022] [Indexed: 11/12/2022] Open
Abstract
Antibody immunity has not been studied in organ transplant recipients (OTRs) with cryptococcosis. We determined serum antibody levels in OTRs: 23 cryptococcosis cases and 21 controls. Glucuronoxylomannan immunoglobulin M (IgM) and laminarin IgM were lower in cases than controls, were inversely associated with cryptococcosis status, and may hold promise as markers of cryptococcosis.
Collapse
Affiliation(s)
- Hyunah Yoon
- Division of Infectious Diseases, Department of Medicine, Albert Einstein College of Medicine, Montefiore Medical Center, Bronx, New York, USA
| | - Antonio Nakouzi
- Division of Infectious Diseases, Department of Medicine, Albert Einstein College of Medicine, Montefiore Medical Center, Bronx, New York, USA
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Peter G Pappas
- Division of Infectious Diseases, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Vagish S Hemmige
- Division of Infectious Diseases, Department of Medicine, Albert Einstein College of Medicine, Montefiore Medical Center, Bronx, New York, USA
| | - Liise anne Pirofski
- Correspondence: Liise-anne Pirofski, MD, Division of Infectious Diseases, Department of Medicine, Albert Einstein College of Medicine, 1300 Morris Park Ave, Room 610, Belfer Bldg, Bronx, NY 10461, USA ()
| |
Collapse
|
4
|
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.
Collapse
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
| |
Collapse
|
5
|
Cryptococcosis in Liver Transplant Candidates and Recipients. CURRENT FUNGAL INFECTION REPORTS 2020. [DOI: 10.1007/s12281-020-00399-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
6
|
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.
Collapse
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.
| |
Collapse
|
7
|
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.
Collapse
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
| |
Collapse
|
8
|
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.
Collapse
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
| |
Collapse
|
9
|
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.
Collapse
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
| |
Collapse
|
10
|
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.
Collapse
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
| |
Collapse
|
11
|
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.
Collapse
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
| |
Collapse
|
12
|
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.
Collapse
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
| |
Collapse
|
13
|
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.
Collapse
Affiliation(s)
- Lena J Heung
- Infectious Diseases Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| |
Collapse
|
14
|
Aslanyan L, Ekhar VV, DeLeon-Rodriguez CM, Martinez LR. Capsular specific IgM enhances complement-mediated phagocytosis and killing of Cryptococcus neoformans by methamphetamine-treated J774.16 macrophage-like cells. Int Immunopharmacol 2017; 49:77-84. [PMID: 28551495 DOI: 10.1016/j.intimp.2017.05.024] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 05/16/2017] [Accepted: 05/19/2017] [Indexed: 12/29/2022]
Abstract
Methamphetamine (METH) is a powerful and highly addictive stimulant that affects the central nervous system of users in the United States and worldwide, and its consumption is associated to the acquisition of HIV and AIDS-related infections. METH enhances cryptococcosis in mice, an opportunistic infection caused by the encapsulated fungus Cryptococcus neoformans. Due to its ability to survive within macrophages, C. neoformans is an ideal model to study pathogen-macrophage interactions. METH abrogates normal macrophage function, which might contribute to the higher rate and more rapid progression of infections in drug abusers. Hence, we investigated the role of complement and specific IgM to C. neoformans capsular polysaccharide on the function of J774.16 macrophage-like cells after exposure to METH. We found that complement and IgM significantly promotes complement-mediated phagocytosis of C. neoformans by J774.16 cells in comparison to co-incubation with complement alone. IgM enhances the expression of complement receptor 3 on the surface macrophages treated with the drug. Also, IgM-increased macrophage phagocytosis of C. neoformans may be associated with upregulation of GTPase-RhoA, a key regulator of the actin polymerization signaling cascade. Fungal cells incubated with complement and IgM in the presence of METH demonstrated higher number of cells per aggregate, a possible explanation for their enhanced ingestion by phagocytes. IgM increased killing of yeast cells by macrophages by inhibiting the alkalization of the phagosome and stimulating the intracellular production of nitric oxide. Together, our findings suggest that IgM stimulates the effector functions of macrophages against opportunistic pathogens in the setting of drug abuse.
Collapse
Affiliation(s)
- Lilit Aslanyan
- Department of Biomedical Sciences, NYIT College of Osteopathic Medicine, New York Institute of Technology, Old Westbury, NY, United States
| | - Vaibhav V Ekhar
- Department of Biomedical Sciences, Long Island University-Post, Brookville, NY, United States
| | - Carlos M DeLeon-Rodriguez
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, United States
| | - Luis R Martinez
- Department of Biomedical Sciences, NYIT College of Osteopathic Medicine, New York Institute of Technology, Old Westbury, NY, United States; Department of Biomedical Sciences, Long Island University-Post, Brookville, NY, United States; Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, United States.
| |
Collapse
|
15
|
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.
Collapse
Affiliation(s)
- Soma Rohatgi
- Division of Infectious Diseases, Department of Medicine, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461, USA
| | | |
Collapse
|
16
|
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]
|
17
|
Casadevall A, Pirofski LA. Immunoglobulins in defense, pathogenesis, and therapy of fungal diseases. Cell Host Microbe 2012; 11:447-56. [PMID: 22607798 DOI: 10.1016/j.chom.2012.04.004] [Citation(s) in RCA: 115] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Only two decades ago antibodies to fungi were thought to have little or no role in protection against fungal diseases. However, subsequent research has provided convincing evidence that certain antibodies can modify the course of fungal infection to the benefit or detriment of the host. Hybridoma technology was the breakthrough that enabled the characterization of antibodies to fungi, illuminating some of the requirements for antibody efficacy. As discussed in this review, fungal-specific antibodies mediate protection through direct actions on fungal cells and through classical mechanisms such as phagocytosis and complement activation. Although mechanisms of antibody-mediated protection are often species-specific, numerous fungal antigens can be targeted to generate vaccines and therapeutic immunoglobulins. Furthermore, the study of antibody function against medically important fungi has provided fresh immunological insights into the complexity of humoral immunity that are likely to apply to other pathogens.
Collapse
Affiliation(s)
- Arturo Casadevall
- Department of Microbiology and Immunology and Medicine, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
| | | |
Collapse
|
18
|
Abstract
The interaction of pathogenic Cryptococcus species with their various hosts is somewhat unique compared to other fungal pathogens such as Aspergillus fumigatus and Candida albicans. Cryptococcus shares an intimate association with host immune cells, leading to enhanced intracellular growth. Furthermore, unlike most other fungal pathogens, the signs and symptoms of cryptococcal disease are typically self-inflicted by the host during the host's attempt to clear this invader from sensitive organ systems such as the central nervous system. In this review, we will summarize the story of host-Cryptococcus interactions to date and explore strategies to exploit the current knowledge for treatment of cryptococcal infections.
Collapse
Affiliation(s)
- Michael S Price
- Department of Medicine, Duke University Medical Center, Research Drive, Durham, NC 27710, USA
| | | |
Collapse
|
19
|
Subramaniam KS, Datta K, Quintero E, Manix C, Marks MS, Pirofski LA. The absence of serum IgM enhances the susceptibility of mice to pulmonary challenge with Cryptococcus neoformans. THE JOURNAL OF IMMUNOLOGY 2010; 184:5755-67. [PMID: 20404271 DOI: 10.4049/jimmunol.0901638] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The importance of T cell-mediated immunity for resistance to the disease (cryptococcal disease) caused by Cryptococcus neoformans is incontrovertible, but whether Ab immunity also contributes to resistance remains uncertain. To investigate the role of IgM in resistance to C. neoformans, we compared the survival, fungal burden, lung and brain inflammatory responses, and lung phagocytic response of sIgM(-/-) mice, which lack secreted IgM, to that of IgM sufficient C57BL6x129Sv (heretofore, control) mice at different times after intranasal infection with C. neoformans (24067). sIgM(-/-) mice had higher mortality and higher blood and brain CFUs 28 d postinfection, but lung CFUs were comparable. Lungs of control mice manifested exuberant histiocytic inflammation with visible C. neoformans, findings that were not observed in sIgM(-/-) mice, whereas in brain sections, sIgM(-/-) mice had marked inflammation with visible C. neoformans that was not observed in control mice. Cytokine responses were significant for higher levels of lung IL-1beta and IL-12 24 h postinfection in control mice and higher levels of lung and brain IL-17 28 d postinfection in sIgM(-/-) mice. Alveolar macrophage phagocytosis was significantly higher for control than for sIgM(-/-) mice 24 h postinfection; however, phagocytic indices of sIgM(-/-) mice increased after reconstitution of sIgM(-/-) mice with polyclonal IgM. These data establish a previously unrecognized role for IgM in resistance to intranasal infection with C. neoformans in mice and suggest that the mechanism by which it mediates a host benefit is by augmenting Th1 polarization, macrophage recruitment and phagocytosis of C. neoformans.
Collapse
Affiliation(s)
- Krishanthi S Subramaniam
- Department of Microbiology and Immunology, Albert Einstein College of Medicine of the Yeshiva University, Bronx, NY 10461, USA
| | | | | | | | | | | |
Collapse
|
20
|
Improved survival of mice deficient in secretory immunoglobulin M following systemic infection with Cryptococcus neoformans. Infect Immun 2009; 78:441-52. [PMID: 19901068 DOI: 10.1128/iai.00506-09] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Cryptococcus neoformans causes severe, and often fatal, disease (cryptococcosis) in immunocompromised patients, particularly in those with HIV/AIDS. Although resistance to cryptococcosis requires intact T-cell immunity, a possible role for antibody/B cells in protection against natural disease has not been definitively established. Previous studies of the antibody response to the C. neoformans capsular polysaccharide glucuronoxylomannan (GXM) have demonstrated that patients who are at increased risk for cryptococcosis have lower serum levels of GXM-reactive IgM than those who are not at risk, leading to the hypothesis that IgM might contribute to resistance to cryptococcosis. To determine the influence of IgM on susceptibility to systemic cryptococcosis in a murine model, we compared the survival of mice deficient in serum IgM (secretory IgM deficient [sIgM(-/-)]) and C57BL/6 x 129Sv (control) mice after intraperitoneal infection with C. neoformans strain 24067 and analyzed the splenic B- and T-cell subsets by flow cytometry and the serum and splenic cytokine/chemokine and serum antibody profiles of each mouse strain. The results showed that sIgM(-/-) mice survived significantly longer than control mice when challenged with 10(5) CFU of C. neoformans 24067. Naïve sIgM(-/-) mice had higher levels of B-1 (CD5(+)) B cells, proinflammatory mediators (interleukin-6 [IL-6], IL-1beta, MIP-1beta, tumor necrosis factor alpha [TNF-alpha], and gamma interferon [IFN-gamma]), and anti-inflammatory mediators (IL-10 and IL-13) and significantly higher titers of GXM-specific IgG2a 3 weeks postinfection. In addition, CD5(+) splenocytes from both mouse strains had fungicidal activity against C. neoformans. Taken together, these results suggest that the inflammatory milieu in sIgM(-/-) mice might confer enhanced resistance to systemic cryptococcosis, stemming in part from the antifungal activity of B-1 B cells.
Collapse
|
21
|
Subramaniam K, Metzger B, Hanau LH, Guh A, Rucker L, Badri S, Pirofski LA. IgM(+) memory B cell expression predicts HIV-associated cryptococcosis status. J Infect Dis 2009; 200:244-51. [PMID: 19527168 DOI: 10.1086/599318] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND The role of B cells in resistance to Cryptococcus neoformans disease (i.e., cryptococcosis) is unknown. Given evidence that IgM(+) memory B cells are required for immunity to other encapsulated pathogens, we hypothesized that these cells might contribute to resistance to cryptococcosis. METHODS We compared levels of IgM expression on memory B cells in 29 HIV-infected individuals who had a history of cryptococcosis (the HIV+CN+ group) with levels in 30 human immunodeficiency virus (HIV)-infected subjects who had no history of cryptococcosis (the HIV+CN- group) and 20 HIV-uninfected subjects who had no history of cryptococcosis (the HIV- group) (cohort 1). We also determined levels of IgM expression on memory B cells in banked samples obtained before cryptococcosis onset from 31 participants in the Multicenter AIDS Cohort Study, of whom 8 had HIV infection and subsequently developed cryptococcosis (the HIV+CN+ group), 8 had HIV infection and did not develop cryptococcosis (the HIV+CN- group), and 15 did not have HIV infection and did not develop cryptococcosis (the HIV- group) (cohort 2). RESULTS In cohort 1, the percentage of memory B cells that expressed IgM was lower among HIV+CN+ subjects, compared with HIV+CN- subjects (P < .01) and HIV- subjects (P < .05); expression of IgM on 50% of memory B cells was a significant predictor of C. neoformans disease status (odds ratio, 5.5; P = .03). In cohort 2, the percentage of memory B cells that expressed IgM was lower in HIV+CN+ subjects than in HIV+CN- subjects (P = .02) and HIV- subjects (P < .01); an IgM(+) memory B cell percentage of 38.5% was a significant predictor of future development of cryptococcosis (odds ratio, 14; P = .02). CONCLUSIONS These findings suggest that HIV-infected persons in whom the percentage of memory B cells that express IgM is decreased might be at greater risk for the development of cryptococcosis.
Collapse
Affiliation(s)
- Krishanthi Subramaniam
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, USA
| | | | | | | | | | | | | |
Collapse
|
22
|
Therapeutic efficacy of a conjugate vaccine containing a peptide mimotope of cryptococcal capsular polysaccharide glucuronoxylomannan. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2008; 15:1176-87. [PMID: 18524882 DOI: 10.1128/cvi.00130-08] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Vaccination with P13, a peptide mimotope of the cryptococcal capsular polysaccharide glucuronoxylomannan (GXM), has been shown to confer protection against a subsequent lethal Cryptococcus neoformans challenge. In this study, we sought to investigate whether P13-based vaccines could be effective in an already-established infection. To address this question, we developed a systemic chronic cryptococcal infection model. We vaccinated chronically infected mice with P13-protein conjugates and monitored their survival. Compared to the controls, the conjugates prolonged the survival of chronically infected mice. The degree of protection was a function of the mouse strain (BALB/c or C57BL/6), the carrier protein (tetanus toxoid or diphtheria toxoid), and the route of infection (intraperitoneal or intravenous). Serum GXM levels were correlated with the day of death, but the correlation was driven by the carrier protein and mouse strain. The passive transfer of heat-treated sera from P13 conjugate-vaccinated mice conferred protection to naïve BALB/c mice, indicating that antibody immunity could contribute to protection. The measurement of peripheral blood cytokine (gamma interferon [IFN-gamma], interleukin-10 [IL-10], and IL-6) gene expression showed that P13 conjugate-vaccinated BALB/c and C57BL/6 mice mounted a strong Th2 (IL-10)-like response relative to the Th1 (IFN-gamma)-like response, with the degree depending on the mouse strain and carrier protein. Taken together, our data suggest that a vaccine could hold promise in the setting of chronic cryptococcosis, and that vaccine efficacy could depend on immunomodulation and augmentation of the natural immune response of the host.
Collapse
|
23
|
Saha DC, Xess I, Zeng WY, Goldman DL. Antibody responses to Cryptococcus neoformans in Indian patients with cryptococcosis. Med Mycol 2008; 46:457-63. [PMID: 18608912 DOI: 10.1080/13693780801961345] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Abstract
An important element of the host response to cryptococcosis is humoral immunity. Specific antibody responses in patients with cryptococcosis however, have not been extensively studied. We analyzed the antibody responses of 22 Indian patients with cryptococcosis, including both HIV+ and HIV- individuals. Sera from 10 Indian patients with AIDS and without cryptococcosis were studied as controls. Antibody responses to cryptococcal proteins were detected by immunoblot, while antibodies to glucuronoxylomannan (GXM), the main component of the cryptococcal capsular polysaccharide were measured by ELISA. Our results indicate that cryptococcosis elicits antibodies to a specific pattern of cytoplasmic proteins. Further, we find that antibody responses to both cytoplasmic proteins and GXM are less robust in HIV+ patients when compared with HIV- patients.
Collapse
|
24
|
Singh N, Perfect JR. Immune reconstitution syndrome associated with opportunistic mycoses. THE LANCET. INFECTIOUS DISEASES 2007; 7:395-401. [PMID: 17521592 DOI: 10.1016/s1473-3099(07)70085-3] [Citation(s) in RCA: 161] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Host immunity is essential in facilitating the eradication of infection. However, immunological recovery and an imbalance characterised by either suboptimum or excessive expression of immune responses can also be harmful to the host. Inflammatory responses triggered by rapid resolution of immunosuppression can lead to a series of localised and systemic reactions, termed immune reconstitution syndrome (IRS), that are often misconstrued as failure of specific antifungal therapy to eliminate the offending fungal pathogen. Recognition of IRS has become increasingly relevant in the context of our current use of potent immunosuppressive agents and immunostimulators that allow rapid manipulation of the immune system. Whereas the conceptual principles of IRS underscore the adverse effects of an overzealous and dysregulated immune response, they also support a role of immunotherapies to augment immunity if induction of endogenous responses is inadequate for the control of infection.
Collapse
Affiliation(s)
- Nina Singh
- Infectious Disease Section, VA Medical Center, University of Pittsburgh, Pittsburgh, PA 15240, USA.
| | | |
Collapse
|
25
|
Singh N, Alexander BD, Lortholary O, Dromer F, Gupta KL, John GT, del Busto R, Klintmalm GB, Somani J, Lyon GM, Pursell K, Stosor V, Munoz P, Limaye AP, Kalil AC, Pruett TL, Garcia-Diaz J, Humar A, Houston S, House AA, Wray D, Orloff S, Dowdy LA, Fisher RA, Heitman J, Wagener MM, Husain S. Cryptococcus neoformans in organ transplant recipients: impact of calcineurin-inhibitor agents on mortality. J Infect Dis 2007; 195:756-64. [PMID: 17262720 PMCID: PMC2746485 DOI: 10.1086/511438] [Citation(s) in RCA: 196] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2006] [Accepted: 10/13/2006] [Indexed: 12/25/2022] Open
Abstract
Variables influencing the risk of dissemination and outcome of Cryptococcus neoformans infection were assessed in 111 organ transplant recipients with cryptococcosis in a prospective, multicenter, international study. Sixty-one percent (68/111) of the patients had disseminated infection. The risk of disseminated cryptococcosis was significantly higher for liver transplant recipients (adjusted hazard ratio [HR], 6.65; P=.048). The overall mortality rate at 90 days was 14% (16/111). The mortality rate was higher in patients with abnormal mental status (P=.023), renal failure at baseline (P=.028), fungemia (P=.006), and disseminated infection (P=.035) and was lower in those receiving a calcineurin-inhibitor agent (P=.003). In a multivariable analysis, the receipt of a calcineurin-inhibitor agent was independently associated with a lower mortality (adjusted HR, 0.21; P=.008), and renal failure at baseline with a higher mortality rate (adjusted HR, 3.14; P=.037). Thus, outcome in transplant recipients with cryptococcosis appears to be influenced by the type of immunosuppressive agent employed. Additionally, discerning the basis for transplant type-specific differences in disease severity has implications relevant for yielding further insights into the pathogenesis of C. neoformans infection in transplant recipients.
Collapse
Affiliation(s)
- Nina Singh
- University of Pittsburgh Medical Center, Pittsburgh, PA 15240, USA.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|