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Hoenigl M, Arastehfar A, Arendrup MC, Brüggemann R, Carvalho A, Chiller T, Chen S, Egger M, Feys S, Gangneux JP, Gold JAW, Groll AH, Heylen J, Jenks JD, Krause R, Lagrou K, Lamoth F, Prattes J, Sedik S, Wauters J, Wiederhold NP, Thompson GR. Novel antifungals and treatment approaches to tackle resistance and improve outcomes of invasive fungal disease. Clin Microbiol Rev 2024; 37:e0007423. [PMID: 38602408 PMCID: PMC11237431 DOI: 10.1128/cmr.00074-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/12/2024] Open
Abstract
SUMMARYFungal infections are on the rise, driven by a growing population at risk and climate change. Currently available antifungals include only five classes, and their utility and efficacy in antifungal treatment are limited by one or more of innate or acquired resistance in some fungi, poor penetration into "sequestered" sites, and agent-specific side effect which require frequent patient reassessment and monitoring. Agents with novel mechanisms, favorable pharmacokinetic (PK) profiles including good oral bioavailability, and fungicidal mechanism(s) are urgently needed. Here, we provide a comprehensive review of novel antifungal agents, with both improved known mechanisms of actions and new antifungal classes, currently in clinical development for treating invasive yeast, mold (filamentous fungi), Pneumocystis jirovecii infections, and dimorphic fungi (endemic mycoses). We further focus on inhaled antifungals and the role of immunotherapy in tackling fungal infections, and the specific PK/pharmacodynamic profiles, tissue distributions as well as drug-drug interactions of novel antifungals. Finally, we review antifungal resistance mechanisms, the role of use of antifungal pesticides in agriculture as drivers of drug resistance, and detail detection methods for antifungal resistance.
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Affiliation(s)
- Martin Hoenigl
- Department of Internal Medicine, Division of Infectious Diseases, ECMM Excellence Center for Medical Mycology, Medical University of Graz, Graz, Austria
- BiotechMed-Graz, Graz, Austria
| | - Amir Arastehfar
- Division of Infectious Diseases, Massachusetts General Hospital, Boston, Massachusetts, USA
- Department of Medicine, Harvard Medical School, Boston, Massachusetts, USA
| | - Maiken Cavling Arendrup
- Unit of Mycology, Statens Serum Institut, Copenhagen, Denmark
- Department of Clinical Microbiology, Rigshospitalet, Copenhagen, Denmark
- Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Roger Brüggemann
- Department of Pharmacy and Radboudumc Institute for Medical Innovation, Radboud University Medical Center, Nijmegen, The Netherlands
- Radboudumc-CWZ Center of Expertise in Mycology, Nijmegen, The Netherlands
| | - Agostinho Carvalho
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal
- ICVS/3B’s - PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Tom Chiller
- Mycotic Diseases Branch, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Sharon Chen
- Centre for Infectious Diseases and Microbiology Laboratory Services, Institute of Clinical Pathology and Medical Research, NSW South Wales Health Pathology, Westmead Hospital, Westmead, Australia
- The University of Sydney, Sydney, Australia
| | - Matthias Egger
- Department of Internal Medicine, Division of Infectious Diseases, ECMM Excellence Center for Medical Mycology, Medical University of Graz, Graz, Austria
| | - Simon Feys
- Department of Microbiology, Immunology and Transplantation, KU Leuven, Leuven, Belgium
- Medical Intensive Care Unit, University Hospitals Leuven, Leuven, Belgium
| | - Jean-Pierre Gangneux
- Centre National de Référence des Mycoses et Antifongiques LA-AspC Aspergilloses chroniques, European Excellence Center for Medical Mycology (ECMM EC), Centre hospitalier Universitaire de Rennes, Rennes, France
- Univ Rennes, CHU Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail) UMR_S 1085, Rennes, France
| | - Jeremy A. W. Gold
- Mycotic Diseases Branch, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Andreas H. Groll
- Department of Pediatric Hematology/Oncology and Infectious Disease Research Program, Center for Bone Marrow Transplantation, University Children’s Hospital, Muenster, Germany
| | - Jannes Heylen
- Department of Microbiology, Immunology and Transplantation, KU Leuven, Leuven, Belgium
- Medical Intensive Care Unit, University Hospitals Leuven, Leuven, Belgium
| | - Jeffrey D. Jenks
- Department of Public Health, Durham County, Durham, North Carolina, USA
- Department of Medicine, Division of Infectious Diseases, Duke University, Durham, North Carolina, USA
| | - Robert Krause
- Department of Internal Medicine, Division of Infectious Diseases, ECMM Excellence Center for Medical Mycology, Medical University of Graz, Graz, Austria
- BiotechMed-Graz, Graz, Austria
| | - Katrien Lagrou
- Department of Microbiology, Immunology and Transplantation, KU Leuven, Leuven, Belgium
- Department of Laboratory Medicine and National Reference Center for Mycosis, University Hospitals Leuven, Leuven, Belgium
| | - Frédéric Lamoth
- Department of Laboratory Medicine and Pathology, Institute of Microbiology, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
- Department of Medicine, Infectious Diseases Service, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Juergen Prattes
- Department of Internal Medicine, Division of Infectious Diseases, ECMM Excellence Center for Medical Mycology, Medical University of Graz, Graz, Austria
- BiotechMed-Graz, Graz, Austria
| | - Sarah Sedik
- Department of Internal Medicine, Division of Infectious Diseases, ECMM Excellence Center for Medical Mycology, Medical University of Graz, Graz, Austria
| | - Joost Wauters
- Department of Microbiology, Immunology and Transplantation, KU Leuven, Leuven, Belgium
- Medical Intensive Care Unit, University Hospitals Leuven, Leuven, Belgium
| | - Nathan P. Wiederhold
- Department of Pathology and Laboratory Medicine, University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA
| | - George R. Thompson
- Department of Internal Medicine, Division of Infectious Diseases University of California-Davis Medical Center, Sacramento, California, USA
- Department of Medical Microbiology and Immunology, University of California-Davis, Davis, California, USA
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Fernández-Ruiz M. Pharmacological management of invasive mold infections in solid organ transplant recipients. Expert Opin Pharmacother 2024; 25:239-254. [PMID: 38436619 DOI: 10.1080/14656566.2024.2326507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Accepted: 02/29/2024] [Indexed: 03/05/2024]
Abstract
INTRODUCTION Solid organ transplant (SOT) recipients face an increased susceptibility to invasive fungal infection (IFI) due to filamentous fungi. Post-transplant invasive aspergillosis (IA) and mucormycosis are related to exceedingly high mortality rates and graft loss risk, and its management involve a unique range of clinical challenges. AREAS COVERED First, the current treatment recommendations for IA and mucormycosis among SOT recipients are critically reviewed, including the supporting evidence. Next, we discussed particular concerns in this patient population, such as drug-drug interactions (DDIs) between triazoles and post-transplant immunosuppression or treatment-related toxicity. The role for immunomodulatory and host-targeted therapies is also considered, as well as the theoretical impact of the intrinsic antifungal activity of calcineurin inhibitors. Finally, a personal opinion is made on future directions in the pharmacological approach to post-transplant IFI. EXPERT OPINION Despite relevant advances in the treatment of mold IFIs in the SOT setting, such as the incorporation of isavuconazole (with lower incidence of DDIs and better tolerability than voriconazole), there remains a large room for improvement in areas such as the position of combination therapy or the optimal strategy for the reduction of baseline immunosuppression. Importantly, future studies should define the specific contribution of newer antifungal agents and classes.
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Affiliation(s)
- Mario Fernández-Ruiz
- Unit of Infectious Diseases, Hospital Universitario "12 de Octubre", Instituto de Investigación Sanitaria Hospital "12 de Octubre" (imas12), Madrid, Spain
- Department of Medicine, School of Medicine, Universidad Complutense, Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos III, Madrid, Spain
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3
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Borges BM, Ramos RBC, Preite NW, Kaminski VDL, Alves de Castro P, Camacho M, Maximo MF, Fill TP, Calich VLG, Traynor AM, Sarikaya-Bayram Ö, Doyle S, Bayram Ö, de Campos CBL, Zelanis A, Goldman GH, Loures FV. Transcriptional profiling of a fungal granuloma reveals a low metabolic activity of Paracoccidioides brasiliensis yeasts and an actively regulated host immune response. Front Cell Infect Microbiol 2023; 13:1268959. [PMID: 37868350 PMCID: PMC10585178 DOI: 10.3389/fcimb.2023.1268959] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Accepted: 09/11/2023] [Indexed: 10/24/2023] Open
Abstract
Granulomas are important immunological structures in the host defense against the fungus Paracoccidioides brasiliensis, the main etiologic agent of Paracoccidioidomycosis (PCM), a granulomatous systemic mycosis endemic in Latin America. We have performed transcriptional and proteomic studies of yeasts present in the pulmonary granulomas of PCM aiming to identify relevant genes and proteins that act under stressing conditions. C57BL/6 mice were infected with 1x106 yeasts and after 8- and 12-weeks of infection, granulomatous lesions were obtained for extraction of fungal and murine RNAs and fungal proteins. Dual transcriptional profiling was done comparing lung cells and P. brasiliensis yeasts from granulomas with uninfected lung cells and the original yeast suspension used in the infection, respectively. Mouse transcripts indicated a lung malfunction, with low expression of genes related to muscle contraction and organization. In addition, an increased expression of transcripts related to the activity of neutrophils, eosinophils, macrophages, lymphocytes as well as an elevated expression of IL-1β, TNF-α, IFN-γ, IL-17 transcripts were observed. The increased expression of transcripts for CTLA-4, PD-1 and arginase-1, provided evidence of immune regulatory mechanisms within the granulomatous lesions. Also, our results indicate iron as a key element for the granuloma to function, where a high number of transcripts related to fungal siderophores for iron uptake was observed, a mechanism of fungal virulence not previously described in granulomas. Furthermore, transcriptomics and proteomics analyzes indicated a low fungal activity within the granuloma, as demonstrated by the decreased expression of genes and proteins related to energy metabolism and cell cycle.
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Affiliation(s)
- Bruno Montanari Borges
- Institute of Science and Technology (ICT), Federal University of São Paulo (UNIFESP), São José dos Campos, SP, Brazil
| | - Rafael Berton Correia Ramos
- Institute of Science and Technology (ICT), Federal University of São Paulo (UNIFESP), São José dos Campos, SP, Brazil
| | - Nycolas Willian Preite
- Institute of Science and Technology (ICT), Federal University of São Paulo (UNIFESP), São José dos Campos, SP, Brazil
| | - Valéria de Lima Kaminski
- Institute of Science and Technology (ICT), Federal University of São Paulo (UNIFESP), São José dos Campos, SP, Brazil
| | - Patrícia Alves de Castro
- Faculty of Pharmaceutical Science of Ribeirão Preto (FCFRP), University of São Paulo (USP), Ribeirão Preto, SP, Brazil
| | - Maurício Camacho
- Institute of Science and Technology (ICT), Federal University of São Paulo (UNIFESP), São José dos Campos, SP, Brazil
| | | | - Taicia Pacheco Fill
- Institute of Chemistry, Universidade Estadual de Campinas, Campinas, SP, Brazil
| | - Vera Lúcia Garcia Calich
- Department of Immunology, Institute of Biomedical Sciences, University of São Paulo (USP), São Paulo, Brazil
| | - Aimee M. Traynor
- Department of Biology, Maynooth University, Maynooth, County Kildare, Ireland
| | | | - Sean Doyle
- Department of Biology, Maynooth University, Maynooth, County Kildare, Ireland
| | - Özgür Bayram
- Department of Biology, Maynooth University, Maynooth, County Kildare, Ireland
| | | | - André Zelanis
- Institute of Science and Technology (ICT), Federal University of São Paulo (UNIFESP), São José dos Campos, SP, Brazil
| | - Gustavo H. Goldman
- Faculty of Pharmaceutical Science of Ribeirão Preto (FCFRP), University of São Paulo (USP), Ribeirão Preto, SP, Brazil
| | - Flávio Vieira Loures
- Institute of Science and Technology (ICT), Federal University of São Paulo (UNIFESP), São José dos Campos, SP, Brazil
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Dambuza IM, Warris A, Salazar F. Unmasking a fungal fire. PLoS Pathog 2023; 19:e1011355. [PMID: 37200244 PMCID: PMC10194863 DOI: 10.1371/journal.ppat.1011355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/20/2023] Open
Abstract
Immune checkpoint inhibitor (ICI) therapy represents a breakthrough cancer treatment by stimulating dysfunctional T cells in the tumour environment to kill cancer cells. Beyond effects on anticancer immunity, ICI therapy may be associated with increased susceptibility to or more rapid resolution of chronic infections, particularly those caused by human fungal pathogens. In this concise review, we summarise recent observations and findings that implicate immune checkpoint blockade in fungal infection outcomes.
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Affiliation(s)
- Ivy M. Dambuza
- MRC Centre for Medical Mycology, University of Exeter, Exeter, United Kingdom
| | - Adilia Warris
- MRC Centre for Medical Mycology, University of Exeter, Exeter, United Kingdom
| | - Fabián Salazar
- MRC Centre for Medical Mycology, University of Exeter, Exeter, United Kingdom
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5
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Wurster S, Watowich SS, Kontoyiannis DP. Checkpoint inhibitors as immunotherapy for fungal infections: Promises, challenges, and unanswered questions. Front Immunol 2022; 13:1018202. [PMID: 36389687 PMCID: PMC9640966 DOI: 10.3389/fimmu.2022.1018202] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Accepted: 10/11/2022] [Indexed: 09/22/2023] Open
Abstract
Opportunistic fungal infections have high mortality in patients with severe immune dysfunction. Growing evidence suggests that the immune environment of invasive fungal infections and cancers share common features of immune cell exhaustion through activation of immune checkpoint pathways. This observation gave rise to several preclinical studies and clinical case reports describing blockade of the Programmed Cell Death Protein 1 and Cytotoxic T-Lymphocyte Antigen 4 immune checkpoint pathways as an adjunct immune enhancement strategy to treat opportunistic fungal infections. The first part of this review summarizes the emerging evidence for contributions of checkpoint pathways to the immunopathology of fungal sepsis, opportunistic mold infections, and dimorphic fungal infections. We then review the potential merits of immune checkpoint inhibitors (ICIs) as an antifungal immunotherapy, including the incomplete knowledge of the mechanisms involved in both immuno-protective effects and toxicities. In the second part of this review, we discuss the limitations of the current evidence and the many unknowns about ICIs as an antifungal immune enhancement strategy. Based on these gaps of knowledge and lessons learned from cancer immunology studies, we outline a research agenda to determine a "sweet spot" for ICIs in medical mycology. We specifically discuss the importance of more nuanced animal models, the need to study ICI-based combination therapy, potential ICI resistance, the role of the immune microenvironment, and the impact of ICIs given as part of oncological therapies on the natural immunity to various pathogenic fungi.
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Affiliation(s)
- Sebastian Wurster
- Department of Infectious Diseases, Infection Control and Employee Health, The University of Texas MD Anderson Cancer Center, Houston, TX, United States
| | - Stephanie S. Watowich
- Department of Immunology, The University of Texas MD Anderson Cancer Center, Houston, TX, United States
| | - Dimitrios P. Kontoyiannis
- Department of Infectious Diseases, Infection Control and Employee Health, The University of Texas MD Anderson Cancer Center, Houston, TX, United States
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Mino M, Yamasaki M, Nabeshima S, Fujimoto Y, Kurushima H, Taniwaki M, Matsumoto N, Kawamoto K, Izumi Y, Otohara M, Hattori N. Cryptococcal Meningitis in a Patient With Rheumatoid Arthritis Treated With Abatacept. J Clin Rheumatol 2021; 27:S701-S702. [PMID: 33065627 DOI: 10.1097/rhu.0000000000001597] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- Masaaki Mino
- From the Department of Respiratory Medicine, Hiroshima Red Cross Hospital and Atomic-bomb Survivors Hospital
| | - Masahiro Yamasaki
- From the Department of Respiratory Medicine, Hiroshima Red Cross Hospital and Atomic-bomb Survivors Hospital
| | - Shinji Nabeshima
- Department of Molecular and Internal Medicine, Institute of Biomedical and Health Sciences, Hiroshima University
| | | | - Hitoshi Kurushima
- General Internal Medicine, Hiroshima Red Cross Hospital and Atomic-bomb Survivors Hospital, Hiroshima, Japan
| | - Masaya Taniwaki
- From the Department of Respiratory Medicine, Hiroshima Red Cross Hospital and Atomic-bomb Survivors Hospital
| | - Naoko Matsumoto
- From the Department of Respiratory Medicine, Hiroshima Red Cross Hospital and Atomic-bomb Survivors Hospital
| | - Kazuma Kawamoto
- From the Department of Respiratory Medicine, Hiroshima Red Cross Hospital and Atomic-bomb Survivors Hospital
| | - Yusuke Izumi
- From the Department of Respiratory Medicine, Hiroshima Red Cross Hospital and Atomic-bomb Survivors Hospital
| | - Masaya Otohara
- From the Department of Respiratory Medicine, Hiroshima Red Cross Hospital and Atomic-bomb Survivors Hospital
| | - Noboru Hattori
- Department of Molecular and Internal Medicine, Institute of Biomedical and Health Sciences, Hiroshima University
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7
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Antimicrobial immunotherapeutics: past, present and future. Emerg Top Life Sci 2021; 5:609-628. [PMID: 34196722 DOI: 10.1042/etls20200348] [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: 04/01/2021] [Revised: 05/21/2021] [Accepted: 06/10/2021] [Indexed: 11/17/2022]
Abstract
In this age of antimicrobial resistance (AMR) there is an urgent need for novel antimicrobials. One area of recent interest is in developing antimicrobial effector molecules, and even cell-based therapies, based on those of the immune system. In this review, some of the more interesting approaches will be discussed, including immune checkpoint inhibitors, Interferons (IFNs), Granulocyte-Macrophage Colony Stimulating Factor (GM-CSF), Chimeric Antigen Receptor (CAR) T cells, Antibodies, Vaccines and the potential role of trained immunity in protection from and/or treatment of infection.
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8
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Higashiguchi M, Yamazaki F, Nishioka K, Kimura H, Matsumoto T. Abatacept for rheumatoid arthritis complicated by disseminated cryptococcosis: a case report. Mod Rheumatol Case Rep 2021; 5:229-235. [PMID: 33843457 DOI: 10.1080/24725625.2021.1909214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
A 78-year-old man developed disseminated cryptococcosis with central nervous system involvement as encapsulated yeast cells were detected in transbronchial biopsy and skin biopsy specimens, and cerebrospinal fluid. Cryptococcus neoformans was confirmed by culture. He had been treated with low-dose prednisolone and methotrexate for rheumatoid arthritis. He started receiving antifungal therapy with intravenous liposomal amphotericin B followed by oral fluconazole. Methotrexate was discontinued. Approximately 4 months after the course of intravenous liposomal amphotericin B was completed, he complained of pain and swelling of the right wrist, which suggested that rheumatoid arthritis was worsening. Abatacept therapy was initiated along with antifungal therapy, and his symptoms relieved. After 24 months of antifungal therapy, although he was still receiving oral fluconazole, he was doing well and the serum cryptococcal antigen had become negative. Disseminated cryptococcosis is an important opportunistic infection associated with low-dose methotrexate for rheumatoid arthritis. Abatacept therapy may be feasible in strictly selected patients with rheumatoid arthritis complicated with cryptococcosis concomitantly with intensive anti-fungal therapy.
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Affiliation(s)
- Masayoshi Higashiguchi
- Department of Internal Medicine, Osaka Anti-Tuberculosis Association Osaka Hospital, Neyagawa, Osaka, Japan
| | - Fumikazu Yamazaki
- Department of Dermatology, Kansai Medical University, Hirakata, Osaka, Japan
| | - Koji Nishioka
- Department of Internal Medicine, Osaka Anti-Tuberculosis Association Osaka Hospital, Neyagawa, Osaka, Japan
| | - Hiromi Kimura
- Department of Internal Medicine, Osaka Anti-Tuberculosis Association Osaka Hospital, Neyagawa, Osaka, Japan
| | - Tomoshige Matsumoto
- Department of Internal Medicine, Osaka Anti-Tuberculosis Association Osaka Hospital, Neyagawa, Osaka, Japan
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9
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Hamashima R, Uchino J, Morimoto Y, Iwasaku M, Kaneko Y, Yamada T, Takayama K. Association of immune checkpoint inhibitors with respiratory infections: A review. Cancer Treat Rev 2020; 90:102109. [PMID: 33038863 DOI: 10.1016/j.ctrv.2020.102109] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2020] [Accepted: 09/23/2020] [Indexed: 12/12/2022]
Abstract
Treatment with immune-checkpoint inhibitors (ICIs) has shown efficacy against a variety of cancer types. The use of anti PD-1, anti PD-L1, and anti CTLA-4 antibodies is rapidly expanding. The side effects of ICIs are very different from conventional cytocidal anticancer and molecular target drugs, and may extend to the digestive organs, respiratory organs, thyroid gland, pituitary gland, skin, and others. Although the details of these adverse events are becoming increasingly apparent, much is unknown regarding the effects and adverse events related to infections. This review focuses specifically on the impact of ICIs on respiratory infections. The impact of ICIs on pathogens varies depending on the significance of the role of T-cell immunity in the immune response to the specific pathogen, as well as the different modes of infection (i.e., acute or chronic), although the impact of ICIs on the clinical outcome of infections in humans has not yet been well studied. Enhanced clearance of many pathogens has been shown because immune checkpoint inhibition activates T cells. In contrast, reactivation of tuberculosis associated with ICI use has been reported, and therefore caution is warranted. In COVID-19 pneumonia, ICI administration may lead to exacerbation; however, it is also possible that ICI may be used for the treatment of COVID-19. It has also been shown that ICI has potential in the treatment of intractable filamentous fungal infections. Therefore, expanded clinical applications are expected.
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Affiliation(s)
- Ryosuke Hamashima
- Department of Pulmonary Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
| | - Junji Uchino
- Department of Pulmonary Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan.
| | - Yoshie Morimoto
- Department of Pulmonary Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
| | - Masahiro Iwasaku
- Department of Pulmonary Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
| | - Yoshiko Kaneko
- Department of Pulmonary Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
| | - Tadaaki Yamada
- Department of Pulmonary Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
| | - Koichi Takayama
- Department of Pulmonary Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
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Mercer DK, O'Neil DA. Innate Inspiration: Antifungal Peptides and Other Immunotherapeutics From the Host Immune Response. Front Immunol 2020; 11:2177. [PMID: 33072081 PMCID: PMC7533533 DOI: 10.3389/fimmu.2020.02177] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Accepted: 08/10/2020] [Indexed: 12/17/2022] Open
Abstract
The purpose of this review is to describe antifungal therapeutic candidates in preclinical and clinical development derived from, or directly influenced by, the immune system, with a specific focus on antimicrobial peptides (AMP). Although the focus of this review is AMP with direct antimicrobial effects on fungi, we will also discuss compounds with direct antifungal activity, including monoclonal antibodies (mAb), as well as immunomodulatory molecules that can enhance the immune response to fungal infection, including immunomodulatory AMP, vaccines, checkpoint inhibitors, interferon and colony stimulating factors as well as immune cell therapies. The focus of this manuscript will be a non-exhaustive review of antifungal compounds in preclinical and clinical development that are based on the principles of immunology and the authors acknowledge the incredible amount of in vitro and in vivo work that has been conducted to develop such therapeutic candidates.
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11
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Leth S, Jensen-Fangel S. Programmed cell death protein 1 (PD-1) in infection. APMIS 2020; 128:177-187. [PMID: 32304591 DOI: 10.1111/apm.13045] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Accepted: 04/08/2020] [Indexed: 12/13/2022]
Abstract
Exhausted and dysfunctional T cells triggered by infection and cancer render the immune system unable to eliminate these pathogens. Pharmacologic blockade of the surface receptors that inhibit T-cell function has shown remarkable success in patients with various malignancies. In this Review, we discuss the emerging evidence of inhibiting checkpoint pathways as a potential role in controlling or clearing infectious diseases. Though interesting tendencies, much work is still needed in order to develop safe strategies that can be translated into clinically relevant outcomes in patients with infections.
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Affiliation(s)
- Steffen Leth
- Department of Infectious Diseases, Aarhus University Hospital, Aarhus, Denmark
| | - Søren Jensen-Fangel
- Department of Infectious Diseases, Aarhus University Hospital, Aarhus, Denmark
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12
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Sk Md OF, Hazra I, Datta A, Mondal S, Moitra S, Chaudhuri S, Das PK, Basu AK, Mishra R, Chaudhuri S. Regulation of key molecules of immunological synapse by T11TS immunotherapy abrogates Cryptococcus neoformans infection in rats. Mol Immunol 2020; 122:207-221. [PMID: 32388483 DOI: 10.1016/j.molimm.2020.04.021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Revised: 04/20/2020] [Accepted: 04/20/2020] [Indexed: 10/24/2022]
Abstract
Cryptococcus neoformans infects and disseminates in hosts with diminished T cell responses. The immunomodulator T11TS (T11 target structure) had profound potential in glioma as well as C. neoformans infected model for disease amelioration. It is been established by our group that T11TS potentiates Calcineurin-NFAT pathway in T cells of C. neoformans infected rats. We investigated the upstream Immunological Synapse (IS) molecules that are vital for the foundation of initial signals for downstream signaling, differentiation and proliferation in T cells. Improved RANTES level in the T11TS treated groups suggests potential recruitment of T cells. Down-regulation of TCRαβ, CD3ζ, CD2, CD45 and CD28 molecules by cryptococcus were boosted after T11TS therapy. Heightened expression of inhibitory molecule CTLA-4 in cryptococcosis was dampened by T11TS. The decline of MHC I, MHC II and CD80 expression on macrophages by C. neoformans were enhanced by T11TS. The dampening of positive regulators and upsurge of negative regulators of the IS during cryptococcosis was reversed with T11TS therapy resulting in enhanced clearance of fungus from the lungs as envisaged by our histological studies. This preclinical study with T11TS opens a new prospect for potential immunotherapeutic intervention against the devastating C. neoformans infection with positive aspect for the long-term solution and a safer immunotherapeutic regimen.
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Affiliation(s)
- Omar Faruk Sk Md
- Department of Laboratory Medicine, School of Tropical Medicine, 108, C. R. Avenue, Kolkata 700073, West Bengal, India; Department of Physiology, University of Calcutta, 92 A.P.C. Road, Kolkata 700009, India
| | - Iman Hazra
- Department of Laboratory Medicine, School of Tropical Medicine, 108, C. R. Avenue, Kolkata 700073, West Bengal, India
| | - Ankur Datta
- Department of Laboratory Medicine, School of Tropical Medicine, 108, C. R. Avenue, Kolkata 700073, West Bengal, India
| | - Somnath Mondal
- Department of Laboratory Medicine, School of Tropical Medicine, 108, C. R. Avenue, Kolkata 700073, West Bengal, India
| | - Saibal Moitra
- Department of Laboratory Medicine, School of Tropical Medicine, 108, C. R. Avenue, Kolkata 700073, West Bengal, India
| | - Suhnrita Chaudhuri
- Centre for Tumor Biology, Barts Cancer Institute, Queen Mary University of London, Charterhouse Square, London, ECIM 6BQ, UK
| | - Prasanta Kumar Das
- Department of Laboratory Medicine, School of Tropical Medicine, 108, C. R. Avenue, Kolkata 700073, West Bengal, India
| | - Anjan Kumar Basu
- Department of Biochemistry and Medical Biotechnology, School of Tropical Medicine, 108, C. R. Avenue, Kolkata 700073, West Bengal, India
| | - Roshnara Mishra
- Department of Physiology, University of Calcutta, 92 A.P.C. Road, Kolkata 700009, India
| | - Swapna Chaudhuri
- Department of Laboratory Medicine, School of Tropical Medicine, 108, C. R. Avenue, Kolkata 700073, West Bengal, India.
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Abers MS, Lionakis MS, Kontoyiannis DP. Checkpoint Inhibition and Infectious Diseases: A Good Thing? Trends Mol Med 2019; 25:1080-1093. [PMID: 31494023 DOI: 10.1016/j.molmed.2019.08.004] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 08/01/2019] [Accepted: 08/07/2019] [Indexed: 12/21/2022]
Abstract
The mammalian immune system has evolved the capacity to detect and destroy tumor cells. Tumors utilize multiple strategies to evade host immune surveillance, including the induction of the checkpoint molecules cytotoxic T lymphocyte-associated protein 4 (CTLA-4) and programmed cell death protein 1 (PD-1) to suppress antitumor immunity. Pharmacologic blockade of these molecules with checkpoint inhibitors (CPIs) restores T cell function and prolongs survival in patients with various malignancies. Emerging evidence suggests that the same checkpoint pathways may play a crucial role during infections. Indeed, CPIs appear promising as immunotherapeutic agents in infectious diseases, although their efficacy varies depending on pathogen-, cell-, and organ-specific factors. More research will be necessary to clarify the effects and safety of CPIs on clinically relevant outcomes of human infection.
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Affiliation(s)
- Michael S Abers
- Fungal Pathogenesis Section, Laboratory of Clinical Immunology and Microbiology (LCIM), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Bethesda, MD, USA
| | - Michail S Lionakis
- Fungal Pathogenesis Section, Laboratory of Clinical Immunology and Microbiology (LCIM), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Bethesda, MD, USA.
| | - Dimitrios P Kontoyiannis
- Department of Infectious Diseases, Infection Control, and Employee Health, The University of Texas MD Anderson Cancer Center (UT-MDACC), Houston, TX, USA
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14
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Shourian M, Qureshi ST. Resistance and Tolerance to Cryptococcal Infection: An Intricate Balance That Controls the Development of Disease. Front Immunol 2019; 10:66. [PMID: 30761136 PMCID: PMC6361814 DOI: 10.3389/fimmu.2019.00066] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Accepted: 01/11/2019] [Indexed: 12/25/2022] Open
Abstract
Cryptococcus neoformans is a ubiquitous environmental yeast and a leading cause of invasive fungal infection in humans. The most recent estimate of global disease burden includes over 200,000 cases of cryptococcal meningitis each year. Cryptococcus neoformans expresses several virulence factors that may have originally evolved to protect against environmental threats, and human infection may be an unintended consequence of these acquired defenses. Traditionally, C. neoformans has been viewed as a purely opportunistic pathogen that targets severely immune compromised hosts; however, during the past decade the spectrum of susceptible individuals has grown considerably. In addition, the closely related strain Cryptococcus gattii has recently emerged in North America and preferentially targets individuals with intact immunity. In parallel to the changing epidemiology of cryptococcosis, an increasing role for host immunity in the pathogenesis of severe disease has been elucidated. Initially, the HIV/AIDS epidemic revealed the capacity of C. neoformans to cause host damage in the absence of adaptive immunity. Subsequently, the development and clinical implementation of highly active antiretroviral treatment (HAART) led to recognition of an immune reconstitution inflammatory syndrome (IRIS) in a subset of HIV+ individuals, demonstrating the pathological role of host immunity in disease. A post-infectious inflammatory syndrome (PIIRS) characterized by abnormal T cell-macrophage activation has also been documented in HIV-negative individuals following antifungal therapy. These novel clinical conditions illustrate the highly complex host-pathogen relationship that underlies severe cryptococcal disease and the intricate balance between tolerance and resistance that is necessary for effective resolution. In this article, we will review current knowledge of the interactions between cryptococci and mammalian hosts that result in a tolerant phenotype. Future investigations in this area have potential for translation into improved therapies for affected individuals.
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Affiliation(s)
- Mitra Shourian
- Translational Research in Respiratory Diseases Program, Meakins-Christie Laboratories, Research Institute of the McGill University Health Centre, Montreal, QC, Canada.,Division of Experimental Medicine, Department of Medicine, McGill University Health Centre, Montreal, QC, Canada
| | - Salman T Qureshi
- Translational Research in Respiratory Diseases Program, Meakins-Christie Laboratories, Research Institute of the McGill University Health Centre, Montreal, QC, Canada.,Division of Experimental Medicine, Department of Medicine, McGill University Health Centre, Montreal, QC, Canada
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15
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Checkpoint inhibitors and aspergillosis in AML: the double hit hypothesis. Lancet Oncol 2018; 18:1571-1573. [PMID: 29208429 DOI: 10.1016/s1470-2045(17)30852-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Revised: 10/04/2017] [Accepted: 10/10/2017] [Indexed: 12/12/2022]
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16
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Roussey JA, Olszewski MA, Osterholzer JJ. Immunoregulation in Fungal Diseases. Microorganisms 2016; 4:microorganisms4040047. [PMID: 27973396 PMCID: PMC5192530 DOI: 10.3390/microorganisms4040047] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Revised: 12/02/2016] [Accepted: 12/06/2016] [Indexed: 02/07/2023] Open
Abstract
This review addresses specific regulatory mechanisms involved in the host immune response to fungal organisms. We focus on key cells and regulatory pathways involved in these responses, including a brief overview of their broader function preceding a discussion of their specific relevance to fungal disease. Important cell types discussed include dendritic cells and regulatory T cells, with a focus on specific studies relating to their effects on immune responses to fungi. We highlight the interleukin-10, programmed cell death 1, and cytotoxic T lymphocyte-associated protein 4 signaling pathways and emphasize interrelationships between these pathways and the regulatory functions of dendritic cells and regulatory T cells. Throughout our discussion, we identify selected studies best illustrating the role of these cells and pathways in response to specific fungal pathogens to provide a contextual understanding of the tightly-controlled network of regulatory mechanisms critical to determining the outcome of exposure to fungal pathogens. Lastly, we discuss two unique phenomena relating to immunoregulation, protective tolerance and immune reactivation inflammatory syndrome. These two clinically-relevant conditions provide perspective as to the range of immunoregulatory mechanisms active in response to fungi.
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Affiliation(s)
- Jonathan A Roussey
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Health System, Ann Arbor, MI 48109, USA.
- Pulmonary Section, Medical Service, VA Ann Arbor Health System, Ann Arbor, MI 48105, USA.
| | - Michal A Olszewski
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Health System, Ann Arbor, MI 48109, USA.
- Pulmonary Section, Medical Service, VA Ann Arbor Health System, Ann Arbor, MI 48105, USA.
- Graduate Program in Immunology, University of Michigan Health System, Ann Arbor, MI 48109, USA.
| | - John J Osterholzer
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Health System, Ann Arbor, MI 48109, USA.
- Pulmonary Section, Medical Service, VA Ann Arbor Health System, Ann Arbor, MI 48105, USA.
- Graduate Program in Immunology, University of Michigan Health System, Ann Arbor, MI 48109, USA.
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17
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Gannavaram S, Bhattacharya P, Ismail N, Kaul A, Singh R, Nakhasi HL. Modulation of Innate Immune Mechanisms to Enhance Leishmania Vaccine-Induced Immunity: Role of Coinhibitory Molecules. Front Immunol 2016; 7:187. [PMID: 27242794 PMCID: PMC4865500 DOI: 10.3389/fimmu.2016.00187] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Accepted: 05/02/2016] [Indexed: 12/14/2022] Open
Abstract
No licensed human vaccines are currently available against any parasitic disease including leishmaniasis. Several antileishmanial vaccine formulations have been tested in various animal models, including genetically modified live-attenuated parasite vaccines. Experimental infection studies have shown that Leishmania parasites utilize a broad range of strategies to undermine effector properties of host phagocytic cells, i.e., dendritic cells (DCs) and macrophages (MΦ). Furthermore, Leishmania parasites have evolved strategies to actively inhibit TH1 polarizing functions of DCs and to condition the infected MΦ toward anti-inflammatory/alternative/M2 phenotype. The altered phenotype of phagocytic cells is characterized by decreased production of antimicrobial reactive oxygen, nitrogen molecules, and pro-inflammatory cytokines, such as IFN-γ, IL-12, and TNF-α. These early events limit the activation of TH1-effector cells and set the stage for pathogenesis. Furthermore, this early control of innate immunity by the virulent parasites results in substantial alteration in the adaptive immunity characterized by reduced proliferation of CD4+ and CD8+ T cells and TH2-biased immunity that results in production of anti-inflammatory cytokines, such as TGF-β, and IL-10. More recent studies have also documented the induction of coinhibitory ligands, such as CTLA-4, PD-L1, CD200, and Tim-3, that induce exhaustion and/or non-proliferation in antigen-experienced T cells. Most of these studies focus on viral infections in chronic phase, thus limiting the direct application of these results to parasitic infections and much less to parasitic vaccines. However, these studies suggest that vaccine-induced protective immunity can be modulated using strategies that enhance the costimulation that might reduce the threshold necessary for T cell activation and conversely by strategies that reduce or block inhibitory molecules, such as PD-L1 and CD200. In this review, we will focus on the polarization of antigen-presenting cells and subsequent role of costimulatory and coinhibitory molecules in mediating vaccine-induced immunity using live-attenuated Leishmania parasites as specific examples.
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Affiliation(s)
- Sreenivas Gannavaram
- Laboratory of Emerging Pathogens, Division of Emerging and Transfusion Transmitted Diseases, Food and Drug Administration , Silver Spring, MD , USA
| | - Parna Bhattacharya
- Laboratory of Emerging Pathogens, Division of Emerging and Transfusion Transmitted Diseases, Food and Drug Administration , Silver Spring, MD , USA
| | - Nevien Ismail
- Laboratory of Emerging Pathogens, Division of Emerging and Transfusion Transmitted Diseases, Food and Drug Administration , Silver Spring, MD , USA
| | - Amit Kaul
- Laboratory of Emerging Pathogens, Division of Emerging and Transfusion Transmitted Diseases, Food and Drug Administration , Silver Spring, MD , USA
| | - Rakesh Singh
- Department of Biochemistry, Banaras Hindu University , Varanasi , India
| | - Hira L Nakhasi
- Laboratory of Emerging Pathogens, Division of Emerging and Transfusion Transmitted Diseases, Food and Drug Administration , Silver Spring, MD , USA
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18
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Trimarchi H, Rengel T, Andrews J, Paulero M, Iotti A, Forastiero A, Lombi F, Pomeranz V, Forrester M, Iriarte R, Agorio I. Belatacept and mediastinal histoplasmosis in a kidney transplant patient. J Nephropathol 2016; 5:84-7. [PMID: 27152295 PMCID: PMC4844914 DOI: 10.15171/jnp.2016.15] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Accepted: 03/08/2016] [Indexed: 12/30/2022] Open
Abstract
Background: In transplantation immunosuppression enhances the appearance of opportunist infections. An ideal balance between the prevention of rejection, the lowest risk of infections and the highest rates of graft survival is a continuous challenge. Lower doses of immunosuppression may diminish the risk of infections, metabolic and hemodynamic complications or even of malignancy, but may expose patients to episodes of acute rejection. New drugs are being developed to improve graft survival at the lowest risk of side effects. Belatacept has recently been introduced in kidney transplantation to inhibit the co-ligand signal of T cell stimulation. It is a drug with a safe profile, is well-tolerated and appears to improve long-term survival of kidney grafts. However, there may be an increase in opportunistic infections which may be facilitated by T cell depression, as Aspergillus sp., Cryptococcus neoformans or tuberculosis.
Case Presentation: We describe a 59-year-old female who developed fever, clinical wasting and a mediastinal mass 31 months after receiving a living non-related kidney transplant while on belatacept therapy. A mediastinal node biopsy disclosed the presence of Histoplasma capsulatum. Infection successfully resolved after appropriate antifungal treatment.
Conclusions: To our knowledge, this is the first reported case of Histoplasma capsulatum in a kidney transplanted patient on belatacept therapy
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Affiliation(s)
- Hernán Trimarchi
- Nephrology Services, Hospital Británico de Buenos Aires, Buenos Aires, Argentina
| | - Tatiana Rengel
- Nephrology Services, Hospital Británico de Buenos Aires, Buenos Aires, Argentina
| | - José Andrews
- Nephrology Services, Hospital Británico de Buenos Aires, Buenos Aires, Argentina
| | - Matías Paulero
- Nephrology Services, Hospital Británico de Buenos Aires, Buenos Aires, Argentina
| | - Alejandro Iotti
- Pathology Services, Hospital Británico de Buenos Aires, Buenos Aires, Argentina
| | - Agustina Forastiero
- Microbiology Services, Hospital Británico de Buenos Aires, Buenos Aires, Argentina
| | - Fernando Lombi
- Nephrology Services, Hospital Británico de Buenos Aires, Buenos Aires, Argentina
| | - Vanesa Pomeranz
- Nephrology Services, Hospital Británico de Buenos Aires, Buenos Aires, Argentina
| | - Mariano Forrester
- Nephrology Services, Hospital Británico de Buenos Aires, Buenos Aires, Argentina
| | - Romina Iriarte
- Nephrology Services, Hospital Británico de Buenos Aires, Buenos Aires, Argentina
| | - Iris Agorio
- Microbiology Services, Hospital Británico de Buenos Aires, Buenos Aires, Argentina
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19
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Jabbour MN, Issa G, Charafeddine K, Simaan Y, Karam M, Khalifeh H, Habib R, Khalifeh I. The immune microenvironment in cutaneous leishmaniasis. J Eur Acad Dermatol Venereol 2014; 29:1170-9. [PMID: 25351105 DOI: 10.1111/jdv.12781] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2014] [Accepted: 09/19/2014] [Indexed: 01/15/2023]
Abstract
BACKGROUND Cutaneous leishmaniasis is an infection that has spread to non-endemic regions, stimulating recent interest for the enhanced understanding of this disease. Downregulation of the CD1a receptor on Langerhans cells has been described in various cutaneous infections. OBJECTIVE In this study, the immune response across different Ridley patterns and parasitic indices is outlined in a case series of cutaneous leishmaniasis. METHODS Skin punch biopsies from the interface of normal and lesional cutaneous leishmaniasis were collected from 33 patients with molecularly confirmed Leishmania tropica or L. major infection. Ridley patterns (2-5) were assessed for various clinicopathological features including age, gender, disease duration, parasitic index and constituents of the inflammatory infiltrate. CD1a, CD68, CD3, CD4, CD8, CD20 and CD138 stains were performed on normal skin tissue, cutaneous leishmaniasis biopsies and cytospin/cell block cytology preparations of cultured leishmania promastigotes. CD1a was quantified per mm2 in the epidermis and dermis. The remaining stains were graded according to a 4-tiered grading system [0 (0-4%); 1 (5-24%); 2 (25-49%); 3 (50-74%) and 4 (75-100%). RESULTS Total CD1a expression significantly decreased (14-fold) from parasitic indices (0-2) to (5-6); (ρ < 0.001). CD1a expression in the epidermis was at least 5-fold lower than normal skin (58 vs. 400 cells/mm2), inversely correlating with the parasitic index. There was an increase in dermal CD1a Langerhans cells (33 vs. 0 cells/mm² in the dermis). CD1a and CD68 staining of amastigotes was strong and diffuse, whereas promastigotes were negative. The major inflammatory infiltrate, in all Ridley patterns, consisted of macrophages and double-negative CD3(+) CD4(-) CD8(-) T lymphocytes. The double-negative CD3 T cells formed a ring around the parasitic laden macrophages. Apart from CD1a, there was no significant difference in inflammatory markers between the various Ridley patterns and parasitic indices. Disease duration did not correlate with Ridley pattern. CONCLUSION The significant decrease in CD1a expression is postulated by two mechanisms; either via direct CD1a receptor uptake by leishmania amastigotes and/or negative feedback inhibition of CD1a Langerhans cells by double-negative CD3 T-regulatory cells. Modulation of the immune microenvironment in cutaneous leishmaniasis represents a potential therapeutic and prophylactic target.
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Affiliation(s)
- M N Jabbour
- Department of Pathology and Laboratory Medicine, American University of Beirut Medical Center, Beirut, Lebanon
| | - G Issa
- Department of Pathology and Laboratory Medicine, American University of Beirut Medical Center, Beirut, Lebanon
| | - K Charafeddine
- Department of Pathology and Laboratory Medicine, American University of Beirut Medical Center, Beirut, Lebanon
| | - Y Simaan
- Department of Biology, University of Balamand, Tripoli, Lebanon
| | - M Karam
- Department of Biology, University of Balamand, Tripoli, Lebanon
| | - H Khalifeh
- Children's Cancer Center Lebanon, American University of Beirut Medical Center, Beirut, Lebanon
| | - R Habib
- Department of Internal Medicine, American University of Beirut Medical Center, Beirut, Lebanon
| | - I Khalifeh
- Department of Pathology and Laboratory Medicine, American University of Beirut Medical Center, Beirut, Lebanon
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20
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Abstract
Breaking immune tolerance against tumor self-antigens is presently an area of intense research in the design of cancer therapies. One possible method to enhance immune system activation against tumor antigens is by blocking the inhibitory co-stimulatory signals mediated by cytotoxic T lymphocyte antigen 4, (CTLA-4) expressed on activated T cells. The fully human monoclonal antibodies that are directed against human CTLA-4, ipilimumab (Medarex/Bristol-Myers Squibb) and CP-675,206 (Pfizer/Abgenix, now Amgen), have demonstrated activity against metastatic melanoma, hormone refractory prostate cancer and other malignancies. They have also uncovered unusual immune-related adverse events manifesting as self-limiting inflammatory reactions of the bowel, skin and pituitary. This article reviews preclinical development and data generated from Phase I, II and III studies with regard to the end points reported and immune-related adverse events.
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Affiliation(s)
- Lee F Langer
- Duke University Medical Center, Department of Surgery, Program in Molecular Therapeutics, Comprehensive Cancer Center, Durham, NC 27710, USA
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21
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Edwards L, Williams AE, Krieg AM, Rae AJ, Snelgrove RJ, Hussell T. Stimulation via Toll-like receptor 9 reduces Cryptococcus neoformans-induced pulmonary inflammation in an IL-12-dependent manner. Eur J Immunol 2005; 35:273-81. [PMID: 15597328 DOI: 10.1002/eji.200425640] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Cytosine-phosphate-guanosine-containing oligodeoxynucleotides (CpG ODN) are important vaccine adjuvants that promote Th1-type immune responses. Cryptococcus neoformans is a serious human pathogen that replicates in the lung but may disseminate systemically leading to meningitis, particularly in immunocompromised individuals. Immunization of susceptible C57BL/6 mice with CpG ODN deviates the immune response from a Th2- toward a Th1-type response following infection with C. neoformans. CpG also induces IL-12, TNF, MCP-1 and macrophage nitric oxide production. CD4(+) and CD8(+) T cells producing IFN-gamma increase in frequency, while those producing IL-5 decrease. More importantly, pulmonary eosinophilia is significantly reduced, an effect that depends on IL-12 and CD8(+) T cells but not NK cells. CpG treatment also reduces the burden of C. neoformans in the lung, an effect that is IL-12-, NK cell- and T cell-independent and probably reflects a direct effect of CpG on pathogen opsonization or an enhancement of macrophage antimicrobial activity. An equivalent beneficial effect is also observed when CpG ODN treatment is delivered during established cryptococcal disease. This is the first study documenting that promotion of lung TLR9 signaling using synthetic agonists enhances host defense. Activation of innate immunity has clear therapeutic potential and may even be beneficial in patients with acquired immune deficiency.
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Affiliation(s)
- Lorna Edwards
- Department of Biological Sciences, Imperial College London, CMMI, London SW7 2AZ, UK
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22
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Graefe SEB, Jacobs T, Wächter U, Bröker BM, Fleischer B. CTLA-4 regulates the murine immune response to Trypanosoma cruzi infection. Parasite Immunol 2004; 26:19-28. [PMID: 15198642 DOI: 10.1111/j.0141-9838.2004.00679.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Infection with Trypanosoma cruzi causes a profound suppression of T cell responsiveness to polyclonal or antigenic stimuli. In this study, we quantified expression of the negative T cell regulatory molecule CTLA-4 in T. cruzi infected mice and analysed its influence on the immune suppression. Levels of splenic CTLA-4 expression were highest around day 10 after infection, reaching 5% in resistant B6D2F1 mice, but exceeding 10% of CD4(+) T cells in C57BL/6 mice that were susceptible to mortal disease. The proliferative response of explanted splenocytes to CD3-mediated stimulation was strongly suppressed in both the susceptible and the resistant strains. Blockade of CTLA-4 in vitro with a monoclonal antibody affected neither proliferative response nor cytokine production (IFN-gamma, IL-4 and IL-2) by splenic T cells from infected C57BL/6 mice. Treatment of mice with anti-CTLA-4 antibody on the day of infection decreased IFN-gamma production and reduced mortality by about 50%. We conclude that high CTLA-4 expression is a hallmark of severe disease in murine T. cruzi infection, and that CTLA-4 has a regulative influence at the early stages during priming of the immune reaction to the parasite, augmenting a strong Th1-biased response.
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Affiliation(s)
- S E B Graefe
- Bernhard-Nocht-Institute, Department of Immunology, Hamburg, Germany.
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23
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Watanabe K, Murakami K, Sato R, Okimoto T, Maeda K, Nasu M, Nishizono A, Fujioka T. CTLA-4 blockade inhibits induction of Helicobacter pylori-associated gastritis in mice. Clin Exp Immunol 2004; 135:29-34. [PMID: 14678261 PMCID: PMC1808916 DOI: 10.1111/j.1365-2249.2004.02338.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
The balance between Th1 and Th2 response determines the outcome of Helicobacter pylori infection. Interferon (IFN)-gamma plays an inductive role in gastric inflammation, whereas interleukin (IL)-4 counterbalances Th1 response and suppresses the development of gastritis. Th cell response is regulated by co-stimulatory factors. A co-stimulatory molecule, cytotoxic T lymphocyte-associated antigen-4 (CTLA-4), plays an inhibitory role in IL-2-dependent cell growth and mediates an optimal inhibitory signal to Th1 and Th2 cells. We administered anti-CTLA-4 monoclonal antibody (MoAb), which blocks CTLA-4 signalling, to examine the relative role for this signalling during maturation of Th1 and Th2 cells in H. pylori infection in mice. Mice treated by anti-CTLA-4 MoAb within the first week of infection showed an inhibition of gastric inflammation, accompanied by an increasing ratio of H. pylori-specific IgG1/IgG2a in serum following infection. Furthermore, the treatment resulted in the higher ratio of IL-4/IFN-gamma by splenocytes in response to H. pylori antigen at 6 weeks after infection, compared with untreated mice. These results suggest that the predominance of Th2 response by CTLA-4 blockade leads to an inhibition of the development of gastric inflammation. CTLA-4 signalling could contribute to the regulation of Th subsets and the development of gastric inflammation in H. pylori infection.
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Affiliation(s)
- K Watanabe
- Department of Infectious Diseases and General Medicine, Oita University, Oita, Japan.
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24
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Prud'homme GJ. Altering immune tolerance therapeutically: the power of negative thinking. J Leukoc Biol 2003; 75:586-99. [PMID: 14657212 DOI: 10.1189/jlb.0803394] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The etiology of most human autoimmune diseases remains largely unknown. However, investigators have identified several negative regulatory mechanisms acting at the level of innate and/or adaptive immunity. Mutations resulting in a deficiency of some key regulatory molecules are associated with systemic or organ-specific inflammatory disorders, which often have a prominent autoimmune component. Genetic studies have implicated the negative regulator cytotoxic T-lymphocyte antigen 4 (CTLA-4) and other regulatory molecules in human autoimmune diseases. In addition to CTLA-4, key inhibitory molecules include programmed death 1 and B and T lymphocyte attenuator. Transforming growth factor beta1 and interleukin-10 also play major anti-inflammatory and regulatory roles. Tumor cells and infectious agents use negative regulatory pathways to escape immunity. The therapeutic blockage of negative signaling (particularly of CTLA-4) increases immunity against tumor antigens but also induces or aggravates autoimmune diseases. It appears that under normal conditions, the immune system is under strong "negative influences" that prevent autoimmunity and that release of this suppression results in disease. Regulation involves communication between the immune system and nonlymphoid tissues, and the latter can deliver inhibitory or stimulatory signals. Recent studies reveal that the generation of negative signals by selective engagement of inhibitory molecules is feasible and is likely to be of therapeutic benefit in autoimmune diseases and allograft rejection.
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Affiliation(s)
- Gérald J Prud'homme
- Department of Laboratory Medicine and Pathobiology, St Michael's Hospital, University of Toronto, Ontario, Canada.
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25
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Humphreys IR, Edwards L, Walzl G, Rae AJ, Dougan G, Hill S, Hussell T. OX40 ligation on activated T cells enhances the control of Cryptococcus neoformans and reduces pulmonary eosinophilia. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2003; 170:6125-32. [PMID: 12794142 DOI: 10.4049/jimmunol.170.12.6125] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Pulmonary eosinophilia induced in C57BL/6 mice after Cryptococcus neoformans infection is driven by CD4(+) Th2 cells. The immunological mechanisms that protect against eosinophilia are not fully understood. Interaction of OX40 (CD134) and its ligand, OX40L, has been implicated in T cell activation and cell migration. Unlike CD28, OX40 is only expressed on T cells 1-2 days after Ag activation. Manipulation of this pathway would therefore target recently activated T cells, leaving the naive repertoire unaffected. In this study, we show that engagement of OX40 by an OX40L:Ig fusion protein drives IFN-gamma production by CD4(+) T cells and reduces eosinophilia and C. neoformans burden in the lung. Using gene-depleted mice, we show that reduction of eosinophilia and pathogen burden requires IL-12 and/or IFN-gamma. C. neoformans infection itself only partially induces OX40L expression by APCs. Provision of exogenous OX40L reveals a critical role of this pathway in the prevention of C. neoformans-induced eosinophilia.
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MESH Headings
- Adjuvants, Immunologic/administration & dosage
- Adjuvants, Immunologic/biosynthesis
- Adjuvants, Immunologic/metabolism
- Adjuvants, Immunologic/physiology
- Animals
- Antigens, Differentiation/administration & dosage
- Antigens, Differentiation/metabolism
- Bronchi/immunology
- Bronchi/metabolism
- Bronchi/microbiology
- CD4-Positive T-Lymphocytes/immunology
- CD4-Positive T-Lymphocytes/metabolism
- CD4-Positive T-Lymphocytes/microbiology
- Cryptococcus neoformans/growth & development
- Cryptococcus neoformans/immunology
- Down-Regulation/immunology
- Eosinophils/immunology
- Eosinophils/pathology
- Female
- Injections, Intraperitoneal
- Interferon-gamma/biosynthesis
- Interferon-gamma/deficiency
- Interferon-gamma/genetics
- Interferon-gamma/physiology
- Ligands
- Lung/immunology
- Lung/metabolism
- Lung/microbiology
- Lymphocyte Activation/immunology
- Membrane Glycoproteins/administration & dosage
- Membrane Glycoproteins/metabolism
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- OX40 Ligand
- Pulmonary Eosinophilia/genetics
- Pulmonary Eosinophilia/microbiology
- Pulmonary Eosinophilia/pathology
- Pulmonary Eosinophilia/prevention & control
- Receptors, OX40
- Receptors, Tumor Necrosis Factor
- Recombinant Fusion Proteins/administration & dosage
- Recombinant Fusion Proteins/metabolism
- T-Lymphocyte Subsets/immunology
- T-Lymphocyte Subsets/metabolism
- T-Lymphocyte Subsets/microbiology
- Tumor Necrosis Factor Receptor Superfamily, Member 7/administration & dosage
- Tumor Necrosis Factor Receptor Superfamily, Member 7/biosynthesis
- Tumor Necrosis Factor Receptor Superfamily, Member 7/metabolism
- Tumor Necrosis Factors
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Affiliation(s)
- Ian R Humphreys
- Center for Molecular Microbiology and Infection, Department of Biochemistry, Imperial College of Science, Technology and Medicine, London, United Kingdom
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26
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Vecchiarelli A, Pietrella D, Bistoni F, Kozel TR, Casadevall A. Antibody to Cryptococcus neoformans capsular glucuronoxylomannan promotes expression of interleukin-12Rbeta2 subunit on human T cells in vitro through effects mediated by antigen-presenting cells. Immunology 2002; 106:267-72. [PMID: 12047756 PMCID: PMC1782713 DOI: 10.1046/j.1365-2567.2002.01419.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The results reported herein show that T cells responding to encapsulated Cryptococcus neoformans cells had reduced expression of interleukin-12 receptor beta2 (IL-12Rbeta2) in comparison to those responding to non-encapsulated cells. This suggested that encapsulation with glucuronoxylomannan (GXM), the principal constituent of the C. neoformans polysaccharide antiphagocytic capsule, inhibited expression of the IL-12Rbeta2 subunit on T cells responding to cryptococcal antigens. Addition of GXM-binding monoclonal antibody (mAb) overcame this effect by promoting IL-12Rbeta2 expression and by decreasing IL-1R expression on T cells. This effect may be a consequence of mAb-induced changes on antigen-presenting cells (APC) that are closely related to increased phagocytosis. Blocking of phagocytosis with monoiodacetic acid (MIA) precluded up-regulation of B7 expression on APC and was associated with diminished IL-12Rbeta2 expression on T cells. The observed effects on T cells were interpreted as a consequence of increased APC function due to enhanced phagocytosis. These findings suggest a mechanism by which specific antibody can promote the polarization of the cellular immune response towards a Th1-like response and thus contribute to an enhanced cellular immune response against C. neoformans.
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Affiliation(s)
- Anna Vecchiarelli
- Microbiology Section, Department of Experimental Medicine and Biochemical Sciences, University of Perugia, Perugia, Italy.
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27
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Nichols KL, Bauman SK, Schafer FB, Murphy JW. Differences in components at delayed-type hypersensitivity reaction sites in mice immunized with either a protective or a nonprotective immunogen of Cryptococcus neoformans. Infect Immun 2002; 70:591-600. [PMID: 11796587 PMCID: PMC127722 DOI: 10.1128/iai.70.2.591-600.2002] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2001] [Revised: 10/11/2001] [Accepted: 10/30/2001] [Indexed: 11/20/2022] Open
Abstract
Cell-mediated immunity is the major protective mechanism against Cryptococcus neoformans. Delayed swelling reactions, i.e., delayed-type hypersensitivity (DTH), in response to an intradermal injection of specific antigen are used as a means of detecting a cell-mediated immune (CMI) response to the antigen. We have found previously that the presence of an anticryptococcal DTH response in mice is not always indicative of protection against a cryptococcal infection. Using one immunogen that induces a protective anticryptococcal CMI response and one that induces a nonprotective response, we have shown that mice immunized with the protective immunogen undergo a classical DTH response characterized by mononuclear cell and neutrophil infiltrates and the presence of gamma interferon and NO. In contrast, immunization with the nonprotective immunogen results in an influx of primarily neutrophils and production of tumor necrosis factor alpha (TNF-alpha) at the DTH reaction site. Even when the anticryptococcal DTH response was augmented by blocking the down-regulator, CTLA-4 (CD152), on T cells in the mice given the nonprotective immunogen, the main leukocyte population infiltrating the DTH reaction site is the neutrophil. Although TNF-alpha is increased at the DTH reaction site in mice immunized with the nonprotective immunogen, it is unlikely that TNF-alpha activates the neutrophils, because the density of TNF receptors on the neutrophils is reduced below control levels. Uncoupling of DTH reactivity and protection has been demonstrated in other infectious-disease models; however, the mechanisms differ from our model. These findings stress the importance of defining the cascade of events occurring in response to various immunogens and establishing the relationships between protection and DTH reactions.
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MESH Headings
- Animals
- Antigens, CD/metabolism
- Antigens, Fungal/immunology
- Cryptococcosis/prevention & control
- Cryptococcus neoformans/immunology
- Female
- Granulocytes/metabolism
- Hypersensitivity, Delayed/immunology
- Interferon-gamma/genetics
- Mice
- Mice, Inbred CBA
- Nitric Oxide/metabolism
- RNA, Messenger/metabolism
- Receptors, Tumor Necrosis Factor/metabolism
- Receptors, Tumor Necrosis Factor, Type I
- Receptors, Tumor Necrosis Factor, Type II
- Tumor Necrosis Factor-alpha/genetics
- Vaccination
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Affiliation(s)
- Kasie L Nichols
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73190, USA
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28
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Chiapello L, Iribarren P, Cervi L, Rubinstein H, Masih DT. Mechanisms for induction of immunosuppression during experimental cryptococcosis: role of glucuronoxylomannan. Clin Immunol 2001; 100:96-106. [PMID: 11414750 DOI: 10.1006/clim.2001.5046] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In previous work we have demonstrated that spleen mononuclear (Spm) cells from rats obtained 14 days after infection with Cryptococcus neoformans showed a diminution in proliferative response to Concanavalin A (Con A). In this study we further investigate some characteristics of the Spm cell population involved in the immunosuppressor phenomenon induced by C. neoformans. We observed that unstimulated Spm cells expressing T-cell receptor (TCR+) from infected rats were reduced in number after 96 h of culture. When the Spm cells from infected rats were stimulated with Con A, increased production of IL-10, reduced levels of IL-2, and decreased CD11a surface expression were shown. These immunosuppressor phenomena were also observed when the capsular polysaccharide, glucuronoxylomannan (GXM), was added to cultures of Spm cells from normal rats. However, GXM had a more pronounced effect in reducing the number of cells surviving in culture than that observed during infection and produced an increase in IL-4 production by Con-A-stimulated Spm cells. Addition of anti-IL-10 monoclonal antibody to cultures restored the lymphoproliferation of Spm cells from infected animals, indicating that IL-10 production is a suppressor mechanism of cell-mediated immunity during experimental infection. The results presented here indicate that at least two mechanisms mediate the nonspecific suppression in this model of cryptococcosis: IL-10 production and diminution of the number of T cells. GXM could be involved, since it has a pronounced effect in the reduction of Spm cells in vitro.
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Affiliation(s)
- L Chiapello
- Micología, Universidad Nacional de Córdoba, Córdoba, 5000, Argentina
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29
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Pietrella D, Cherniak R, Strappini C, Perito S, Mosci P, Bistoni F, Vecchiarelli A. Role of mannoprotein in induction and regulation of immunity to Cryptococcus neoformans. Infect Immun 2001; 69:2808-14. [PMID: 11292692 PMCID: PMC98228 DOI: 10.1128/iai.69.5.2808-2814.2001] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Our previous observations showed that mannoprotein (MP) induces early and massive production of interleukin-12 (IL-12) in vitro. This study was designed to investigate whether this phenomenon could be applied in vivo and to determine the biological significance of MP in Cryptococcus neoformans infection. The results reported here show that MP treatment induces IL-12 secretion by splenic macrophages and IL-12 p40 mRNA in the brain. During C. neoformans infection, MP reinforced IL-12 and IFN-gamma secretion that coincided with enhanced antifungal activity of natural effector cells, early resolution of the inflammatory process, and clearance of fungal load from the brain. These studies show that MP is a key inflammatory mediator that induces a protective immune response against C. neoformans infection. This information can be used to facilitate the design of a rational approach to manipulate the immune response to C. neoformans.
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Affiliation(s)
- D Pietrella
- Microbiology Section, Department of Experimental Medicine and Biochemical Sciences, University of Perugia, 06122 Perugia, Italy
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30
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Pietrella D, Perito S, Bistoni F, Vecchiarelli A. Cytotoxic T lymphocyte antigen costimulation influences T-cell activation in response to Cryptococcus neoformans. Infect Immun 2001; 69:1508-14. [PMID: 11179320 PMCID: PMC98049 DOI: 10.1128/iai.69.3.1508-1514.2001] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The kinetics of cytotoxic T lymphocyte antigen 4 (CTLA-4) expression on T cells responding to Cryptococcus neoformans and its role in regulating the T-cell response were examined. Using peripheral blood mononuclear cells stimulated with encapsulated or acapsular C. neoformans we showed that (i) the encapsulated strain augmented CTLA-4 expression on the T-cell surface while the acapsular strain was a weaker modulator, (ii) CTLA-4 molecules were rapidly up-regulated after the addition of encapsulated C. neoformans, (iii) CTLA-4 was up-regulated predominantly in CD4+ T cells responding to C. neoformans, and (iv) blockage of CTLA-4 with (Fab')2 of monoclonal antibody to CTLA-4 induced T-cell proliferation that paralleled the enhancement of interleukin-2 and gamma interferon production. These results suggest that capsular material, the major virulence factor of C. neoformans, promotes synthesis and expression of CTLA-4 molecules predominantly in CD4+ T cells. CTLA-4-mediated deactivation is due not to lack of costimulation but to specific recognition of CTLA-4 for B7 molecules. This appears to be a new mechanism by which C. neoformans may elude the host immune response.
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Affiliation(s)
- D Pietrella
- Microbiology Section, Department of Experimental Medicine and Biochemical Sciences, University of Perugia, Perugia, Italy
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