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Alonaizan R. Molecular regulation of NLRP3 inflammasome activation during parasitic infection. Biosci Rep 2024; 44:BSR20231918. [PMID: 38623843 PMCID: PMC11096646 DOI: 10.1042/bsr20231918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2023] [Revised: 03/26/2024] [Accepted: 04/12/2024] [Indexed: 04/17/2024] Open
Abstract
Parasitic diseases are a serious global health concern, causing many common and severe infections, including Chagas disease, leishmaniasis, and schistosomiasis. The NLRP3 inflammasome belongs to the NLR (nucleotide-binding domain leucine-rich-repeat-containing proteins) family, which are cytosolic proteins playing key roles in the detection of pathogens. NLRP3 inflammasomes are activated in immune responses to Plasmodium, Leishmania, Toxoplasma gondii, Entamoeba histolytica, Trypanosoma cruzi, and other parasites. The role of NLRP3 is not fully understood, but it is a crucial component of the innate immune response to parasitic infections and its functions as a sensor triggering the inflammatory response to the invasive parasites. However, while this response can limit the parasites' growth, it can also result in potentially catastrophic host pathology. This makes it essential to understand how NLRP3 interacts with parasites to initiate the inflammatory response. Plasmodium hemozoin, Leishmania glycoconjugate lipophosphoglycan (LPG) and E. histolytica Gal/GalNAc lectin can stimulate NLRP3 activation, while the dense granule protein 9 (GRA9) of T. gondii has been shown to suppress it. Several other parasitic products also have diverse effects on NLRP3 activation. Understanding the mechanism of NLRP3 interaction with these products will help to develop advanced therapeutic approaches to treat parasitic diseases. This review summarizes current knowledge of the NLRP3 inflammasome's action on the immune response to parasitic infections and aims to determine the mechanisms through which parasitic molecules either activate or inhibit its action.
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Affiliation(s)
- Rasha Alonaizan
- Faculty of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia
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Suresh Kumar Meena Kumari M, Liu P, Jump K, Morales Y, Miller EA, Shecter I, Stadecker MJ, Kalantari P. NLRP3 and AIM2 inflammasomes exacerbate the pathogenic Th17 cell response to eggs of the helminth Schistosoma mansoni. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.11.584371. [PMID: 38559160 PMCID: PMC10979858 DOI: 10.1101/2024.03.11.584371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Infection with the helminth Schistosoma mansoni can cause exacerbated morbidity and mortality via a pathogenic host CD4 T cell-mediated immune response directed against parasite egg antigens, with T helper (Th) 17 cells playing a major role in the development of severe granulomatous hepatic immunopathology. The role of inflammasomes in intensifying disease has been reported; however, neither the types of caspases and inflammasomes involved, nor their impact on the Th17 response are known. Here we show that enhanced egg-induced IL-1β secretion and pyroptotic cell death required both caspase-1 and caspase-8 as well as NLRP3 and AIM2 inflammasome activation. Schistosome genomic DNA activated AIM2, whereas reactive oxygen species, potassium efflux and cathepsin B, were the major activators of NLRP3. NLRP3 and AIM2 deficiency led to a significant reduction in pathogenic Th17 responses, suggesting their crucial and non-redundant role in promoting inflammation. Additionally, we show that NLRP3- and AIM2-induced IL-1β suppressed IL-4 and protective Type I IFN (IFN-I) production, which further enhanced inflammation. IFN-I signaling also curbed inflammasome- mediated IL-1β production suggesting that these two antagonistic pathways shape the severity of disease. Lastly, Gasdermin D (Gsdmd) deficiency resulted in a marked decrease in egg-induced granulomatous inflammation. Our findings establish NLRP3/AIM2-Gsdmd axis as a central inducer of pathogenic Th17 responses which is counteracted by IFN-I pathway in schistosomiasis.
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Affiliation(s)
- Madhusoodhanan Suresh Kumar Meena Kumari
- Department of Veterinary and Biomedical Sciences, Center for Molecular Immunology and Infectious Disease, Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Pengyu Liu
- Department of Veterinary and Biomedical Sciences, Center for Molecular Immunology and Infectious Disease, Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Kaile Jump
- Department of Veterinary and Biomedical Sciences, Center for Molecular Immunology and Infectious Disease, Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Yoelkys Morales
- Department of Immunology, Tufts University School of Medicine, Boston, Massachusetts, United States of America
| | - Emily A Miller
- Department of Immunology, Tufts University School of Medicine, Boston, Massachusetts, United States of America
| | - Ilana Shecter
- Department of Immunology, Tufts University School of Medicine, Boston, Massachusetts, United States of America
| | - Miguel J. Stadecker
- Department of Immunology, Tufts University School of Medicine, Boston, Massachusetts, United States of America
| | - Parisa Kalantari
- Department of Veterinary and Biomedical Sciences, Center for Molecular Immunology and Infectious Disease, Pennsylvania State University, University Park, Pennsylvania, United States of America
- Department of Immunology, Tufts University School of Medicine, Boston, Massachusetts, United States of America
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Cui JZ, Chew ZH, Lim LHK. New insights into nucleic acid sensor AIM2: The potential benefit in targeted therapy for cancer. Pharmacol Res 2024; 200:107079. [PMID: 38272334 DOI: 10.1016/j.phrs.2024.107079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Revised: 01/17/2024] [Accepted: 01/19/2024] [Indexed: 01/27/2024]
Abstract
The AIM2 inflammasome represents a multifaceted oligomeric protein complex within the innate immune system, with the capacity to perceive double-stranded DNA (dsDNA) and engage in diverse physiological reactions and disease contexts, including cancer. While originally conceived as a discerning DNA sensor, AIM2 has demonstrated its capability to discern various nucleic acid variations, encompassing RNA and DNA-RNA hybrids. Through its interaction with nucleic acids, AIM2 orchestrates the assembly of a complex involving multiple proteins, aptly named the AIM2 inflammasome, which facilitates the enzymatic cleavage of proinflammatory cytokines, namely pro-IL-1β and pro-IL-18. This process, in turn, underpins its pivotal biological role. In this review, we provide a systematic summary and discussion of the latest advancements in AIM2 sensing various types of nucleic acids. Additionally, we discuss the modulation of AIM2 activation, which can cause cell death, including pyroptosis, apoptosis, and autophagic cell death. Finally, we fully illustrate the evidence for the dual role of AIM2 in different cancer types, including both anti-tumorigenic and pro-tumorigenic functions. Considering the above information, we uncover the therapeutic promise of modulating the AIM2 inflammasome in cancer treatment.
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Affiliation(s)
- Jian-Zhou Cui
- Translational Immunology Program, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; NUS Immunology Program, Life Sciences Institute, National University of Singapore, Singapore; NUS-Cambridge Immunophenotyping Centre, Life Science Institute, National University of Singapore, Singapore.
| | - Zhi Huan Chew
- Translational Immunology Program, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; NUS Immunology Program, Life Sciences Institute, National University of Singapore, Singapore; NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore; Department of Microbiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Lina H K Lim
- Translational Immunology Program, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; NUS Immunology Program, Life Sciences Institute, National University of Singapore, Singapore; NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore; Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.
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Barroso DH, Nóbrega ODT, de Araújo CN, Freire GSM, Martins SS, Rodrigues BC, Gomes CM, Sampaio RNR. The Presence of Leishmania braziliensis DNA in the Nasal Mucosa of Cutaneous Leishmaniasis Patients and the Search for Possible Clinical and Immunological Patterns of Disease Progression: A Cross Sectional Study. Front Cell Infect Microbiol 2021; 11:744163. [PMID: 34722337 PMCID: PMC8551912 DOI: 10.3389/fcimb.2021.744163] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Accepted: 09/28/2021] [Indexed: 11/15/2022] Open
Abstract
Leishmania braziliensis is the most important causal agent of American tegumentary leishmaniasis (ATL), and 3 to 5% of patients develop mucosal lesions. The mechanisms related to parasite and host immune interactions and the parasite life cycle that lead to dissemination to the mucosa are poorly understood. We aimed to detect L. braziliensis DNA in the nasal mucosa of cutaneous leishmaniasis (CL) patients with early mucous dissemination and to relate those findings to specific inflammatory responses. Nasal swabs were collected from patients with the cutaneous form of ATL. L. braziliensis DNA was investigated using TaqMan-based real-time PCR. The levels of serum cytokines (IL-12, IL-6, TNF-α, IL-10, IL-1β and IL-8) were measured by a multiplex cytometric array. A Poisson regression model was used to test prevalence ratios (PRs) and multivariate interactions of clinical and laboratory characteristics. Of the 79 CL patients, 24 (30%) had L. braziliensis DNA in the nasal mucosa. In the multivariate model, parasite DNA presence in mucosa was associated with a reduction in IL-12 levels (PR = 0.440; p=0.034), increased IL-6 levels (PR = 1.001; p=0.002) and a higher number of affected body segments (PR = 1.65; p<0.001). In this study, we observed a higher rate of early dissemination to the nasal mucosa than what was previously described. We suggest that an enhanced Th1 profile characterized by higher IL-12 is important for preventing dissemination of L. braziliensis to the mucosa. Further evaluation of parasite-related interactions with the host immunological response is necessary to elucidate the dissemination mechanisms of Leishmania.
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Affiliation(s)
- Daniel Holanda Barroso
- Programa de Pós-Graduação em Ciências Médicas, Faculdade de Medicina, Universidade de Brasília (UnB), Brasília, Brazil.,Hospital Universitário de Brasília, Universidade de Brasília, Brasília, Brazil.,Laboratório de Dermatomicologia da Faculdade de Medicina, Universidade de Brasília, Brasília, Brazil
| | - Otávio de Toledo Nóbrega
- Programa de Pós-Graduação em Ciências Médicas, Faculdade de Medicina, Universidade de Brasília (UnB), Brasília, Brazil.,Pós-Graduação de Ciências da Saúde da Faculdade de Ciências Saúde, Universidade de Brasília, Brasília, Brazil
| | - Carla Nunes de Araújo
- Programa de Pós-Graduação em Ciências Médicas, Faculdade de Medicina, Universidade de Brasília (UnB), Brasília, Brazil
| | | | - Sofia Sales Martins
- Hospital Universitário de Brasília, Universidade de Brasília, Brasília, Brazil.,Pós-Graduação de Ciências da Saúde da Faculdade de Ciências Saúde, Universidade de Brasília, Brasília, Brazil
| | - Bruna Côrtes Rodrigues
- Programa de Pós-Graduação em Ciências Médicas, Faculdade de Medicina, Universidade de Brasília (UnB), Brasília, Brazil.,Hospital Universitário de Brasília, Universidade de Brasília, Brasília, Brazil
| | - Ciro Martins Gomes
- Programa de Pós-Graduação em Ciências Médicas, Faculdade de Medicina, Universidade de Brasília (UnB), Brasília, Brazil.,Hospital Universitário de Brasília, Universidade de Brasília, Brasília, Brazil.,Laboratório de Dermatomicologia da Faculdade de Medicina, Universidade de Brasília, Brasília, Brazil.,Programa de Pós-Graduação em Medicina Tropical, Faculdade de Medicina, Universidade de Brasília (UnB), Brasília, Brazil
| | - Raimunda Nonata Ribeiro Sampaio
- Programa de Pós-Graduação em Ciências Médicas, Faculdade de Medicina, Universidade de Brasília (UnB), Brasília, Brazil.,Hospital Universitário de Brasília, Universidade de Brasília, Brasília, Brazil.,Laboratório de Dermatomicologia da Faculdade de Medicina, Universidade de Brasília, Brasília, Brazil.,Pós-Graduação de Ciências da Saúde da Faculdade de Ciências Saúde, Universidade de Brasília, Brasília, Brazil
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Interplays between inflammasomes and viruses, bacteria (pathogenic and probiotic), yeasts and parasites. Immunol Lett 2020; 228:1-14. [PMID: 32971149 PMCID: PMC7505743 DOI: 10.1016/j.imlet.2020.09.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 08/30/2020] [Accepted: 09/14/2020] [Indexed: 02/06/2023]
Abstract
In recent years, scientists studying the molecular mechanisms of inflammation have discovered an amazing phenomenon - the inflammasome - a component of the innate immune system that can regulate the functional activity of effector cells during inflammation. At present, it is known that inflammasomes are multimolecular complexes (cytosolic multiprotein oligomers of the innate immune system) that contain many copies of receptors recognizing the molecular structures of cell-damaging factors and pathogenic agents. Inflammasomes are mainly formed in myeloid cells, and their main function is participation in the cleavage of the pro-IL-1β and pro-IL-18 cytokines into their biologically active forms (IL-1β, IL-18). Each type of microorganism influences particular inflammasome activation, and long-term exposure of the organism to viruses, bacteria, yeasts or parasites, among others, can induce uncontrolled inflammation and autoinflammatory diseases. Therefore, this review aims to present the most current scientific data on the molecular interplay between inflammasomes and particular microorganisms. Knowledge about the mechanisms responsible for the interaction between the host and certain types of microorganisms could contribute to the individuation of innovative strategies for the treatment of uncontrolled inflammation targeting a specific type of inflammasome activated by a specific type of pathogen.
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Harrington V, Gurung P. Reconciling protective and pathogenic roles of the NLRP3 inflammasome in leishmaniasis. Immunol Rev 2020; 297:53-66. [PMID: 32564424 DOI: 10.1111/imr.12886] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 05/12/2020] [Accepted: 05/20/2020] [Indexed: 12/29/2022]
Abstract
Leishmaniasis is a global health problem that affects more than 2 billion people worldwide. Recent advances in research have demonstrated critical roles for cytoplasmic sensors and inflammasomes during Leishmania spp. infection and pathogenesis. Specifically, several studies have focused on the role of nod-like receptor family, pyrin domain-containing protein 3 (NLRP3) inflammasome and inflammasome-associated cytokines IL-1β and IL-18 in leishmaniasis. Despite these studies, our understanding of the priming and activation events that lead to NLRP3 inflammasome activation during Leishmania spp. infection is limited. Furthermore, whether NLRP3 plays a protective or pathogenic role during Leishmania spp. infection is far from resolved, with some studies showing a protective role and others showing a pathogenic role. In this review, we performed a critical review of the literature to provide a current update on priming and activating signals required for NLRP3 inflammasome activation during Leishmania spp. infection. Finally, we provide a thorough review of the literature to reconcile differences in the observed protective vs pathogenic roles of the NLRP3 inflammasome during Leishmania spp. infection.
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Affiliation(s)
| | - Prajwal Gurung
- Inflammation Program, University of Iowa, Iowa City, IA, USA.,Department of Internal Medicine, University of Iowa, Iowa City, IA, USA.,Immunology Graduate Program, University of Iowa, Iowa City, IA, USA.,Interdisciplinary Graduate Program in Human Toxicology, University of Iowa, Iowa City, IA, USA
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Lecoeur H, Prina E, Rosazza T, Kokou K, N’Diaye P, Aulner N, Varet H, Bussotti G, Xing Y, Milon G, Weil R, Meng G, Späth GF. Targeting Macrophage Histone H3 Modification as a Leishmania Strategy to Dampen the NF-κB/NLRP3-Mediated Inflammatory Response. Cell Rep 2020; 30:1870-1882.e4. [DOI: 10.1016/j.celrep.2020.01.030] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 11/08/2019] [Accepted: 01/08/2020] [Indexed: 12/21/2022] Open
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Rai RC. Host inflammatory responses to intracellular invaders: Review study. Life Sci 2019; 240:117084. [PMID: 31759040 DOI: 10.1016/j.lfs.2019.117084] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2019] [Revised: 11/14/2019] [Accepted: 11/15/2019] [Indexed: 12/13/2022]
Abstract
As soon as a pathogen invades through the physical barriers of its corresponding host, host mounts a series of protective immune response to get rid of the invading pathogen. Host's pattern recognition receptors (PRR), localized at the cellular surface, cytoplasm and also in the nucleus; recognises pathogen associated molecular patterns (PAMPs) and plays crucial role in directing the immune response to be specific. Inflammatory responses are among the earliest strategies to tackle the pathogen by the host and are tightly regulated by multiple molecular pathways. Inflammasomes are multi-subunit protein complex consisting of a receptor molecule viz. NLRP3, an adaptor molecule- Apoptosis-associated speck-like protein containing a CARD (ASC) and an executioner caspase. Upon infection and/or injury; inflammasome components assemble and oligomerizes leading to the auto cleavage of the pro-caspase-1 to its active form. The activated caspase-1 cleaves immature form of the pro-inflammatory cytokines to their mature form e.g. IL1-β and IL-18 which mount inflammatory response. Moreover, C-terminal end of the Gasdermin D molecule is also cleaved by the caspase-1. The activated N-terminal Gasdermin D molecule form pores in the infected cells leading to their pyroptosis. Hence, inflammasomes drive inflammation during infection and controls the establishment of the pathogen by mounting inflammatory response and activation of the pyroptotic cell death.
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Affiliation(s)
- Ramesh Chandra Rai
- International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi 110067, India.
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Silveira FT. What makes mucosal and anergic diffuse cutaneous leishmaniases so clinically and immunopathogically different? A review in Brazil. Trans R Soc Trop Med Hyg 2019; 113:505-516. [PMID: 31140559 DOI: 10.1093/trstmh/trz037] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Revised: 03/21/2019] [Accepted: 04/22/2019] [Indexed: 11/14/2022] Open
Abstract
American cutaneous leishmaniasis (ACL) is a parasitic protozoan disease caused by different Leishmania species widely distributed throughout Latin America. Fifteen Leishmania species belonging to the subgenera Viannia, Leishmania and Mundinia are known to cause ACL. Seven of these species are found in Brazil, of which Leishmania (Viannia) braziliensis and Leishmania (Leishmania) amazonensis have the highest potential to cause mucosal (ML) and anergic diffuse cutaneous leishmaniasis (DCL), respectively, the most severe forms of ACL. The clinical and immunopathological differences between these two clinical forms are reviewed here, taking into account their different physiopathogenic mechanisms of dissemination from cutaneous lesions to mucosal tissues in the case of ML and to almost all body surfaces in the case of anergic DCL. We also discuss some immunopathogenic mechanisms of species-specific Leishmania antigens (from the subgenera Viannia and Leishmania) that are most likely associated with the clinical and immunopathological differences between ML and anergic DCL. Those discussions emphasize the pivotal importance of some surface antigens of L. (V.) braziliensis and L. (L.) amazonensis, such as lipophosphoglycan, phosphatidylserine and CD200 (an immunoregulatory molecule that inhibits macrophage activation), that have been shown to exert strong influences on the clinical and immunopathological differences between ML and anergic DCL.
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Affiliation(s)
- Fernando T Silveira
- Leishmaniasis Laboratory Prof. Dr. Ralph Lainson, Parasitology Department, Evandro Chagas Institute, Rod. BR 316-KM 07, Levilândia, Ananindeua, Pará State, Brazil
- Nucleus of Tropical Medicine, Federal University of Pará, Belém, Pará State, Brazil
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Gupta G, Santana AK, Gomes CM, Turatti A, Milanezi CM, Bueno Filho R, Fuzo C, Almeida RP, Carregaro V, Roselino AM, Silva JS. Inflammasome gene expression is associated with immunopathology in human localized cutaneous leishmaniasis. Cell Immunol 2019; 341:103920. [DOI: 10.1016/j.cellimm.2019.04.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Revised: 04/04/2019] [Accepted: 04/19/2019] [Indexed: 12/22/2022]
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Lugrin J, Martinon F. The AIM2 inflammasome: Sensor of pathogens and cellular perturbations. Immunol Rev 2017; 281:99-114. [DOI: 10.1111/imr.12618] [Citation(s) in RCA: 178] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Jérôme Lugrin
- Service of Adult Intensive Care Medicine; Lausanne University Hospital; Epalinges Switzerland
| | - Fabio Martinon
- Department of Biochemistry; University of Lausanne; Epalinges Switzerland
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IL-1β Production by Intermediate Monocytes Is Associated with Immunopathology in Cutaneous Leishmaniasis. J Invest Dermatol 2017; 138:1107-1115. [PMID: 29246797 DOI: 10.1016/j.jid.2017.11.029] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Revised: 11/21/2017] [Accepted: 11/22/2017] [Indexed: 01/10/2023]
Abstract
Cutaneous leishmaniasis due to Leishmania braziliensis infection is an inflammatory disease in which skin ulcer development is associated with mononuclear cell infiltrate and high levels of inflammatory cytokine production. Recently, NLRP3 inflammasome activation and IL-1β production have been associated with increased pathology in murine cutaneous leishmaniasis. We hypothesized that cutaneous leishmaniasis patients have increased expression of NLRP3, leading to high levels of IL-1β production. In this article we show high production of IL-1β in biopsy samples and Leishmania antigen-stimulated peripheral blood mononuclear cells from patients infected with L. braziliensis and reduced IL-1β levels after cure. IL-1β production positively correlated with the area of necrosis in lesions and duration of the lesions. The main source of IL-1β was intermediate monocytes (CD14++CD16+). Furthermore, our murine experiments show that IL-1β production in response to L. braziliensis was dependent on NLRP3, caspase-1, and caspase-recruiting domain (ASC). Additionally, we observed an increased expression of the NLRP3 gene in macrophages and the NLRP3 protein in intermediate monocytes from cutaneous leishmaniasis patients. These results identify an important role for human intermediate monocytes in the production of IL-1β, which contributes to the immunopathology observed in cutaneous leishmaniasis patients.
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