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Azad MTA, Sugi T, Qulsum U, Kato K. Detection of Developmental Asexual Stage-Specific RNA Editing Events in Plasmodium falciparum 3D7 Malaria Parasite. Microorganisms 2024; 12:137. [PMID: 38257964 PMCID: PMC10819399 DOI: 10.3390/microorganisms12010137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Revised: 12/24/2023] [Accepted: 12/30/2023] [Indexed: 01/24/2024] Open
Abstract
Transcriptional variation has been studied but post-transcriptional modification due to RNA editing has not been investigated in Plasmodium. We investigated developmental stage-specific RNA editing in selected genes in Plasmodium falciparum 3D7. We detected extensive amination- and deamination-type RNA editing at 8, 16, 24, 32, 40, and 46 h in tightly synchronized Plasmodium. Most of the editing events were observed in 8 and 16 h ring-stage parasites. Extensive A-to-G deamination-type editing was detected more during the 16 h ring stage (25%) than the 8 h ring stage (20%). Extensive U-to-C amination-type editing was detected more during the 16 h ring stage (31%) than the 8 h ring stage (22%). In 28S, rRNA editing converted the loop structure to the stem structure. The hemoglobin binding activity of PF3D7_0216900 was also altered due to RNA editing. Among the expressed 28S rRNA genes, PF3D7_0532000 and PF3D7_0726000 expression was higher. Increased amounts of the transcripts of these two genes were found, particularly PF3D7_0726000 in the ring stage and PF3D7_0532000 in the trophozoite and schizont stages. Adenosine deaminase (ADA) expression did not correlate with the editing level. This first experimental report of RNA editing will help to identify the editing machinery that might be useful for antimalarial drug discovery and malaria control.
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Affiliation(s)
- Md Thoufic Anam Azad
- Laboratory of Sustainable Animal Environment, Graduate School of Agricultural Science, Tohoku University, 232-3 Yomogida, Naruko-onsen, Osaki, Miyagi 989-6711, Japan
- Department of Veterinary and Animal Sciences, University of Rajshahi, Rajshahi 6205, Bangladesh
| | - Tatsuki Sugi
- Division of Collaboration and Education, International Institute for Zoonosis Control, Hokkaido University, Nishi10-Kita 20, Sapporo 001-0020, Japan
| | - Umme Qulsum
- Laboratory of Sustainable Animal Environment, Graduate School of Agricultural Science, Tohoku University, 232-3 Yomogida, Naruko-onsen, Osaki, Miyagi 989-6711, Japan
- Department of Botany, Faculty of Biological Sciences, University of Rajshahi, Rajshahi 6205, Bangladesh
| | - Kentaro Kato
- Laboratory of Sustainable Animal Environment, Graduate School of Agricultural Science, Tohoku University, 232-3 Yomogida, Naruko-onsen, Osaki, Miyagi 989-6711, Japan
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Anand A, Chandana M, Ghosh S, Das R, Singh N, Vaishalli PM, Gantasala NP, Padmanaban G, Nagaraj VA. Significance of Plasmodium berghei Amino Acid Transporter 1 in Food Vacuole Functionality and Its Association with Cerebral Pathogenesis. Microbiol Spectr 2023; 11:e0494322. [PMID: 36976018 PMCID: PMC10101031 DOI: 10.1128/spectrum.04943-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Accepted: 03/07/2023] [Indexed: 03/29/2023] Open
Abstract
The food vacuole plays a central role in the blood stage of parasite development by digesting host hemoglobin acquired from red blood cells and detoxifying the host heme released during hemoglobin digestion into hemozoin. Blood-stage parasites undergo periodic schizont bursts, releasing food vacuoles containing hemozoin. Clinical studies in malaria-infected patients and in vivo animal studies have shown the association of hemozoin with disease pathogenesis and abnormal host immune responses in malaria. Here, we perform a detailed in vivo characterization of putative Plasmodium berghei amino acid transporter 1 localized in the food vacuole to understand its significance in the malaria parasite. We show that the targeted deletion of amino acid transporter 1 in Plasmodium berghei leads to a swollen food vacuole phenotype with the accumulation of host hemoglobin-derived peptides. Plasmodium berghei amino acid transporter 1-knockout parasites produce less hemozoin, and the hemozoin crystals display a thin morphology compared with wild-type parasites. The knockout parasites show reduced sensitivity to chloroquine and amodiaquine by showing recrudescence. More importantly, mice infected with the knockout parasites are protected from cerebral malaria and display reduced neuronal inflammation and cerebral complications. Genetic complementation of the knockout parasites restores the food vacuole morphology with hemozoin levels similar to that of wild-type parasites, causing cerebral malaria in the infected mice. The knockout parasites also show a significant delay in male gametocyte exflagellation. Our findings highlight the significance of amino acid transporter 1 in food vacuole functionality and its association with malaria pathogenesis and gametocyte development. IMPORTANCE Food vacuoles of the malaria parasite are involved in the degradation of red blood cell hemoglobin. The amino acids derived from hemoglobin degradation support parasite growth, and the heme released is detoxified into hemozoin. Antimalarials such as quinolines target hemozoin formation in the food vacuole. Food vacuole transporters transport hemoglobin-derived amino acids and peptides from the food vacuole to the parasite cytosol. Such transporters are also associated with drug resistance. Here, we show that the deletion of amino acid transporter 1 in Plasmodium berghei leads to swollen food vacuoles with the accumulation of hemoglobin-derived peptides. The transporter-deleted parasites generate less hemozoin with thin crystal morphology and show reduced sensitivity to quinolines. Mice infected with transporter-deleted parasites are protected from cerebral malaria. There is also a delay in male gametocyte exflagellation, affecting transmission. Our findings uncover the functional significance of amino acid transporter 1 in the life cycle of the malaria parasite.
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Affiliation(s)
- Aditya Anand
- Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, Odisha, India
- Regional Centre for Biotechnology, Faridabad, Haryana, India
| | - Manjunatha Chandana
- Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, Odisha, India
- School of Biotechnology, Kalinga Institute of Industrial Technology, Bhubaneswar, Odisha, India
| | - Sourav Ghosh
- Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, Odisha, India
- Regional Centre for Biotechnology, Faridabad, Haryana, India
| | - Rahul Das
- Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, Odisha, India
- Regional Centre for Biotechnology, Faridabad, Haryana, India
| | - Nalini Singh
- Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, Odisha, India
| | - Pradeep Mini Vaishalli
- Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, Odisha, India
- Regional Centre for Biotechnology, Faridabad, Haryana, India
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Storm J, Camarda G, Haley MJ, Brough D, Couper KN, Craig AG. Plasmodium falciparum-infected erythrocyte co-culture with the monocyte cell line THP-1 does not trigger production of soluble factors reducing brain microvascular barrier function. PLoS One 2023; 18:e0285323. [PMID: 37141324 PMCID: PMC10159134 DOI: 10.1371/journal.pone.0285323] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Accepted: 04/19/2023] [Indexed: 05/06/2023] Open
Abstract
Monocytes contribute to the pro-inflammatory immune response during the blood stage of a Plasmodium falciparum infection, but their precise role in malaria pathology is not clear. Besides phagocytosis, monocytes are activated by products from P. falciparum infected erythrocytes (IE) and one of the activation pathways is potentially the NLR family pyrin domain containing 3 (NLRP3) inflammasome, a multi-protein complex that leads to the production of interleukin (IL)-1β. In cerebral malaria cases, monocytes accumulate at IE sequestration sites in the brain microvascular and the locally produced IL-1β, or other secreted molecules, could contribute to leakage of the blood-brain barrier. To study the activation of monocytes by IE within the brain microvasculature in an in vitro model, we co-cultured IT4var14 IE and the monocyte cell line THP-1 for 24 hours and determined whether generated soluble molecules affect barrier function of human brain microvascular endothelial cells, measured by real time trans-endothelial electrical resistance. The medium produced after co-culture did not affect endothelial barrier function and similarly no effect was measured after inducing oxidative stress by adding xanthine oxidase to the co-culture. While IL-1β does decrease barrier function, barely any IL-1β was produced in the co- cultures, indicative of a lack of or incomplete THP-1 activation by IE in this co-culture model.
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Affiliation(s)
- Janet Storm
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Grazia Camarda
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Michael J Haley
- Division of Immunology, Immunity to Infection and Respiratory Medicine, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - David Brough
- Division of Neuroscience, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, United Kingdom
| | - Kevin N Couper
- Division of Immunology, Immunity to Infection and Respiratory Medicine, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - Alister G Craig
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
- Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
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Olatunde AC, Cornwall DH, Roedel M, Lamb TJ. Mouse Models for Unravelling Immunology of Blood Stage Malaria. Vaccines (Basel) 2022; 10:1525. [PMID: 36146602 PMCID: PMC9501382 DOI: 10.3390/vaccines10091525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2022] [Revised: 09/05/2022] [Accepted: 09/06/2022] [Indexed: 11/16/2022] Open
Abstract
Malaria comprises a spectrum of disease syndromes and the immune system is a major participant in malarial disease. This is particularly true in relation to the immune responses elicited against blood stages of Plasmodium-parasites that are responsible for the pathogenesis of infection. Mouse models of malaria are commonly used to dissect the immune mechanisms underlying disease. While no single mouse model of Plasmodium infection completely recapitulates all the features of malaria in humans, collectively the existing models are invaluable for defining the events that lead to the immunopathogenesis of malaria. Here we review the different mouse models of Plasmodium infection that are available, and highlight some of the main contributions these models have made with regards to identifying immune mechanisms of parasite control and the immunopathogenesis of malaria.
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Affiliation(s)
| | | | | | - Tracey J. Lamb
- Department of Pathology, University of Utah, Emma Eccles Jones Medical Research Building, 15 N Medical Drive E, Room 1420A, Salt Lake City, UT 84112, USA
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Dalapati T, Moore JM. Hemozoin: a Complex Molecule with Complex Activities. CURRENT CLINICAL MICROBIOLOGY REPORTS 2022; 8:87-102. [PMID: 35096512 DOI: 10.1007/s40588-021-00166-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Purpose of Review Malaria is a disease caused by parasites that reside in host red blood cells and use hemoglobin as a nutrient source. Heme released by hemoglobin catabolism is modified by the parasite to produce hemozoin (HZ), which has toxic effects on the host. Experimentation aiming to elucidate how HZ contributes to malaria pathogenesis has utilized different preparations of this molecule, complicating interpretation and comparison of findings. We examine natural synthesis and isolation of HZ and highlight studies that have used multiple preparations, including synthetic forms, in a comparative fashion. Recent Findings Recent work utilizing sophisticated imaging and detection techniques reveals important molecular characteristics of HZ synthesis and biochemistry. Other recent studies further refine understanding of contributions of HZ to malaria pathogenesis yet highlight the continuing need to characterize HZ preparations and contextualize experimental conditions in the in vivo infection milieu. Summary This review highlights the necessity of collectively determining what is physiologically relevant HZ. Characterization of isolated natural HZ and use of multiple preparations in each study are recommended with application of in vivo studies whenever possible. Adoption of such practices is expected to improve reproducibility of results and elucidate the myriad of ways that HZ participates in malaria pathogenesis.
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Affiliation(s)
- Trisha Dalapati
- Duke University School of Medicine, Duke University, Durham, NC, USA
| | - Julie M Moore
- Department of Infectious Diseases and Immunology, College of Veterinary Medicine, University of Florida, Gainesville, FL, USA
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Heme oxygenase-1, carbon monoxide, and malaria – The interplay of chemistry and biology. Coord Chem Rev 2022. [DOI: 10.1016/j.ccr.2021.214285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Fischer S, Stegmann F, Gnanapragassam VS, Lepenies B. From structure to function – Ligand recognition by myeloid C-type lectin receptors. Comput Struct Biotechnol J 2022; 20:5790-5812. [DOI: 10.1016/j.csbj.2022.10.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 10/14/2022] [Accepted: 10/14/2022] [Indexed: 11/29/2022] Open
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Possemiers H, Pham TT, Coens M, Pollenus E, Knoops S, Noppen S, Vandermosten L, D’haese S, Dillemans L, Prenen F, Schols D, Franke-Fayard B, Van den Steen PE. Skeleton binding protein-1-mediated parasite sequestration inhibits spontaneous resolution of malaria-associated acute respiratory distress syndrome. PLoS Pathog 2021; 17:e1010114. [PMID: 34843584 PMCID: PMC8659713 DOI: 10.1371/journal.ppat.1010114] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 12/09/2021] [Accepted: 11/15/2021] [Indexed: 11/18/2022] Open
Abstract
Malaria is a hazardous disease caused by Plasmodium parasites and often results in lethal complications, including malaria-associated acute respiratory distress syndrome (MA-ARDS). Parasite sequestration in the microvasculature is often observed, but its role in malaria pathogenesis and complications is still incompletely understood. We used skeleton binding protein-1 (SBP-1) KO parasites to study the role of sequestration in experimental MA-ARDS. The sequestration-deficiency of these SBP-1 KO parasites was confirmed with bioluminescence imaging and by measuring parasite accumulation in the lungs with RT-qPCR. The SBP-1 KO parasites induced similar lung pathology in the early stage of experimental MA-ARDS compared to wildtype (WT) parasites. Strikingly, the lung pathology resolved subsequently in more than 60% of the SBP-1 KO infected mice, resulting in prolonged survival despite the continuous presence of the parasite. This spontaneous disease resolution was associated with decreased inflammatory cytokine expression measured by RT-qPCR and lower expression of cytotoxic markers in pathogenic CD8+ T cells in the lungs of SBP-1 KO infected mice. These data suggest that SBP-1-mediated parasite sequestration and subsequent high parasite load are not essential for the development of experimental MA-ARDS but inhibit the resolution of the disease. Malaria is still a severe global disease with more than 200 million cases and 400 000 deaths each year. Plasmodium falciparum is the species responsible for most malaria deaths globally. The propensity of these parasites to sequester in peripheral vascular beds is assumed to play an important role in disease severity and mortality. Although sequestration has been observed in lungs of malaria patients, its role in the pathogenesis of MA-ARDS, a severe lung complication in malaria, was previously unknown. Therefore, we used sequestration-deficient SBP-1 KO Plasmodium berghei NK65 parasites to study the role of sequestration in experimental MA-ARDS. We observed that MA-ARDS developed similarly in WT and SBP-1 KO infected mice, but the majority of SBP-1 KO-infected mice were able to resolve the lung pathology despite the continuous presence of the parasite. This coincided with a prolonged survival, a decrease in inflammatory cytokine expression and lower expression of cytotoxicity markers in pathogenic CD8+ T cells. These results give important new insights in the role of parasite sequestration in malaria pathology.
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Affiliation(s)
- Hendrik Possemiers
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical research, KU Leuven, Belgium
| | - Thao-Thy Pham
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical research, KU Leuven, Belgium
- Currently at Clinical Immunology Unit, Department of Clinical Sciences, Institute of Tropical Medicine Antwerp, Belgium
| | - Marion Coens
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical research, KU Leuven, Belgium
| | - Emilie Pollenus
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical research, KU Leuven, Belgium
| | - Sofie Knoops
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical research, KU Leuven, Belgium
| | - Sam Noppen
- Laboratory of Virology and Chemotherapy, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical research, KU Leuven, Belgium
| | - Leen Vandermosten
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical research, KU Leuven, Belgium
| | - Sigrid D’haese
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical research, KU Leuven, Belgium
- Currently at Neuro-Aging & Viro-Immunotherapy (NAVI), Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Luna Dillemans
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical research, KU Leuven, Belgium
| | - Fran Prenen
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical research, KU Leuven, Belgium
| | - Dominique Schols
- Laboratory of Virology and Chemotherapy, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical research, KU Leuven, Belgium
| | | | - Philippe E. Van den Steen
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical research, KU Leuven, Belgium
- * E-mail:
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Olanlokun JO, Ekundayo MT, Ebenezer O, Koorbanally NA, Olorunsogo OO. Antimalarial and Erythrocyte Membrane Stability Properties of Globimetula braunii (Engle Van Tiegh) Growing on Cocoa in Plasmodium berghei-Infected Mice. Infect Drug Resist 2021; 14:3795-3808. [PMID: 34584427 PMCID: PMC8462095 DOI: 10.2147/idr.s317732] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 07/07/2021] [Indexed: 02/02/2023] Open
Abstract
Introduction Resistant malaria is a fatal disease. Globimetula braunii (African Mistletoe) is traditionally used for malarial treatment but this fact has not been scientifically reported. Methods Plasmodium berghei (NK65)-infected male Swiss mice (20±2 g) were treated orally and once daily with 100, 200, and 400 mg/kg BW of methanol extract and its respective hexane, dichloromethane and ethyl acetate fractions for 9 days. P-alaxin was used as control drug P. berghei (ANKA)-infected mice were then treated with the most potent fraction for 5 days. Parasitemia and parasite clearance were determined by microscopy, while hematological parameters, heme, hemozoin, and mouse erythrocyte membrane stabilisation were assayed. The phytochemicals in the most potent fraction were identified using gas chromatography-mass spectrometry. Results Hexane fraction (HF)-treated mice (400 mg/kg BW) had the least mean parasite load (0.00 ± 0.00; 0.14 ± 0.05%) and highest clearance (100 ± 0.00; 75.50 ± 4.95%) compared with infected control (9.81 ± 0.09; 6.84 ± 0.09%) in susceptible and resistant models, respectively. Hexane fraction modulated hematological indices, minimised erythrocyte membrane damage in heat-induced (2.18 ± 0.94%) and hypotonic solution-induced (7.93 ± 0.93%) compared to artequin (5.05 ± 2.18; 6.38 ± 0.33%) and P-alaxin (67.45 ± 5.15; 56.78 ± 1.10%) in both models of membrane stabilisation, respectively. Hexane fraction (P<0.01) increased heme and decreased hemozoin contents. Friedelan-3-one was identified as the most abundant triterpene. Conclusion The results indicated that G. braunii has anti-plasmodial properties and minimally dis-stabilised erythrocyte membrane. The major findings in this study are that n-hexane fraction of G. braunii possess excellent and moderate antiplasmodial activity against susceptible and resistant P. berghei, respectively. This was reflected via decreased parasite load, improved hematological parameters, increased heme and decreased hemozoin contents. Friedelan-3-one, a major constituent of the n-hexane fraction, may be responsible for this activity.
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Affiliation(s)
- John Oludele Olanlokun
- Laboratories for Biomembrane Research and Biotechnology, Faculty of Basic Medical Sciences, College of Medicine, University of Ibadan, Ibadan, 4000, Nigeria
| | - Mercy Toluwase Ekundayo
- Laboratories for Biomembrane Research and Biotechnology, Faculty of Basic Medical Sciences, College of Medicine, University of Ibadan, Ibadan, 4000, Nigeria
| | - Oluwakemi Ebenezer
- School of Chemistry and Physics, University of KwaZulu-Natal, Durban, 4006, South Africa
| | | | - Olufunso Olabode Olorunsogo
- Laboratories for Biomembrane Research and Biotechnology, Faculty of Basic Medical Sciences, College of Medicine, University of Ibadan, Ibadan, 4000, Nigeria
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Pack AD, Schwartzhoff PV, Zacharias ZR, Fernandez-Ruiz D, Heath WR, Gurung P, Legge KL, Janse CJ, Butler NS. Hemozoin-mediated inflammasome activation limits long-lived anti-malarial immunity. Cell Rep 2021; 36:109586. [PMID: 34433049 PMCID: PMC8432597 DOI: 10.1016/j.celrep.2021.109586] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 05/21/2021] [Accepted: 07/30/2021] [Indexed: 12/04/2022] Open
Abstract
During acute malaria, most individuals mount robust inflammatory responses that limit parasite burden. However, long-lived sterilizing anti-malarial memory responses are not efficiently induced, even following repeated Plasmodium exposures. Using multiple Plasmodium species, genetically modified parasites, and combinations of host genetic and pharmacologic approaches, we find that the deposition of the malarial pigment hemozoin directly limits the abundance and capacity of conventional type 1 dendritic cells to prime helper T cell responses. Hemozoin-induced dendritic cell dysfunction results in aberrant Plasmodium-specific CD4 T follicular helper cell differentiation, which constrains memory B cell and long-lived plasma cell formation. Mechanistically, we identify that dendritic cell-intrinsic NLRP3 inflammasome activation reduces conventional type 1 dendritic cell abundance, phagocytosis, and T cell priming functions in vivo. These data identify biological consequences of hemozoin deposition during malaria and highlight the capacity of the malarial pigment to program immune evasion during the earliest events following an initial Plasmodium exposure.
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Affiliation(s)
- Angela D Pack
- Department of Microbiology and Immunology, University of Iowa, Iowa City, IA, USA
| | | | - Zeb R Zacharias
- Department of Pathology, University of Iowa, Iowa City, IA, USA
| | - Daniel Fernandez-Ruiz
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, VIC 3000, Australia
| | - William R Heath
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, VIC 3000, Australia; ARC Centre of Excellence in Advanced Molecular Imaging, University of Melbourne, Parkville, VIC 3010, Australia
| | - Prajwal Gurung
- Department of Internal Medicine, University of Iowa, Iowa City, IA, USA; Interdisciplinary Graduate Program in Immunology, University of Iowa, Iowa City, IA, USA
| | - Kevin L Legge
- Department of Pathology, University of Iowa, Iowa City, IA, USA; Interdisciplinary Graduate Program in Immunology, University of Iowa, Iowa City, IA, USA
| | - Chris J Janse
- Leiden Malaria Research Group, Centre of Infectious Diseases, Leiden University Medical Centre, Leiden 233 ZA, the Netherlands
| | - Noah S Butler
- Department of Microbiology and Immunology, University of Iowa, Iowa City, IA, USA; Interdisciplinary Graduate Program in Immunology, University of Iowa, Iowa City, IA, USA.
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