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Duszenko N, van Schuijlenburg R, Chevalley-Maurel S, van Willigen DM, de Bes-Roeleveld L, van der Wees S, Naar C, Baalbergen E, Heieis G, Bunschoten A, Velders AH, Franke-Fayard B, van Leeuwen FWB, Roestenberg M. Chemically augmented malaria sporozoites display an altered immunogenic profile. Front Immunol 2023; 14:1204606. [PMID: 37720224 PMCID: PMC10500441 DOI: 10.3389/fimmu.2023.1204606] [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: 04/12/2023] [Accepted: 07/25/2023] [Indexed: 09/19/2023] Open
Abstract
Despite promising results in malaria-naïve individuals, whole sporozoite (SPZ) vaccine efficacy in malaria-endemic settings has been suboptimal. Vaccine hypo-responsiveness due to previous malaria exposure has been posited as responsible, indicating the need for SPZ vaccines of increased immunogenicity. To this end, we here demonstrate a proof-of-concept for altering SPZ immunogenicity, where supramolecular chemistry enables chemical augmentation of the parasite surface with a TLR7 agonist-based adjuvant (SPZ-SAS(CL307)). In vitro, SPZ-SAS(CL307) remained well recognized by immune cells and induced a 35-fold increase in the production of pro-inflammatory IL-6 (p < 0.001). More promisingly, immunization of mice with SPZ-SAS(CL307) yielded improved SPZ-specific IFN-γ production in liver-derived NK cells (percentage IFN-γ+ cells 11.1 ± 1.8 vs. 9.4 ± 1.5%, p < 0.05), CD4+ T cells (4.7 ± 4.3 vs. 1.8 ± 0.7%, p < 0.05) and CD8+ T cells (3.6 ± 1.4 vs. 2.5 ± 0.9%, p < 0.05). These findings demonstrate the potential of using chemical augmentation strategies to enhance the immunogenicity of SPZ-based malaria vaccines.
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Affiliation(s)
- Nikolas Duszenko
- Department of Parasitology, Leiden University Medical Center, Leiden, Netherlands
- Interventional Molecular Imaging Laboratory, Department of Radiology, Leiden University Medical Center, Leiden, Netherlands
| | | | | | - Danny M. van Willigen
- Interventional Molecular Imaging Laboratory, Department of Radiology, Leiden University Medical Center, Leiden, Netherlands
| | | | | | - Chanel Naar
- Department of Parasitology, Leiden University Medical Center, Leiden, Netherlands
| | - Els Baalbergen
- Department of Parasitology, Leiden University Medical Center, Leiden, Netherlands
| | - Graham Heieis
- Department of Parasitology, Leiden University Medical Center, Leiden, Netherlands
| | - Anton Bunschoten
- Laboratory of BioNanoTechnology, Wageningen University & Research, Wageningen, Netherlands
| | - Aldrik H. Velders
- Laboratory of BioNanoTechnology, Wageningen University & Research, Wageningen, Netherlands
| | | | - Fijs W. B. van Leeuwen
- Interventional Molecular Imaging Laboratory, Department of Radiology, Leiden University Medical Center, Leiden, Netherlands
| | - Meta Roestenberg
- Department of Parasitology, Leiden University Medical Center, Leiden, Netherlands
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2
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Pandey SK, Anand U, Siddiqui WA, Tripathi R. Drug Development Strategies for Malaria: With the Hope for New Antimalarial Drug Discovery—An Update. Adv Med 2023; 2023:5060665. [PMID: 36960081 PMCID: PMC10030226 DOI: 10.1155/2023/5060665] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Revised: 02/27/2023] [Accepted: 03/08/2023] [Indexed: 03/15/2023] Open
Abstract
Malaria continued to be a deadly situation for the people of tropical and subtropical countries. Although there has been a marked reduction in new cases as well as mortality and morbidity rates in the last two decades, the reporting of malaria caused 247 million cases and 619000 deaths worldwide in 2021, according to the WHO (2022). The development of drug resistance and declining efficacy against most of the antimalarial drugs/combination in current clinical practice is a big challenge for the scientific community, and in the absence of an effective vaccine, the problem becomes worse. Experts from various research organizations worldwide are continuously working hard to stop this disaster by employing several strategies for the development of new antimalarial drugs/combinations. The current review focuses on the history of antimalarial drug discovery and the advantages, loopholes, and opportunities associated with the common strategies being followed for antimalarial drug development.
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Affiliation(s)
- Swaroop Kumar Pandey
- 1Department of Life Sciences, The National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
| | - Uttpal Anand
- 2Department of Life Sciences, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
| | - Waseem A. Siddiqui
- 3Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh 202001, Uttar Pradesh, India
| | - Renu Tripathi
- 4Department of Molecular Microbiology and Immunology, CSIR-Central Drug Research Institute, Lucknow 226031, Uttar Pradesh, India
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3
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Creation and preclinical evaluation of genetically attenuated malaria parasites arresting growth late in the liver. NPJ Vaccines 2022; 7:139. [PMCID: PMC9636417 DOI: 10.1038/s41541-022-00558-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Accepted: 10/13/2022] [Indexed: 11/06/2022] Open
Abstract
AbstractWhole-sporozoite (WSp) malaria vaccines induce protective immune responses in animal malaria models and in humans. A recent clinical trial with a WSp vaccine comprising genetically attenuated parasites (GAP) which arrest growth early in the liver (PfSPZ-GA1), showed that GAPs can be safely administered to humans and immunogenicity is comparable to radiation-attenuated PfSPZ Vaccine. GAPs that arrest late in the liver stage (LA-GAP) have potential for increased potency as shown in rodent malaria models. Here we describe the generation of four putative P. falciparum LA-GAPs, generated by CRISPR/Cas9-mediated gene deletion. One out of four gene-deletion mutants produced sporozoites in sufficient numbers for further preclinical evaluation. This mutant, PfΔmei2, lacking the mei2-like RNA gene, showed late liver growth arrest in human liver-chimeric mice with human erythrocytes, absence of unwanted genetic alterations and sensitivity to antimalarial drugs. These features of PfΔmei2 make it a promising vaccine candidate, supporting further clinical evaluation. PfΔmei2 (GA2) has passed regulatory approval for safety and efficacy testing in humans based on the findings reported in this study.
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4
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ICOS expression is required for maintenance but not the formation of germinal centers in the spleen in response to P. yoelii infection. Infect Immun 2022; 90:e0046821. [PMID: 35007126 DOI: 10.1128/iai.00468-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Inducible T cell co-stimulator (ICOS) plays a key role in the differentiation and maintenance of follicular helper T (Tfh) cells and thus germinal center (GC) formation. Previously, our lab showed in a Plasmodium chabaudi infection model that Icos-/- mice were significantly impaired in their ability to form GCs despite a persistent infection and thus a continued antigen (Ag) load. Here, we show that resolution of a primary infection with P. yoelii, was delayed in Icos-/- mice. This phenotype was associated with a reduction in the accumulation of Tfh-like and GC Tfh cells and an early deficiency in Ag-specific antibody (Ab) production. However, Icos-/- mice could form GCs, though they were less frequent in number than in wild-type (WT) mice. Nonetheless, the Ag-specific Abs from Icos-/- mice lacked signs of affinity maturation, suggesting functional defects associated with these GCs. Eventually, these GC structures dissipated more rapidly in Icos-/- mice than in WT mice. Moreover, the ability of Icos-/- mice to form these GC structures is not reliant on the high Ag load associated with P. yoelii infections, as GC formation was preserved in Icos-/- mice treated with atovaquone. Finally, mice were unable to form secondary GCs in the absence of ICOS after re-challenge. Overall, these data demonstrate the necessity of ICOS in the maintenance of Tfh cells, the formation and maintenance of sufficient numbers of functioning GCs, and the ability to generate new GC structures after re-infection with P. yoelii.
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5
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Ghilas S, Enders MH, May R, Holz LE, Fernandez-Ruiz D, Cozijnsen A, Mollard V, Cockburn IA, McFadden GI, Heath WR, Beattie L. Development of Plasmodium-specific liver-resident memory CD8 + T cells after heat-killed sporozoite immunization in mice. Eur J Immunol 2021; 51:1153-1165. [PMID: 33486759 DOI: 10.1002/eji.202048757] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 11/23/2020] [Accepted: 01/21/2021] [Indexed: 11/09/2022]
Abstract
Malaria remains a major cause of mortality in the world and an efficient vaccine is the best chance of reducing the disease burden. Vaccination strategies for the liver stage of disease that utilise injection of live radiation-attenuated sporozoites (RAS) confer sterile immunity, which is mediated by CD8+ memory T cells, with liver-resident memory T cells (TRM ) being particularly important. We have previously described a TCR transgenic mouse, termed PbT-I, where all CD8+ T cells recognize a specific peptide from Plasmodium. PbT-I form liver TRM cells upon RAS injection and are capable of protecting mice against challenge infection. Here, we utilize this transgenic system to examine whether nonliving sporozoites, killed by heat treatment (HKS), could trigger the development of Plasmodium-specific liver TRM cells. We found that HKS vaccination induced the formation of memory CD8+ T cells in the spleen and liver, and importantly, liver TRM cells were fewer in number than that induced by RAS. Crucially, we showed the number of TRM cells was significantly higher when HKS were combined with the glycolipid α-galactosylceramide as an adjuvant. In the future, this work could lead to development of an antimalaria vaccination strategy that does not require live sporozoites, providing greater utility.
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Affiliation(s)
- Sonia Ghilas
- Department of Microbiology and Immunology, University of Melbourne, at the Peter Doherty Institute for Infection and Immunity, Melbourne, VIC, 3000, Australia.,Australian Research Council Centre of Excellence in Advanced Molecular Imaging, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Matthias H Enders
- Department of Microbiology and Immunology, University of Melbourne, at the Peter Doherty Institute for Infection and Immunity, Melbourne, VIC, 3000, Australia.,Australian Research Council Centre of Excellence in Advanced Molecular Imaging, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Rose May
- Department of Microbiology and Immunology, University of Melbourne, at the Peter Doherty Institute for Infection and Immunity, Melbourne, VIC, 3000, Australia.,Australian Research Council Centre of Excellence in Advanced Molecular Imaging, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Lauren E Holz
- Department of Microbiology and Immunology, University of Melbourne, at the Peter Doherty Institute for Infection and Immunity, Melbourne, VIC, 3000, Australia.,Australian Research Council Centre of Excellence in Advanced Molecular Imaging, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Daniel Fernandez-Ruiz
- Department of Microbiology and Immunology, University of Melbourne, at the Peter Doherty Institute for Infection and Immunity, Melbourne, VIC, 3000, Australia.,Australian Research Council Centre of Excellence in Advanced Molecular Imaging, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Anton Cozijnsen
- School of BioSciences, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Vanessa Mollard
- School of BioSciences, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Ian A Cockburn
- John Curtin School of Medical Research, The Australian National University, Canberra, ACT, 2600, Australia
| | - Geoffrey I McFadden
- School of BioSciences, University of Melbourne, Parkville, VIC, 3010, Australia
| | - William R Heath
- Department of Microbiology and Immunology, University of Melbourne, at the Peter Doherty Institute for Infection and Immunity, Melbourne, VIC, 3000, Australia.,Australian Research Council Centre of Excellence in Advanced Molecular Imaging, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Lynette Beattie
- Department of Microbiology and Immunology, University of Melbourne, at the Peter Doherty Institute for Infection and Immunity, Melbourne, VIC, 3000, Australia.,Australian Research Council Centre of Excellence in Advanced Molecular Imaging, University of Melbourne, Parkville, VIC, 3010, Australia
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6
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Patra KP, Kaur H, Kolli SK, Wozniak JM, Prieto JH, Yates JR, Gonzalez DJ, Janse CJ, Vinetz JM. A Hetero-Multimeric Chitinase-Containing Plasmodium falciparum and Plasmodium gallinaceum Ookinete-Secreted Protein Complex Involved in Mosquito Midgut Invasion. Front Cell Infect Microbiol 2021; 10:615343. [PMID: 33489941 PMCID: PMC7821095 DOI: 10.3389/fcimb.2020.615343] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Accepted: 11/30/2020] [Indexed: 12/14/2022] Open
Abstract
Malaria parasites are transmitted by Anopheles mosquitoes. During its life cycle in the mosquito vector the Plasmodium ookinete escapes the proteolytic milieu of the post-blood meal midgut by traversing the midgut wall. This process requires penetration of the chitin-containing peritrophic matrix lining the midgut epithelium, which depends in part on ookinete-secreted chitinases. Plasmodium falciparum ookinetes have one chitinase (PfCHT1), whereas ookinetes of the avian-infecting parasite, P. gallinaceum, have two, a long and a short form, PgCHT1 and PgCHT2, respectively. Published data indicates that PgCHT2 forms a high molecular weight (HMW) reduction-sensitive complex; and one binding partner is the ookinete-produced von Willebrand A-domain-containing protein, WARP. Size exclusion chromatography data reported here show that P. gallinaceum PgCHT2 and its ortholog, P. falciparum PfCHT1 are covalently-linked components of a HMW chitinase-containing complex (> 1,300 kDa). Mass spectrometry of ookinete-secreted proteins isolated using a new chitin bead pull-down method identified chitinase-associated proteins in P. falciparum and P. gallinaceum ookinete-conditioned culture media. Mass spectrometry of this complex showed the presence of several micronemal proteins including von Willebrand factor A domain-related protein (WARP), ookinete surface enolase, and secreted ookinete adhesive protein (SOAP). To test the hypothesis that ookinete-produced PfCHT1 can form a high molecular homo-multimer or, alternatively, interacts with P. berghei ookinete-produced proteins to produce an HMW hetero-multimer, we created chimeric P. berghei parasites expressing PfCHT1 to replace PbCHT1, enabling the production of large numbers of PfCHT1-expressing ookinetes. We show that chimeric P. berghei ookinetes express monomeric PfCHT1, but a HMW complex containing PfCHT1 is not present. A better understanding of the chitinase-containing HMW complex may enhance development of next-generation vaccines or drugs that target malaria transmission stages.
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Affiliation(s)
- Kailash P Patra
- Section of Infectious Diseases, Department of Internal Medicine, Yale School of Medicine, New Haven, CT, United States
| | - Hargobinder Kaur
- Section of Infectious Diseases, Department of Internal Medicine, Yale School of Medicine, New Haven, CT, United States
| | - Surendra Kumar Kolli
- Department of Parasitology, Leiden University Medical Center, Leiden, Netherlands
| | - Jacob M Wozniak
- Department of Pharmacology and the Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA, United States
| | - Judith Helena Prieto
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, United States.,Department of Chemistry, Western Connecticut State University, Danbury, CT, United States
| | - John R Yates
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, United States
| | - David J Gonzalez
- Department of Pharmacology and the Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA, United States
| | - Chris J Janse
- Department of Parasitology, Leiden University Medical Center, Leiden, Netherlands
| | - Joseph M Vinetz
- Section of Infectious Diseases, Department of Internal Medicine, Yale School of Medicine, New Haven, CT, United States
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7
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Cai C, Hu Z, Yu X. Accelerator or Brake: Immune Regulators in Malaria. Front Cell Infect Microbiol 2020; 10:610121. [PMID: 33363057 PMCID: PMC7758250 DOI: 10.3389/fcimb.2020.610121] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Accepted: 11/09/2020] [Indexed: 12/15/2022] Open
Abstract
Malaria is a life-threatening infectious disease, affecting over 250 million individuals worldwide each year, eradicating malaria has been one of the greatest challenges to public health for a century. Growing resistance to anti-parasitic therapies and lack of effective vaccines are major contributing factors in controlling this disease. However, the incomplete understanding of parasite interactions with host anti-malaria immunity hinders vaccine development efforts to date. Recent studies have been unveiling the complexity of immune responses and regulators against Plasmodium infection. Here, we summarize our current understanding of host immune responses against Plasmodium-derived components infection and mainly focus on the various regulatory mechanisms mediated by recent identified immune regulators orchestrating anti-malaria immunity.
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Affiliation(s)
- Chunmei Cai
- Research Center for High Altitude Medicine, School of Medical, Qinghai University, Xining, China
- Key Laboratory of Application and Foundation for High Altitude Medicine Research in Qinghai Province, Qinghai University, Xining, China
| | - Zhiqiang Hu
- Department of Immunology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
| | - Xiao Yu
- Department of Immunology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
- Guangdong Provincial Key Lab of Single Cell Technology and Application, Southern Medical University, Guangzhou, China
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8
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Beyranvand Nejad E, Labrie C, Abdulrahman Z, van Elsas MJ, Rademaker E, Kleinovink JW, van der Sluis TC, van Duikeren S, Teunisse AFAS, Jochemsen AG, Oosting J, de Miranda NFCC, Van Hall T, Arens R, van der Burg SH. Lack of myeloid cell infiltration as an acquired resistance strategy to immunotherapy. J Immunother Cancer 2020; 8:jitc-2020-001326. [PMID: 32873723 PMCID: PMC7467529 DOI: 10.1136/jitc-2020-001326] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/06/2020] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Immunotherapy of cancer is successful but tumor regression often is incomplete and followed by escape. Understanding the mechanisms underlying this acquired resistance will aid the development of more effective treatments. METHODS We exploited a mouse model where tumor-specific therapeutic vaccination results in tumor regression, followed by local recurrence and resistance. In depth studies on systemic, local and tumor intrinsic changes were performed with flow and mass cytometry, immunohistochemistry, transcriptomics and several perturbation studies with inhibitors or agonistic antibodies in mice. Main findings were recapitulated in vaccinated patients. RESULTS Full tumor regression and cure of tumor-bearing mice is dependent on the magnitude of the vaccine-induced T-cell response. Recurrence of tumors did not involve classical immune escape mechanisms, such as antigen-presentation alterations, immune checkpoint expression, resistance to killing or local immune suppression. However, the recurrent tumors displayed a changed transcriptome with alterations in p53, tumor necrosis factor-α and transforming growth factor-β signaling pathways and they became immunologically cold. Remarkably, ex vivo cell-sorted recurrent tumors, directly reinjected in naïve hosts retained their resistance to vaccination despite a strong infiltration with tumor-specific CD8+ T cells, similar to that of vaccine-responsive tumors. The influx of inflammatory mature myeloid effector cells in the resistant tumors, however, was impaired and this turned out to be the underlying mechanisms as restoration of inflammatory myeloid cell infiltration reinstated the sensitivity of these refractory tumors to vaccination. Notably, impaired myeloid cell infiltration after vaccination was also associated with vaccine resistance in patients. CONCLUSION An immunotherapy-induced disability of tumor cells to attract innate myeloid effector cells formed a major mechanism underlying immune escape and acquired resistance. These data not only stresses the importance of myeloid effector cells during immunotherapy but also demands for new studies to harness their tumoricidal activities.
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Affiliation(s)
- Elham Beyranvand Nejad
- Oncode institute, Medical Oncology, Leiden University Medical Center, Leiden, The Netherlands
| | - Camilla Labrie
- Oncode institute, Medical Oncology, Leiden University Medical Center, Leiden, The Netherlands
| | - Ziena Abdulrahman
- Oncode institute, Medical Oncology, Leiden University Medical Center, Leiden, The Netherlands
| | - Marit J van Elsas
- Oncode institute, Medical Oncology, Leiden University Medical Center, Leiden, The Netherlands
| | - Eva Rademaker
- Pathology, Leiden University Medical Center, Leiden, The Netherlands
| | - Jan Willem Kleinovink
- Oncode institute, Medical Oncology, Leiden University Medical Center, Leiden, The Netherlands
| | - Tetje C van der Sluis
- Immunohematology and Bloodtransfusion, Leiden Universitair Medisch Centrum, Leiden, The Netherlands
| | - Suzanne van Duikeren
- Immunohematology and Bloodtransfusion, Leiden Universitair Medisch Centrum, Leiden, The Netherlands
| | - Amina F A S Teunisse
- Cell and Chemical Biology, Leiden University Medical Center, Leiden, The Netherlands
| | - Aart G Jochemsen
- Cell and Chemical Biology, Leiden University Medical Center, Leiden, The Netherlands
| | - Jan Oosting
- Pathology, Leiden University Medical Center, Leiden, The Netherlands
| | | | - Thorbald Van Hall
- Oncode institute, Medical Oncology, Leiden University Medical Center, Leiden, The Netherlands
| | - Ramon Arens
- Immunohematology and Bloodtransfusion, Leiden Universitair Medisch Centrum, Leiden, The Netherlands
| | - Sjoerd H van der Burg
- Oncode institute, Medical Oncology, Leiden University Medical Center, Leiden, The Netherlands
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9
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Faleiro R, Karunarathne DS, Horne-Debets JM, Wykes M. The Contribution of Co-signaling Pathways to Anti-malarial T Cell Immunity. Front Immunol 2018; 9:2926. [PMID: 30631323 PMCID: PMC6315188 DOI: 10.3389/fimmu.2018.02926] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Accepted: 11/29/2018] [Indexed: 12/30/2022] Open
Abstract
Plasmodium spp., the causative agent of malaria, caused 212 million infections in 2016 with 445,000 deaths, mostly in children. Adults acquire enough immunity to prevent clinical symptoms but never develop sterile immunity. The only vaccine for malaria, RTS,S, shows promising protection of a limited duration against clinical malaria in infants but no significant protection against severe disease. There is now abundant evidence that T cell functions are inhibited during malaria, which may explain why vaccine are not efficacious. Studies have now clearly shown that T cell immunity against malaria is subdued by multiple the immune regulatory receptors, in particular, by programmed cell-death-1 (PD-1). Given there is an urgent need for an efficacious malarial treatment, compounded with growing drug resistance, a better understanding of malarial immunity is essential. This review will examine molecular signals that affect T cell-mediated immunity against malaria.
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Affiliation(s)
- Rebecca Faleiro
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia
| | | | | | - Michelle Wykes
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia
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