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Nemphos SM, Green HC, Prusak JE, Fell SL, Goff K, Varnado M, Didier K, Guy N, Moström MJ, Tatum C, Massey C, Barnes MB, Rowe LA, Allers C, Blair RV, Embers ME, Maness NJ, Marx PA, Grasperge B, Kaur A, De Paris K, Shaffer JG, Hensley-McBain T, Londono-Renteria B, Manuzak JA. Elevated Inflammation Associated with Markers of Neutrophil Function and Gastrointestinal Disruption in Pilot Study of Plasmodium fragile Co-Infection of ART-Treated SIVmac239+ Rhesus Macaques. Viruses 2024; 16:1036. [PMID: 39066199 PMCID: PMC11281461 DOI: 10.3390/v16071036] [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: 05/16/2024] [Revised: 06/14/2024] [Accepted: 06/24/2024] [Indexed: 07/28/2024] Open
Abstract
Human immunodeficiency virus (HIV) and malaria, caused by infection with Plasmodium spp., are endemic in similar geographical locations. As a result, there is high potential for HIV/Plasmodium co-infection, which increases the pathology of both diseases. However, the immunological mechanisms underlying the exacerbated disease pathology observed in co-infected individuals are poorly understood. Moreover, there is limited data available on the impact of Plasmodium co-infection on antiretroviral (ART)-treated HIV infection. Here, we used the rhesus macaque (RM) model to conduct a pilot study to establish a model of Plasmodium fragile co-infection during ART-treated simian immunodeficiency virus (SIV) infection, and to begin to characterize the immunopathogenic effect of co-infection in the context of ART. We observed that P. fragile co-infection resulted in parasitemia and anemia, as well as persistently detectable viral loads (VLs) and decreased absolute CD4+ T-cell counts despite daily ART treatment. Notably, P. fragile co-infection was associated with increased levels of inflammatory cytokines, including monocyte chemoattractant protein 1 (MCP-1). P. fragile co-infection was also associated with increased levels of neutrophil elastase, a plasma marker of neutrophil extracellular trap (NET) formation, but significant decreases in markers of neutrophil degranulation, potentially indicating a shift in the neutrophil functionality during co-infection. Finally, we characterized the levels of plasma markers of gastrointestinal (GI) barrier permeability and microbial translocation and observed significant correlations between indicators of GI dysfunction, clinical markers of SIV and Plasmodium infection, and neutrophil frequency and function. Taken together, these pilot data verify the utility of using the RM model to examine ART-treated SIV/P. fragile co-infection, and indicate that neutrophil-driven inflammation and GI dysfunction may underlie heightened SIV/P. fragile co-infection pathogenesis.
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Affiliation(s)
- Sydney M. Nemphos
- Division of Immunology, Tulane National Primate Research Center, Covington, LA 70433, USA
| | - Hannah C. Green
- Division of Immunology, Tulane National Primate Research Center, Covington, LA 70433, USA
| | - James E. Prusak
- Division of Immunology, Tulane National Primate Research Center, Covington, LA 70433, USA
| | - Sallie L. Fell
- Division of Immunology, Tulane National Primate Research Center, Covington, LA 70433, USA
| | - Kelly Goff
- Division of Microbiology, Tulane National Primate Research Center, Covington, LA 70433, USA
| | - Megan Varnado
- Division of Immunology, Tulane National Primate Research Center, Covington, LA 70433, USA
| | - Kaitlin Didier
- Division of Immunology, Tulane National Primate Research Center, Covington, LA 70433, USA
| | - Natalie Guy
- Division of Immunology, Tulane National Primate Research Center, Covington, LA 70433, USA
| | - Matilda J. Moström
- Division of Immunology, Tulane National Primate Research Center, Covington, LA 70433, USA
| | - Coty Tatum
- Division of Microbiology, Tulane National Primate Research Center, Covington, LA 70433, USA
| | - Chad Massey
- Division of Immunology, Tulane National Primate Research Center, Covington, LA 70433, USA
| | - Mary B. Barnes
- Division of Microbiology, Tulane National Primate Research Center, Covington, LA 70433, USA
| | - Lori A. Rowe
- Division of Microbiology, Tulane National Primate Research Center, Covington, LA 70433, USA
| | - Carolina Allers
- Division of Immunology, Tulane National Primate Research Center, Covington, LA 70433, USA
| | - Robert V. Blair
- Division of Comparative Pathology, Tulane National Primate Research Center, Covington, LA 70433, USA
| | - Monica E. Embers
- Division of Immunology, Tulane National Primate Research Center, Covington, LA 70433, USA
| | - Nicholas J. Maness
- Division of Microbiology, Tulane National Primate Research Center, Covington, LA 70433, USA
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Preston A. Marx
- Division of Microbiology, Tulane National Primate Research Center, Covington, LA 70433, USA
- Department of Tropical Medicine and Infectious Disease, Tulane University School of Public Health and Tropical Medicine, New Orleans, LA 70112, USA;
| | - Brooke Grasperge
- Division of Veterinary Medicine, Tulane National Primate Research Center, Covington, LA 70433, USA
| | - Amitinder Kaur
- Division of Immunology, Tulane National Primate Research Center, Covington, LA 70433, USA
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Kristina De Paris
- Department of Microbiology and Immunology, University of North Carolina School of Medicine, Chapel Hill, NC 27559, USA
| | - Jeffrey G. Shaffer
- Department of Biostatistics and Data Science, Tulane University School of Public Health and Tropical Medicine, New Orleans, LA 70112, USA
| | | | - Berlin Londono-Renteria
- Department of Tropical Medicine and Infectious Disease, Tulane University School of Public Health and Tropical Medicine, New Orleans, LA 70112, USA;
| | - Jennifer A. Manuzak
- Division of Immunology, Tulane National Primate Research Center, Covington, LA 70433, USA
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, LA 70112, USA
- Department of Tropical Medicine and Infectious Disease, Tulane University School of Public Health and Tropical Medicine, New Orleans, LA 70112, USA;
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Vera IM, Kessler A, Harawa V, Ahmadu A, Keller TE, Ray ST, Taylor TE, Rogerson SJ, Mandala WL, Reyes Gil M, Seydel KB, Kim K. Prothrombotic autoantibodies targeting platelet factor 4/polyanion are associated with pediatric cerebral malaria. J Clin Invest 2024; 134:e176466. [PMID: 38652559 PMCID: PMC11142751 DOI: 10.1172/jci176466] [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: 10/10/2023] [Accepted: 04/09/2024] [Indexed: 04/25/2024] Open
Abstract
BACKGROUNDFeatures of consumptive coagulopathy and thromboinflammation are prominent in cerebral malaria (CM). We hypothesized that thrombogenic autoantibodies contribute to a procoagulant state in CM.METHODSPlasma from children with uncomplicated malaria (UM) (n = 124) and CM (n = 136) was analyzed by ELISA for a panel of 8 autoantibodies including anti-platelet factor 4/polyanion (anti-PF4/P), anti-phospholipid, anti-phosphatidylserine, anti-myeloperoxidase, anti-proteinase 3, anti-dsDNA, anti-β-2-glycoprotein I, and anti-cardiolipin. Plasma samples from individuals with nonmalarial coma (NMC) (n = 49) and healthy controls (HCs) (n = 56) were assayed for comparison. Associations with clinical and immune biomarkers were determined using univariate and logistic regression analyses.RESULTSMedian anti-PF4/P and anti-PS IgG levels were elevated in individuals with malaria infection relative to levels in HCs (P < 0.001) and patients with NMC (PF4/P: P < 0.001). Anti-PF4/P IgG levels were elevated in children with CM (median = 0.27, IQR: 0.19-0.41) compared with those with UM (median = 0.19, IQR: 0.14-0.22, P < 0.0001). Anti-PS IgG levels did not differ between patients with UM and those with CM (P = 0.39). When patients with CM were stratified by malaria retinopathy (Ret) status, the levels of anti-PF4/P IgG correlated negatively with the peripheral platelet count in patients with Ret+ CM (Spearman's rho [Rs] = 0.201, P = 0.04) and associated positively with mortality (OR = 15.2, 95% CI: 1.02-275, P = 0.048). Plasma from patients with CM induced greater platelet activation in an ex vivo assay relative to plasma from patients with UM (P = 0.02), and the observed platelet activation was associated with anti-PF4/P IgG levels (Rs= 0.293, P = 0.035).CONCLUSIONSThrombosis mediated by elevated anti-PF4/P autoantibodies may be one mechanism contributing to the clinical complications of CM.
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Affiliation(s)
- Iset M. Vera
- Division of Infectious Disease and International Medicine, Department of Internal Medicine, University of South Florida, Tampa, Florida, USA
| | - Anne Kessler
- Center for Genomics and Systems Biology, Department of Biology, New York University, New York, New York, USA
| | - Visopo Harawa
- Malawi-Liverpool Wellcome Trust Clinical Research Programme, Blantyre, Malawi
- Biomedical Department, University of Malawi College of Medicine, Blantyre, Malawi
- Blantyre Malaria Project, Kamuzu University of Health Sciences, Blantyre, Malawi
| | - Ajisa Ahmadu
- Malawi-Liverpool Wellcome Trust Clinical Research Programme, Blantyre, Malawi
| | - Thomas E. Keller
- Division of Infectious Disease and International Medicine, Department of Internal Medicine, University of South Florida, Tampa, Florida, USA
| | - Stephen T.J. Ray
- Malawi-Liverpool Wellcome Trust Clinical Research Programme, Blantyre, Malawi
- Blantyre Malaria Project, Kamuzu University of Health Sciences, Blantyre, Malawi
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford, Oxford, United Kingdom
- Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Terrie E. Taylor
- Blantyre Malaria Project, Kamuzu University of Health Sciences, Blantyre, Malawi
- Department of Osteopathic Medical Specialties, Michigan State University, East Lansing, Michigan, USA
| | - Stephen J. Rogerson
- Department of Medicine (RMH), and
- Department of Infectious Diseases, Doherty Institute, The University of Melbourne, Melbourne, Australia
| | - Wilson L. Mandala
- Malawi-Liverpool Wellcome Trust Clinical Research Programme, Blantyre, Malawi
- Biomedical Department, University of Malawi College of Medicine, Blantyre, Malawi
- Academy of Medical Sciences, Malawi University of Science and Technology, Thyolo, Malawi
| | - Morayma Reyes Gil
- Department of Pathology, Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, New York, USA
| | - Karl B. Seydel
- Blantyre Malaria Project, Kamuzu University of Health Sciences, Blantyre, Malawi
- Department of Osteopathic Medical Specialties, Michigan State University, East Lansing, Michigan, USA
| | - Kami Kim
- Division of Infectious Disease and International Medicine, Department of Internal Medicine, University of South Florida, Tampa, Florida, USA
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Figueroa-Romero A, Saura-Lázaro A, Fernández-Luis S, González R. Uncovering HIV and malaria interactions: the latest evidence and knowledge gaps. Lancet HIV 2024:S2352-3018(24)00035-3. [PMID: 38458223 DOI: 10.1016/s2352-3018(24)00035-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Revised: 02/12/2024] [Accepted: 02/12/2024] [Indexed: 03/10/2024]
Abstract
The geographical distribution of malaria and HIV infections widely overlap in sub-Saharan Africa, constituting a complex global health challenge. The interplay between both infections raises concerns about potential immunological, clinical, and therapeutic interactions. Both diseases have been reported to exacerbate the transmission of the other, including the possible vertical transmission of HIV in pregnant individuals with malaria. Co-infection also increases the risk of adverse outcomes such as severe malaria and death. In addition, interactions between antiretroviral and antimalarial drugs have been reported, potentially reducing the efficacy of these drugs. We review the current knowledge of the epidemiological, clinical, immunological, and therapeutic interactions of both infections. We focus on the latest available data and identify key knowledge gaps that should be addressed to guide policy makers in providing optimal HIV and malaria prevention, care, and treatment in vulnerable populations.
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Affiliation(s)
- Antía Figueroa-Romero
- Barcelona Institute for Global Health (ISGlobal), Hospital Clínic-Universitat de Barcelona, Barcelona, Spain; Consorcio de Investigación Biomédica en Red de Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
| | - Anna Saura-Lázaro
- Barcelona Institute for Global Health (ISGlobal), Hospital Clínic-Universitat de Barcelona, Barcelona, Spain
| | - Sheila Fernández-Luis
- Barcelona Institute for Global Health (ISGlobal), Hospital Clínic-Universitat de Barcelona, Barcelona, Spain; Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique; Pediatrics Department, Pediatric Research and Clinical Trials Unit (UPIC), Fundación para la Investigación Biomédica del Hospital 12 de Octubre, Instituto de Investigación Sanitaria Hospital 12 de Octubre (IMAS12), Madrid, Spain
| | - Raquel González
- Barcelona Institute for Global Health (ISGlobal), Hospital Clínic-Universitat de Barcelona, Barcelona, Spain; Consorcio de Investigación Biomédica en Red de Epidemiología y Salud Pública (CIBERESP), Madrid, Spain; Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique.
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4
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Wassmer SC, de Koning-Ward TF, Grau GER, Pai S. Unravelling mysteries at the perivascular space: a new rationale for cerebral malaria pathogenesis. Trends Parasitol 2024; 40:28-44. [PMID: 38065791 PMCID: PMC11072469 DOI: 10.1016/j.pt.2023.11.005] [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: 10/05/2023] [Revised: 11/13/2023] [Accepted: 11/13/2023] [Indexed: 01/06/2024]
Abstract
Cerebral malaria (CM) is a severe neurological complication caused by Plasmodium falciparum parasites; it is characterized by the sequestration of infected red blood cells within the cerebral microvasculature. New findings, combined with a better understanding of the central nervous system (CNS) barriers, have provided greater insight into the players and events involved in CM, including site-specific T cell responses in the human brain. Here, we review the updated roles of innate and adaptive immune responses in CM, with a focus on the role of the perivascular macrophage-endothelium unit in antigen presentation, in the vascular and perivascular compartments. We suggest that these events may be pivotal in the development of CM.
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Affiliation(s)
- Samuel C Wassmer
- Department of Infection Biology, London School of Hygiene & Tropical Medicine, London, UK.
| | - Tania F de Koning-Ward
- School of Medicine, Deakin University, Waurn Ponds, Victoria, Australia; Institute of Mental and Physical Health and Clinical Translation, Deakin University, Geelong, Victoria, Australia
| | - Georges E R Grau
- Vascular Immunology Unit, Discipline of Pathology, School of Medical Sciences, University of Sydney, Camperdown, New South Wales, Australia
| | - Saparna Pai
- Centre for Molecular Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, Queensland, Australia.
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5
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Howard C, Joof F, Hu R, Smith JD, Zheng Y. Probing cerebral malaria inflammation in 3D human brain microvessels. Cell Rep 2023; 42:113253. [PMID: 37819760 DOI: 10.1016/j.celrep.2023.113253] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 09/08/2023] [Accepted: 09/08/2023] [Indexed: 10/13/2023] Open
Abstract
Sequestration of Plasmodium falciparum-infected erythrocytes (IEs) in the brain microcirculation is a hallmark of cerebral malaria (CM), which leads to endothelial activation, brain swelling, and death. Here, we probed CM inflammation in a perfusable 3D human brain microvessel model. 3D brain microvessels supported in vivo-like capacities for parasite binding and maturation in situ, leading to a distinct inflammatory response from the pro-inflammatory cytokine tumor necrosis factor α (TNF-α). By combining transcriptional analysis, imaging, and leukocyte perfusion, we showed that whereas TNF-α promotes a reversible inflammatory phenotype with widespread leukocyte recruitment, parasites induce unique stress response pathways and cause localized cell adhesivity changes, focal endothelial disruptions, and apoptosis. Furthermore, parasites modified the temporal kinetics of the TNF transcriptional response, suggesting augmented inflammatory damage with the two sequential stimuli. Our findings offer mechanistic insights into CM biology in a 3D brain microvessel mimetic platform and suggest that multiple events intersect to promote brain barrier inflammation in CM.
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Affiliation(s)
- Caitlin Howard
- Department of Bioengineering, University of Washington, Seattle, WA, USA; Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA 98109, USA
| | - Fatou Joof
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA 98109, USA
| | - Ruoqian Hu
- Department of Bioengineering, University of Washington, Seattle, WA, USA; Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA 98109, USA
| | - Joseph D Smith
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA 98109, USA; Department of Pediatrics, School of Medicine, University of Washington, Seattle, WA, USA.
| | - Ying Zheng
- Department of Bioengineering, University of Washington, Seattle, WA, USA; Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA 98109, USA.
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6
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Marin AA, Juillard A, Katzin AM, Carvalho LJ, Grau GE. Perillyl alcohol modulates activation, permeability and integrity of human brain endothelial cells induced by Plasmodium falciparum. Mem Inst Oswaldo Cruz 2023; 118:e230033. [PMID: 37403869 DOI: 10.1590/0074-02760230033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Accepted: 05/26/2023] [Indexed: 07/06/2023] Open
Abstract
BACKGROUND Cerebral malaria (CM) is a severe immunovasculopathy caused for Plasmodium falciparum infection, which is characterised by the sequestration of parasitised red blood cells (pRBCs) in brain microvessels. Previous studies have shown that some terpenes, such as perillyl alcohol (POH), exhibit a marked efficacy in preventing cerebrovascular inflammation, breakdown of the brain-blood barrier (BBB) and brain leucocyte accumulation in experimental CM models. OBJECTIVE To analyse the effects of POH on the endothelium using human brain endothelial cell (HBEC) monolayers co-cultured with pRBCs. METHODOLOGY The loss of tight junction proteins (TJPs) and features of endothelial activation, such as ICAM-1 and VCAM-1 expression were evaluated by quantitative immunofluorescence. Microvesicle (MV) release by HBEC upon stimulation by P. falciparum was evaluated by flow cytometry. Finally, the capacity of POH to revert P. falciparum-induced HBEC monolayer permeability was examined by monitoring trans-endothelial electrical resistance (TEER). FINDINGS POH significantly prevented pRBCs-induced endothelial adhesion molecule (ICAM-1, VCAM-1) upregulation and MV release by HBEC, improved their trans-endothelial resistance, and restored their distribution of TJPs such as VE-cadherin, Occludin, and JAM-A. CONCLUSIONS POH is a potent monoterpene that is efficient in preventing P. falciparum-pRBCs-induced changes in HBEC, namely their activation, increased permeability and alterations of integrity, all parameters of relevance to CM pathogenesis.
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Affiliation(s)
- Adriana A Marin
- Universidade de São Paulo, Instituto de Ciências Biomédicas, Departamento de Parasitologia, São Paulo, SP, Brasil
- University of Sydney, Department of Pathology, Vascular Immunology Unit, Sydney Medical School, New South Wales, Australia
| | - Annette Juillard
- University of Sydney, Department of Pathology, Vascular Immunology Unit, Sydney Medical School, New South Wales, Australia
| | - Alejandro M Katzin
- Universidade de São Paulo, Instituto de Ciências Biomédicas, Departamento de Parasitologia, São Paulo, SP, Brasil
| | - Leonardo Jm Carvalho
- Fundação Oswaldo Cruz-Fiocruz, Instituto Oswaldo Cruz, Laboratório de Pesquisa em Malária, Rio de Janeiro, RJ, Brasil
| | - Georges Er Grau
- University of Sydney, Department of Pathology, Vascular Immunology Unit, Sydney Medical School, New South Wales, Australia
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Cimperman CK, Pena M, Gokcek SM, Theall BP, Patel MV, Sharma A, Qi C, Sturdevant D, Miller LH, Collins PL, Pierce SK, Akkaya M. Cerebral Malaria Is Regulated by Host-Mediated Changes in Plasmodium Gene Expression. mBio 2023; 14:e0339122. [PMID: 36852995 PMCID: PMC10127683 DOI: 10.1128/mbio.03391-22] [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: 02/02/2023] [Accepted: 02/06/2023] [Indexed: 03/01/2023] Open
Abstract
Cerebral malaria (CM), the deadliest complication of Plasmodium infection, is a complex and unpredictable disease. However, our understanding of the host and parasite factors that cause CM is limited. Using a mouse model of CM, experimental CM (ECM), we performed a three-way comparison between ECM-susceptible C57BL/6 mice infected with ECM-causing Plasmodium ANKA parasites [ANKA(C57BL/6)], ECM-resistant BALB/c mice infected with Plasmodium ANKA [ANKA(BALB/c)], and C57BL/6 mice infected with Plasmodium NK65 that does not cause ECM [NK65(C57BL/6)]. All ANKA(C57BL/6) mice developed CM. In contrast, in ANKA(BALB/c) and NK65(C57BL/6), infections do not result in CM and proceed similarly in terms of parasite growth, disease course, and host immune response. However, parasite gene expression in ANKA(BALB/c) was remarkably different than that in ANKA(C57BL/6) but similar to the gene expression in NK65(C57BL/6). Thus, Plasmodium ANKA has an ECM-specific gene expression profile that is activated only in susceptible hosts, providing evidence that the host has a critical influence on the outcome of infection. IMPORTANCE Hundreds of thousands of lives are lost each year due to the brain damage caused by malaria disease. The overwhelming majority of these deaths occur in young children living in sub-Saharan Africa. Thus far, there are no vaccines against this deadly disease, and we still do not know why fatal brain damage occurs in some children while others have milder, self-limiting disease progression. Our research provides an important clue to this problem. Here, we showed that the genetic background of the host has an important role in determining the course and the outcome of the disease. Our research also identified parasite molecules that can potentially be targeted in vaccination and therapy approaches.
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Affiliation(s)
- Clare K. Cimperman
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, Rockville, Maryland, USA
| | - Mirna Pena
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, Rockville, Maryland, USA
| | - Sohret M. Gokcek
- Division of Rheumatology and Immunology, Department of Internal Medicine, The Ohio State University College of Medicine, Columbus, Ohio, USA
- Department of Microbial Infection and Immunity, The Ohio State University College of Medicine, Columbus, Ohio, USA
- Pelotonia Institute for Immuno-Oncology, The James Comprehensive Cancer Center, College of Medicine, The Ohio State University, Columbus, Ohio, USA
| | - Brandon P. Theall
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, Rockville, Maryland, USA
| | - Meha V. Patel
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, Rockville, Maryland, USA
| | - Anisha Sharma
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, Rockville, Maryland, USA
| | - ChenFeng Qi
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, Rockville, Maryland, USA
| | - Daniel Sturdevant
- Research Technologies Branch, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, Hamilton, Montana, USA
| | - Louis H. Miller
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, Rockville, Maryland, USA
| | - Patrick L. Collins
- Department of Microbial Infection and Immunity, The Ohio State University College of Medicine, Columbus, Ohio, USA
- Pelotonia Institute for Immuno-Oncology, The James Comprehensive Cancer Center, College of Medicine, The Ohio State University, Columbus, Ohio, USA
| | - Susan K. Pierce
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, Rockville, Maryland, USA
| | - Munir Akkaya
- Division of Rheumatology and Immunology, Department of Internal Medicine, The Ohio State University College of Medicine, Columbus, Ohio, USA
- Department of Microbial Infection and Immunity, The Ohio State University College of Medicine, Columbus, Ohio, USA
- Pelotonia Institute for Immuno-Oncology, The James Comprehensive Cancer Center, College of Medicine, The Ohio State University, Columbus, Ohio, USA
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8
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Royo J, Vianou B, Accrombessi M, Kinkpé E, Ayédadjou L, Dossou-Dagba I, Ladipo Y, Alao MJ, Bertin GI, Cot M, Boumédiène F, Houzé S, Faucher JF, Aubouy A. Elevated plasma interleukin-8 as a risk factor for mortality in children presenting with cerebral malaria. Infect Dis Poverty 2023; 12:8. [PMID: 36759905 PMCID: PMC9909955 DOI: 10.1186/s40249-023-01059-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Accepted: 01/26/2023] [Indexed: 02/11/2023] Open
Abstract
BACKGROUND Cerebral malaria (CM) is a neuropathology which remains one of the deadliest forms of malaria among African children. The kinetics of the pathophysiological mechanisms leading to neuroinflammation and the death or survival of patients during CM are still poorly understood. The increasing production of cytokines, chemokines and other actors of the inflammatory and oxidative response by various local actors in response to neuroinflammation plays a major role during CM, participating in both the amplification of the neuroinflammation phenomenon and its resolution. In this study, we aimed to identify risk factors for CM death among specific variables of inflammatory and oxidative responses to improve our understanding of CM pathogenesis. METHODS Children presenting with CM (n = 70) due to P. falciparum infection were included in southern Benin and divided according to the clinical outcome into 50 children who survived and 20 who died. Clinical examination was complemented by fundoscopic examination and extensive blood biochemical analysis associated with molecular diagnosis by multiplex PCR targeting 14 pathogens in the patients' cerebrospinal fluid to rule out coinfections. Luminex technology and enzyme immunoassay kits were used to measure 17 plasma and 7 urinary biomarker levels, respectively. Data were analysed by univariate analysis using the nonparametric Mann‒Whitney U test and Pearson's Chi2 test. Adjusted and multivariate analyses were conducted separately for plasma and urinary biomarkers to identify CM mortality risk factors. RESULTS Univariate analysis revealed higher plasma levels of tumour necrosis factor (TNF), interleukin-1beta (IL-1β), IL-10, IL-8, C-X-C motif chemokine ligand 9 (CXCL9), granzyme B, and angiopoietin-2 and lower urinary levels of prostanglandine E2 metabolite (PGEM) in children who died compared to those who survived CM (Mann-Whitney U-test, P-values between 0.03 and < 0.0001). The multivariate logistic analysis highlighted elevated plasma levels of IL-8 as the main risk factor for death during CM (adjusted odd ratio = 14.2, P-value = 0.002). Values obtained during follow-up at D3 and D30 revealed immune factors associated with disease resolution, including plasma CXCL5, C-C motif chemokine ligand 17 (CCL17), CCL22, and urinary 15-F2t-isoprostane. CONCLUSIONS The main risk factor of death during CM was thus elevated plasma levels of IL-8 at inclusion. Follow-up of patients until D30 revealed marker profiles of disease aggravation and resolution for markers implicated in neutrophil activation, endothelium activation and damage, inflammatory and oxidative response. These results provide important insight into our understanding of CM pathogenesis and clinical outcome and may have important therapeutic implications.
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Affiliation(s)
- Jade Royo
- grid.508721.9UMR152 PHARMADEV, IRD, UPS, Toulouse University, 35 Chemin Des Maraichers, 31400 Toulouse, France
| | - Bertin Vianou
- grid.508721.9UMR152 PHARMADEV, IRD, UPS, Toulouse University, 35 Chemin Des Maraichers, 31400 Toulouse, France ,Clinical Research Institute of Benin (IRCB), Abomey Calavi, Benin
| | - Manfred Accrombessi
- Clinical Research Institute of Benin (IRCB), Abomey Calavi, Benin ,grid.8991.90000 0004 0425 469XFaculty of Infectious and Tropical Diseases, Disease Control Department, London School of Hygiene and Tropical Medicine, London, UK
| | - Elisée Kinkpé
- Paediatric Department, Calavi Hospital, Calavi, Benin
| | - Linda Ayédadjou
- Paediatric Department, Mother and Child University and Hospital Center (CHU-MEL), Cotonou, Benin
| | | | - Yélé Ladipo
- Paediatric Department, Mother and Child University and Hospital Center (CHU-MEL), Cotonou, Benin
| | - Maroufou Jules Alao
- Paediatric Department, Mother and Child University and Hospital Center (CHU-MEL), Cotonou, Benin
| | | | - Michel Cot
- grid.462420.6UMR261 MERIT, IRD, Paris University, Paris, France
| | - Farid Boumédiène
- grid.9966.00000 0001 2165 4861UMR 1094 EpiMaCT, Inserm, Limoges University Hospital, Limoges University, Limoges, France
| | - Sandrine Houzé
- grid.462420.6UMR261 MERIT, IRD, Paris University, Paris, France ,grid.411119.d0000 0000 8588 831XFrench Malaria Reference Center, APHP, Bichat Hospital, Paris, France ,grid.411119.d0000 0000 8588 831XParasitology Laboratory, APHP, Bichat-Claude-Bernard Hospital, Paris, France
| | - Jean François Faucher
- grid.9966.00000 0001 2165 4861UMR 1094 EpiMaCT, Inserm, Limoges University Hospital, Limoges University, Limoges, France ,grid.411178.a0000 0001 1486 4131Infectious Diseases and Tropical Medicine Department, Limoges University Hospital, Limoges, France
| | - Agnès Aubouy
- UMR152 PHARMADEV, IRD, UPS, Toulouse University, 35 Chemin Des Maraichers, 31400, Toulouse, France. .,Clinical Research Institute of Benin (IRCB), Abomey Calavi, Benin.
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Nortey LN, Anning AS, Nakotey GK, Ussif AM, Opoku YK, Osei SA, Aboagye B, Ghartey-Kwansah G. Genetics of cerebral malaria: pathogenesis, biomarkers and emerging therapeutic interventions. Cell Biosci 2022; 12:91. [PMID: 35715862 PMCID: PMC9204375 DOI: 10.1186/s13578-022-00830-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Accepted: 06/07/2022] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Cerebral malaria (CM) is a preeminent cause of severe disease and premature deaths in Sub-Saharan Africa, where an estimated 90% of cases occur. The key features of CM are a deep, unarousable coma that persists for longer than 1 h in patients with peripheral Plasmodium falciparum and no other explanation for encephalopathy. Significant research efforts on CM in the last few decades have focused on unravelling the molecular underpinnings of the disease pathogenesis and the identification of potential targets for therapeutic or pharmacologic intervention. These efforts have been greatly aided by the generation and study of mouse models of CM, which have provided great insights into key events of CM pathogenesis, revealed an interesting interplay of host versus parasite factors that determine the progression of malaria to severe disease and exposed possible targets for therapeutic intervention in severe disease.
Main Body
This paper reviews our current understanding of the pathogenic and immunologic factors involved in CM. We present the current view of the roles of certain gene products e.g., the var gene, ABCA-1, ICAM-1, TNF-alpha, CD-36, PfEMP-1 and G6PD, in CM pathogenesis. We also present alterations in the blood–brain barrier as a consequence of disease proliferation as well as complicated host and parasite interactions, including the T-cell immune reaction, reduced deformation of erythrocytes and cytoadherence. We further looked at recent advances in cerebral malaria treatment interventions by emphasizing on biomarkers, new diagnostic tools and emerging therapeutic options.
Conclusion
Finally, we discuss how the current understanding of some of these pathogenic and immunologic factors could inform the development of novel therapeutic interventions to fight CM.
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10
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Mirzohreh ST, Safarpour H, Pagheh AS, Bangoura B, Barac A, Ahmadpour E. Malaria prevalence in HIV-positive children, pregnant women, and adults: a systematic review and meta-analysis. PARASITES & VECTORS 2022; 15:324. [PMID: 36104731 PMCID: PMC9472338 DOI: 10.1186/s13071-022-05432-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Accepted: 08/15/2022] [Indexed: 11/10/2022]
Abstract
Abstract
Background
Malaria in human immunodeficiency virus (HIV)-positive patients is an ever-increasing global burden for human health. The present meta-analysis summarizes published literature on the prevalence of malaria infection in HIV-positive children, pregnant women and adults.
Methods
This study followed the PRISMA guideline. The PubMed, Science Direct, Google Scholar, Scopus and Cochrane databases were searched for relevant entries published between 1 January 1983 and 1 March 2020. All peer-reviewed original papers evaluating the prevalence of malaria among HIV-positive patients were included. Incoherence and heterogeneity between studies were quantified by the I2 index and Cochran’s Q test. Publication and population biases were assessed with funnel plots, and Egger’s regression asymmetry test.
Results
A total of 106 studies were included in this systematic review. The average prevalence of malaria among HIV-positive children, HIV-positive pregnant women and HIV-positive adults was 39.4% (95% confidence interval [CI]: 26.6–52.9), 32.3% (95% CI = 26.3–38.6) and 27.3% (95% CI = 20.1–35.1), respectively. In adult patients with HIV, CD4+ (cluster of differentiation 4) < 200 cells/µl and age < 40 years were associated with a significant increase in the odds of malaria infection (odds ratio [OR] = 1.5, 95% CI = 1.2–1.7 and OR = 1.1, 95% CI = 1–1.3, respectively). Antiretroviral therapy (ART) and being male were associated with a significant decrease in the chance of malaria infection in HIV-positive adults (OR = 0.8, 95% CI = 0.7–0.9 and OR = 0.2, 95% CI = 0.2–0.3, respectively). In pregnant women with HIV, CD4+ count < 200 cells/µl was related to a higher risk for malaria infection (OR = 1.5, 95% CI = 1.1–1.9).
Conclusions
This systematic review demonstrates that malaria infection is concerningly common among HIV-positive children, pregnant women and adults. Among HIV-positive adults, ART medication and being male were associated with a substantial decrease in infection with malaria. For pregnant women, CD4+ count of < 200 cells/µl was a considerable risk factor for malaria infection.
Graphical Abstract
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11
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An update on cerebral malaria for therapeutic intervention. Mol Biol Rep 2022; 49:10579-10591. [PMID: 35670928 DOI: 10.1007/s11033-022-07625-5] [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: 12/01/2021] [Accepted: 05/20/2022] [Indexed: 10/18/2022]
Abstract
BACKGROUND Cerebral malaria is often pronounced as a major life-threatening neurological complication of Plasmodium falciparum infection. The complex pathogenic landscape of the parasite and the associated neurological complications are still not elucidated properly. The growing concerns of drugresistant parasite strains along with the failure of anti-malarial drugs to subdue post-recovery neuro-cognitive dysfunctions in cerebral malaria patients have called for a demand to explore novel biomarkers and therapeutic avenues. Due course of the brain infection journey of the parasite, events such as sequestration of infected RBCs, cytoadherence, inflammation, endothelial activation, and blood-brain barrier disruption are considered critical. METHODS In this review, we briefly summarize the diverse pathogenesis of the brain-invading parasite associated with loss of the blood-brain barrier integrity. In addition, we also discuss proteomics, transcriptomics, and bioinformatics strategies to identify an array of new biomarkers and drug candidates. CONCLUSION A proper understanding of the parasite biology and mechanism of barrier disruption coupled with emerging state-of-art therapeutic approaches could be helpful to tackle cerebral malaria.
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12
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Borgstein A, Zhang B, Lam C, Gushu MB, Liomba AW, Malenga A, Pensulo P, Tebulo A, Small DS, Taylor T, Seydel K. Delayed presentation to hospital care is associated with sequelae but not mortality in children with cerebral malaria in Malawi. Malar J 2022; 21:60. [PMID: 35193585 PMCID: PMC8864854 DOI: 10.1186/s12936-022-04080-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2021] [Accepted: 02/06/2022] [Indexed: 11/10/2022] Open
Abstract
Background Cerebral malaria is still a major cause of death in children in sub-Saharan Africa. Among survivors, debilitating neurological sequelae can leave children with permanent cognitive impairments and societal stigma, resulting in taxing repercussions for their families. This study investigated the effect of delay in presentation to medical care on outcome in children with cerebral malaria in Malawi. Methods This retrospective study included participants enrolled in a longstanding study of cerebral malaria between 2001 and 2021 and considered coma duration prior to arrival at hospital (with or without anti-malarial treatment), HIV status, blood lactate levels at admission and age as factors that could affect clinical outcome. Outcomes were categorized as full recovery, sequelae at the time of discharge, or death. A multinomial regression was fit and run controlling for coma duration, HIV status, lactate levels and age, to determine the association between each explanatory variable and outcome. Results A total of 1663 children with cerebral malaria, aged 6 months to 14 years were included. Longer coma duration (in hours) was associated with greater odds of developing sequelae (OR = 1.023, 95% CI 1.007–1.039, p = 0.006) but not death (OR = 1.00, 95% CI 0.986–1.015, p = 0.961). Younger age (in months) was also correlated with higher rates of sequelae, (OR = 0.990, 95% CI 0.983–0.997, p = 0.004) but not with increased mortality (OR = 0.998, 95% CI 0.993–1.003, p = 0.335). Blood lactate levels on admission were correlated with mortality (OR = 1.125, 95% CI 1.090–1.161, p < 0.001) but not associated with increased rates of sequelae (OR = 1.016, 95% CI 0.973–1.060, p = 0.475). Positive HIV status and treatment with an anti-malarial (artemisinin or non-artemisinin-based) prior to arrival at the hospital were not significantly associated with either adverse outcome. Conclusions In Malawian children with cerebral malaria, higher rates of sequelae were significantly associated with extended coma duration prior to admission and younger age. Mortality rates were correlated with increased lactate levels on admission. The differential effects of variables on clinical outcomes suggest that there may be different pathogenic pathways leading to sequelae and death. Actions taken by parents and health care professionals are critical in defining when patients arrive at hospital and determining their ultimate outcome. Supplementary Information The online version contains supplementary material available at 10.1186/s12936-022-04080-2.
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Affiliation(s)
- Arabella Borgstein
- Blantyre Malaria Project, Kamuzu University of Health Sciences, Private Bag 360, Blantyre, Malawi.,St. George's University of London/University of Nicosia Medical School, Nicosia, Cyprus
| | - Bo Zhang
- Department of Statistics and Data Science, The Wharton School, University of Pennsylvania, Philadelphia, USA
| | - Colin Lam
- Bronx High School of Science, Bronx, NY, USA
| | - Montfort Bernard Gushu
- Blantyre Malaria Project, Kamuzu University of Health Sciences, Private Bag 360, Blantyre, Malawi
| | - Alice Wangui Liomba
- Blantyre Malaria Project, Kamuzu University of Health Sciences, Private Bag 360, Blantyre, Malawi
| | - Albert Malenga
- Blantyre Malaria Project, Kamuzu University of Health Sciences, Private Bag 360, Blantyre, Malawi
| | - Paul Pensulo
- Blantyre Malaria Project, Kamuzu University of Health Sciences, Private Bag 360, Blantyre, Malawi
| | - Andrew Tebulo
- Blantyre Malaria Project, Kamuzu University of Health Sciences, Private Bag 360, Blantyre, Malawi
| | - Dylan S Small
- Department of Statistics and Data Science, The Wharton School, University of Pennsylvania, Philadelphia, USA
| | - Terrie Taylor
- Blantyre Malaria Project, Kamuzu University of Health Sciences, Private Bag 360, Blantyre, Malawi.,Department of Osteopathic Medical Specialties, College of Osteopathic Medicine, Michigan State University, East Lansing, MI, USA
| | - Karl Seydel
- Blantyre Malaria Project, Kamuzu University of Health Sciences, Private Bag 360, Blantyre, Malawi. .,Department of Osteopathic Medical Specialties, College of Osteopathic Medicine, Michigan State University, East Lansing, MI, USA. .,Malawi-Liverpool-Wellcome Trust Research Programme, Kamuzu University of Health Sciences, Blantyre, Malawi.
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13
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Simwela NV, Waters AP. Current status of experimental models for the study of malaria. Parasitology 2022; 149:1-22. [PMID: 35357277 PMCID: PMC9378029 DOI: 10.1017/s0031182021002134] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Revised: 12/07/2021] [Accepted: 12/08/2021] [Indexed: 01/09/2023]
Abstract
Infection by malaria parasites (Plasmodium spp.) remains one of the leading causes of morbidity and mortality, especially in tropical regions of the world. Despite the availability of malaria control tools such as integrated vector management and effective therapeutics, these measures have been continuously undermined by the emergence of vector resistance to insecticides or parasite resistance to frontline antimalarial drugs. Whilst the recent pilot implementation of the RTS,S malaria vaccine is indeed a remarkable feat, highly effective vaccines against malaria remain elusive. The barriers to effective vaccines result from the complexity of both the malaria parasite lifecycle and the parasite as an organism itself with consequent major gaps in our understanding of their biology. Historically and due to the practical and ethical difficulties of working with human malaria infections, research into malaria parasite biology has been extensively facilitated by animal models. Animals have been used to study disease pathogenesis, host immune responses and their (dys)regulation and further disease processes such as transmission. Moreover, animal models remain at the forefront of pre-clinical evaluations of antimalarial drugs (drug efficacy, mode of action, mode of resistance) and vaccines. In this review, we discuss commonly used animal models of malaria, the parasite species used and their advantages and limitations which hinder their extrapolation to actual human disease. We also place into this context the most recent developments such as organoid technologies and humanized mice.
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Affiliation(s)
- Nelson V. Simwela
- Institute of Infection, Immunity & Inflammation, Wellcome Centre for Integrative Parasitology, University of Glasgow, Glasgow, UK
| | - Andrew P. Waters
- Institute of Infection, Immunity & Inflammation, Wellcome Centre for Integrative Parasitology, University of Glasgow, Glasgow, UK
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14
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Rubach MP, Mukemba JP, Florence SM, Lopansri BK, Hyland K, Simmons RA, Langelier C, Nakielny S, DeRisi JL, Yeo TW, Anstey NM, Weinberg JB, Mwaikambo ED, Granger DL. Cerebrospinal Fluid Pterins, Pterin-Dependent Neurotransmitters, and Mortality in Pediatric Cerebral Malaria. J Infect Dis 2021; 224:1432-1441. [PMID: 33617646 PMCID: PMC8682765 DOI: 10.1093/infdis/jiab086] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 02/10/2021] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Cerebral malaria (CM) pathogenesis remains incompletely understood. Having shown low systemic levels of tetrahydrobiopterin (BH4), an enzymatic cofactor for neurotransmitter synthesis, we hypothesized that BH4 and BH4-dependent neurotransmitters would likewise be low in cerebrospinal fluid (CSF) in CM. METHODS We prospectively enrolled Tanzanian children with CM and children with nonmalaria central nervous system conditions (NMCs). We measured CSF levels of BH4, neopterin, and BH4-dependent neurotransmitter metabolites, 3-O-methyldopa, homovanillic acid, and 5-hydroxyindoleacetate, and we derived age-adjusted z-scores using published reference ranges. RESULTS Cerebrospinal fluid BH4 was elevated in CM (n = 49) compared with NMC (n = 51) (z-score 0.75 vs -0.08; P < .001). Neopterin was increased in CM (z-score 4.05 vs 0.09; P < .001), and a cutoff at the upper limit of normal (60 nmol/L) was 100% sensitive for CM. Neurotransmitter metabolite levels were overall preserved. A higher CSF BH4/BH2 ratio was associated with increased odds of survival (odds ratio, 2.94; 95% confidence interval, 1.03-8.33; P = .043). CONCLUSION Despite low systemic BH4, CSF BH4 was elevated and associated with increased odds of survival in CM. Coma in malaria is not explained by deficiency of BH4-dependent neurotransmitters. Elevated CSF neopterin was 100% sensitive for CM diagnosis and warrants further assessment of its clinical utility for ruling out CM in malaria-endemic areas.
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Affiliation(s)
- Matthew P Rubach
- Department of Medicine, Division of Infectious Diseases, Duke University, Durham, North Carolina, USA
- Duke Global Health Institute, Duke University, Durham, North Carolina, USA
| | - Jackson P Mukemba
- Department of Pediatrics, Hubert Kairuki Memorial University, Dar es Salaam, United Republic of Tanzania
| | - Salvatore M Florence
- Department of Pediatrics, Hubert Kairuki Memorial University, Dar es Salaam, United Republic of Tanzania
| | - Bert K Lopansri
- Department of Medicine, Intermountain Healthcare, Salt Lake City, Utah, USA
- Department of Medicine, University of Utah School of Medicine and VA Medical Center, Salt Lake City, Utah, USA
| | - Keith Hyland
- Medical Neurogenetics Laboratories, Atlanta, Georgia, USA
| | - Ryan A Simmons
- Duke Global Health Institute, Duke University, Durham, North Carolina, USA
- Department of Biostatistics, Duke University, Durham, North Carolina, USA
| | - Charles Langelier
- Department of Medicine, Division of Infectious Diseases, University of California San Francisco, San Francisco, California, USA
- Chan Zuckerberg Biohub, San Francisco, California, USA
| | - Sara Nakielny
- Chan Zuckerberg Biohub, San Francisco, California, USA
| | - Joseph L DeRisi
- Chan Zuckerberg Biohub, San Francisco, California, USA
- Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, California, USA
| | - Tsin W Yeo
- Global and Tropical Health Division, Menzies School of Health Research, Darwin, Australia
- Division of Medicine, Royal Darwin Hospital, Darwin, Northern Territory, Australia
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore
| | - Nicholas M Anstey
- Global and Tropical Health Division, Menzies School of Health Research, Darwin, Australia
- Division of Medicine, Royal Darwin Hospital, Darwin, Northern Territory, Australia
| | - J Brice Weinberg
- Department of Medicine, Duke University and VA Medical Centers, Durham, North Carolina, USA
| | - Esther D Mwaikambo
- Department of Pediatrics, Hubert Kairuki Memorial University, Dar es Salaam, United Republic of Tanzania
| | - Donald L Granger
- Department of Medicine, University of Utah School of Medicine and VA Medical Center, Salt Lake City, Utah, USA
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15
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A meta-analysis on the prevalence and characteristics of severe malaria in patients with Plasmodium spp. and HIV co-infection. Sci Rep 2021; 11:16655. [PMID: 34404814 PMCID: PMC8371128 DOI: 10.1038/s41598-021-95591-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Accepted: 07/28/2021] [Indexed: 11/20/2022] Open
Abstract
Co-infection with malaria and human immunodeficiency virus (HIV) increases the severity and mortality rates of both diseases. A better understanding of the effects of co-infections could help in the diagnosis, prompt treatment, prevention, and control of malarial parasites among HIV-infected patients. In this systematic review and meta-analysis, we estimated the prevalence and characteristics of severe malaria (SM) caused by co-infection with HIV. We included relevant studies that were conducted between the years 1991 and 2018 and reporting on SM. We pooled the prevalence of SM in patients with co-infection, pooled odds ratios of SM in patients with co-infection and Plasmodium mono-infection, and differences in laboratory parameters such as parasite density and leucocyte counts, between co-infected and Plasmodium mono-infected patients. The meta-analysis included 29 studies (1126 SM cases). The pooled prevalence of SM in co-infected patients using the data of 23 studies (SM = 795 cases, all co-infection cases = 2534 cases) was 43.0% (95% confidence interval [CI] 31.0–56.0%; I2, 98.0%). Overall, the odds of SM from 18 studies were pooled. The odds of SM were significantly higher in co-infected patients than in Plasmodium mono-infected patients (OR 2.41; 95% CI 1.43–4.08; I2 = 85%; P = 0.001) and also significantly higher in children (OR 9.69; 95% CI 5.14–18.3; I2, 0%; P < 0.0001; two studies) than in adults (OR 2.68; 95% CI 1.52–4.73; I2, 79.0%; P = 0.0007; 12 studies). Co-infected patients with SM had a higher parasite density than those with Plasmodium mono-infection when the data of seven studies were analysed (SMD, 1.25; 95% CI 0.14–2.36; I2, 98.0%; P = 0.03) and higher leukocyte counts when the data of four studies were analysed (MD, 1570 cells/µL; 95% CI 850–2300 cells/µL; I2, 21.0%; P < 0.0001). Thus, the prevalence of SM among patients co-infected with Plasmodium spp. and HIV is high. Because co-infections could lead to SM, patients with Plasmodium spp. and HIV co-infection should be identified and treated to reduce the prevalence of SM and the number of deaths.
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16
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Perillyl alcohol reduces parasite sequestration and cerebrovascular dysfunction during experimental cerebral malaria. Antimicrob Agents Chemother 2021; 65:AAC.00004-21. [PMID: 33649109 PMCID: PMC8092904 DOI: 10.1128/aac.00004-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Cerebral malaria (CM) is a severe immunovasculopathy which presents high mortality rate (15-20%), despite the availability of artemisinin-based therapy. More effective immunomodulatory and/or antiparasitic therapies are urgently needed. Experimental Cerebral Malaria (ECM) in mice is used to elucidate aspects involved in this pathology since manifests many of the neurological features of CM. In the present study, we evaluated the potential mechanisms involved in the protection afforded by perillyl alcohol (POH) in mouse strains susceptible to CM caused by Plasmodium berghei ANKA (PbA) infection through intranasal preventive treatment. Additionally, to evaluate the interaction of POH with the cerebral endothelium using an in vitro model of human brain endothelial cells (HBEC). Pharmacokinetic approaches demonstrated constant and prolonged levels of POH in the plasma and brain after a single intranasal dose. Treatment with POH effectively prevented vascular dysfunction. Furthermore, treatment with POH reduced the endothelial cell permeability and PbA s in the brain and spleen. Finally, POH treatment decreased the accumulation of macrophages and T and B cells in the spleen and downregulated the expression of endothelial adhesion molecules (ICAM-1, VCAM-1, and CD36) in the brain. POH is a potent monoterpene that prevents cerebrovascular dysfunction in vivo and in vitro, decreases parasite sequestration, and modulates different processes related to the activation, permeability, and integrity of the blood brain barrier (BBB), thereby preventing cerebral oedema and inflammatory infiltrates.
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17
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Qin J, Lovelace MD, Mitchell AJ, de Koning-Ward T, Grau GE, Pai S. Perivascular macrophages create an intravascular niche for CD8 + T cell localisation prior to the onset of fatal experimental cerebral malaria. Clin Transl Immunology 2021; 10:e1273. [PMID: 33854773 PMCID: PMC8026342 DOI: 10.1002/cti2.1273] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 02/03/2021] [Accepted: 03/14/2021] [Indexed: 12/12/2022] Open
Abstract
Objectives The immunologic events that build up to the fatal neurological stage of experimental cerebral malaria (ECM) are incompletely understood. Here, we dissect immune cell behaviour occurring in the central nervous system (CNS) when Plasmodium berghei ANKA (PbA)‐infected mice show only minor clinical signs. Methods A 2‐photon intravital microscopy (2P‐IVM) brain imaging model was used to study the spatiotemporal context of early immunological events in situ during ECM. Results Early in the disease course, antigen‐specific CD8+ T cells came in contact and arrested on the endothelium of post‐capillary venules. CD8+ T cells typically adhered adjacent to, or were in the near vicinity of, perivascular macrophages (PVMs) that line post‐capillary venules. Closer examination revealed that CD8+ T cells crawled along the inner vessel wall towards PVMs that lay on the abluminal side of large post‐capillary venules. ‘Activity hotspots’ in large post‐capillary venules were characterised by T‐cell localisation, activated morphology and clustering of PVM, increased abutting of post‐capillary venules by PVM and augmented monocyte accumulation. In the later stages of infection, when mice exhibited neurological signs, intravascular CD8+ T cells increased in number and changed their behaviour, actively crawling along the endothelium and displaying frequent, short‐term interactions with the inner vessel wall at hotspots. Conclusion Our study suggests an active interaction between PVM and CD8+ T cells occurs across the blood–brain barrier (BBB) in early ECM, which may be the initiating event in the inflammatory cascade leading to BBB alteration and neuropathology.
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Affiliation(s)
| | - Michael D Lovelace
- Applied Neurosciences Program Peter Duncan Neurosciences Research Unit St Vincent's Centre for Applied Medical Research Sydney NSW Australia.,UNSW St Vincent's Clinical School Faculty of Medicine UNSW Sydney Sydney NSW Australia
| | - Andrew J Mitchell
- Materials Characterisation and Fabrication Platform Department of Chemical Engineering University of Melbourne Parkville VIC Australia
| | | | - Georges Er Grau
- Vascular Immunology Unit Discipline of Pathology School of Medical Sciences University of Sydney Camperdown NSW Australia
| | - Saparna Pai
- Centre for Molecular Therapeutics Australian Institute of Tropical Health and Medicine James Cook University Cairns QLD Australia.,Faculty of Medicine and Health University of Sydney Sydney NSW Australia
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18
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Bioengineered 3D Microvessels for Investigating Plasmodium falciparum Pathogenesis. Trends Parasitol 2021; 37:401-413. [PMID: 33485788 DOI: 10.1016/j.pt.2020.12.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 12/15/2020] [Accepted: 12/25/2020] [Indexed: 12/18/2022]
Abstract
Plasmodium falciparum pathogenesis is complex and intimately connected to vascular physiology. This is exemplified by cerebral malaria (CM), a neurovascular complication that accounts for most of the malaria deaths worldwide. P. falciparum sequestration in the brain microvasculature is a hallmark of CM and is not replicated in animal models. Numerous aspects of the disease are challenging to fully understand from clinical studies, such as parasite binding tropism or causal pathways in blood-brain barrier breakdown. Recent bioengineering approaches allow for the generation of 3D microvessels and organ-specific vasculature that provide precise control of vessel architecture and flow dynamics, and hold great promise for malaria research. Here, we discuss recent and future applications of bioengineered microvessels in malaria pathogenesis research.
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19
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Patel H, Dunican C, Cunnington AJ. Predictors of outcome in childhood Plasmodium falciparum malaria. Virulence 2020; 11:199-221. [PMID: 32063099 PMCID: PMC7051137 DOI: 10.1080/21505594.2020.1726570] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 01/16/2020] [Accepted: 01/20/2020] [Indexed: 12/16/2022] Open
Abstract
Plasmodium falciparum malaria is classified as either uncomplicated or severe, determining clinical management and providing a framework for understanding pathogenesis. Severe malaria in children is defined by the presence of one or more features associated with adverse outcome, but there is wide variation in the predictive value of these features. Here we review the evidence for the usefulness of these features, alone and in combination, to predict death and other adverse outcomes, and we consider the role that molecular biomarkers may play in augmenting this prediction. We also examine whether a more personalized approach to predicting outcome for specific presenting syndromes of severe malaria, particularly cerebral malaria, has the potential to be more accurate. We note a general need for better external validation in studies of outcome predictors and for the demonstration that predictors can be used to guide clinical management in a way that improves survival and long-term health.
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Affiliation(s)
- Harsita Patel
- Section of Paediatric Infectious Disease, Department of Infectious Disease, Imperial College London, London, UK
| | - Claire Dunican
- Section of Paediatric Infectious Disease, Department of Infectious Disease, Imperial College London, London, UK
| | - Aubrey J. Cunnington
- Section of Paediatric Infectious Disease, Department of Infectious Disease, Imperial College London, London, UK
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20
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Riggle BA, Manglani M, Maric D, Johnson KR, Lee MH, Neto OLA, Taylor TE, Seydel KB, Nath A, Miller LH, McGavern DB, Pierce SK. CD8+ T cells target cerebrovasculature in children with cerebral malaria. J Clin Invest 2020; 130:1128-1138. [PMID: 31821175 DOI: 10.1172/jci133474] [Citation(s) in RCA: 67] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Accepted: 12/05/2019] [Indexed: 01/06/2023] Open
Abstract
BACKGROUNDCerebral malaria (CM) accounts for nearly 400,000 deaths annually in African children. Current dogma suggests that CM results from infected RBC (iRBC) sequestration in the brain microvasculature and resulting sequelae. Therapies targeting these events have been unsuccessful; findings in experimental models suggest that CD8+ T cells drive disease pathogenesis. However, these data have largely been ignored because corroborating evidence in humans is lacking. This work fills a critical gap in our understanding of CM pathogenesis that is impeding development of therapeutics.METHODSUsing multiplex immunohistochemistry, we characterized cerebrovascular immune cells in brain sections from 34 children who died from CM or other causes. Children were grouped by clinical diagnosis (CM+ or CM-), iRBC sequestration (Seqhi, Seqlo, Seq0) and HIV status (HIV+ or HIV-).RESULTSWe identified effector CD3+CD8+ T cells engaged on the cerebrovasculature in 69% of CM+ HIV- children. The number of intravascular CD3+CD8+ T cells was influenced by CM status (CM+ > CM-, P = 0.004) and sequestration level (Seqhi > Seqlo, P = 0.010). HIV coinfection significantly increased T cell numbers (P = 0.017) and shifted cells from an intravascular (P = 0.004) to perivascular (P < 0.0001) distribution.CONCLUSIONWithin the studied cohort, CM is associated with cerebrovascular engagement of CD3+CD8+ T cells, which is exacerbated by HIV coinfection. Thus, CD3+CD8+ T cells are highly promising targets for CM adjunctive therapy, opening new avenues for the treatment of this deadly disease.FUNDINGThis research was supported by the Intramural Research Program of the National Institutes of Health.
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Affiliation(s)
- Brittany A Riggle
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases (NIAID), NIH, Rockville, Maryland, USA
| | - Monica Manglani
- Viral Immunology and Intravital Imaging Section, National Institute of Neurological Disorders and Stroke (NINDS), NIH, Bethesda, Maryland, USA.,Medical Scientist Training Program, Pennsylvania State College of Medicine, Hershey, Pennsylvania, USA
| | | | - Kory R Johnson
- Information Technology Program, Division of Intramural Research, and
| | - Myoung-Hwa Lee
- Section of Infections of the Nervous System, National Institute of Neurological Disorders and Stroke, and
| | | | - Terrie E Taylor
- Department of Osteopathic Medical Specialties, College of Osteopathic Medicine, Michigan State University, East Lansing, Michigan, USA.,Blantyre Malaria Project, University of Malawi College of Medicine, Blantyre, Malawi, Africa
| | - Karl B Seydel
- Department of Osteopathic Medical Specialties, College of Osteopathic Medicine, Michigan State University, East Lansing, Michigan, USA.,Blantyre Malaria Project, University of Malawi College of Medicine, Blantyre, Malawi, Africa
| | - Avindra Nath
- Section of Infections of the Nervous System, National Institute of Neurological Disorders and Stroke, and
| | - Louis H Miller
- Laboratory of Malaria Vector Research, National Institute of Allergy and Infectious Diseases, NIH, Rockville, Maryland, USA
| | - Dorian B McGavern
- Viral Immunology and Intravital Imaging Section, National Institute of Neurological Disorders and Stroke (NINDS), NIH, Bethesda, Maryland, USA
| | - Susan K Pierce
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases (NIAID), NIH, Rockville, Maryland, USA
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21
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Kraisin S, Martinod K, Desender L, Pareyn I, Verhenne S, Deckmyn H, Vanhoorelbeke K, Van den Steen PE, De Meyer SF. von Willebrand factor increases in experimental cerebral malaria but is not essential for late-stage pathogenesis in mice. J Thromb Haemost 2020; 18:2377-2390. [PMID: 32485089 DOI: 10.1111/jth.14932] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 04/24/2020] [Accepted: 05/19/2020] [Indexed: 01/07/2023]
Abstract
BACKGROUND Cerebral malaria (CM) is the most severe complication of malaria. Endothelial activation, cytokine release, and vascular obstruction are essential hallmarks of CM. Clinical studies have suggested a link between von Willebrand factor (VWF) and malaria pathology. OBJECTIVES To investigate the contribution of VWF in the pathogenesis of experimental cerebral malaria (ECM). METHODS Both Vwf+/+ and Vwf-/- mice were infected with Plasmodium berghei ANKA (PbANKA) to induce ECM. Alterations of plasma VWF and ADAMTS13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13), platelet count, neurological features, and accumulation of platelets and leukocytes in the brain were examined following infection. RESULTS Plasma VWF levels significantly increased upon PbANKA infection in Vwf+/+ animals. While ADAMTS13 activity was not affected, high molecular weight VWF multimers disappeared at the end-stage ECM, possibly due to an ongoing hypercoagulability. Although the number of reticulocytes, a preferential target for the parasites, was increased in Vwf-/- mice compared to Vwf+/+ mice early after infection, parasitemia levels did not markedly differ between the two groups. Interestingly, Vwf-/- mice manifested overall clinical ECM features similar to those observed in Vwf+/+ animals. At day 8.5 post-infection, however, clinical ECM features in Vwf-/- mice were slightly more beneficial than in Vwf+/+ animals. Despite these minor differences, overall survival was not different between Vwf-/- and Vwf+/+ mice. Similarly, PbANKA-induced thrombocytopenia, leukocyte, and platelet accumulations in the brain were not altered by the absence of VWF. CONCLUSIONS Our study suggests that increased VWF concentration is a hallmark of ECM. However, VWF does not have a major influence in modulating late-stage ECM pathogenesis.
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Affiliation(s)
- Sirima Kraisin
- Laboratory for Thrombosis Research, KU Leuven Campus Kulak Kortrijk, Kortrijk, Belgium
| | - Kimberly Martinod
- Laboratory for Thrombosis Research, KU Leuven Campus Kulak Kortrijk, Kortrijk, Belgium
- Center for Molecular and Vascular Biology, Department of Cardiovascular Sciences, KU Leuven, Leuven, Belgium
| | - Linda Desender
- Laboratory for Thrombosis Research, KU Leuven Campus Kulak Kortrijk, Kortrijk, Belgium
| | - Inge Pareyn
- Laboratory for Thrombosis Research, KU Leuven Campus Kulak Kortrijk, Kortrijk, Belgium
| | - Sebastien Verhenne
- Laboratory for Thrombosis Research, KU Leuven Campus Kulak Kortrijk, Kortrijk, Belgium
| | - Hans Deckmyn
- Laboratory for Thrombosis Research, KU Leuven Campus Kulak Kortrijk, Kortrijk, Belgium
| | - Karen Vanhoorelbeke
- Laboratory for Thrombosis Research, KU Leuven Campus Kulak Kortrijk, Kortrijk, Belgium
| | - Philippe E Van den Steen
- Laboratory of Immunoparasitology, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
| | - Simon F De Meyer
- Laboratory for Thrombosis Research, KU Leuven Campus Kulak Kortrijk, Kortrijk, Belgium
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22
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MacCormick IJC, Barrera V, Beare NAV, Czanner G, Potchen M, Kampondeni S, Heyderman RS, Craig AG, Molyneux ME, Mallewa M, White VA, Milner D, Hiscott P, Taylor TE, Seydel KB, Harding SP. How Does Blood-Retinal Barrier Breakdown Relate to Death and Disability in Pediatric Cerebral Malaria? J Infect Dis 2020; 225:1070-1080. [PMID: 32845969 PMCID: PMC8922008 DOI: 10.1093/infdis/jiaa541] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 08/24/2020] [Indexed: 11/25/2022] Open
Abstract
Background In cerebral malaria, the retina can be used to understand disease pathogenesis. The mechanisms linking sequestration, brain swelling, and death remain poorly understood. We hypothesized that retinal vascular leakage would be associated with brain swelling. Methods We used retinal angiography to study blood-retinal barrier integrity. We analyzed retinal leakage, histopathology, brain magnatic resonance imaging (MRI), and associations with death and neurological disability in prospective cohorts of Malawian children with cerebral malaria. Results Three types of retinal leakage were seen: large focal leak (LFL), punctate leak (PL), and vessel leak. The LFL and PL were associated with death (odds ratio [OR] = 13.20, 95% confidence interval [CI] = 5.21–33.78 and OR = 8.58, 95% CI = 2.56–29.08, respectively) and brain swelling (P < .05). Vessel leak and macular nonperfusion were associated with neurological disability (OR = 3.71, 95% CI = 1.26–11.02 and OR = 9.06, 95% CI = 1.79–45.90). Large focal leak was observed as an evolving retinal hemorrhage. A core of fibrinogen and monocytes was found in 39 (93%) white-centered hemorrhages. Conclusions Blood-retina barrier breakdown occurs in 3 patterns in cerebral malaria. Associations between LFL, brain swelling, and death suggest that the rapid accumulation of cerebral hemorrhages, with accompanying fluid egress, may cause fatal brain swelling. Vessel leak, from barrier dysfunction, and nonperfusion were not associated with severe brain swelling but with neurological deficits, suggesting hypoxic injury in survivors.
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Affiliation(s)
- Ian J C MacCormick
- Department of Eye and Vision Science, Institute of Life Course and Medical Sciences, University of Liverpool, a member of Liverpool Health Partners, Liverpool, UK.,Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Queen Elizabeth Central Hospital, Blantyre, Malawi.,Centre for Inflammation Research, University of Edinburgh, Edinburgh, UK
| | - Valentina Barrera
- Department of Eye and Vision Science, Institute of Life Course and Medical Sciences, University of Liverpool, a member of Liverpool Health Partners, Liverpool, UK.,NHS Blood and Transplant, Tissue and Eye Services R&D, Liverpool UK
| | - Nicholas A V Beare
- Department of Eye and Vision Science, Institute of Life Course and Medical Sciences, University of Liverpool, a member of Liverpool Health Partners, Liverpool, UK.,St. Paul's Eye Unit, Liverpool University Hospitals Foundation Trust, Liverpool, UK
| | - Gabriela Czanner
- Department of Eye and Vision Science, Institute of Life Course and Medical Sciences, University of Liverpool, a member of Liverpool Health Partners, Liverpool, UK.,Department of Applied Mathematics, Liverpool John Moores University, Liverpool, UK
| | - Michael Potchen
- Department of Imaging Sciences, University of Rochester Medical Center, Rochester, NY, USA
| | - Samuel Kampondeni
- Department of Imaging Sciences, University of Rochester Medical Center, Rochester, NY, USA.,Blantyre Malaria Project, University of Malawi College of Medicine, Blantyre, Malawi
| | - Robert S Heyderman
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Queen Elizabeth Central Hospital, Blantyre, Malawi.,Division of Infection & Immunity, University College London, London, UK
| | - Alister G Craig
- Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, UK
| | - Malcolm E Molyneux
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Queen Elizabeth Central Hospital, Blantyre, Malawi.,Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, UK
| | - Macpherson Mallewa
- Department of Paediatrics and Child Health, Queen Elizabeth Central Hospital, Blantyre, Malawi
| | - Valerie A White
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Dan Milner
- American Society for Clinical Pathology, Chicago, IL, USA
| | - Paul Hiscott
- Department of Eye and Vision Science, Institute of Life Course and Medical Sciences, University of Liverpool, a member of Liverpool Health Partners, Liverpool, UK
| | - Terrie E Taylor
- Blantyre Malaria Project, University of Malawi College of Medicine, Blantyre, Malawi.,Department of Osteopathic Medical Specialties, College of Osteopathic Medicine, Michigan State University, East Lansing, USA
| | - Karl B Seydel
- Blantyre Malaria Project, University of Malawi College of Medicine, Blantyre, Malawi.,Department of Osteopathic Medical Specialties, College of Osteopathic Medicine, Michigan State University, East Lansing, USA
| | - Simon P Harding
- Department of Eye and Vision Science, Institute of Life Course and Medical Sciences, University of Liverpool, a member of Liverpool Health Partners, Liverpool, UK.,St. Paul's Eye Unit, Liverpool University Hospitals Foundation Trust, Liverpool, UK
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23
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Schiess N, Villabona-Rueda A, Cottier KE, Huether K, Chipeta J, Stins MF. Pathophysiology and neurologic sequelae of cerebral malaria. Malar J 2020; 19:266. [PMID: 32703204 PMCID: PMC7376930 DOI: 10.1186/s12936-020-03336-z] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Accepted: 07/13/2020] [Indexed: 12/14/2022] Open
Abstract
Cerebral malaria (CM), results from Plasmodium falciparum infection, and has a high mortality rate. CM survivors can retain life-long post CM sequelae, including seizures and neurocognitive deficits profoundly affecting their quality of life. As the Plasmodium parasite does not enter the brain, but resides inside erythrocytes and are confined to the lumen of the brain's vasculature, the neuropathogenesis leading to these neurologic sequelae is unclear and under-investigated. Interestingly, postmortem CM pathology differs in brain regions, such as the appearance of haemorragic punctae in white versus gray matter. Various host and parasite factors contribute to the risk of CM, including exposure at a young age, parasite- and host-related genetics, parasite sequestration and the extent of host inflammatory responses. Thus far, several proposed adjunctive treatments have not been successful in the treatment of CM but are highly needed. The region-specific CM neuro-pathogenesis leading to neurologic sequelae is intriguing, but not sufficiently addressed in research. More attention to this may lead to the development of effective adjunctive treatments to address CM neurologic sequelae.
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Affiliation(s)
- Nicoline Schiess
- Department of Neurology, Johns Hopkins School of Medicine, 600 N. Wolfe St., Meyer 6-113, Baltimore, MD, 21287, USA
| | - Andres Villabona-Rueda
- Malaria Research Institute, Dept Molecular Microbiology Immunology, Johns Hopkins School of Public Health, 615 N Wolfe Street, Baltimore, MD, 21205, USA
| | - Karissa E Cottier
- Malaria Research Institute, Dept Molecular Microbiology Immunology, Johns Hopkins School of Public Health, 615 N Wolfe Street, Baltimore, MD, 21205, USA.,BioIVT, 1450 South Rolling Road, Baltimore, MD, USA
| | | | - James Chipeta
- Department of Paediatrics, University Teaching Hospital, Nationalist Road, Lusaka, Zambia
| | - Monique F Stins
- Malaria Research Institute, Dept Molecular Microbiology Immunology, Johns Hopkins School of Public Health, 615 N Wolfe Street, Baltimore, MD, 21205, USA.
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24
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Vera IM, Kessler A, Ting LM, Harawa V, Keller T, Allen D, Njie M, Moss M, Soko M, Ahmadu A, Kadwala I, Ray S, Nyirenda TS, Mandala WL, Taylor TE, Rogerson SJ, Seydel KB, Kim K. Plasma cell-free DNA predicts pediatric cerebral malaria severity. JCI Insight 2020; 5:136279. [PMID: 32554925 DOI: 10.1172/jci.insight.136279] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Accepted: 05/20/2020] [Indexed: 12/28/2022] Open
Abstract
BACKGROUNDPrediction of adverse outcomes in cerebral malaria (CM) is difficult. We hypothesized that cell-free DNA (cfDNA) levels would facilitate identification of severe and potentially fatal CM cases.METHODSIn this retrospective study, plasma from Malawian children with CM (n = 134), uncomplicated malaria (UM, n = 77), and healthy controls (HC, n = 60) was assayed for cfDNA using a fluorescence assay. Host and parasite cfDNA was measured by quantitative PCR. Immune markers were determined by ELISA, Luminex, or cytometric bead array.RESULTSTotal cfDNA increased with malaria severity (HC versus UM, P < 0.001; HC versus CM, P < 0.0001; UM versus CM, P < 0.0001), was elevated in retinopathy-positive (Ret+) CM relative to Ret- CM (7.66 versus 5.47 ng/μL, P = 0.027), and differentiated Ret+ fatal cases from survivors (AUC 0.779; P < 0.001). cfDNA levels in patients with non-malarial febrile illness (NMF, P = 0.25) and non-malarial coma (NMC, P = 0.99) were comparable with UM. Host DNA, rather than parasite DNA, was the major cfDNA contributor (UM, 268 versus 67 pg/μL; CM, 2824 versus 463 pg/μL). Host and parasite cfDNA distinguished CM by retinopathy (host, AUC 0.715, P = 0.0001; parasite, AUC 0.745, P = 0.0001), but only host cfDNA distinguished fatal cases (AUC 0.715, P = 0.0001). Total cfDNA correlated with neutrophil markers IL-8 (rs = 0.433, P < 0.0001) and myeloperoxidase (rs = 0.683, P < 0.0001).CONCLUSIONQuantifying plasma cfDNA is a simple assay useful in identifying children at risk for fatal outcome and has promise as a point-of-care assay. Elevated cfDNA suggests a link with host inflammatory pathways in fatal CM.FUNDINGNIH NCATS (AK), Burroughs-Wellcome (AK), and National Health and Medical Research Council of Australia (SJR).
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Affiliation(s)
- Iset Medina Vera
- Morsani College of Medicine, University of South Florida, Tampa, Florida, USA
| | - Anne Kessler
- Albert Einstein College of Medicine, Bronx, New York, USA
| | - Li-Min Ting
- Morsani College of Medicine, University of South Florida, Tampa, Florida, USA.,Albert Einstein College of Medicine, Bronx, New York, USA
| | - Visopo Harawa
- Blantyre Malaria Project, University of Malawi College of Medicine, Blantyre, Malawi
| | - Thomas Keller
- Morsani College of Medicine, University of South Florida, Tampa, Florida, USA
| | - Dylan Allen
- Morsani College of Medicine, University of South Florida, Tampa, Florida, USA
| | - Madi Njie
- Department of Medicine, University of Melbourne, Melbourne, Victoria, Australia
| | - McKenze Moss
- Xavier University of Louisiana, New Orleans, Louisiana, USA
| | - Monica Soko
- College of Medicine, University of Malawi, Blantyre, Malawi
| | - Ajisa Ahmadu
- Malawi-Liverpool Wellcome Trust Clinical Research Programme, Blantyre, Malawi
| | | | - Stephen Ray
- Blantyre Malaria Project, University of Malawi College of Medicine, Blantyre, Malawi.,Malawi-Liverpool Wellcome Trust Clinical Research Programme, Blantyre, Malawi
| | - Tonney S Nyirenda
- College of Medicine, University of Malawi, Blantyre, Malawi.,Malawi-Liverpool Wellcome Trust Clinical Research Programme, Blantyre, Malawi
| | - Wilson L Mandala
- Malawi-Liverpool Wellcome Trust Clinical Research Programme, Blantyre, Malawi.,Malawi University of Science and Technology, Thyolo, Malawi
| | - Terrie E Taylor
- Blantyre Malaria Project, University of Malawi College of Medicine, Blantyre, Malawi.,College of Osteopathic Medicine, Michigan State University, East Lansing, Michigan, USA
| | - Stephen J Rogerson
- Department of Medicine, University of Melbourne, Melbourne, Victoria, Australia
| | - Karl B Seydel
- Blantyre Malaria Project, University of Malawi College of Medicine, Blantyre, Malawi.,College of Osteopathic Medicine, Michigan State University, East Lansing, Michigan, USA
| | - Kami Kim
- Morsani College of Medicine, University of South Florida, Tampa, Florida, USA.,Albert Einstein College of Medicine, Bronx, New York, USA
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25
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Riggle BA, Miller LH, Pierce SK. Desperately Seeking Therapies for Cerebral Malaria. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2020; 204:327-334. [PMID: 31907275 PMCID: PMC6951433 DOI: 10.4049/jimmunol.1900829] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Accepted: 09/10/2019] [Indexed: 02/07/2023]
Abstract
Malaria is a deadly infectious disease caused by parasites of the Plasmodium spp. that takes an estimated 435,000 lives each year, primarily among young African children. For most children, malaria is a febrile illness that resolves with time, but in ∼1% of cases, for reasons we do not understand, malaria becomes severe and life threatening. Cerebral malaria (CM) is the most common form of severe malaria, accounting for the vast majority of childhood deaths from malaria despite highly effective antiparasite chemotherapy. Thus, CM is one of the most prevalent lethal brain diseases, and one for which we have no effective therapy. CM is, in part, an immune-mediated disease, and to fully understand CM, it is essential to appreciate the complex relationship between the malarial parasite and the human immune system. In this study, we provide a primer on malaria for immunologists and, in this context, review progress identifying targets for therapeutic intervention.
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Affiliation(s)
- Brittany A Riggle
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852; and
| | - Louis H Miller
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852
| | - Susan K Pierce
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852; and
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26
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Dobbs KR, Crabtree JN, Dent AE. Innate immunity to malaria-The role of monocytes. Immunol Rev 2020; 293:8-24. [PMID: 31840836 PMCID: PMC6986449 DOI: 10.1111/imr.12830] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 11/19/2019] [Accepted: 11/25/2019] [Indexed: 12/12/2022]
Abstract
Monocytes are innate immune cells essential for host protection against malaria. Upon activation, monocytes function to help reduce parasite burden through phagocytosis, cytokine production, and antigen presentation. However, monocytes have also been implicated in the pathogenesis of severe disease through production of damaging inflammatory cytokines, resulting in systemic inflammation and vascular dysfunction. Understanding the molecular pathways influencing the balance between protection and pathology is critical. In this review, we discuss recent data regarding the role of monocytes in human malaria, including studies of innate sensing of the parasite, immunometabolism, and innate immune training. Knowledge gained from these studies may guide rational development of novel antimalarial therapies and inform vaccine development.
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Affiliation(s)
- Katherine R. Dobbs
- Center for Global Health and Diseases, Case Western Reserve University, Cleveland, OH, USA
- Division of Pediatric Infectious Diseases, University Hospitals Rainbow Babies and Children’s Hospital, Cleveland, OH, USA
| | - Juliet N. Crabtree
- Department of Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Arlene E. Dent
- Center for Global Health and Diseases, Case Western Reserve University, Cleveland, OH, USA
- Division of Pediatric Infectious Diseases, University Hospitals Rainbow Babies and Children’s Hospital, Cleveland, OH, USA
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27
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Darling TK, Mimche PN, Bray C, Umaru B, Brady LM, Stone C, Eboumbou Moukoko CE, Lane TE, Ayong LS, Lamb TJ. EphA2 contributes to disruption of the blood-brain barrier in cerebral malaria. PLoS Pathog 2020; 16:e1008261. [PMID: 31999807 PMCID: PMC6991964 DOI: 10.1371/journal.ppat.1008261] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Accepted: 12/07/2019] [Indexed: 01/01/2023] Open
Abstract
Disruption of blood-brain barrier (BBB) function is a key feature of cerebral malaria. Increased barrier permeability occurs due to disassembly of tight and adherens junctions between endothelial cells, yet the mechanisms governing junction disassembly and vascular permeability during cerebral malaria remain poorly characterized. We found that EphA2 is a principal receptor tyrosine kinase mediating BBB breakdown during Plasmodium infection. Upregulated on brain microvascular endothelial cells in response to inflammatory cytokines, EphA2 is required for the loss of junction proteins on mouse and human brain microvascular endothelial cells. Furthermore, EphA2 is necessary for CD8+ T cell brain infiltration and subsequent BBB breakdown in a mouse model of cerebral malaria. Blocking EphA2 protects against BBB breakdown highlighting EphA2 as a potential therapeutic target for cerebral malaria.
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Affiliation(s)
- Thayer K. Darling
- Department of Pathology, University of Utah, Salt Lake City, UT, United States of America
- Department of Pediatric Infectious Diseases, Emory University School of Medicine, Atlanta, GA, United States of America
| | - Patrice N. Mimche
- Department of Pathology, University of Utah, Salt Lake City, UT, United States of America
| | - Christian Bray
- Department of Pediatric Infectious Diseases, Emory University School of Medicine, Atlanta, GA, United States of America
| | - Banlanjo Umaru
- Malaria Research Unit, Centre Pasteur du Cameroun, Yaoundé, Cameroon
| | - Lauren M. Brady
- Department of Pediatric Infectious Diseases, Emory University School of Medicine, Atlanta, GA, United States of America
| | - Colleen Stone
- Department of Pathology, University of Utah, Salt Lake City, UT, United States of America
| | - Carole Else Eboumbou Moukoko
- Malaria Research Unit, Centre Pasteur du Cameroun, Yaoundé, Cameroon
- Department of Biological Sciences, University of Douala, Douala, Cameroon
| | - Thomas E. Lane
- Department of Pathology, University of Utah, Salt Lake City, UT, United States of America
| | - Lawrence S. Ayong
- Malaria Research Unit, Centre Pasteur du Cameroun, Yaoundé, Cameroon
| | - Tracey J. Lamb
- Department of Pathology, University of Utah, Salt Lake City, UT, United States of America
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28
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CD14 + monocytes are the main leucocytic sources of CXCL10 in response to Plasmodium falciparum. Parasitology 2019; 147:465-470. [PMID: 31831089 DOI: 10.1017/s0031182019001744] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The CXCR3 chemokine CXCL10 or IFN-γ inducible protein 10 (IP-10) has been identified as an important biomarker of cerebral malaria (CM) mortality in children. Studies in mouse malaria infection models have shown that CXCL10 blockade alleviates brain intravascular inflammation and protects infected mice from CM. Despite the key role that CXCL10 plays in the development of CM, the leucocytic sources of CXCL10 in response to human malaria are not known. Here we investigated CXCL10 responses to Plasmodium falciparum in peripheral blood mononuclear cells (PBMCs). We found that PBMCs from malaria-unexposed donors produce CXCL10 in response to P. falciparum and that this response is IFN-γ-dependent. Moreover, CD14+ monocytes were identified as the main leucocytic sources of CXCL10 in peripheral blood, suggesting an important role for innate immune responses in the activation of this pathway involved in the development of symptomatic malaria.
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29
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Avril M, Benjamin M, Dols MM, Smith JD. Interplay of Plasmodium falciparum and thrombin in brain endothelial barrier disruption. Sci Rep 2019; 9:13142. [PMID: 31511575 PMCID: PMC6739390 DOI: 10.1038/s41598-019-49530-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 08/19/2019] [Indexed: 01/05/2023] Open
Abstract
Recent concepts suggest that both Plasmodium falciparum factors and coagulation contribute to endothelial activation and dysfunction in pediatric cerebral malaria (CM) pathology. However, there is still limited understanding of how these complex inflammatory stimuli are integrated by brain endothelial cells. In this study, we examined how mature-stage P. falciparum infected erythrocytes (IE) interact with tumor necrosis factor α (TNFα) and thrombin in the activation and permeability of primary human brain microvascular endothelial cell (HBMEC) monolayers. Whereas trophozoite-stage P. falciparum-IE have limited effect on the viability of HBMEC or the secretion of pro-inflammatory cytokines or chemokines, except at super physiological parasite-host cell ratios, schizont-stage P. falciparum-IE induced low levels of cell death. Additionally, schizont-stage parasites were more barrier disruptive than trophozoite-stage P. falciparum-IE and prolonged thrombin-induced barrier disruption in both resting and TNFα-activated HBMEC monolayers. These results provide evidence that parasite products and thrombin may interact to increase brain endothelial permeability.
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Affiliation(s)
- Marion Avril
- Seattle Children's Research Institute, Seattle, WA, 98109, USA
| | - Max Benjamin
- Seattle Children's Research Institute, Seattle, WA, 98109, USA
| | | | - Joseph D Smith
- Seattle Children's Research Institute, Seattle, WA, 98109, USA. .,Department of Global Health, University of Washington, Seattle, WA, 98195, USA.
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30
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Shen SS, Qu XY, Zhang WZ, Li J, Lv ZY. Infection against infection: parasite antagonism against parasites, viruses and bacteria. Infect Dis Poverty 2019; 8:49. [PMID: 31200765 PMCID: PMC6570864 DOI: 10.1186/s40249-019-0560-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Accepted: 05/28/2019] [Indexed: 12/21/2022] Open
Abstract
Background Infectious diseases encompass a large spectrum of diseases that threaten human health, and coinfection is of particular importance because pathogen species can interact within the host. Currently, the antagonistic relationship between different pathogens during concurrent coinfections is defined as one in which one pathogen either manages to inhibit the invasion, development and reproduction of the other pathogen or biologically modulates the vector density. In this review, we provide an overview of the phenomenon and mechanisms of antagonism of coinfecting pathogens involving parasites. Main body This review summarizes the antagonistic interaction between parasites and parasites, parasites and viruses, and parasites and bacteria. At present, relatively clear mechanisms explaining polyparasitism include apparent competition, exploitation competition, interference competition, biological control of intermediate hosts or vectors and suppressive effect on transmission. In particular, immunomodulation, including the suppression of dendritic cell (DC) responses, activation of basophils and mononuclear macrophages and adjuvant effects of the complement system, is described in detail. Conclusions In this review, we summarize antagonistic concurrent infections involving parasites and provide a functional framework for in-depth studies of the underlying mechanisms of coinfection with different microorganisms, which will hasten the development of promising antimicrobial alternatives, such as novel antibacterial vaccines or biological methods of controlling infectious diseases, thus relieving the overwhelming burden of ever-increasing antimicrobial resistance. Electronic supplementary material The online version of this article (10.1186/s40249-019-0560-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Shi-Shi Shen
- Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, China.,Key Laboratory of Tropical Disease Control, Ministry of Education, Sun Yat-sen University, Guangzhou, China.,Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, China
| | - Xiao-Yan Qu
- Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, China.,Key Laboratory of Tropical Disease Control, Ministry of Education, Sun Yat-sen University, Guangzhou, China.,Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, China
| | - Wei-Zhe Zhang
- Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, China.,Key Laboratory of Tropical Disease Control, Ministry of Education, Sun Yat-sen University, Guangzhou, China.,Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, China
| | - Jian Li
- Fifth Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, ZhuHai, Guangdong, China
| | - Zhi-Yue Lv
- Fifth Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, ZhuHai, Guangdong, China. .,Key Laboratory of Tropical Disease Control, Ministry of Education, Sun Yat-sen University, Guangzhou, China. .,Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, China.
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31
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Blood-Brain Barrier in Cerebral Malaria: Pathogenesis and Therapeutic Intervention. Trends Parasitol 2019; 35:516-528. [PMID: 31147271 DOI: 10.1016/j.pt.2019.04.010] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Revised: 04/25/2019] [Accepted: 04/25/2019] [Indexed: 02/06/2023]
Abstract
Cerebral malaria is a life-threatening complication of malaria caused by the parasite Plasmodium falciparum. The growing problem of drug resistance and the dearth of new antiparasitic drugs are a serious threat to the antimalaria treatment regimes. Studies on humans and the murine model have implicated the disruption of the blood-brain barrier (BBB) in the lethal course of the disease. Therefore, efforts to alleviate the BBB dysfunction could serve as an adjunct therapy. Here, we review the mechanisms associated with the disruption of the BBB. In addition, we discuss the current, still limited, knowledge on the contribution of different cell types, microparticles, and the kynurenine pathway in the regulation of BBB dysfunction, and how these molecules could be used as potential new therapeutic targets.
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32
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Sierro F, Grau GER. The Ins and Outs of Cerebral Malaria Pathogenesis: Immunopathology, Extracellular Vesicles, Immunometabolism, and Trained Immunity. Front Immunol 2019; 10:830. [PMID: 31057552 PMCID: PMC6478768 DOI: 10.3389/fimmu.2019.00830] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2018] [Accepted: 03/28/2019] [Indexed: 12/16/2022] Open
Abstract
Complications from malaria parasite infections still cost the lives of close to half a million people every year. The most severe is cerebral malaria (CM). Employing murine models of CM, autopsy results, in vitro experiments, neuroimaging and microscopic techniques, decades of research activity have investigated the development of CM immunopathology in the hope of identifying steps that could be therapeutically targeted. Yet important questions remain. This review summarizes recent findings, primarily mechanistic insights on the essential cellular and molecular players involved gained within the murine experimental cerebral malaria model. It also highlights recent developments in (a) cell-cell communication events mediated through extracellular vesicles (EVs), (b) mounting evidence for innate immune memory, leading to “trained“ increased or tolerised responses, and (c) modulation of immune cell function through metabolism, that could shed light on why some patients develop this life-threatening condition whilst many do not.
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Affiliation(s)
- Frederic Sierro
- Vascular Immunology Unit, Department of Pathology, Faculty of Medicine and Health, School of Medical Sciences, The University of Sydney, Sydney, NSW, Australia.,Human Health, Nuclear Science, Technology, and Landmark Infrastructure, Australian Nuclear Science and Technology Organisation, Sydney, NSW, Australia
| | - Georges E R Grau
- Vascular Immunology Unit, Department of Pathology, Faculty of Medicine and Health, School of Medical Sciences, The University of Sydney, Sydney, NSW, Australia
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33
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Mandala WL, Gondwe EN, Nyirenda TS, Drayson M, Molyneux ME, MacLennan CA. HIV infection compounds the lymphopenia associated with cerebral malaria in Malawian children. J Blood Med 2018; 10:9-18. [PMID: 30588141 PMCID: PMC6305159 DOI: 10.2147/jbm.s187081] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Aim Cerebral malaria (CM), unlike severe malarial anemia (SMA), has previously been characterized by pan-lymphopenia that normalizes in convalescence, while HIV infection is associated with depletion of CD4+ T cells. In this study, we investigate whether HIV infection in Malawian children exacerbates the pan-lymphopenia associated with CM. Methods We investigated the absolute and percentage lymphocyte-subset counts and their activation and memory status in Malawian children presenting with either CM who were HIV-uninfected (n=29), HIV-infected (n=9), or SMA who were HIV-uninfected (n=30) and HIV-infected (n=5) in comparison with HIV-uninfected children without malaria (n=42) and HIV-infected children without malaria (n=4). Results HIV-infected CM cases had significantly lower absolute counts of T cells (P=0.006), CD4+ T cells (P=0.0008), and B cells (P=0.0014) than HIV-uninfected CM cases, and significantly lower percentages of CD4+ T cells than HIV-uninfected CM cases (P=0.005). HIV-infected SMA cases had significantly lower percentages of CD4+ T cells (P=0.001) and higher CD8+ T cells (P=0.003) in comparison with HIV-uninfected SMA cases. HIV-infected SMA cases had higher proportions of activated T cells (P=0.003) expressing CD69 than HIV-uninfected SMA cases. Conclusion HIV infection compounds the perturbation of acute CM and SMA on lymphocytes, exacerbating subset-specific lymphopenia in CM and increasing activation status in SMA, potentially exacerbating host immunocompromise.
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Affiliation(s)
- Wilson L Mandala
- Malawi Liverpool Wellcome Trust Clinical Research Programme, College of Medicine, Blantyre, Malawi, .,Biomedical Sciences Department, College of Medicine, Blantyre, Malawi, .,Academy of Medical Sciences, Malawi University of Science and Technology, Thyolo, Malawi,
| | - Esther N Gondwe
- Malawi Liverpool Wellcome Trust Clinical Research Programme, College of Medicine, Blantyre, Malawi,
| | - Tonney S Nyirenda
- Malawi Liverpool Wellcome Trust Clinical Research Programme, College of Medicine, Blantyre, Malawi, .,Pathology Department, College of Medicine, Blantyre, Malawi
| | - Mark Drayson
- Institute of Immunology and Immunotherapy, College of Medicine and Dental Sciences, University of Birmingham, Birmingham, UK
| | - Malcolm E Molyneux
- Malawi Liverpool Wellcome Trust Clinical Research Programme, College of Medicine, Blantyre, Malawi, .,Liverpool School of Tropical Medicine, Liverpool, UK
| | - Calman A MacLennan
- Malawi Liverpool Wellcome Trust Clinical Research Programme, College of Medicine, Blantyre, Malawi, .,Jenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
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34
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Thiam A, Baaklini S, Mbengue B, Nisar S, Diarra M, Marquet S, Fall MM, Sanka M, Thiam F, Diallo RN, Torres M, Dieye A, Rihet P. NCR3 polymorphism, haematological parameters, and severe malaria in Senegalese patients. PeerJ 2018; 6:e6048. [PMID: 30533319 PMCID: PMC6282937 DOI: 10.7717/peerj.6048] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Accepted: 10/31/2018] [Indexed: 12/12/2022] Open
Abstract
Background Host factors, including host genetic variation, have been shown to influence the outcome of Plasmodium falciparum infection. Genome-wide linkage studies have mapped mild malaria resistance genes on chromosome 6p21, whereas NCR3-412 polymorphism (rs2736191) lying within this region was found to be associated with mild malaria. Methods Blood samples were taken from 188 Plasmodium falciparum malaria patients (76 mild malaria patients, 85 cerebral malaria patients, and 27 severe non-cerebral malaria patients). NCR3-412 (rs2736191) was analysed by sequencing, and haematological parameters were measured. Finally, their association with clinical phenotypes was assessed. Results We evidenced an association of thrombocytopenia with both cerebral malaria and severe non-cerebral malaria, and of an association of high leukocyte count with cerebral malaria. Additionally, we found no association of NCR3-412 with either cerebral malaria, severe non-cerebral malaria, or severe malaria after grouping cerebral malaria and severe non-cerebral malaria patients. Conclusions Our results suggest that NCR3 genetic variation has no effect, or only a small effect on the occurrence of severe malaria, although it has been strongly associated with mild malaria. We discuss the biological meaning of these results. Besides, we confirmed the association of thrombocytopenia and high leukocyte count with severe malaria phenotypes.
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Affiliation(s)
- Alassane Thiam
- Unité d'Immunogénétique, Institut Pasteur de Dakar, Dakar, Senegal
| | | | - Babacar Mbengue
- Service d'Immunologie, University Cheikh Anta Diop of Dakar, Dakar, Senegal
| | - Samia Nisar
- Aix Marseille Univ, INSERM, TAGC, Marseille, France
| | - Maryam Diarra
- G4 Biostatistique, Institut Pasteur de Dakar, Dakar, Sénégal
| | | | | | - Michel Sanka
- Aix Marseille Univ, INSERM, TAGC, Marseille, France
| | - Fatou Thiam
- Unité d'Immunogénétique, Institut Pasteur de Dakar, Dakar, Senegal
| | | | | | - Alioune Dieye
- Unité d'Immunogénétique, Institut Pasteur de Dakar, Dakar, Senegal.,Service d'Immunologie, University Cheikh Anta Diop of Dakar, Dakar, Senegal
| | - Pascal Rihet
- Aix Marseille Univ, INSERM, TAGC, Marseille, France
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35
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Ortega-Pajares A, Rogerson SJ. The Rough Guide to Monocytes in Malaria Infection. Front Immunol 2018; 9:2888. [PMID: 30581439 PMCID: PMC6292935 DOI: 10.3389/fimmu.2018.02888] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Accepted: 11/26/2018] [Indexed: 12/14/2022] Open
Abstract
While half of the world's population is at risk of malaria, the most vulnerable are still children under five, pregnant women and returning travelers. Anopheles mosquitoes transmit malaria parasites to the human host; but how Plasmodium interact with the innate immune system remains largely unexplored. The most recent advances prove that monocytes are a key component to control parasite burden and to protect host from disease. Monocytes' protective roles include phagocytosis, cytokine production and antigen presentation. However, monocytes can be involved in pathogenesis and drive inflammation and sequestration of infected red blood cells in organs such as the brain, placenta or lungs by secreting cytokines that upregulate expression of endothelial adhesion receptors. Plasmodium DNA, hemozoin or extracellular vesicles can impair the function of monocytes. With time, reinfections with Plasmodium change the relative proportion of monocyte subsets and their physical properties. These changes relate to clinical outcomes and might constitute informative biomarkers of immunity. More importantly, at the molecular level, transcriptional, metabolic or epigenetic changes can “prime” monocytes to alter their responses in future encounters with Plasmodium. This mechanism, known as trained immunity, challenges the traditional view of monocytes as a component of the immune system that lacks memory. Overall, this rough guide serves as an update reviewing the advances made during the past 5 years on understanding the role of monocytes in innate immunity to malaria.
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Affiliation(s)
- Amaya Ortega-Pajares
- Department of Medicine at Royal Melbourne Hospital, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VIC, Australia
| | - Stephen J Rogerson
- Department of Medicine at Royal Melbourne Hospital, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VIC, Australia
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36
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Harawa V, Njie M, Kessler A, Choko A, Kumwenda B, Kampondeni S, Potchen M, Kim K, Jaworowski A, Taylor T, Mandala W, Seydel K, Rogerson S. Brain swelling is independent of peripheral plasma cytokine levels in Malawian children with cerebral malaria. Malar J 2018; 17:435. [PMID: 30477519 PMCID: PMC6260579 DOI: 10.1186/s12936-018-2590-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Accepted: 11/22/2018] [Indexed: 11/26/2022] Open
Abstract
Background Cerebral malaria (CM) is often fatal, and severe brain swelling is a predictor of CM-related mortality. CM is characterized by elevated circulating pro-inflammatory cytokines TNF and IFN-γ and anti-inflammatory cytokine IL-10, however whether cytokine levels correlate with brain swelling severity is unknown. This study therefore was conducted to investigate the relationship between cytokine levels and brain swelling severity in children presenting with CM. Methods A total of 195 Malawian children presenting with CM were recruited and had the concentrations of plasma cytokines determined and compared to brain swelling severity, determined by MRI examination, and graded as severe, moderate, mild or none. Results Levels of IL-1β, IL-6, IL-8 and IL-10 did not differ between CM patients with and without severe brain swelling. Compared to children without brain swelling, IL-12 levels were higher in children with severe swelling (p < 0.01, no swelling 1 pg/mL, IQR [1] vs. severe swelling 18.7 pg/mL, IQR [1–27]), whereas TNF concentrations were higher in children with moderate brain swelling compared to children with no swelling (p < 0.01, no swelling 3 pg/mL, IQR [1–20] vs. moderate swelling 24 pg/mL, IQR [8–58]. Multivariate analysis showed that no single cytokine independently predicted brain swelling. Conclusion Severe brain swelling in paediatric CM was independent of tested blood pro-inflammatory and anti-inflammatory cytokines which are markers of systemic inflammation. Electronic supplementary material The online version of this article (10.1186/s12936-018-2590-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Visopo Harawa
- Biomedical Sciences Department, College of Medicine, University of Malawi, Blantyre, Malawi. .,Malawi-Liverpool Wellcome Trust Clinical Programme, Blantyre, Malawi.
| | - Madi Njie
- Department of Medicine at the Doherty Institute, University of Melbourne, Melbourne, Australia
| | - Anne Kessler
- Albert Einstein College of Medicine, Bronx, NY, USA
| | - Augustine Choko
- Biomedical Sciences Department, College of Medicine, University of Malawi, Blantyre, Malawi.,London School of Hygiene & Tropical Medicine, London, UK
| | - Benjamin Kumwenda
- Biomedical Sciences Department, College of Medicine, University of Malawi, Blantyre, Malawi.,Malawi-Liverpool Wellcome Trust Clinical Programme, Blantyre, Malawi
| | - Sam Kampondeni
- Blantyre Malaria Project, University of Malawi College of Medicine, Blantyre, Malawi
| | | | - Kami Kim
- Albert Einstein College of Medicine, Bronx, NY, USA.,University of South Florida, Tampa, FL, USA
| | - Anthony Jaworowski
- Life Sciences Program, Burnet Institute, Melbourne, Australia.,Health and Biomedical Sciences, RMIT University, Melbourne, Australia
| | - Terrie Taylor
- Blantyre Malaria Project, University of Malawi College of Medicine, Blantyre, Malawi.,Department of Osteopathic Medical Specialties, College of Osteopathic Medicine, Michigan State University, E. Lansing, MI, USA
| | - Wilson Mandala
- Biomedical Sciences Department, College of Medicine, University of Malawi, Blantyre, Malawi. .,Malawi-Liverpool Wellcome Trust Clinical Programme, Blantyre, Malawi. .,Academy of Medical Sciences, Malawi University of Science and Technology, Thyolo, Malawi.
| | - Karl Seydel
- Blantyre Malaria Project, University of Malawi College of Medicine, Blantyre, Malawi.,Department of Osteopathic Medical Specialties, College of Osteopathic Medicine, Michigan State University, E. Lansing, MI, USA
| | - Stephen Rogerson
- Department of Medicine at the Doherty Institute, University of Melbourne, Melbourne, Australia
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37
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Munyenyembe AU, Gausi K, Nyirenda TS, Hiestand J, Mallewa J, Mandala WL. HIV infection has a profound effect on hematological factors but not on electrolyte profile of Malawian adults presenting with uncomplicated malaria and severe malaria. J Blood Med 2018; 9:153-162. [PMID: 30323699 PMCID: PMC6178338 DOI: 10.2147/jbm.s172869] [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] [Indexed: 12/12/2022] Open
Abstract
Aim Although malaria and HIV infections independently affect the electrolyte and hematologic profiles, little is known of how these profiles are affected in individuals coinfected with malaria and HIV. We therefore conducted this study to investigate the electrolyte and hematologic profiles of Malawian adults presenting with either uncomplicated malaria (UM), severe malaria (SM), and those presenting with HIV and UM or HIV and SM. Methods Study participants were recruited at Queen Elizabeth Central Hospital, and malaria infection was confirmed by rapid diagnostic test and malaria slides, and full blood count, HIV, and wet chemistries were analyzed. Results Sodium, potassium, calcium, and chloride levels of all 4 study groups were similar to those of healthy controls. Both HIV-infected groups (UM and SM) had lower red blood cell counts and lower hemoglobin concentration than the reference range. Platelet counts were lower in both HIV-uninfected SM cases (64×109/L) and in the HIV-infected SM cases (66×109/L) compared to the reference range (115–290×109/L). HIV− UM cases had higher proportion and absolute counts of neutrophils and white blood cell counts compared to the HIV+ UM cases. Conclusion HIV infection did not affect the electrolyte profile of Malawian adults presenting with UM or SM but had an effect on red blood cells, Hb concentration, neutrophils, and platelet counts.
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Affiliation(s)
| | - Kamunkhwala Gausi
- Malawi-Liverpool Wellcome Trust, Malaria Immunology Department, Blantyre, Malawi, ,
| | | | | | - Jane Mallewa
- Medicine Department, College of Medicine, Blantyre, Malawi
| | - Wilson L Mandala
- Malawi-Liverpool Wellcome Trust, Malaria Immunology Department, Blantyre, Malawi, , .,Academy of Medical Sciences, Biological Sciences Department, Malawi University of Science & Technology, Thyolo, Malawi,
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38
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Ghazanfari N, Mueller SN, Heath WR. Cerebral Malaria in Mouse and Man. Front Immunol 2018; 9:2016. [PMID: 30250468 PMCID: PMC6139318 DOI: 10.3389/fimmu.2018.02016] [Citation(s) in RCA: 84] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Accepted: 08/15/2018] [Indexed: 12/18/2022] Open
Abstract
Cerebral malaria (CM) is an acute encephalopathy caused by the malaria parasite Plasmodium falciparum, which develops in a small minority of infected patients and is responsible for the majority of deaths in African children. Despite decades of research on CM, the pathogenic mechanisms are still relatively poorly defined. Nevertheless, many studies in recent years, using a combination of animal models, in vitro cell culture work, and human patients, provide significant insight into the pathologic mechanisms leading to CM. In this review, we summarize recent findings from mouse models and human studies on the pathogenesis of CM, understanding of which may enable development of novel therapeutic approaches.
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Affiliation(s)
- Nazanin Ghazanfari
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VIC, Australia.,The ARC Centre of Excellence in Advanced Molecular Imaging, University of Melbourne, Melbourne, VIC, Australia
| | - Scott N Mueller
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VIC, Australia.,The ARC Centre of Excellence in Advanced Molecular Imaging, University of Melbourne, Melbourne, VIC, Australia
| | - William R Heath
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VIC, Australia.,The ARC Centre of Excellence in Advanced Molecular Imaging, University of Melbourne, Melbourne, VIC, Australia
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39
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Kwenti TE. Malaria and HIV coinfection in sub-Saharan Africa: prevalence, impact, and treatment strategies. Res Rep Trop Med 2018; 9:123-136. [PMID: 30100779 PMCID: PMC6067790 DOI: 10.2147/rrtm.s154501] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Malaria and HIV, two of the world's most deadly diseases, are widespread, but their distribution overlaps greatly in sub-Saharan Africa. Consequently, malaria and HIV coinfection (MHC) is common in the region. In this paper, pertinent publications on the prevalence, impact, and treatment strategies of MHC obtained by searching major electronic databases (PubMed, PubMed Central, Google Scholar, ScienceDirect, and Scopus) were reviewed, and it was found that the prevalence of MHC in SSA was 0.7%-47.5% overall. Prevalence was 0.7%-47.5% in nonpregnant adults, 1.2%-27.8% in children, and 0.94%-37% in pregnant women. MHC was associated with an increased frequency of clinical parasitemia and severe malaria, increased parasite and viral load, and impaired immunity to malaria in nonpregnant adults, children, and pregnant women, increased in placental malaria and related outcomes in pregnant women, and impaired antimalarial drug efficacy in nonpregnant adults and pregnant women. Although a few cases of adverse events have been reported in coinfected patients receiving antimalarial and antiretroviral drugs concurrently, available data are very limited and have not prompted major revision in treatment guidelines for both diseases. Artemisinin-based combination therapy and cotrimoxazole are currently the recommended drugs for treatment and prevention of malaria in HIV-infected children and adults. However, concurrent administration of cotrimoxazole and sulfadoxine-pyrimethamine in HIV-infected pregnant women is not recommended, because of high risk of sulfonamide toxicity. Further research is needed to enhance our understanding of the impact of malaria on HIV, drug-drug interactions in patients receiving antimalarials and antiretroviral drugs concomitantly, and the development of newer, safer, and more cost-effective drugs and vaccines to prevent malaria in HIV-infected pregnant women.
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Affiliation(s)
- Tebit E Kwenti
- Department of Medical Laboratory Sciences, Faculty of Health Sciences, University of Buea,
- Regional Hospital Buea, Buea, Cameroon,
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40
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TCRβ-expressing macrophages induced by a pathogenic murine malaria correlate with parasite burden and enhanced phagocytic activity. PLoS One 2018; 13:e0201043. [PMID: 30044851 PMCID: PMC6059462 DOI: 10.1371/journal.pone.0201043] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Accepted: 07/06/2018] [Indexed: 11/19/2022] Open
Abstract
Macrophages express a wide array of invariant receptors that facilitate host defense and mediate pathogenesis during pathogen invasion. We report on a novel population of CD11bhighCD14+F4/80+ macrophages that express TCRβ. This population expands dramatically during a Plasmodium berghei ANKA infection and sequesters in the brain during experimental cerebral malaria. Importantly, measurement of TCRβ transcript and protein levels in macrophages in wildtype versus nude and Rag1 knockout mice establishes that the observed expression is not a consequence of passive receptor expression due to phagocytosis or trogocytosis of peripheral T cells or nonspecific antibody staining to an Fc receptor or cross reactive epitope. We also demonstrate that TCRβ on brain sequestered macrophages undergoes productive gene rearrangements and shows preferential Vβ usage. Remarkably, there is a significant correlation in the proportion of macrophages that express TCRβ and peripheral parasitemia. In addition, presence of TCRβ on the macrophage also correlates with a significant increase (1.9 fold) in the phagocytosis of parasitized erythrocytes. By transcriptional profiling, we identify a novel set of genes and pathways that associate with TCRβ expression by the macrophage. Expansion of TCRβ-expressing macrophages points towards a convergence of the innate and adaptive immune responses where both arms of the immune system cooperate to modulate the host response to malaria and possibly other infections.
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41
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Wilson KD, Ochoa LF, Solomon OD, Pal R, Cardona SM, Carpio VH, Keiser PH, Cardona AE, Vargas G, Stephens R. Elimination of intravascular thrombi prevents early mortality and reduces gliosis in hyper-inflammatory experimental cerebral malaria. J Neuroinflammation 2018; 15:173. [PMID: 29866139 PMCID: PMC5987620 DOI: 10.1186/s12974-018-1207-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Accepted: 05/17/2018] [Indexed: 01/28/2023] Open
Abstract
BACKGROUND Cerebral malaria (CM) is the most lethal outcome of Plasmodium infection. There are clear correlations between expression of inflammatory cytokines, severe coagulopathies, and mortality in human CM. However, the mechanisms intertwining the coagulation and inflammation pathways, and their roles in CM, are only beginning to be understood. In mice with T cells deficient in the regulatory cytokine IL-10 (IL-10 KO), infection with Plasmodium chabaudi leads to a hyper-inflammatory response and lethal outcome that can be prevented by anti-TNF treatment. However, inflammatory T cells are adherent within the vasculature and not present in the brain parenchyma, suggesting a novel form of cerebral inflammation. We have previously documented behavioral dysfunction and microglial activation in infected IL-10 KO animals suggestive of neurological involvement driven by inflammation. In order to understand the relationship of intravascular inflammation to parenchymal dysfunction, we studied the congestion of vessels with leukocytes and fibrin(ogen) and the relationship of glial cell activation to congested vessels in the brains of P. chabaudi-infected IL-10 KO mice. METHODS Using immunofluorescence microscopy, we describe severe thrombotic congestion in these animals. We stained for immune cell surface markers (CD45, CD11b, CD4), fibrin(ogen), microglia (Iba-1), and astrocytes (GFAP) in the brain at the peak of behavioral symptoms. Finally, we investigated the roles of inflammatory cytokine tumor necrosis factor (TNF) and coagulation on the pathology observed using neutralizing antibodies and low-molecular weight heparin to inhibit both inflammation and coagulation, respectively. RESULTS Many blood vessels in the brain were congested with thrombi containing adherent leukocytes, including CD4 T cells and monocytes. Despite containment of the pathogen and leukocytes within the vasculature, activated microglia and astrocytes were prevalent in the parenchyma, particularly clustered near vessels with thrombi. Neutralization of TNF, or the coagulation cascade, significantly reduced both thrombus formation and gliosis in P. chabaudi-infected IL-10 KO mice. CONCLUSIONS These findings support the contribution of cytokines, coagulation, and leukocytes within the brain vasculature to neuropathology in malaria infection. Strikingly, localization of inflammatory leukocytes within intravascular clots suggests a mechanism for interaction between the two cascades by which cytokines drive local inflammation without considerable cellular infiltration into the brain parenchyma.
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Affiliation(s)
- Kyle D Wilson
- Department of Microbiology and Immunology, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX, 77555, USA
| | - Lorenzo F Ochoa
- Center for Biomedical Engineering, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX, 77555, USA
| | - Olivia D Solomon
- Center for Biomedical Engineering, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX, 77555, USA
| | - Rahul Pal
- Center for Biomedical Engineering, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX, 77555, USA
| | - Sandra M Cardona
- Department of Biology, One UTSA Circle, University of Texas at San Antonio, San Antonio, TX, 78249, USA
| | - Victor H Carpio
- Department of Microbiology and Immunology, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX, 77555, USA
| | - Philip H Keiser
- Department of Internal Medicine, Division of Infectious Diseases, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX, 77555-0435, USA
| | - Astrid E Cardona
- Department of Biology, One UTSA Circle, University of Texas at San Antonio, San Antonio, TX, 78249, USA
| | - Gracie Vargas
- Center for Biomedical Engineering, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX, 77555, USA.,Department of Neuroscience and Cell Biology, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX, 77555, USA.,Institute for Human Infections and Immunity, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX, 77555, USA
| | - Robin Stephens
- Department of Microbiology and Immunology, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX, 77555, USA. .,Department of Internal Medicine, Division of Infectious Diseases, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX, 77555-0435, USA. .,Institute for Human Infections and Immunity, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX, 77555, USA.
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42
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Plewes K, Turner GD, Dondorp AM. Pathophysiology, clinical presentation, and treatment of coma and acute kidney injury complicating falciparum malaria. Curr Opin Infect Dis 2018; 31:69-77. [PMID: 29206655 PMCID: PMC5768231 DOI: 10.1097/qco.0000000000000419] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
PURPOSE OF REVIEW Cerebral impairment and acute kidney injury (AKI) are independent predictors of mortality in both adults and children with severe falciparum malaria. In this review, we present recent advances in understanding the pathophysiology, clinical features, and management of these complications of severe malaria, and discuss future areas of research. RECENT FINDINGS Cerebral malaria and AKI are serious and well recognized complications of severe malaria. Common pathophysiological pathways include impaired microcirculation, due to sequestration of parasitized erythrocytes, systemic inflammatory responses, and endothelial activation. Recent MRI studies show significant brain swelling in both adults and children with evidence of posterior reversible encephalopathy syndrome-like syndrome although targeted interventions including mannitol and dexamethasone are not beneficial. Recent work shows association of cell-free hemoglobin oxidation stress involved in the pathophysiology of AKI in both adults and children. Paracetamol protected renal function likely by inhibiting cell-free-mediated oxidative stress. It is unclear if heme-mediated endothelial activation or oxidative stress is involved in cerebral malaria. SUMMARY The direct causes of cerebral and kidney dysfunction remain incompletely understood. Optimal treatment involves prompt diagnosis and effective antimalarial treatment with artesunate. Renal replacement therapy reduces mortality in AKI but delayed diagnosis is an issue.
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Affiliation(s)
- Katherine Plewes
- Faculty of Tropical Medicine, Mahidol Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand
- Division of Infectious Diseases, Department of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Gareth D.H. Turner
- Department of Cellular Pathology, John Radcliffe Hospital
- Nuffield Department of Clinical Medicine, Center for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
| | - Arjen M. Dondorp
- Faculty of Tropical Medicine, Mahidol Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand
- Nuffield Department of Clinical Medicine, Center for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
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43
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Kessler A, Dankwa S, Bernabeu M, Harawa V, Danziger SA, Duffy F, Kampondeni SD, Potchen MJ, Dambrauskas N, Vigdorovich V, Oliver BG, Hochman SE, Mowrey WB, MacCormick IJC, Mandala WL, Rogerson SJ, Sather DN, Aitchison JD, Taylor TE, Seydel KB, Smith JD, Kim K. Linking EPCR-Binding PfEMP1 to Brain Swelling in Pediatric Cerebral Malaria. Cell Host Microbe 2017; 22:601-614.e5. [PMID: 29107642 DOI: 10.1016/j.chom.2017.09.009] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Revised: 08/06/2017] [Accepted: 09/22/2017] [Indexed: 11/16/2022]
Abstract
Brain swelling is a major predictor of mortality in pediatric cerebral malaria (CM). However, the mechanisms leading to swelling remain poorly defined. Here, we combined neuroimaging, parasite transcript profiling, and laboratory blood profiles to develop machine-learning models of malarial retinopathy and brain swelling. We found that parasite var transcripts encoding endothelial protein C receptor (EPCR)-binding domains, in combination with high parasite biomass and low platelet levels, are strong indicators of CM cases with malarial retinopathy. Swelling cases presented low platelet levels and increased transcript abundance of parasite PfEMP1 DC8 and group A EPCR-binding domains. Remarkably, the dominant transcript in 50% of swelling cases encoded PfEMP1 group A CIDRα1.7 domains. Furthermore, a recombinant CIDRα1.7 domain from a pediatric CM brain autopsy inhibited the barrier-protective properties of EPCR in human brain endothelial cells in vitro. Together, these findings suggest a detrimental role for EPCR-binding CIDRα1 domains in brain swelling.
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Affiliation(s)
- Anne Kessler
- Department of Medicine, Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, NY 10461, USA
| | - Selasi Dankwa
- Center for Infectious Disease Research, Seattle, WA 98109, USA
| | - Maria Bernabeu
- Center for Infectious Disease Research, Seattle, WA 98109, USA
| | - Visopo Harawa
- Malawi-Liverpool Wellcome Trust Clinical Research Programme, Blantyre BT3, Malawi; University of Malawi, College of Medicine, Biomedical Department, Blantyre BT3, Malawi
| | | | - Fergal Duffy
- Center for Infectious Disease Research, Seattle, WA 98109, USA
| | | | - Michael J Potchen
- Department of Imaging Sciences, University of Rochester, Rochester, NY 14642, USA
| | | | | | - Brian G Oliver
- Center for Infectious Disease Research, Seattle, WA 98109, USA
| | - Sarah E Hochman
- Department of Medicine, New York University Langone Health, New York, NY 10016, USA
| | - Wenzhu B Mowrey
- Department of Medicine, Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, NY 10461, USA
| | - Ian J C MacCormick
- Malawi-Liverpool Wellcome Trust Clinical Research Programme, Blantyre BT3, Malawi; Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh EH16 4SB, UK; Department of Eye and Vision Sciences, University of Liverpool, Liverpool L69 3BX, UK
| | - Wilson L Mandala
- Malawi-Liverpool Wellcome Trust Clinical Research Programme, Blantyre BT3, Malawi; University of Malawi, College of Medicine, Biomedical Department, Blantyre BT3, Malawi; Academy of Medical Sciences, Malawi University of Science and Technology, Thyolo BT3, Malawi
| | - Stephen J Rogerson
- Department of Medicine at the Doherty Institute, The University of Melbourne, Melbourne, VIC 3000, Australia
| | - D Noah Sather
- Center for Infectious Disease Research, Seattle, WA 98109, USA
| | | | - Terrie E Taylor
- Blantyre Malaria Project, Blantyre BT3, Malawi; Department of Osteopathic Medical Specialities, College of Osteopathic Medicine, Michigan State University, East Lansing, MI 48824, USA
| | - Karl B Seydel
- Blantyre Malaria Project, Blantyre BT3, Malawi; Department of Osteopathic Medical Specialities, College of Osteopathic Medicine, Michigan State University, East Lansing, MI 48824, USA.
| | - Joseph D Smith
- Center for Infectious Disease Research, Seattle, WA 98109, USA; Department of Global Health, University of Washington, Seattle, WA 98195, USA.
| | - Kami Kim
- Department of Medicine, Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, NY 10461, USA.
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44
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Madaline TF, Hochman SE, Seydel KB, Liomba A, Saidi A, Matebule G, Mowrey WB, O'Hare B, Milner DA, Kim K. Rapid Diagnostic Testing of Hospitalized Malawian Children Reveals Opportunities for Improved HIV Diagnosis and Treatment. Am J Trop Med Hyg 2017; 97:1929-1935. [PMID: 29141709 DOI: 10.4269/ajtmh.17-0067] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Recent World Health Organization (WHO) guidelines recommend antiretroviral therapy (ART) for all HIV-infected people; previously CD4+ T lymphocyte quantification (CD4 count) or clinical staging determined eligibility for children ≥ 5 years old in low- and middle-income countries. We examined positive predictive value (PPV) of a rapid diagnostic test (RDT) algorithm and ART eligibility for hospitalized children with newly diagnosed HIV infection. We enrolled 363 hospitalized Malawian children age 2 months to 16 years with two serial positive HIV RDT from 2013 to 2015. Children aged ≤ 18 months whose nucleic acid testing was negative or unavailable were later excluded from the analysis (N = 16). If RNA PCR was undetectable, human immunodeficiency virus (HIV) enzyme immunoassay (EIA) and western blot (WB) were performed. Those with negative or discordant EIA and WB were considered HIV negative and excluded from further analysis (N = 6). ART eligibility was assessed using age, CD4 count, and clinical HIV stage. Among 150 patients with HIV RNA PCR results, 15 had undetectable HIV RNA. Of those, EIA and WB were positive in nine patients and negative or discordant in six patients. PPV of serial RDT was 90% versus RNA PCR alone and 96% versus combined RNA PCR, EIA, and WB. Of all patients aged ≥ 5 years, 8.9% were ineligible for ART under previous WHO guidelines. Improved HIV testing algorithms are needed for accurate diagnosis of HIV infection in children as prevalence of pediatric HIV declines. Universal treatment will significantly increase the numbers of older children who qualify for ART.
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Affiliation(s)
- Theresa F Madaline
- Department of Medicine, Montefiore Medical Center and Albert Einstein College of Medicine, Bronx, New York
| | - Sarah E Hochman
- Department of Medicine, New York University Langone Medical Center and New York University School of Medicine, New York, New York
| | - Karl B Seydel
- Blantyre Malaria Project, University of Malawi College of Medicine, Blantyre, Malawi.,Department of Osteopathic Medical Specialties, Michigan State University College of Osteopathic Medicine, East Lansing, Michigan
| | - Alice Liomba
- Department of Paediatrics and Child Health, University of Malawi College of Medicine, Blantyre, Malawi.,Blantyre Malaria Project, University of Malawi College of Medicine, Blantyre, Malawi
| | - Alex Saidi
- Department of Paediatrics and Child Health, University of Malawi College of Medicine, Blantyre, Malawi.,Blantyre Malaria Project, University of Malawi College of Medicine, Blantyre, Malawi
| | - Grace Matebule
- Department of Paediatrics and Child Health, University of Malawi College of Medicine, Blantyre, Malawi
| | - Wenzhu B Mowrey
- Department of Epidemiology & Population Health, Montefiore Medical Center and Albert Einstein College of Medicine, Bronx, New York
| | - Bernadette O'Hare
- Global Health Implementation, University of St. Andrews School of Medicine, North Haugh, United Kingdom.,Department of Paediatrics and Child Health, University of Malawi College of Medicine, Blantyre, Malawi
| | - Danny A Milner
- American Society for Clinical Pathology, Chicago, Illinois
| | - Kami Kim
- Departments of Pathology and Microbiology and Immunology, Montefiore Medical Center and Albert Einstein College of Medicine, Bronx, New York.,Department of Medicine, Montefiore Medical Center and Albert Einstein College of Medicine, Bronx, New York
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45
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J Joyner C, Consortium TM, Wood JS, Moreno A, Garcia A, Galinski MR. Case Report: Severe and Complicated Cynomolgi Malaria in a Rhesus Macaque Resulted in Similar Histopathological Changes as Those Seen in Human Malaria. Am J Trop Med Hyg 2017; 97:548-555. [PMID: 28829738 DOI: 10.4269/ajtmh.16-0742] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Histopathological data collected from patients with severe malaria have been instrumental for studying malaria pathogenesis. Animal models of malaria are critical to complement such studies. Here, the histopathological changes observed in a rhesus macaque with severe and complicated Plasmodium cynomolgi malaria are reported. The animal presented with thrombocytopenia, severe anemia, and hyperparasitemia during the acute infection. The macaque was given subcurative antimalarial treatment, fluid support, and a blood transfusion to treat the clinical complications, but at the time of transfusion, kidney function was compromised. These interventions did not restore kidney function, and the animal was euthanized due to irreversible renal failure. Gross pathological and histological examinations revealed that the lungs, kidneys, liver, spleen, and bone marrow exhibited abnormalities similar to those described in patients with malaria. Overall, this case report illustrates the similarities in the pathophysiological complications that can occur in human malaria and cynomolgi malaria in rhesus macaques.
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Affiliation(s)
- Chester J Joyner
- Malaria Host-Pathogen Interaction Center, Emory Vaccine Center, Yerkes National Primate Research Center, Emory University, Atlanta, Georgia
| | - The MaHPIC Consortium
- Malaria Host-Pathogen Interaction Center, Emory Vaccine Center, Yerkes National Primate Research Center, Emory University, Atlanta, Georgia
| | - Jennifer S Wood
- Division of Animal Resources, Yerkes National Primate Research Center, Emory University, Atlanta, Georgia
| | - Alberto Moreno
- Division of Infectious Diseases, Department of Medicine, Emory University, Atlanta, Georgia.,Emory Vaccine Center, Yerkes National Primate Research Center, Emory University, Atlanta, Georgia.,Malaria Host-Pathogen Interaction Center, Emory Vaccine Center, Yerkes National Primate Research Center, Emory University, Atlanta, Georgia
| | - Anapatricia Garcia
- Division of Pathology, Yerkes National Primate Research Center, Emory University, Atlanta, Georgia
| | - Mary R Galinski
- Malaria Host-Pathogen Interaction Center, Emory Vaccine Center, Yerkes National Primate Research Center, Emory University, Atlanta, Georgia.,Emory Vaccine Center, Yerkes National Primate Research Center, Emory University, Atlanta, Georgia.,Division of Infectious Diseases, Department of Medicine, Emory University, Atlanta, Georgia
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46
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Aetiology and Outcomes of Suspected Infections of the Central Nervous System in Children in Mbarara, Uganda. Sci Rep 2017; 7:2728. [PMID: 28578421 PMCID: PMC5457409 DOI: 10.1038/s41598-017-02741-w] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Accepted: 04/19/2017] [Indexed: 11/24/2022] Open
Abstract
Infections of the central nervous system (CNS) are severe conditions, leading to neurological sequelae or death. Knowledge of the causative agents is essential to develop guidelines for case management in resource-limited settings. Between August 2009 and October 2012, we conducted a prospective descriptive study of the aetiology of suspected CNS infections in children two months to 12 years old, with fever and at least one sign of CNS involvement in Mbarara Hospital, Uganda. Children were clinically evaluated on admission and discharge, and followed-up for 6 months for neurological sequelae. Pathogens were identified from cerebrospinal fluid (CSF) and blood using microbiological and molecular methods. We enrolled 459 children. Plasmodium falciparum (36.2%) and bacteria in CSF (13.3%) or blood (3.3%) were the most detected pathogens. Viruses were found in 27 (5.9%) children. No pathogen was isolated in 207 (45.1%) children. Patterns varied by age and HIV status. Eighty-three (18.1%) children died during hospitalisation, and 23 (5.0%) during follow-up. Forty-one (13.5%) children had neurological sequelae at the last visit. While malaria remains the main aetiology in children with suspected CNS infections, no pathogen was isolated in many children. The high mortality and high rate of neurological sequelae highlight the need for efficient diagnosis.
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47
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Shabani E, Ouma BJ, Idro R, Bangirana P, Opoka RO, Park GS, Conroy AL, John CC. Elevated cerebrospinal fluid tumour necrosis factor is associated with acute and long-term neurocognitive impairment in cerebral malaria. Parasite Immunol 2017; 39. [PMID: 28453871 DOI: 10.1111/pim.12438] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2017] [Accepted: 04/24/2017] [Indexed: 12/25/2022]
Abstract
Systemic tumour necrosis factor-α (TNF-α) may contribute to the pathogenesis of cerebral malaria (CM) by promoting endothelial activation and parasite sequestration. However, less is known about the role of central nervous system (CNS) TNF-α in CM. We assessed plasma (n=249) and cerebrospinal fluid (CSF) (n=167) TNF-α levels in Ugandan children with CM, plasma TNF-α in Ugandan community control children (n=198) and CSF TNF-α in North American control children who had recovered from leukaemia (n=13). Plasma and CSF TNF-α were measured by magnetic bead assay. We compared plasma and CSF TNF-α levels in children with CM to mortality, acute and chronic neurologic deficits and long-term neurocognitive impairment. Plasma and CSF TNF-α levels were higher in CM than control children (P<.0001 for both). CSF TNF-α levels were higher in children who had neurologic deficits at discharge or 6-month follow-up (P≤.05 for both). Elevated CSF but not plasma TNF-α was associated with longer coma duration (Spearman's rho .18, P=.02) and deficits in overall cognition in children 5 years and older (β coefficient -.74, 95% CI -1.35 to -0.13, P=.02). The study findings suggest that CNS TNF-α may be involved in the development of acute and chronic neurologic and cognitive sequelae in children with CM.
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Affiliation(s)
- E Shabani
- Department of Pediatrics, Division of Global Pediatrics, University of Minnesota, Minneapolis, MN, USA.,Ryan White Center for Pediatric Infectious Disease and Global Health, Department of Pediatrics, Indiana University, Indianapolis, IN, USA
| | - B J Ouma
- Department of Microbiology, Makerere University, Kampala, Uganda
| | - R Idro
- Department of Pediatrics and Child Health, Makerere University, Kampala, Uganda
| | - P Bangirana
- Department of Psychiatry, Makerere University, Kampala, Uganda
| | - R O Opoka
- Department of Pediatrics and Child Health, Makerere University, Kampala, Uganda
| | - G S Park
- Department of Medicine, University of Minnesota Medical School, Minneapolis, MN, USA
| | - A L Conroy
- Ryan White Center for Pediatric Infectious Disease and Global Health, Department of Pediatrics, Indiana University, Indianapolis, IN, USA
| | - C C John
- Department of Pediatrics, Division of Global Pediatrics, University of Minnesota, Minneapolis, MN, USA.,Ryan White Center for Pediatric Infectious Disease and Global Health, Department of Pediatrics, Indiana University, Indianapolis, IN, USA
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48
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Gillrie MR, Ho M. Dynamic interactions of Plasmodium spp. with vascular endothelium. Tissue Barriers 2017; 5:e1268667. [PMID: 28452684 PMCID: PMC5362994 DOI: 10.1080/21688370.2016.1268667] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Revised: 11/24/2016] [Accepted: 11/30/2016] [Indexed: 12/18/2022] Open
Abstract
Plasmodial species are protozoan parasites that infect erythrocytes. As such, they are in close contact with microvascular endothelium for most of the life cycle in the mammalian host. The host-parasite interactions of this stage of the infection are responsible for the clinical manifestations of the disease that range from a mild febrile illness to severe and frequently fatal syndromes such as cerebral malaria and multi-organ failure. Plasmodium falciparum, the causative agent of the most severe form of malaria, is particularly predisposed to modulating endothelial function through either direct adhesion to endothelial receptor molecules, or by releasing potent host and parasite products that can stimulate endothelial activation and/or disrupt barrier function. In this review, we provide a critical analysis of the current clinical and laboratory evidence for endothelial dysfunction during severe P. falciparum malaria. Future investigations using state-of-the-art technologies such as mass cytometry and organs-on-chips to further delineate parasite-endothelial cell interactions are also discussed.
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Affiliation(s)
- Mark R. Gillrie
- Department of Microbiology, Immunology and Infectious Diseases, University of Calgary, Calgary, Alberta, Canada
- Department of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - May Ho
- Department of Microbiology, Immunology and Infectious Diseases, University of Calgary, Calgary, Alberta, Canada
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49
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Bernabeu M, Smith JD. EPCR and Malaria Severity: The Center of a Perfect Storm. Trends Parasitol 2016; 33:295-308. [PMID: 27939609 DOI: 10.1016/j.pt.2016.11.004] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Revised: 11/07/2016] [Accepted: 11/10/2016] [Indexed: 12/20/2022]
Abstract
Severe malaria due to Plasmodium falciparum infection causes nearly half a million deaths per year. The different symptomatology and disease manifestations among patients have hampered understanding of severe malaria pathology and complicated efforts to develop targeted disease interventions. Infected erythrocyte sequestration in the microvasculature plays a critical role in the development of severe disease, and there is increasing evidence that cytoadherent parasites interact with host factors to enhance the damage caused by the parasite. The recent discovery that parasite binding to endothelial protein C receptor (EPCR) is associated with severe disease has suggested new mechanisms of pathology and provided new avenues for severe malaria adjunctive therapy research.
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Affiliation(s)
- Maria Bernabeu
- Center for Infectious Disease Research, Seattle, WA 98109, USA
| | - Joseph D Smith
- Center for Infectious Disease Research, Seattle, WA 98109, USA; Department of Global Health, University of Washington, Seattle, WA 98195, USA.
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50
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Brand NR, Opoka RO, Hamre KES, John CC. Differing Causes of Lactic Acidosis and Deep Breathing in Cerebral Malaria and Severe Malarial Anemia May Explain Differences in Acidosis-Related Mortality. PLoS One 2016; 11:e0163728. [PMID: 27684745 PMCID: PMC5042445 DOI: 10.1371/journal.pone.0163728] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2016] [Accepted: 09/13/2016] [Indexed: 12/04/2022] Open
Abstract
Lactic acidosis (LA) is a marker for mortality in severe malaria, but the mechanisms that lead to LA in the different types of severe malaria and the extent to which LA-associated mortality differs by type of severe malaria are not well described. We assessed the frequency of LA in children admitted to Mulago Hospital, Kampala, Uganda with cerebral malaria (CM, n = 193) or severe malarial anemia (SMA, n = 216). LA was compared to mortality and measures of parasite biomass and sequestration (P. falciparum histidine-rich protein-2 (PfHRP2) concentration, platelet count), and to a measure of systemic tissue oxygen delivery (hemoglobin level). LA was more frequent in children with SMA than CM (SMA, 47.7%, CM, 34.2%, P = 0.006), but mortality was higher in children with CM (13.0%) than SMA (0.5%, P<0.0001). In CM, LA was associated with increased PfHRP2 concentration and decreased platelet count but was not associated with hemoglobin level. In contrast, in SMA, LA was associated with a decreased hemoglobin level, but was not associated with PfHRP2 concentration or platelet count. LA was related to mortality only in CM. In multivariable regression analysis of the effect PfHRP2 and hemoglobin levels on LA and DB, only PfHRP2 level increased risk of LA and DB in CM, while in SMA, elevated hemoglobin strongly decreased risk of LA and DB, and PfHRP2 level modestly increased risk of LA. The study findings suggest that LA in CM is due primarily to parasite sequestration, which currently has no effective adjunctive therapy, while LA in SMA is due primarily to anemia, which is rapidly corrected with blood transfusion. Differing etiologies of LA in CM and SMA may explain why LA is associated with mortality in CM but not SMA.
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Affiliation(s)
- Nathan R. Brand
- Columbia University College of Physicians and Surgeons, School of Medicine, New York, New York, United States of America
| | - Robert O. Opoka
- Makerere University, Department of Pediatrics, Kampala, Uganda
| | - Karen E. S. Hamre
- University of Minnesota, Department of Pediatrics, Minneapolis, Minnesota, United States of America
| | - Chandy C. John
- Indiana University, Department of Pediatrics, Indianapolis, Indiana, United States of America
- * E-mail:
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