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Zhou Y, Leahy K, Grose A, Lykins J, Siddiqui M, Leong N, Goodall P, Withers S, Ashi K, Schrantz S, Tesic V, Abeleda AP, Beavis K, Clouser F, Ismail M, Christmas M, Piarroux R, Limonne D, Chapey E, Abraham S, Baird I, Thibodeau J, Boyer KM, Torres E, Conrey S, Wang K, Staat MA, Back N, L’Ollivier C, Mahinc C, Flori P, Gomez-Marin J, Peyron F, Houzé S, Wallon M, McLeod R. Novel paradigm enables accurate monthly gestational screening to prevent congenital toxoplasmosis and more. PLoS Negl Trop Dis 2024; 18:e0011335. [PMID: 38805559 PMCID: PMC11132520 DOI: 10.1371/journal.pntd.0011335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 04/01/2024] [Indexed: 05/30/2024] Open
Abstract
BACKGROUND Congenital toxoplasmosis is a treatable, preventable disease, but untreated causes death, prematurity, loss of sight, cognition and motor function, and substantial costs worldwide. OBJECTIVES We asked whether high performance of an Immunochromatographic-test (ICT) could enable accurate, rapid diagnosis/treatment, establishing new, improved care-paradigms at point-of-care and clinical laboratory. METHODS Data were obtained in 12 studies/analyses addressing: 1-feasibility/efficacy; 2-false-positives; 3-acceptability; 4-pink/black-line/all studies; 5-time/cost; 6-Quick-Information/Limit-of-detection; 7, 8-acute;-chronic; 9-epidemiology; 10-ADBio; 11,12-Commentary/Cases/Chronology. FINDINGS ICT was compared with gold-standard or predicate-tests. Overall, ICT performance for 1093 blood/4967 sera was 99.2%/97.5% sensitive and 99.0%/99.7% specific. However, in clinical trial, FDA-cleared-predicate tests initially caused practical, costly problems due to false-positive-IgM results. For 58 persons, 3/43 seronegative and 2/15 chronically infected persons had false positive IgM predicate tests. This caused substantial anxiety, concerns, and required costly, delayed confirmation in reference centers. Absence of false positive ICT results contributes to solutions: Lyon and Paris France and USA Reference laboratories frequently receive sera with erroneously positive local laboratory IgM results impeding patient care. Therefore, thirty-two such sera referred to Lyon's Reference laboratory were ICT-tested. We collated these with other earlier/ongoing results: 132 of 137 USA or French persons had false-positive local laboratory IgM results identified correctly as negative by ICT. Five false positive ICT results in Tunisia and Marseille, France, emphasize need to confirm positive ICT results with Sabin-Feldman-Dye-test or western blot. Separate studies demonstrated high performance in detecting acute infections, meeting FDA, CLIA, WHO REASSURED, CEMark criteria and patient and physician satisfaction with monthly-gestational-ICT-screening. CONCLUSIONS/SIGNIFICANCE This novel paradigm using ICT identifies likely false positives or raises suspicion that a result is truly positive, rapidly needing prompt follow up and treatment. Thus, ICT enables well-accepted gestational screening programs that facilitate rapid treatment saving lives, sight, cognition and motor function. This reduces anxiety, delays, work, and cost at point-of-care and clinical laboratories. TRIAL REGISTRATION NCT04474132, https://clinicaltrials.gov/study/NCT04474132 ClinicalTrials.gov.
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Affiliation(s)
- Ying Zhou
- Departments of Ophthalmology and Visual Science, The University of Chicago, Chicago, Illinois, United States of America
| | - Karen Leahy
- Department of Obstetrics and Gynecology, The University of Chicago, Chicago, Illinois, United States of America
| | - Andrew Grose
- Departments of Ophthalmology and Visual Science, The University of Chicago, Chicago, Illinois, United States of America
- Pritzker School of Medicine, Division of Infectious Diseases, The University of Chicago, Chicago, Illinois, United States of America
| | - Joseph Lykins
- Departments of Ophthalmology and Visual Science, The University of Chicago, Chicago, Illinois, United States of America
- Pritzker School of Medicine, Division of Infectious Diseases, The University of Chicago, Chicago, Illinois, United States of America
| | - Maryam Siddiqui
- Department of Obstetrics and Gynecology, The University of Chicago, Chicago, Illinois, United States of America
| | - Nicole Leong
- Department of Obstetrics and Gynecology, The University of Chicago, Chicago, Illinois, United States of America
| | - Perpetua Goodall
- Department of Obstetrics and Gynecology, The University of Chicago, Chicago, Illinois, United States of America
| | - Shawn Withers
- Departments of Ophthalmology and Visual Science, The University of Chicago, Chicago, Illinois, United States of America
| | - Kevin Ashi
- Departments of Ophthalmology and Visual Science, The University of Chicago, Chicago, Illinois, United States of America
- Pritzker School of Medicine, Division of Infectious Diseases, The University of Chicago, Chicago, Illinois, United States of America
| | - Stephen Schrantz
- Pritzker School of Medicine, Division of Infectious Diseases, The University of Chicago, Chicago, Illinois, United States of America
- Chicago Medicine, The University of Chicago, Chicago, Illinois, United States of America
- Department of Pediatrics, Division of Infectious Diseases, The University of Chicago, Chicago, Illinois, United States of America
- Department of Medicine, The University of Chicago, Chicago, Illinois, United States of America
| | - Vera Tesic
- Pritzker School of Medicine, Division of Infectious Diseases, The University of Chicago, Chicago, Illinois, United States of America
- Chicago Medicine, The University of Chicago, Chicago, Illinois, United States of America
- Department of Pathology, The University of Chicago, Chicago, Illinois, United States of America
| | - Ana Precy Abeleda
- Chicago Medicine, The University of Chicago, Chicago, Illinois, United States of America
- Department of Pathology, The University of Chicago, Chicago, Illinois, United States of America
| | - Kathleen Beavis
- Pritzker School of Medicine, Division of Infectious Diseases, The University of Chicago, Chicago, Illinois, United States of America
- Chicago Medicine, The University of Chicago, Chicago, Illinois, United States of America
- Department of Pathology, The University of Chicago, Chicago, Illinois, United States of America
| | - Fatima Clouser
- Departments of Ophthalmology and Visual Science, The University of Chicago, Chicago, Illinois, United States of America
| | - Mahmoud Ismail
- Department of Obstetrics and Gynecology, The University of Chicago, Chicago, Illinois, United States of America
- Pritzker School of Medicine, Division of Infectious Diseases, The University of Chicago, Chicago, Illinois, United States of America
- Chicago Medicine, The University of Chicago, Chicago, Illinois, United States of America
| | - Monica Christmas
- Department of Obstetrics and Gynecology, The University of Chicago, Chicago, Illinois, United States of America
- Pritzker School of Medicine, Division of Infectious Diseases, The University of Chicago, Chicago, Illinois, United States of America
- Chicago Medicine, The University of Chicago, Chicago, Illinois, United States of America
| | | | | | - Emmanuelle Chapey
- Institut des agents infectieux, Hôpital de la Croix-Rousse, Lyon, France
| | - Sylvie Abraham
- Laboratory of Parasitologie, Bichat-Claude Bernard Hôpital, Paris, France
| | - Isabelle Baird
- The College, The University of Chicago, Chicago, Illinois, United States of America
- Global Health Center, The University of Chicago, Chicago, Illinois, United States of America
| | - Juliette Thibodeau
- The College, The University of Chicago, Chicago, Illinois, United States of America
- Global Health Center, The University of Chicago, Chicago, Illinois, United States of America
| | - Kenneth M. Boyer
- Department of Pediatrics, Division of Infectious Diseases, Rush Presbyterian Hospital and Medical Center, Chicago, Illinois, United States of America
| | - Elizabeth Torres
- Group of Molecular Parasitology (GEPAMOL), Center of Biomedical Research, Faculty of Health Sciences, University of Quindio, Armenia (Quindio), Colombia
| | - Shannon Conrey
- University of Cincinnati and Cincinnati Children’s Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio, United States of America
| | - Kanix Wang
- Carl H. Lindner College of Business, The University of Cincinnati, Cincinnati, Ohio, United States of America
| | - Mary Allen Staat
- University of Cincinnati and Cincinnati Children’s Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio, United States of America
| | - Nancy Back
- University of Cincinnati and Cincinnati Children’s Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio, United States of America
| | - Coralie L’Ollivier
- Centre National de Référence Toxoplasmose—Pôle Sérologie, Hôpitaux Universitaires de Strasbourg, Strasbourg, France
- IHU-Méditerranée Infection, Assistance Publique Hôpitaux de Marseille (AP-HM), Marseille, France; Aix Marseille University, IRD, AP-HM, SSA, VITROME, IHU Méditerranée, Marseille, France
| | - Caroline Mahinc
- Parasitology and Mycology Laboratory, Pôle de Biologie-Pathologie, University Hospital of Saint Etienne, Saint Etienne, France
| | - Pierre Flori
- Parasitology and Mycology Laboratory, Pôle de Biologie-Pathologie, University Hospital of Saint Etienne, Saint Etienne, France
| | - Jorge Gomez-Marin
- Group of Molecular Parasitology (GEPAMOL), Center of Biomedical Research, Faculty of Health Sciences, University of Quindio, Armenia (Quindio), Colombia
| | - Francois Peyron
- Institut des agents infectieux, Hôpital de la Croix-Rousse, Lyon, France
| | - Sandrine Houzé
- Laboratory of Parasitologie, Bichat-Claude Bernard Hôpital, Paris, France
| | - Martine Wallon
- Institut des agents infectieux, Hôpital de la Croix-Rousse, Lyon, France
| | - Rima McLeod
- Departments of Ophthalmology and Visual Science, The University of Chicago, Chicago, Illinois, United States of America
- Pritzker School of Medicine, Division of Infectious Diseases, The University of Chicago, Chicago, Illinois, United States of America
- Department of Pediatrics, Division of Infectious Diseases, The University of Chicago, Chicago, Illinois, United States of America
- Department of Medicine, The University of Chicago, Chicago, Illinois, United States of America
- The College, The University of Chicago, Chicago, Illinois, United States of America
- Global Health Center, The University of Chicago, Chicago, Illinois, United States of America
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Rodriguez JB, Szajnman SH. An updated review of chemical compounds with anti-Toxoplasma gondii activity. Eur J Med Chem 2023; 262:115885. [PMID: 37871407 DOI: 10.1016/j.ejmech.2023.115885] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 09/30/2023] [Accepted: 10/15/2023] [Indexed: 10/25/2023]
Abstract
The opportunistic apicomplexan parasite Toxoplasma gondii is the etiologic agent for toxoplasmosis, which can infect a widespread range of hosts, particularly humans and warm-blooded animals. The present chemotherapy to treat or prevent toxoplasmosis is deficient and is based on diverse drugs such as atovaquone, trimethoprim, spiramycine, which are effective in acute toxoplasmosis. Therefore, a safe chemotherapy is required for toxoplasmosis considering that its responsible agent, T. gondii, provokes severe illness and death in pregnant women and immunodeficient patients. A certain disadvantage of the available treatments is the lack of effectiveness against the tissue cyst of the parasite. A safe chemotherapy to combat toxoplasmosis should be based on the metabolic differences between the parasite and the mammalian host. This article covers different relevant molecular targets to combat this disease including the isoprenoid pathway (farnesyl diphosphate synthase, squalene synthase), dihydrofolate reductase, calcium-dependent protein kinases, histone deacetylase, mitochondrial electron transport chain, etc.
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Affiliation(s)
- Juan B Rodriguez
- Departamento de Química Orgánica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellón 2, C1428EHA, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires, Unidad de Microanálisis y Métodos Físicos en Química Orgánica (UMYMFOR), C1428EHA, Buenos Aires, Argentina.
| | - Sergio H Szajnman
- Departamento de Química Orgánica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellón 2, C1428EHA, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires, Unidad de Microanálisis y Métodos Físicos en Química Orgánica (UMYMFOR), C1428EHA, Buenos Aires, Argentina
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Murphy RD, Troublefield CA, Miracle JS, Young LEA, Brizzee CO, Dhara A, Sun RC, Vander Kooi CW, Gentry MS, Sinai AP. TgLaforin, a glucan phosphatase, reveals the dynamic role of storage polysaccharides in Toxoplasma gondii tachyzoites and bradyzoites. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.29.560185. [PMID: 37808860 PMCID: PMC10557770 DOI: 10.1101/2023.09.29.560185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/10/2023]
Abstract
The asexual stages of Toxoplasma gondii are defined by the rapidly growing tachyzoite during the acute infection and by the slow growing bradyzoite housed within tissue cysts during the chronic infection. These stages represent unique physiological states, each with distinct glucans reflecting differing metabolic needs. A defining feature of T. gondii bradyzoites is the presence of insoluble storage glucans known as amylopectin granules (AGs) that are believed to play a role in reactivation, but their functions during the chronic infection remain largely unexplored. More recently, the presence of storage glucans has been recognized in tachyzoites where their precise function and architecture have yet to be fully defined. Importantly, the T. gondii genome encodes activities needed for glucan turnover: a glucan phosphatase (TgLaforin; TGME49_205290) and a glucan kinase (TgGWD; TGME49_214260) that catalyze a cycle of reversible glucan phosphorylation required for glucan degradation by amylases. The expression of these enzymes in tachyzoites supports the existence of a storage glucan, evidence that is corroborated by specific labeling with the anti-glycogen antibody IV58B6. Disruption of reversible glucan phosphorylation via a CRISPR/Cas9 knockout (KO) of TgLaforin revealed no growth defects under nutrient-replete conditions in tachyzoites. However, the growth of TgLaforin-KO tachyzoites was severely stunted when starved of glutamine, even under glucose replete conditions. The loss of TgLaforin also resulted in the attenuation of acute virulence in mice accompanied by a lower cyst burden. Defective cyst formation due to profound changes in AG morphology was also observed in TgLaforin-KO parasites, both in vitro and in vivo. Together, these data demonstrate the importance of glucan turnover across the T. gondii asexual cycle. These findings, alongside our previously identified class of small molecules that inhibit TgLaforin, implicate reversible glucan phosphorylation as a legitimate target for the development of new drugs against chronic T. gondii infections.
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Affiliation(s)
- Robert D Murphy
- Department of Microbiology, Immunology, and Molecular Genetics, College of Medicine, University of Kentucky
- Department of Molecular and Cellular Biochemistry, College of Medicine, University of Kentucky
| | - Cortni A Troublefield
- Department of Microbiology, Immunology, and Molecular Genetics, College of Medicine, University of Kentucky
| | - Joy S Miracle
- Department of Microbiology, Immunology, and Molecular Genetics, College of Medicine, University of Kentucky
| | - Lyndsay E A Young
- Department of Molecular and Cellular Biochemistry, College of Medicine, University of Kentucky
| | - Corey O Brizzee
- Department of Molecular and Cellular Biochemistry, College of Medicine, University of Kentucky
| | - Animesh Dhara
- Department of Microbiology, Immunology, and Molecular Genetics, College of Medicine, University of Kentucky
| | - Ramon C Sun
- Department of Molecular and Cellular Biochemistry, College of Medicine, University of Kentucky
| | - Craig W Vander Kooi
- Department of Molecular and Cellular Biochemistry, College of Medicine, University of Kentucky
| | - Matthew S Gentry
- Department of Molecular and Cellular Biochemistry, College of Medicine, University of Kentucky
| | - Anthony P Sinai
- Department of Molecular and Cellular Biochemistry, College of Medicine, University of Kentucky
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Esser L, Zhou F, Zeher A, Wu W, Huang R, Yu CA, Lane KD, Wellems TE, Xia D. Structure of complex III with bound antimalarial agent CK-2-68 provides insights into selective inhibition of Plasmodium cytochrome bc 1 complexes. J Biol Chem 2023; 299:104860. [PMID: 37236355 PMCID: PMC10404626 DOI: 10.1016/j.jbc.2023.104860] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 05/17/2023] [Accepted: 05/18/2023] [Indexed: 05/28/2023] Open
Abstract
Among the various components of the protozoan Plasmodium mitochondrial respiratory chain, only Complex III is a validated cellular target for antimalarial drugs. The compound CK-2-68 was developed to specifically target the alternate NADH dehydrogenase of the malaria parasite respiratory chain, but the true target for its antimalarial activity has been controversial. Here, we report the cryo-EM structure of mammalian mitochondrial Complex III bound with CK-2-68 and examine the structure-function relationships of the inhibitor's selective action on Plasmodium. We show that CK-2-68 binds specifically to the quinol oxidation site of Complex III, arresting the motion of the iron-sulfur protein subunit, which suggests an inhibition mechanism similar to that of Pf-type Complex III inhibitors such as atovaquone, stigmatellin, and UHDBT. Our results shed light on the mechanisms of observed resistance conferred by mutations, elucidate the molecular basis of the wide therapeutic window of CK-2-68 for selective action of Plasmodium vs. host cytochrome bc1, and provide guidance for future development of antimalarials targeting Complex III.
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Affiliation(s)
- Lothar Esser
- Laboratory of Cell Biology, Center for Cancer Research National Cancer Institute, NIH, Bethesda, Maryland, USA
| | - Fei Zhou
- Laboratory of Cell Biology, Center for Cancer Research National Cancer Institute, NIH, Bethesda, Maryland, USA
| | - Allison Zeher
- Laboratory of Cell Biology, Center for Cancer Research National Cancer Institute, NIH, Bethesda, Maryland, USA; NIH Intramural Cryo-EM Consortium (NICE), Bethesda, Maryland, USA
| | - Weimin Wu
- Center for Molecular Microscopy, Center for Cancer Research, National Cancer Institute, NIH, Frederick, Maryland, USA
| | - Rick Huang
- Laboratory of Cell Biology, Center for Cancer Research National Cancer Institute, NIH, Bethesda, Maryland, USA; NIH Intramural Cryo-EM Consortium (NICE), Bethesda, Maryland, USA
| | - Chang-An Yu
- Department of Biochemistry, Oklahoma State University, Stillwater, Oklahoma, USA
| | - Kristin D Lane
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, Maryland, USA
| | - Thomas E Wellems
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, Maryland, USA
| | - Di Xia
- Laboratory of Cell Biology, Center for Cancer Research National Cancer Institute, NIH, Bethesda, Maryland, USA.
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Sleda MA, Li ZH, Behera R, Baierna B, Li C, Jumpathong J, Malwal SR, Kawamukai M, Oldfield E, Moreno SNJ. The Heptaprenyl Diphosphate Synthase (Coq1) Is the Target of a Lipophilic Bisphosphonate That Protects Mice against Toxoplasma gondii Infection. mBio 2022; 13:e0196622. [PMID: 36129297 PMCID: PMC9600589 DOI: 10.1128/mbio.01966-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Accepted: 08/15/2022] [Indexed: 11/20/2022] Open
Abstract
Prenyldiphosphate synthases catalyze the reaction of allylic diphosphates with one or more isopentenyl diphosphate molecules to form compounds such as farnesyl diphosphate, used in, e.g., sterol biosynthesis and protein prenylation, as well as longer "polyprenyl" diphosphates, used in ubiquinone and menaquinone biosynthesis. Quinones play an essential role in electron transport and are associated with the inner mitochondrial membrane due to the presence of the polyprenyl group. In this work, we investigated the synthesis of the polyprenyl diphosphate that alkylates the ubiquinone ring precursor in Toxoplasma gondii, an opportunistic pathogen that causes serious disease in immunocompromised patients and the unborn fetus. The enzyme that catalyzes this early step of the ubiquinone synthesis is Coq1 (TgCoq1), and we show that it produces the C35 species heptaprenyl diphosphate. TgCoq1 localizes to the mitochondrion and is essential for in vitro T. gondii growth. We demonstrate that the growth defect of a T. gondii TgCoq1 mutant is rescued by complementation with a homologous TgCoq1 gene or with a (C45) solanesyl diphosphate synthase from Trypanosoma cruzi (TcSPPS). We find that a lipophilic bisphosphonate (BPH-1218) inhibits T. gondii growth at low-nanomolar concentrations, while overexpression of the TgCoq1 enzyme dramatically reduced growth inhibition by the bisphosphonate. Both the severe growth defect of the mutant and the inhibition by BPH-1218 were rescued by supplementation with a long-chain (C30) ubiquinone (UQ6). Importantly, BPH-1218 also protected mice against a lethal T. gondii infection. TgCoq1 thus represents a potential drug target that could be exploited for improved chemotherapy of toxoplasmosis. IMPORTANCE Millions of people are infected with Toxoplasma gondii, and the available treatment for toxoplasmosis is not ideal. Most of the drugs currently used are only effective for the acute infection, and treatment can trigger serious side effects requiring changes in the therapeutic approach. There is, therefore, a compelling need for safe and effective treatments for toxoplasmosis. In this work, we characterize an enzyme of the mitochondrion of T. gondii that can be inhibited by an isoprenoid pathway inhibitor. We present evidence that demonstrates that inhibition of the enzyme is linked to parasite death. In addition, the inhibitor can protect mice against a lethal dose of T. gondii. Our results thus reveal a promising chemotherapeutic target for the development of new medicines for toxoplasmosis.
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Affiliation(s)
- Melissa A. Sleda
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA
- Department of Cellular Biology, University of Georgia, Athens, Georgia, USA
| | - Zhu-Hong Li
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA
| | - Ranjan Behera
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA
| | - Baihetiya Baierna
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA
- Department of Cellular Biology, University of Georgia, Athens, Georgia, USA
| | - Catherine Li
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA
| | - Jomkwan Jumpathong
- Department of Life Sciences, Faculty of Life and Environmental Sciences, Shimane University, Matsue, Japan
| | - Satish R. Malwal
- Department of Chemistry, University of Illinois at Urbana Champaign, Urbana, Illinois, USA
| | - Makoto Kawamukai
- Department of Life Sciences, Faculty of Life and Environmental Sciences, Shimane University, Matsue, Japan
| | - Eric Oldfield
- Department of Chemistry, University of Illinois at Urbana Champaign, Urbana, Illinois, USA
| | - Silvia N. J. Moreno
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA
- Department of Cellular Biology, University of Georgia, Athens, Georgia, USA
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Alday PH, Nilsen A, Doggett JS. Structure-activity relationships of Toxoplasma gondii cytochrome bc1 inhibitors. Expert Opin Drug Discov 2022; 17:997-1011. [PMID: 35772172 PMCID: PMC9561756 DOI: 10.1080/17460441.2022.2096588] [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: 04/18/2022] [Accepted: 06/28/2022] [Indexed: 11/04/2022]
Abstract
INTRODUCTION Toxoplasma gondii is a prolific apicomplexan parasite that infects human and nonhuman animals worldwide and can cause severe brain and eye disease. Safer, more effective therapies for toxoplasmosis are needed. Cytochrome bc1 inhibitors are remarkably effective against toxoplasmosis and other apicomplexan-caused diseases. AREAS COVERED This work reviews T. gondii cytochrome bc1 inhibitors. Emphasis is placed on the structure-activity relationships of these inhibitors with regard to efficacy, pharmacokinetics, selectivity of T. gondii cytochrome bc1 over host, safety, and potential therapeutic strategies. EXPERT OPINION Cytochrome bc1 inhibitors are highly promising compounds for toxoplasmosis that have been effective in clinical and preclinical studies. Clinical experience with atovaquone previously validated cytochrome bc1 as a tractable drug target and, over the past decade, optimization of cytochrome bc1 inhibitors has resulted in improved bioavailability, metabolic stability, potency, blood-brain barrier penetration, and selectivity for the T. gondii cytochrome bc1 over the mammalian bc1. Recent studies have demonstrated preclinical safety, identified novel therapeutic strategies for toxoplasmosis using synergistic combinations or long-acting administration and provided insight into their role in chronic infection. This research has identified drug candidates that are more effective than clinically used drugs in preclinical measures of efficacy.
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Affiliation(s)
- Phil Holland Alday
- Portland VA Medical Center, Portland, Oregon, USA
- Oregon Health & Science University, Portland, Oregon, USA
| | - Aaron Nilsen
- Portland VA Medical Center, Portland, Oregon, USA
- Oregon Health & Science University, Portland, Oregon, USA
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Abstract
Purpose of Review Review building of programs to eliminate Toxoplasma infections. Recent Findings
Morbidity and mortality from toxoplasmosis led to programs in USA, Panama, and Colombia to facilitate understanding, treatment, prevention, and regional resources, incorporating student work. Summary Studies foundational for building recent, regional approaches/programs are reviewed. Introduction provides an overview/review of programs in Panamá, the United States, and other countries. High prevalence/risk of exposure led to laws mandating testing in gestation, reporting, and development of broad-based teaching materials about Toxoplasma. These were tested for efficacy as learning tools for high-school students, pregnant women, medical students, physicians, scientists, public health officials and general public. Digitized, free, smart phone application effectively taught pregnant women about toxoplasmosis prevention. Perinatal infection care programs, identifying true regional risk factors, and point-of-care gestational screening facilitate prevention and care. When implemented fully across all demographics, such programs present opportunities to save lives, sight, and cognition with considerable spillover benefits for individuals and societies. Supplementary Information The online version contains supplementary material available at 10.1007/s40124-022-00269-w.
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Building Programs to Eradicate Toxoplasmosis Part IV: Understanding and Development of Public Health Strategies and Advances “Take a Village”. CURRENT PEDIATRICS REPORTS 2022; 10:125-154. [PMID: 35991908 PMCID: PMC9379243 DOI: 10.1007/s40124-022-00268-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/29/2022] [Indexed: 11/12/2022]
Abstract
Purpose of Review Review international efforts to build a global public health initiative focused on toxoplasmosis with spillover benefits to save lives, sight, cognition and motor function benefiting maternal and child health. Recent Findings Multiple countries’ efforts to eliminate toxoplasmosis demonstrate progress and context for this review and new work. Summary Problems with potential solutions proposed include accessibility of accurate, inexpensive diagnostic testing, pre-natal screening and facilitating tools, missed and delayed neonatal diagnosis, restricted access, high costs, delays in obtaining medicines emergently, delayed insurance pre-approvals and high medicare copays taking considerable physician time and effort, harmful shortcuts being taken in methods to prepare medicines in settings where access is restricted, reluctance to perform ventriculoperitoneal shunts promptly when needed without recognition of potential benefit, access to resources for care, especially for marginalized populations, and limited use of recent advances in management of neurologic and retinal disease which can lead to good outcomes. Supplementary Information The online version contains supplementary material available at 10.1007/s40124-022-00268-x.
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Amporndanai K, Pinthong N, O’Neill PM, Hong WD, Amewu RK, Pidathala C, Berry NG, Leung SC, Ward SA, Biagini GA, Hasnain SS, Antonyuk SV. Targeting the Ubiquinol-Reduction (Q i) Site of the Mitochondrial Cytochrome bc1 Complex for the Development of Next Generation Quinolone Antimalarials. BIOLOGY 2022; 11:biology11081109. [PMID: 35892964 PMCID: PMC9330653 DOI: 10.3390/biology11081109] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 07/11/2022] [Accepted: 07/18/2022] [Indexed: 11/16/2022]
Abstract
Antimalarials targeting the ubiquinol-oxidation (Qo) site of the Plasmodium falciparum bc1 complex, such as atovaquone, have become less effective due to the rapid emergence of resistance linked to point mutations in the Qo site. Recent findings showed a series of 2-aryl quinolones mediate inhibitions of this complex by binding to the ubiquinone-reduction (Qi) site, which offers a potential advantage in circumventing drug resistance. Since it is essential to understand how 2-aryl quinolone lead compounds bind within the Qi site, here we describe the co-crystallization and structure elucidation of the bovine cytochrome bc1 complex with three different antimalarial 4(1H)-quinolone sub-types, including two 2-aryl quinolone derivatives and a 3-aryl quinolone analogue for comparison. Currently, no structural information is available for Plasmodial cytochrome bc1. Our crystallographic studies have enabled comparison of an in-silico homology docking model of P. falciparum with the mammalian's equivalent, enabling an examination of how binding compares for the 2- versus 3-aryl analogues. Based on crystallographic and computational modeling, key differences in human and P. falciparum Qi sites have been mapped that provide new insights that can be exploited for the development of next-generation antimalarials with greater selective inhibitory activity against the parasite bc1 with improved antimalarial properties.
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Affiliation(s)
- Kangsa Amporndanai
- Molecular Biophysics Group, Institute of Systems, Molecular and Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Liverpool L69 7ZB, UK; (K.A.); (N.P.); (S.S.H.)
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232-0146, USA
| | - Nattapon Pinthong
- Molecular Biophysics Group, Institute of Systems, Molecular and Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Liverpool L69 7ZB, UK; (K.A.); (N.P.); (S.S.H.)
- Department of Protozoology, Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand
| | - Paul M. O’Neill
- Department of Chemistry, University of Liverpool, Liverpool L69 7ZD, UK; (W.D.H.); (R.K.A.); (C.P.); (N.G.B.); (S.C.L.)
- Correspondence: (P.M.O.); (S.V.A.); Tel.: +44-(0)-1517955145 (S.V.A.); +44-(0)-1517943552 (P.M.O.)
| | - W. David Hong
- Department of Chemistry, University of Liverpool, Liverpool L69 7ZD, UK; (W.D.H.); (R.K.A.); (C.P.); (N.G.B.); (S.C.L.)
| | - Richard K. Amewu
- Department of Chemistry, University of Liverpool, Liverpool L69 7ZD, UK; (W.D.H.); (R.K.A.); (C.P.); (N.G.B.); (S.C.L.)
- Department of Chemistry, School of Physical and Mathematical Sciences, University of Ghana, Accra P.O. Box LG 586, Ghana
| | - Chandrakala Pidathala
- Department of Chemistry, University of Liverpool, Liverpool L69 7ZD, UK; (W.D.H.); (R.K.A.); (C.P.); (N.G.B.); (S.C.L.)
- Composite Interceptive Med-Science Laboratories Pvt. Ltd., Bengaluru 60099, Karnataka, India
| | - Neil G. Berry
- Department of Chemistry, University of Liverpool, Liverpool L69 7ZD, UK; (W.D.H.); (R.K.A.); (C.P.); (N.G.B.); (S.C.L.)
| | - Suet C. Leung
- Department of Chemistry, University of Liverpool, Liverpool L69 7ZD, UK; (W.D.H.); (R.K.A.); (C.P.); (N.G.B.); (S.C.L.)
| | - Stephen A. Ward
- Centre for Drugs and Diagnostics, Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK; (S.A.W.); (G.A.B.)
| | - Giancarlo A. Biagini
- Centre for Drugs and Diagnostics, Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK; (S.A.W.); (G.A.B.)
| | - S. Samar Hasnain
- Molecular Biophysics Group, Institute of Systems, Molecular and Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Liverpool L69 7ZB, UK; (K.A.); (N.P.); (S.S.H.)
| | - Svetlana V. Antonyuk
- Molecular Biophysics Group, Institute of Systems, Molecular and Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Liverpool L69 7ZB, UK; (K.A.); (N.P.); (S.S.H.)
- Correspondence: (P.M.O.); (S.V.A.); Tel.: +44-(0)-1517955145 (S.V.A.); +44-(0)-1517943552 (P.M.O.)
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10
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Piper SJ, Johnson RM, Wootten D, Sexton PM. Membranes under the Magnetic Lens: A Dive into the Diverse World of Membrane Protein Structures Using Cryo-EM. Chem Rev 2022; 122:13989-14017. [PMID: 35849490 DOI: 10.1021/acs.chemrev.1c00837] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Membrane proteins are highly diverse in both structure and function and can, therefore, present different challenges for structure determination. They are biologically important for cells and organisms as gatekeepers for information and molecule transfer across membranes, but each class of membrane proteins can present unique obstacles to structure determination. Historically, many membrane protein structures have been investigated using highly engineered constructs or using larger fusion proteins to improve solubility and/or increase particle size. Other strategies included the deconstruction of the full-length protein to target smaller soluble domains. These manipulations were often required for crystal formation to support X-ray crystallography or to circumvent lower resolution due to high noise and dynamic motions of protein subdomains. However, recent revolutions in membrane protein biochemistry and cryo-electron microscopy now provide an opportunity to solve high resolution structures of both large, >1 megadalton (MDa), and small, <100 kDa (kDa), drug targets in near-native conditions, routinely reaching resolutions around or below 3 Å. This review provides insights into how the recent advances in membrane biology and biochemistry, as well as technical advances in cryo-electron microscopy, help us to solve structures of a large variety of membrane protein groups, from small receptors to large transporters and more complex machineries.
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Affiliation(s)
- Sarah J Piper
- Drug Discovery Biology theme, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville 3052, Victoria, Australia.,ARC Centre for Cryo-electron Microscopy of Membrane Proteins, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville 3052, Victoria, Australia
| | - Rachel M Johnson
- Drug Discovery Biology theme, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville 3052, Victoria, Australia.,ARC Centre for Cryo-electron Microscopy of Membrane Proteins, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville 3052, Victoria, Australia
| | - Denise Wootten
- Drug Discovery Biology theme, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville 3052, Victoria, Australia.,ARC Centre for Cryo-electron Microscopy of Membrane Proteins, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville 3052, Victoria, Australia
| | - Patrick M Sexton
- Drug Discovery Biology theme, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville 3052, Victoria, Australia.,ARC Centre for Cryo-electron Microscopy of Membrane Proteins, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville 3052, Victoria, Australia
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11
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Huffman AM, Ayariga JA, Napier A, Robertson BK, Abugri DA. Inhibition of Toxoplasma gondii Growth by Dihydroquinine and Its Mechanisms of Action. Front Cell Infect Microbiol 2022; 12:852889. [PMID: 35646733 PMCID: PMC9131874 DOI: 10.3389/fcimb.2022.852889] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Accepted: 02/14/2022] [Indexed: 12/17/2022] Open
Abstract
Toxoplasma gondii is a zoonotic parasite that infects the brain of humans and causes cerebral toxoplasmosis. The recommended drugs for the treatment or prophylaxis of toxoplasmosis are pyrimethamine (PY) and sulfadiazine (SZ), which have serious side effects. Other drugs available for toxoplasmosis are poorly tolerated. Dihydroquinine (DHQ) is a compound closely related to quinine-based drugs that have been shown to inhibit Plasmodium falciparum and Plasmodium berghei in addition to its anti-arrhythmia properties. However, little is known about the effect of DHQ in T. gondii growth and its mechanism of action in vitro. In this study, we report the anti-Toxoplasma and anti-invasion properties of DHQ. DHQ significantly inhibited T. gondii tachyzoite growth with IC50s values of 0.63, 0.67, and 0.00137 µM at 24, 48, and 72 h, respectively. Under similar conditions, SZ and PY, considered as the gold standard drugs for the treatment of toxoplasmosis, had IC50s values of 1.29, 1.55, and 0.95 and 3.19, 3.52, and 2.42 µM, respectively. The rapid dose-dependent inhibition of T. gondii tachyzoites by DHQ compared to the standard drugs (SZ and PY) indicates that DHQ has high selective parasiticidal effects against tachyzoite proliferation. Remarkably, DHQ had an excellent selectivity index (SI) of 149- and 357-fold compared to 24- and 143-fold for PY and SZ, respectively, using fibroblast cells. In addition, DHQ disrupted T. gondii tachyzoite mitochondrial membrane potential and adenosine triphosphate (ATP) production and elicited high reactive oxygen species (ROS) generation. Taking all these findings together, DHQ promises to be an effective and safe lead for the treatment of toxoplasmosis.
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Affiliation(s)
- Aarin M. Huffman
- Department of Biology, College of Arts and Sciences, Tuskegee University, Tuskegee, AL, United States
| | - Joseph A. Ayariga
- Department of Biological Sciences, Alabama State University, Montgomery, AL, United States
- Biomedical Engineering Program, Alabama State University, Montgomery, AL, United States
| | - Audrey Napier
- Department of Biological Sciences, Alabama State University, Montgomery, AL, United States
| | - Boakai K. Robertson
- Department of Biological Sciences, Alabama State University, Montgomery, AL, United States
- Microbiology PhD Program, College of Science, Technology, Engineering and Mathematics, Montgomery, AL, United States
| | - Daniel A. Abugri
- Department of Biological Sciences, Alabama State University, Montgomery, AL, United States
- Microbiology PhD Program, College of Science, Technology, Engineering and Mathematics, Montgomery, AL, United States
- Laboratory of Ethnomedicine, Parasitology, and Drug Discovery, College of Science, Technology, Engineering and Mathematics, Montgomery, AL, United States
- *Correspondence: Daniel A. Abugri,
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12
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Wu RZ, Zhou HY, Song JF, Xia QH, Hu W, Mou XD, Li X. Chemotherapeutics for Toxoplasma gondii: Molecular Biotargets, Binding Modes, and Structure-Activity Relationship Investigations. J Med Chem 2021; 64:17627-17655. [PMID: 34894691 DOI: 10.1021/acs.jmedchem.1c01569] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Toxoplasmosis, an infectious zoonotic disease caused by the apicomplexan parasite Toxoplasma gondii (T. gondii), is a major worldwide health problem. However, there are currently no effective options (chemotherapeutic drugs or prophylactic vaccines) for treating chronic latent toxoplasmosis infection. Accordingly, seeking more effective and safer chemotherapeutics for combating this disease remains a long-term and challenging objective. In this paper, we summarize possible molecular biotargets, with an emphasis on those that are druggable and promising, including, without limitation, calcium-dependent protein kinase 1, bifunctional thymidylate synthase-dihydrofolate reductase, and farnesyl diphosphate synthase. Meanwhile, as important components of medicinal chemistry, the binding modes and structure-activity relationship profiles of the corresponding inhibitors were also illuminated. We anticipate that this information will be helpful for further identification of more effective chemotherapeutic interventions to prevent and treat zoonotic infections caused by T. gondii.
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Affiliation(s)
- Rong-Zhen Wu
- Institute of Materia Medica, Shandong First Medical University and Shandong Academy of Medical Sciences, no. 6699 Qingdao Road, Ji'nan, Shandong 250117, PR China
| | - Huai-Yu Zhou
- Department of Pathogen Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, no. 44 Wenhua Xi Road, Ji'nan, Shandong 250012, PR China
| | - Jing-Feng Song
- School of Pharmaceutical Sciences and Yunnan Provincial Key Laboratory of Pharmacology for Natural Products, Kunming Medical University, no. 1168 Chunrong Xi Road, Kunming, Yunnan 650500, PR China
| | - Qiao-Hong Xia
- Department of Pathogen Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, no. 44 Wenhua Xi Road, Ji'nan, Shandong 250012, PR China
| | - Wei Hu
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, no. 72 Binhai Road of JiMo, Qingdao, Shandong 266237, PR China
| | - Xiao-Dong Mou
- Institute of Materia Medica, Shandong First Medical University and Shandong Academy of Medical Sciences, no. 6699 Qingdao Road, Ji'nan, Shandong 250117, PR China
| | - Xun Li
- Institute of Materia Medica, Shandong First Medical University and Shandong Academy of Medical Sciences, no. 6699 Qingdao Road, Ji'nan, Shandong 250117, PR China.,Key Laboratory of Forensic Toxicology, Ministry of Public Security, Beijing 100192, PR China
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13
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Montoya JG, Laessig K, Fazeli MS, Siliman G, Yoon SS, Drake-Shanahan E, Zhu C, Akbary A, McLeod R. A fresh look at the role of spiramycin in preventing a neglected disease: meta-analyses of observational studies. Eur J Med Res 2021; 26:143. [PMID: 34895348 PMCID: PMC8665510 DOI: 10.1186/s40001-021-00606-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Accepted: 11/14/2021] [Indexed: 12/18/2022] Open
Abstract
PURPOSE We aimed to investigate the effect of antepartum treatment with spiramycin with or without subsequent pyrimethamine-sulfonamide-folinic acid, compared to no treatment, on the rate of mother-to-child transmission (MTCT) of Toxoplasma gondii (T. gondii) and incidence/severity of sequelae in the offspring. METHODS Embase and PubMed were searched for literature on spiramycin in pregnant women suspected/diagnosed with T. gondii infection. Meta-analyses were performed using random-effects model. RESULTS Thirty-three studies (32 cohorts and 1 cross-sectional study), with a total of 15,406 mothers and 15,250 offspring, were pooled for analyses. The MTCT rate for all treated patients was significantly lower than the untreated [19.5% (95% CI 14-25.5%) versus 50.7% (95% CI 31.2-70%), p < 0.001]. The transmission rate in patients on spiramycin monotherapy was also significantly lower than untreated [17.6% (95% CI 9.9-26.8%) versus 50.7% (95% CI 31.2-70%), p < 0.001]. CONCLUSION Results indicate significant reduction in MTCT rates following spiramycin treatment of suspected/diagnosed maternal T. gondii infection.
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Affiliation(s)
- Jose G Montoya
- Jack S. Remington Laboratory for Specialty Diagnostics, Palo Alto, CA, USA
| | | | | | | | | | | | - Chengyue Zhu
- Department of General Medicines, Sanofi S.A, Bridgewater, NJ, USA
| | - Akbar Akbary
- Department of General Medicines, Sanofi S.A, Bridgewater, NJ, USA
| | - Rima McLeod
- Division of Biologic Sciences, Departments of Pediatrics (Infectious Diseases) and Ophthalmology and Visual Sciences, University of Chicago, Chicago, IL, USA.
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14
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Matta SK, Rinkenberger N, Dunay IR, Sibley LD. Toxoplasma gondii infection and its implications within the central nervous system. Nat Rev Microbiol 2021; 19:467-480. [PMID: 33627834 DOI: 10.1038/s41579-021-00518-7] [Citation(s) in RCA: 98] [Impact Index Per Article: 32.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/19/2021] [Indexed: 01/31/2023]
Abstract
Toxoplasma gondii is a parasite that infects a wide range of animals and causes zoonotic infections in humans. Although it normally only results in mild illness in healthy individuals, toxoplasmosis is a common opportunistic infection with high mortality in individuals who are immunocompromised, most commonly due to reactivation of infection in the central nervous system. In the acute phase of infection, interferon-dependent immune responses control rapid parasite expansion and mitigate acute disease symptoms. However, after dissemination the parasite differentiates into semi-dormant cysts that form within muscle cells and neurons, where they persist for life in the infected host. Control of infection in the central nervous system, a compartment of immune privilege, relies on modified immune responses that aim to balance infection control while limiting potential damage due to inflammation. In response to the activation of interferon-mediated pathways, the parasite deploys an array of effector proteins to escape immune clearance and ensure latent survival. Although these pathways are best studied in the laboratory mouse, emerging evidence points to unique mechanisms of control in human toxoplasmosis. In this Review, we explore some of these recent findings that extend our understanding for proliferation, establishment and control of toxoplasmosis in humans.
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Affiliation(s)
- Sumit K Matta
- Department of Molecular Microbiology, School of Medicine, Washington University in St. Louis, St. Louis, MO, USA
| | - Nicholas Rinkenberger
- Department of Molecular Microbiology, School of Medicine, Washington University in St. Louis, St. Louis, MO, USA
| | - Ildiko R Dunay
- Institute of Inflammation and Neurodegeneration, Otto-von-Guericke University Magdeburg, Magdeburg, Germany
| | - L David Sibley
- Department of Molecular Microbiology, School of Medicine, Washington University in St. Louis, St. Louis, MO, USA.
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