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Cabral G, Moss WJ, Brown KM. Proteomic approaches for protein kinase substrate identification in Apicomplexa. Mol Biochem Parasitol 2024:111633. [PMID: 38821187 DOI: 10.1016/j.molbiopara.2024.111633] [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: 03/30/2024] [Revised: 05/10/2024] [Accepted: 05/28/2024] [Indexed: 06/02/2024]
Abstract
Apicomplexa is a phylum of protist parasites, notable for causing life-threatening diseases including malaria, toxoplasmosis, cryptosporidiosis, and babesiosis. Apicomplexan pathogenesis is generally a function of lytic replication, dissemination, persistence, host cell modification, and immune subversion. Decades of research have revealed essential roles for apicomplexan protein kinases in establishing infections and promoting pathogenesis. Protein kinases modify their substrates by phosphorylating serine, threonine, or tyrosine residues, resulting in rapid functional changes in the target protein. Post-translational modification by phosphorylation can activate or inhibit a substrate, alter its localization, or promote interactions with other proteins or ligands. Deciphering direct kinase substrates is crucial to understand mechanisms of kinase signaling, yet can be challenging due to the transient nature of kinase phosphorylation and potential for downstream indirect phosphorylation events. However, with recent advances in proteomic approaches, our understanding of kinase function in Apicomplexa has improved dramatically. Here, we discuss methods that have been used to identify kinase substrates in apicomplexan parasites, classifying them into three main categories: i) kinase interactome, ii) indirect phosphoproteomics and iii) direct labeling. We briefly discuss each approach, including their advantages and limitations, and highlight representative examples from the Apicomplexa literature. Finally, we conclude each main category by introducing prospective approaches from other fields that would benefit kinase substrate identification in Apicomplexa.
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Affiliation(s)
- Gabriel Cabral
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - William J Moss
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Kevin M Brown
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA.
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2
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Dockterman J, Reitano JR, Everitt JI, Wallace GD, Hendrix M, Taylor GA, Coers J. Irgm proteins attenuate inflammatory disease in mouse models of genital Chlamydia infection. mBio 2024; 15:e0030324. [PMID: 38501887 PMCID: PMC11005385 DOI: 10.1128/mbio.00303-24] [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: 02/05/2024] [Accepted: 02/29/2024] [Indexed: 03/20/2024] Open
Abstract
Chlamydiae are obligate intracellular bacterial pathogens that may cause genital pathology via induction of destructive host immune responses. Human-adapted Chlamydia trachomatis causes inflammatory disease in human hosts but is easily cleared in mice, and mouse-adapted Chlamydia muridarum establishes a productive and pathogenic infection in murine hosts. While numerous anti-chlamydial host resistance factors have been discovered in mice and humans alike, little is known about host factors promoting host fitness independent of host resistance. Here, we show that interferon-inducible immunity-related GTPase M (Irgm) proteins function as such host factors ameliorating infection-associated sequalae in the murine female genital tract, thus characterizing Irgm proteins as mediators of disease tolerance. Specifically, we demonstrate that mice deficient for all three murine Irgm paralogs (pan-Irgm-/-) are defective for cell-autonomous immunity to C. trachomatis, which correlates with an early and transient increase in bacterial burden and sustained hyperinflammation in vivo. In contrast, upon infection of pan-Irgm-/- mice with C. muridarum, bacterial burden is unaffected, yet genital inflammation and scarring pathology are nonetheless increased, demonstrating that Irgm proteins can promote host fitness without altering bacterial burden. Additionally, pan-Irgm-/- mice display increased granulomatous inflammation in genital Chlamydia infection, implicating Irgm proteins in the regulation of granuloma formation and maintenance. These findings demonstrate that Irgm proteins regulate pathogenic immune responses to Chlamydia infection in vivo, establishing an effective infection model to examine the immunoregulatory functions and mechanisms of Irgm proteins. IMPORTANCE In response to genital Chlamydia infection, the immune system mounts a proinflammatory response to resist the pathogen, yet inflammation must be tightly controlled to avoid collateral damage and scarring to host genital tissue. Variation in the human IRGM gene is associated with susceptibility to autoinflammatory diseases but its role in ameliorating inflammatory diseases caused by infections is poorly defined. Here, we use mice deficient for all three murine Irgm paralogs to demonstrate that Irgm proteins not only provide host resistance to Chlamydia infections but also limit associated inflammation in the female genital tract. In particular, we find that murine Irgm expression prevents granulomatous inflammation, which parallels inflammatory diseases associated with variants in human IRGM. Our findings therefore establish genital Chlamydia infection as a useful model to study the roles for Irgm proteins in both promoting protective immunity and limiting pathogenic inflammation.
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Affiliation(s)
- Jacob Dockterman
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina, USA
- Department of Immunology, Duke University Medical Center, Durham, North Carolina, USA
| | - Jeffrey R. Reitano
- Department of Immunology, Duke University Medical Center, Durham, North Carolina, USA
| | - Jeffrey I. Everitt
- Department of Pathology, Duke University Medical Center, Durham, North Carolina, USA
| | - Graham D. Wallace
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina, USA
| | - Meghan Hendrix
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina, USA
- Department of Immunology, Duke University Medical Center, Durham, North Carolina, USA
| | - Gregory A. Taylor
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina, USA
- Department of Immunology, Duke University Medical Center, Durham, North Carolina, USA
- Geriatric Research, Education, and Clinical Center, VA Health Care Center, Durham, North Carolina, USA
- Department of Medicine, Division of Geriatrics, and Center for the Study of Aging and Human Development, Duke Universitygrid.26009.3d Medical Center, Durham, North Carolina, USA
| | - Jörn Coers
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina, USA
- Department of Immunology, Duke University Medical Center, Durham, North Carolina, USA
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Zhao XY, Lempke SL, Urbán Arroyo JC, Brown IG, Yin B, Magaj MM, Holness NK, Smiley J, Redemann S, Ewald SE. iNOS is necessary for GBP-mediated T. gondii clearance in murine macrophages via vacuole nitration and intravacuolar network collapse. Nat Commun 2024; 15:2698. [PMID: 38538595 PMCID: PMC10973475 DOI: 10.1038/s41467-024-46790-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Accepted: 03/04/2024] [Indexed: 04/02/2024] Open
Abstract
Toxoplasma gondii is an obligate intracellular parasite of rodents and humans. Interferon-inducible guanylate binding proteins (GBPs) are mediators of T. gondii clearance, however, this mechanism is incomplete. Here, using automated spatially targeted optical micro proteomics we demonstrate that inducible nitric oxide synthetase (iNOS) is highly enriched at GBP2+ parasitophorous vacuoles (PV) in murine macrophages. iNOS expression in macrophages is necessary to limit T. gondii load in vivo and in vitro. Although iNOS activity is dispensable for GBP2 recruitment and PV membrane ruffling; parasites can replicate, egress and shed GBP2 when iNOS is inhibited. T. gondii clearance by iNOS requires nitric oxide, leading to nitration of the PV and collapse of the intravacuolar network of membranes in a chromosome 3 GBP-dependent manner. We conclude that reactive nitrogen species generated by iNOS cooperate with GBPs to target distinct structures in the PV that are necessary for optimal parasite clearance in macrophages.
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Affiliation(s)
- Xiao-Yu Zhao
- Department of Microbiology, Immunology, and Cancer Biology at the Carter Immunology Center, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Samantha L Lempke
- Department of Microbiology, Immunology, and Cancer Biology at the Carter Immunology Center, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Jan C Urbán Arroyo
- Department of Microbiology, Immunology, and Cancer Biology at the Carter Immunology Center, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Isabel G Brown
- Department of Microbiology, Immunology, and Cancer Biology at the Carter Immunology Center, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Bocheng Yin
- Department of Microbiology, Immunology, and Cancer Biology at the Carter Immunology Center, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Magdalena M Magaj
- Center for Membrane and Cell Physiology, Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Nadia K Holness
- Department of Microbiology, Immunology, and Cancer Biology at the Carter Immunology Center, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Jamison Smiley
- Department of Microbiology, Immunology, and Cancer Biology at the Carter Immunology Center, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Stefanie Redemann
- Center for Membrane and Cell Physiology, Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Sarah E Ewald
- Department of Microbiology, Immunology, and Cancer Biology at the Carter Immunology Center, University of Virginia School of Medicine, Charlottesville, VA, USA.
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4
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Wang Y, Hollingsworth LR, Sangaré LO, Paredes-Santos TC, Krishnamurthy S, Penn BH, Wu H, Saeij JPJ. Host E3 ubiquitin ligase ITCH mediates Toxoplasma gondii effector GRA35-triggered NLRP1 inflammasome activation and cell-autonomous immunity. mBio 2024; 15:e0330223. [PMID: 38376248 PMCID: PMC10936166 DOI: 10.1128/mbio.03302-23] [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: 12/11/2023] [Accepted: 01/31/2024] [Indexed: 02/21/2024] Open
Abstract
Toxoplasma gondii is an intracellular parasite that can activate the NLRP1 inflammasome leading to macrophage pyroptosis in Lewis rats, but the underlying mechanism is not well understood. In this study, we performed a genome-wide CRISPR screen and identified the dense granule proteins GRA35, GRA42, and GRA43 as the Toxoplasma effectors mediating cell death in Lewis rat macrophages. GRA35 localizes on the parasitophorous vacuole membrane, where it interacts with the host E3 ubiquitin ligase ITCH. Inhibition of proteasome activity or ITCH knockout prevented pyroptosis in Toxoplasma-infected Lewis rat macrophages, consistent with the "NLRP1 functional degradation model." However, there was no evidence that ITCH directly ubiquitinates or interacts with rat NLRP1. We also found that GRA35-ITCH interaction affected Toxoplasma fitness in IFNγ-activated human fibroblasts, likely due to ITCH's role in recruiting ubiquitin and the parasite-restriction factor RNF213 to the parasitophorous vacuole membrane. These findings identify a new role of host E3 ubiquitin ligase ITCH in mediating effector-triggered immunity, a critical concept that involves recognizing intracellular pathogens and initiating host innate immune responses.IMPORTANCEEffector-triggered immunity represents an innate immune defense mechanism that plays a crucial role in sensing and controlling intracellular pathogen infection. The NLRP1 inflammasome in the Lewis rats can detect Toxoplasma infection, which triggers proptosis in infected macrophages and eliminates the parasite's replication niche. The work reported here revealed that host E3 ubiquitin ligase ITCH is able to recognize and interact with Toxoplasma effector protein GRA35 localized on the parasite-host interface, leading to NLRP1 inflammasome activation in Lewis rat macrophages. Furthermore, ITCH-GRA35 interaction contributes to the restriction of Toxoplasma in human fibroblasts stimulated by IFNγ. Thus, this research provides valuable insights into understanding pathogen recognition and restriction mediated by host E3 ubiquitin ligase.
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Affiliation(s)
- Yifan Wang
- Department of Pathology, Microbiology & Immunology, School of Veterinary Medicine, University of California, Davis, California, USA
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - L. Robert Hollingsworth
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts, USA
- Program in Cellular and Molecular Medicine, Boston Children’s Hospital, Boston, Massachusetts, USA
- Program in Biological and Biomedical Sciences, Harvard Medical School, Boston, Massachusetts, USA
| | - Lamba Omar Sangaré
- Department of Pathology, Microbiology & Immunology, School of Veterinary Medicine, University of California, Davis, California, USA
- Department of Biology, Texas A&M University, College Station, Texas, USA
| | - Tatiana C. Paredes-Santos
- Department of Pathology, Microbiology & Immunology, School of Veterinary Medicine, University of California, Davis, California, USA
| | - Shruthi Krishnamurthy
- Department of Pathology, Microbiology & Immunology, School of Veterinary Medicine, University of California, Davis, California, USA
| | - Bennett H. Penn
- Department of Internal Medicine, Division of Infectious Diseases, UC Davis Health, Sacramento, California, USA
- Department of Medical Microbiology and Immunology, University of California, Davis, California, USA
| | - Hao Wu
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts, USA
- Program in Cellular and Molecular Medicine, Boston Children’s Hospital, Boston, Massachusetts, USA
- Program in Biological and Biomedical Sciences, Harvard Medical School, Boston, Massachusetts, USA
| | - Jeroen P. J. Saeij
- Department of Pathology, Microbiology & Immunology, School of Veterinary Medicine, University of California, Davis, California, USA
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Lüder CGK. IFNs in host defence and parasite immune evasion during Toxoplasma gondii infections. Front Immunol 2024; 15:1356216. [PMID: 38384452 PMCID: PMC10879624 DOI: 10.3389/fimmu.2024.1356216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Accepted: 01/23/2024] [Indexed: 02/23/2024] Open
Abstract
Interferons (IFNs) are a family of cytokines with diverse functions in host resistance to pathogens and in immune regulation. Type II IFN, i.e. IFN-γ, is widely recognized as a major mediator of resistance to intracellular pathogens, including the protozoan Toxoplasma gondii. More recently, IFN-α/β, i.e. type I IFNs, and IFN-λ (type III IFN) have been identified to also play important roles during T. gondii infections. This parasite is a widespread pathogen of humans and animals, and it is a model organism to study cell-mediated immune responses to intracellular infection. Its success depends, among other factors, on the ability to counteract the IFN system, both at the level of IFN-mediated gene expression and at the level of IFN-regulated effector molecules. Here, I review recent advances in our understanding of the molecular mechanisms underlying IFN-mediated host resistance and immune regulation during T. gondii infections. I also discuss those mechanisms that T. gondii has evolved to efficiently evade IFN-mediated immunity. Knowledge of these fascinating host-parasite interactions and their underlying signalling machineries is crucial for a deeper understanding of the pathogenesis of toxoplasmosis, and it might also identify potential targets of parasite-directed or host-directed supportive therapies to combat the parasite more effectively.
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Affiliation(s)
- Carsten G. K. Lüder
- Institute for Medical Microbiology and Virology, University Medical Center Göttingen, Göttingen, Germany
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6
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Orchanian SB, Still K, Harris TH, Lodoen MB. Deficiency in astrocyte CCL2 production reduces neuroimmune control of Toxoplasma gondii infection. PLoS Pathog 2024; 20:e1011710. [PMID: 38206985 PMCID: PMC10807779 DOI: 10.1371/journal.ppat.1011710] [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: 02/17/2023] [Revised: 01/24/2024] [Accepted: 09/25/2023] [Indexed: 01/13/2024] Open
Abstract
Toxoplasma gondii is an obligate intracellular parasite that infects one-third of the world's human population and establishes infection in the brain. Cerebral immune cell infiltration is critical for controlling the parasite, but little is known about the molecular cues guiding immune cells to the brain during infection. Activated astrocytes produce CCL2, a chemokine that mediates inflammatory monocyte recruitment to tissues by binding to the CCR2 receptor. We detected elevated CCL2 production in the brains of C57BL/6J mice by 15 days after T. gondii infection. Utilizing confocal microscopy and intracellular flow cytometry, we identified microglia and brain-infiltrating myeloid cells as the main producers of CCL2 during acute infection, and CCL2 was specifically produced in regions of parasite infection in the brain. In contrast, astrocytes became the dominant CCL2 producer during chronic T. gondii infection. To determine the role of astrocyte-derived CCL2 in mobilizing immune cells to the brain and controlling T. gondii infection, we generated GFAP-Cre x CCL2fl/fl mice, in which astrocytes are deficient in CCL2 production. We observed significantly decreased immune cell recruitment and increased parasite burden in the brain during chronic, but not acute, infection of mice deficient in astrocyte CCL2 production, without an effect on peripheral immune responses. To investigate potential mechanisms explaining the reduced control of T. gondii infection, we analyzed key antimicrobial and immune players in host defense against T. gondii and detected a reduction in iNOS+ myeloid cells, and T. gondii-specific CD4+ T cells in the knockout mice. These data uncover a critical role for astrocyte-derived CCL2 in immune cell recruitment and parasite control in the brain during chronic, but not acute, T. gondii infection.
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Affiliation(s)
- Stephanie B. Orchanian
- Department of Molecular Biology and Biochemistry, University of California, Irvine, Irvine, California, United States of America
- Institute for Immunology, University of California, Irvine, Irvine, California, United States of America
| | - Katherine Still
- Center for Brain Immunology and Glia, Department of Neuroscience, University of Virginia, Charlottesville, Virginia, United States of America
| | - Tajie H. Harris
- Center for Brain Immunology and Glia, Department of Neuroscience, University of Virginia, Charlottesville, Virginia, United States of America
| | - Melissa B. Lodoen
- Department of Molecular Biology and Biochemistry, University of California, Irvine, Irvine, California, United States of America
- Institute for Immunology, University of California, Irvine, Irvine, California, United States of America
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Henry B, Sibley LD, Rosenberg A. A Combination of Four Nuclear Targeted Effectors Protects Toxoplasma Against Interferon Gamma Driven Human Host Cell Death During Acute Infection. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.24.573224. [PMID: 38234811 PMCID: PMC10793417 DOI: 10.1101/2023.12.24.573224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2024]
Abstract
In both mice and humans, Type II interferon-gamma (IFNγ) is crucial for regulation of Toxoplasma gondii (T. gondii) infection, during acute or chronic phases. To thwart this defense, T. gondii secretes protein effectors hindering the hosťs immune response. For example, T. gondii relies on the MYR translocon complex to deploy soluble dense granule effectors (GRAs) into the host cell cytosol or nucleus. Recent genome-wide loss-of-function screens in IFNγ-primed primary human fibroblasts identified MYR translocon components as crucial for parasite resistance against IFNγ driven vacuole clearance. However, these screens did not pinpoint specific MYR-dependent GRA proteins responsible for IFNγ signaling blockade, suggesting potential functional redundancy. Our study reveals that T. gondii depends on the MYR translocon complex to prevent host cell death and parasite premature egress in human cells stimulated with IFNγ postinfection, a unique phenotype observed in various human cell lines but not in murine cells. Intriguingly, inhibiting parasite egress did not prevent host cell death, indicating this mechanism is distinct from those described previously. Genome-wide loss-of-function screens uncovered TgIST, GRA16, GRA24, and GRA28 as effectors necessary for a complete block of IFNγ response. GRA24 and GRA28 directly influenced IFNγ driven transcription, GRA24's action depended on its interaction with p38 MAPK, while GRA28 disrupted histone acetyltransferase activity of CBP/p300. Given the intricate nature of the immune response to T. gondii, it appears that the parasite has evolved equally elaborate mechanisms to subvert IFNγ signaling, extending beyond direct interference with the JAK/STAT1 pathway, to encompass other signaling pathways as well.
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Affiliation(s)
- Brittany Henry
- Department of Infectious Diseases, Center for Tropical and Emerging Infectious Diseases, University of Georgia, Athens, Georgia, USA
| | - L. David Sibley
- Department of Molecular Microbiology, Washington University School of Medicine, St Louis, Missouri, USA
| | - Alex Rosenberg
- Department of Infectious Diseases, Center for Tropical and Emerging Infectious Diseases, University of Georgia, Athens, Georgia, USA
- Department of Molecular Microbiology, Washington University School of Medicine, St Louis, Missouri, USA
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Teixeira SC, Teixeira TL, Tavares PCB, Alves RN, da Silva AA, Borges BC, Martins FA, Dos Santos MA, de Castilhos P, E Silva Brígido RT, Notário AFO, Silveira ACA, da Silva CV. Subversion strategies of lysosomal killing by intracellular pathogens. Microbiol Res 2023; 277:127503. [PMID: 37748260 DOI: 10.1016/j.micres.2023.127503] [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: 07/16/2023] [Revised: 09/08/2023] [Accepted: 09/17/2023] [Indexed: 09/27/2023]
Abstract
Many pathogenic organisms need to reach either an intracellular compartment or the cytoplasm of a target cell for their survival, replication or immune system evasion. Intracellular pathogens frequently penetrate into the cell through the endocytic and phagocytic pathways (clathrin-mediated endocytosis, phagocytosis and macropinocytosis) that culminates in fusion with lysosomes. However, several mechanisms are triggered by pathogenic microorganisms - protozoan, bacteria, virus and fungus - to avoid destruction by lysosome fusion, such as rupture of the phagosome and thereby release into the cytoplasm, avoidance of autophagy, delaying in both phagolysosome biogenesis and phagosomal maturation and survival/replication inside the phagolysosome. Here we reviewed the main data dealing with phagosome maturation and evasion from lysosomal killing by different bacteria, protozoa, fungi and virus.
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Affiliation(s)
- Samuel Cota Teixeira
- Instituto de Ciências Biomédicas, Universidade Federal de Uberlândia, Uberlândia, MG, Brazil
| | - Thaise Lara Teixeira
- Instituto de Ciências Biomédicas, Universidade Federal de Uberlândia, Uberlândia, MG, Brazil
| | | | | | - Aline Alves da Silva
- Instituto de Ciências Biomédicas, Universidade Federal de Uberlândia, Uberlândia, MG, Brazil
| | - Bruna Cristina Borges
- Instituto de Ciências Biomédicas, Universidade Federal de Uberlândia, Uberlândia, MG, Brazil
| | - Flávia Alves Martins
- Instituto de Ciências Biomédicas, Universidade Federal de Uberlândia, Uberlândia, MG, Brazil
| | - Marlus Alves Dos Santos
- Instituto de Ciências Biomédicas, Universidade Federal de Uberlândia, Uberlândia, MG, Brazil
| | - Patrícia de Castilhos
- Instituto de Ciências Biomédicas, Universidade Federal de Uberlândia, Uberlândia, MG, Brazil
| | | | | | | | - Claudio Vieira da Silva
- Instituto de Ciências Biomédicas, Universidade Federal de Uberlândia, Uberlândia, MG, Brazil.
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9
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Thind AC, Mota CM, Gonçalves APN, Sha J, Wohlschlegel JA, Mineo TWP, Bradley PJ. The Toxoplasma gondii effector GRA83 modulates the host's innate immune response to regulate parasite infection. mSphere 2023; 8:e0026323. [PMID: 37768053 PMCID: PMC10597413 DOI: 10.1128/msphere.00263-23] [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: 05/12/2023] [Accepted: 08/07/2023] [Indexed: 09/29/2023] Open
Abstract
Toxoplasma gondii's propensity to infect its host and cause disease is highly dependent on its ability to modulate host cell functions. One of the strategies the parasite uses to accomplish this is via the export of effector proteins from the secretory dense granules. Dense granule (GRA) proteins are known to play roles in nutrient acquisition, host cell cycle manipulation, and immune regulation. Here, we characterize a novel dense granule protein named GRA83, which localizes to the parasitophorous vacuole (PV) in tachyzoites and bradyzoites. Disruption of GRA83 results in increased virulence, weight loss, and parasitemia during the acute infection, as well as a marked increase in the cyst burden during the chronic infection. This increased parasitemia was associated with an accumulation of inflammatory infiltrates in tissues in both acute and chronic infections. Murine macrophages infected with ∆gra83 tachyzoites produced less interleukin-12 (IL-12) in vitro, which was confirmed with reduced IL-12 and interferon-gamma in vivo. This dysregulation of cytokines correlates with reduced nuclear translocation of the p65 subunit of the nuclear factor-κB (NF-κB) complex. While GRA15 similarly regulates NF-κB, infection with ∆gra83/∆gra15 parasites did not further reduce p65 translocation to the host cell nucleus, suggesting these GRAs function in converging pathways. We also used proximity labeling experiments to reveal candidate GRA83 interacting T. gondii-derived partners. Taken together, this work reveals a novel effector that stimulates the innate immune response, enabling the host to limit the parasite burden. Importance Toxoplasma gondii poses a significant public health concern as it is recognized as one of the leading foodborne pathogens in the United States. Infection with the parasite can cause congenital defects in neonates, life-threatening complications in immunosuppressed patients, and ocular disease. Specialized secretory organelles, including the dense granules, play an important role in the parasite's ability to efficiently invade and regulate components of the host's infection response machinery to limit parasite clearance and establish an acute infection. Toxoplasma's ability to avoid early clearance, while also successfully infecting the host long enough to establish a persistent chronic infection, is crucial in allowing for its transmission to a new host. While multiple GRAs directly modulate host signaling pathways, they do so in various ways highlighting the parasite's diverse arsenal of effectors that govern infection. Understanding how parasite-derived effectors harness host functions to evade defenses yet ensure a robust infection is important for understanding the complexity of the pathogen's tightly regulated infection. In this study, we characterize a novel secreted protein named GRA83 that stimulates the host cell's response to limit infection.
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Affiliation(s)
- Amara C. Thind
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, California, USA
- Molecular Biology Institute, University of California, Los Angeles, Los Angeles, California, USA
| | - Caroline M. Mota
- Laboratory of Immunoparasitology “Dr. Mário Endsfeldz Camargo,” Institute of Biomedical Sciences, Federal University of Uberlândia, Uberlândia, Minas Gerais, Brazil
| | - Ana Paula N. Gonçalves
- Laboratory of Immunoparasitology “Dr. Mário Endsfeldz Camargo,” Institute of Biomedical Sciences, Federal University of Uberlândia, Uberlândia, Minas Gerais, Brazil
| | - Jihui Sha
- Department of Biological Chemistry, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California, USA
| | - James A. Wohlschlegel
- Department of Biological Chemistry, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California, USA
| | - Tiago W. P. Mineo
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, California, USA
- Laboratory of Immunoparasitology “Dr. Mário Endsfeldz Camargo,” Institute of Biomedical Sciences, Federal University of Uberlândia, Uberlândia, Minas Gerais, Brazil
| | - Peter J. Bradley
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, California, USA
- Molecular Biology Institute, University of California, Los Angeles, Los Angeles, California, USA
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10
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Orchanian SB, Lodoen MB. Monocytes as primary defenders against Toxoplasma gondii infection. Trends Parasitol 2023; 39:837-849. [PMID: 37633758 DOI: 10.1016/j.pt.2023.07.007] [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: 04/11/2023] [Revised: 07/14/2023] [Accepted: 07/21/2023] [Indexed: 08/28/2023]
Abstract
Monocytes are recruited from the bone marrow to sites of infection where they release cytokines and chemokines, function in antimicrobial immunity, and differentiate into macrophages and dendritic cells to control infection. Although many studies have focused on monocyte-derived macrophages and dendritic cells, recent work has examined the unique roles of monocytes during infection to promote immune defense. We focus on the effector functions of monocytes during infection with the parasite Toxoplasma gondii, and discuss the signals that mobilize monocytes to sites of infection, their production of inflammatory cytokines and antimicrobial mediators, their ability to shape the adaptive immune response, and their immunoregulatory functions. Insights from other infections, including Plasmodium and Listeria are also included for comparison and context.
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Affiliation(s)
- Stephanie B Orchanian
- Department of Molecular Biology and Biochemistry, University of California Irvine, Irvine, California, USA; Institute for Immunology, University of California Irvine, Irvine, California, USA
| | - Melissa B Lodoen
- Department of Molecular Biology and Biochemistry, University of California Irvine, Irvine, California, USA; Institute for Immunology, University of California Irvine, Irvine, California, USA.
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11
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Ha HJ, Kim JH, Lee GH, Kim S, Park HH. Structural basis of IRGB10 oligomerization by GTP hydrolysis. Front Immunol 2023; 14:1254415. [PMID: 37705969 PMCID: PMC10495984 DOI: 10.3389/fimmu.2023.1254415] [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: 07/07/2023] [Accepted: 08/11/2023] [Indexed: 09/15/2023] Open
Abstract
Immunity-related GTPase B10 (IRGB10) is a crucial member of the interferon (IFN)-inducible GTPases and plays a vital role in host defense mechanisms. Following infection, IRGB10 is induced by IFNs and functions by liberating pathogenic ligands to activate the inflammasome through direct disruption of the pathogen membrane. Despite extensive investigation into the significance of the cell-autonomous immune response, the precise molecular mechanism underlying IRGB10-mediated microbial membrane disruption remains elusive. Herein, we present two structures of different forms of IRGB10, the nucleotide-free and GppNHp-bound forms. Based on these structures, we identified that IRGB10 exists as a monomer in nucleotide-free and GTP binding states. Additionally, we identified that GTP hydrolysis is critical for dimer formation and further oligomerization of IRGB10. Building upon these observations, we propose a mechanistic model to elucidate the working mechanism of IRGB10 during pathogen membrane disruption.
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Affiliation(s)
- Hyun Ji Ha
- College of Pharmacy, Chung-Ang University, Seoul, Republic of Korea
| | - Ju Hyeong Kim
- College of Pharmacy, Chung-Ang University, Seoul, Republic of Korea
- Department of Global Innovative Drugs, Graduate School of Chung-Ang University, Seoul, Republic of Korea
| | - Gwan Hee Lee
- College of Pharmacy, Chung-Ang University, Seoul, Republic of Korea
- Department of Global Innovative Drugs, Graduate School of Chung-Ang University, Seoul, Republic of Korea
| | - Subin Kim
- College of Pharmacy, Chung-Ang University, Seoul, Republic of Korea
- Department of Global Innovative Drugs, Graduate School of Chung-Ang University, Seoul, Republic of Korea
| | - Hyun Ho Park
- College of Pharmacy, Chung-Ang University, Seoul, Republic of Korea
- Department of Global Innovative Drugs, Graduate School of Chung-Ang University, Seoul, Republic of Korea
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12
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Zhao XY, Lempke SL, Urbán Arroyo JC, Yin B, Holness NK, Smiley J, Ewald SE. Inducible nitric oxide synthase (iNOS) is necessary for GBP-mediated T. gondii restriction in murine macrophages via vacuole nitration and intravacuolar network collapse. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.24.549965. [PMID: 37546987 PMCID: PMC10402109 DOI: 10.1101/2023.07.24.549965] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/08/2023]
Abstract
Toxoplasma gondii is an obligate intracellular, protozoan pathogen of rodents and humans. T. gondii's ability to grow within cells and evade cell-autonomous immunity depends on the integrity of the parasitophorous vacuole (PV). Interferon-inducible guanylate binding proteins (GBPs) are central mediators of T. gondii clearance, however, the precise mechanism linking GBP recruitment to the PV and T. gondii restriction is not clear. This knowledge gap is linked to heterogenous GBP-targeting across a population of vacuoles and the lack of tools to selectively purify the intact PV. To identify mediators of parasite clearance associated with GBP2-positive vacuoles, we employed a novel protein discovery tool automated spatially targeted optical micro proteomics (autoSTOMP). This approach identified inducible nitric oxide synthetase (iNOS) enriched at levels similar to the GBPs in infected bone marrow-derived myeloid cells. iNOS expression on myeloid cells was necessary for mice to control T. gondii growth in vivo and survive acute infection. T. gondii infection of IFNγ-primed macrophage was sufficient to robustly induce iNOS expression. iNOS restricted T. gondii infection through nitric oxide synthesis rather than arginine depletion, leading to robust and selective nitration of the PV. Optimal parasite restriction by iNOS and vacuole nitration depended on the chromosome 3 GBPs. Notably, GBP2 recruitment and ruffling of the PV membrane occurred in iNOS knockouts, however, these vacuoles contained dividing parasites. iNOS activity was necessary for the collapse of the intravacuolar network of nanotubular membranes which connects parasites to each other and the host cytosol. Based on these data we conclude reactive nitrogen species generated by iNOS cooperate with the chromosome 3 GBPs to target distinct biology of the PV that are necessary for optimal parasite clearance in murine myeloid cells.
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Affiliation(s)
- Xiao-Yu Zhao
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia School of Medicine, Charlottesville, Virginia, USA
- The Carter Immunology Center, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - Samantha L. Lempke
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia School of Medicine, Charlottesville, Virginia, USA
- The Carter Immunology Center, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - Jan C. Urbán Arroyo
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia School of Medicine, Charlottesville, Virginia, USA
- The Carter Immunology Center, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - Bocheng Yin
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia School of Medicine, Charlottesville, Virginia, USA
- The Carter Immunology Center, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - Nadia K. Holness
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia School of Medicine, Charlottesville, Virginia, USA
- The Carter Immunology Center, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - Jamison Smiley
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia School of Medicine, Charlottesville, Virginia, USA
- The Carter Immunology Center, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - Sarah E. Ewald
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia School of Medicine, Charlottesville, Virginia, USA
- The Carter Immunology Center, University of Virginia School of Medicine, Charlottesville, Virginia, USA
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13
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Thind AC, Mota CM, Gonçalves APN, Sha J, Wohlschlegel JA, Mineo TWP, Bradley PJ. The Toxoplasma gondii effector GRA83 modulates the host's innate immune response to regulate parasite infection. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.31.543158. [PMID: 37398161 PMCID: PMC10312501 DOI: 10.1101/2023.05.31.543158] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/04/2023]
Abstract
Toxoplasma gondii 's propensity to infect its host and cause disease is highly dependent on its ability to modulate host cell functions. One of the strategies the parasite uses to accomplish this is via the export of effector proteins from the secretory dense granules. Dense granule (GRA) proteins are known to play roles in nutrient acquisition, host cell cycle manipulation, and immune regulation. Here, we characterize a novel dense granule protein named GRA83, which localizes to the parasitophorous vacuole in tachyzoites and bradyzoites. Disruption of GRA83 results in increased virulence, weight loss, and parasitemia during the acute infection, as well as a marked increase in the cyst burden during the chronic infection. This increased parasitemia was associated with an accumulation of inflammatory infiltrates in tissues in both the acute and chronic infection. Murine macrophages infected with Δ gra83 tachyzoites produced less interleukin-12 (IL-12) in vitro , which was confirmed with reduced IL-12 and interferon gamma (IFN-γ) in vivo . This dysregulation of cytokines correlates with reduced nuclear translocation of the p65 subunit of the NF-κB complex. While GRA15 similarly regulates NF-κB, infection with Δ gra83/ Δ gra15 parasites did not further reduce p65 translocation to the host cell nucleus, suggesting these GRAs function in converging pathways. We also used proximity labelling experiments to reveal candidate GRA83 interacting T. gondii derived partners. Taken together, this work reveals a novel effector that stimulates the innate immune response, enabling the host to limit parasite burden. Importance Toxoplasma gondii poses a significant public health concern as it is recognized as one of the leading foodborne pathogens in the United States. Infection with the parasite can cause congenital defects in neonates, life-threatening complications in immunosuppressed patients, and ocular disease. Specialized secretory organelles, including the dense granules, play an important role in the parasite's ability to efficiently invade and regulate components of the host's infection response machinery to limit parasite clearance and establish an acute infection. Toxoplasma' s ability to avoid early clearance, while also successfully infecting the host long enough to establish a persistent chronic infection, is crucial in allowing for its transmission to a new host. While multiple GRAs directly modulate host signaling pathways, they do so in various ways highlighting the parasite's diverse arsenal of effectors that govern infection. Understanding how parasite-derived effectors harness host functions to evade defenses yet ensure a robust infection are important for understanding the complexity of the pathogen's tightly regulated infection. In this study, we characterize a novel secreted protein named GRA83 that stimulates the host cell's response to limit infection.
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14
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CRISPR Screens Identify Toxoplasma Genes That Determine Parasite Fitness in Interferon Gamma-Stimulated Human Cells. mBio 2023; 14:e0006023. [PMID: 36916910 PMCID: PMC10128063 DOI: 10.1128/mbio.00060-23] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023] Open
Abstract
Toxoplasma virulence depends on its ability to evade or survive the toxoplasmacidal mechanisms induced by interferon gamma (IFNγ). While many Toxoplasma genes involved in the evasion of the murine IFNγ response have been identified, genes required to survive the human IFNγ response are largely unknown. In this study, we used a genome-wide loss-of-function screen to identify Toxoplasma genes important for parasite fitness in IFNγ-stimulated primary human fibroblasts. We generated gene knockouts for the top six hits from the screen and confirmed their importance for parasite growth in IFNγ-stimulated human fibroblasts. Of these six genes, three have homology to GRA32, localize to dense granules, and coimmunoprecipitate with each other and GRA32, suggesting they might form a complex. Deletion of individual members of this complex leads to early parasite egress in IFNγ-stimulated cells. Thus, prevention of early egress is an important Toxoplasma fitness determinant in IFNγ-stimulated human cells. IMPORTANCE Toxoplasma infection causes serious complications in immunocompromised individuals and in the developing fetus. During infection, certain immune cells release a protein called interferon gamma that activates cells to destroy the parasite or inhibit its growth. While most Toxoplasma parasites are cleared by this immune response, some can survive by blocking or evading the IFNγ-induced restrictive environment. Many Toxoplasma genes that determine parasite survival in IFNγ-activated murine cells are known but parasite genes conferring fitness in IFNγ-activated human cells are largely unknown. Using a Toxoplasma adapted genome-wide loss-of-function screen, we identified many Toxoplasma genes that determine parasite fitness in IFNγ-activated human cells. The gene products of four top hits play a role in preventing early parasite egress in IFNγ-stimulated human cells. Understanding how IFNγ-stimulated human cells inhibit Toxoplasma growth and how Toxoplasma counteracts this, could lead to the development of novel therapeutics.
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15
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Romano PS, Akematsu T, Besteiro S, Bindschedler A, Carruthers VB, Chahine Z, Coppens I, Descoteaux A, Alberto Duque TL, He CY, Heussler V, Le Roch KG, Li FJ, de Menezes JPB, Menna-Barreto RFS, Mottram JC, Schmuckli-Maurer J, Turk B, Tavares Veras PS, Salassa BN, Vanrell MC. Autophagy in protists and their hosts: When, how and why? AUTOPHAGY REPORTS 2023; 2:2149211. [PMID: 37064813 PMCID: PMC10104450 DOI: 10.1080/27694127.2022.2149211] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2022] [Accepted: 11/15/2022] [Indexed: 03/12/2023]
Abstract
Pathogenic protists are a group of organisms responsible for causing a variety of human diseases including malaria, sleeping sickness, Chagas disease, leishmaniasis, and toxoplasmosis, among others. These diseases, which affect more than one billion people globally, mainly the poorest populations, are characterized by severe chronic stages and the lack of effective antiparasitic treatment. Parasitic protists display complex life-cycles and go through different cellular transformations in order to adapt to the different hosts they live in. Autophagy, a highly conserved cellular degradation process, has emerged as a key mechanism required for these differentiation processes, as well as other functions that are crucial to parasite fitness. In contrast to yeasts and mammals, protist autophagy is characterized by a modest number of conserved autophagy-related proteins (ATGs) that, even though, can drive the autophagosome formation and degradation. In addition, during their intracellular cycle, the interaction of these pathogens with the host autophagy system plays a crucial role resulting in a beneficial or harmful effect that is important for the outcome of the infection. In this review, we summarize the current state of knowledge on autophagy and other related mechanisms in pathogenic protists and their hosts. We sought to emphasize when, how, and why this process takes place, and the effects it may have on the parasitic cycle. A better understanding of the significance of autophagy for the protist life-cycle will potentially be helpful to design novel anti-parasitic strategies.
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Affiliation(s)
- Patricia Silvia Romano
- Laboratorio de Biología de Trypanosoma cruzi y de la célula hospedadora. Instituto de Histología y Embriología de Mendoza. Universidad Nacional de Cuyo. (IHEM-CONICET-UNCUYO). Facultad de Ciencias Médicas. Universidad Nacional de Cuyo. Av. Libertador 80 (5500), Mendoza, Argentina
| | - Takahiko Akematsu
- Department of Biosciences, College of Humanities and Sciences, Nihon University, Tokyo, Japan
| | | | | | - Vern B Carruthers
- Department of Microbiology and Immunology, University of Michigan School of Medicine, Ann Arbor, MI, USA
| | - Zeinab Chahine
- Department of Molecular, Cell and Systems Biology, University of California Riverside, CA, USA
| | - Isabelle Coppens
- Department of Molecular Microbiology and Immunology. Department of Molecular Microbiology and Immunology. Johns Hopkins Malaria Research Institute. Johns Hopkins University Bloomberg School of Public Health. Baltimore 21205, MD, USA
| | - Albert Descoteaux
- Centre Armand-Frappier Santé Biotechnologie, Institut national de la recherche scientifique, Laval, QC
| | - Thabata Lopes Alberto Duque
- Autophagy Inflammation and Metabolism Center, University of New Mexico Health Sciences Center, Albuquerque, NM, USA; Department of Molecular Genetics and Microbiology, University of New Mexico Health Sciences Center, Albuquerque, NM, USA
| | - Cynthia Y He
- Department of Biological Sciences, National University of Singapore, Singapore
| | - Volker Heussler
- Institute of Cell Biology.University of Bern. Baltzerstr. 4 3012 Bern
| | - Karine G Le Roch
- Department of Molecular, Cell and Systems Biology, University of California Riverside, CA, USA
| | - Feng-Jun Li
- Department of Biological Sciences, National University of Singapore, Singapore
| | | | | | - Jeremy C Mottram
- York Biomedical Research Institute, Department of Biology, University of York, York, UK
| | | | - Boris Turk
- Department of Biochemistry and Molecular and Structural Biology, Jožef Stefan Institute, SI-1000 Ljubljana, Slovenia
| | - Patricia Sampaio Tavares Veras
- Laboratory of Host-Parasite Interaction and Epidemiology, Gonçalo Moniz Institute, Fiocruz-Bahia
- National Institute of Science and Technology of Tropical Diseases - National Council for Scientific Research and Development (CNPq)
| | - Betiana Nebai Salassa
- Laboratorio de Biología de Trypanosoma cruzi y de la célula hospedadora. Instituto de Histología y Embriología de Mendoza. Universidad Nacional de Cuyo. (IHEM-CONICET-UNCUYO). Facultad de Ciencias Médicas. Universidad Nacional de Cuyo. Av. Libertador 80 (5500), Mendoza, Argentina
| | - María Cristina Vanrell
- Laboratorio de Biología de Trypanosoma cruzi y de la célula hospedadora. Instituto de Histología y Embriología de Mendoza. Universidad Nacional de Cuyo. (IHEM-CONICET-UNCUYO). Facultad de Ciencias Médicas. Universidad Nacional de Cuyo. Av. Libertador 80 (5500), Mendoza, Argentina
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16
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Murillo-León M, Bastidas-Quintero AM, Endres NS, Schnepf D, Delgado-Betancourt E, Ohnemus A, Taylor GA, Schwemmle M, Staeheli P, Steinfeldt T. IFN-λ is protective against lethal oral Toxoplasma gondii infection. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.24.529861. [PMID: 36865100 PMCID: PMC9980175 DOI: 10.1101/2023.02.24.529861] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/27/2023]
Abstract
Interferons are essential for innate and adaptive immune responses against a wide variety of pathogens. Interferon lambda (IFN-λ) protects mucosal barriers during pathogen exposure. The intestinal epithelium is the first contact site for Toxoplasma gondii (T. gondii) with its hosts and the first defense line that limits parasite infection. Knowledge of very early T. gondii infection events in the gut tissue is limited and a possible contribution of IFN-λ has not been investigated so far. Here, we demonstrate with systemic interferon lambda receptor (IFNLR1) and conditional (Villin-Cre) knockout mouse models and bone marrow chimeras of oral T. gondii infection and mouse intestinal organoids a significant impact of IFN-λ signaling in intestinal epithelial cells and neutrophils to T. gondii control in the gastrointestinal tract. Our results expand the repertoire of interferons that contribute to the control of T. gondii and may lead to novel therapeutic approaches against this world-wide zoonotic pathogen.
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Affiliation(s)
- Mateo Murillo-León
- Institute of Virology, Medical Center University of Freiburg, 79104 Freiburg, Germany
- Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
- Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany
| | - Aura M. Bastidas-Quintero
- Institute of Virology, Medical Center University of Freiburg, 79104 Freiburg, Germany
- Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
- Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany
| | - Niklas S. Endres
- Institute of Virology, Medical Center University of Freiburg, 79104 Freiburg, Germany
- Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
- Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany
- Current address:Institute of Virology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
| | - Daniel Schnepf
- Institute of Virology, Medical Center University of Freiburg, 79104 Freiburg, Germany
- Current address: Immunoregulation Laboratory, The Francis Crick Institute, London, UK
| | | | - Annette Ohnemus
- Institute of Virology, Medical Center University of Freiburg, 79104 Freiburg, Germany
- Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
| | - Gregory A. Taylor
- Departments of Medicine; Molecular Genetics and Microbiology; and Immunology; and Center for the Study of Aging and Human Development, Duke University Medical Center, NC 27710 Durham, North Carolina, United States of America
- Geriatric Research, Education, and Clinical Center, Durham VA Health Care System, NC 27705 Durham, North Carolina, United States of America
| | - Martin Schwemmle
- Institute of Virology, Medical Center University of Freiburg, 79104 Freiburg, Germany
- Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
| | - Peter Staeheli
- Institute of Virology, Medical Center University of Freiburg, 79104 Freiburg, Germany
- Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
| | - Tobias Steinfeldt
- Institute of Virology, Medical Center University of Freiburg, 79104 Freiburg, Germany
- Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
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17
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Hansakon A, Ngamphiw C, Tongsima S, Angkasekwinai P. Arginase 1 Expression by Macrophages Promotes Cryptococcus neoformans Proliferation and Invasion into Brain Microvascular Endothelial Cells. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2023; 210:408-419. [PMID: 36548474 DOI: 10.4049/jimmunol.2200592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Accepted: 11/30/2022] [Indexed: 12/24/2022]
Abstract
Cryptococcal meningoencephalitis caused by Cryptococcus neoformans infection is the most common cause of death in HIV/AIDS patients. Macrophages are pivotal for the regulation of immune responses to cryptococcal infection by either playing protective function or facilitating fungal dissemination. However, the mechanisms underlying macrophage responses to C. neoformans remain unclear. To analyze the transcriptomic changes and identify the pathogenic factors of macrophages, we performed a comparative transcriptomic analysis of alveolar macrophage responses during C. neoformans infection. Alveolar macrophages isolated from C. neoformans-infected mice showed dynamic gene expression patterns, with expression change from a protective M1 (classically activated)-like to a pathogenic M2 (alternatively activated)-like phenotype. Arg1, the gene encoding the enzyme arginase 1, was found as the most upregulated gene in alveolar macrophages during the chronic infection phase. The in vitro inhibition of arginase activity resulted in a reduction of cryptococcal phagocytosis, intracellular growth, and proliferation, coupled with an altered macrophage response from pathogenic M2 to a protective M1 phenotype. In an in vitro model of the blood-brain barrier, macrophage-derived arginase was found to be required for C. neoformans invasion of brain microvascular endothelium. Further analysis of the degree of virulence indicated a positive correlation between arginase 1 expression in macrophages and cryptococcal brain dissemination in vivo. Thus, our data suggest that a dynamic macrophage activation that involves arginase expression may contribute to the cryptococcal disease by promoting cryptococcal growth, proliferation, and the invasion to the brain endothelium.
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Affiliation(s)
- Adithap Hansakon
- Department of Medical Technology, Faculty of Allied Health Sciences, Thammasat University, Pathum Thani, Thailand.,Chulabhorn International College of Medicine, Thammasat University, Pathum Thani, Thailand
| | - Chumpol Ngamphiw
- National Biobank of Thailand, National Science and Technology Development Agency, Pathum Thani, Thailand; and
| | - Sissades Tongsima
- National Biobank of Thailand, National Science and Technology Development Agency, Pathum Thani, Thailand; and
| | - Pornpimon Angkasekwinai
- Department of Medical Technology, Faculty of Allied Health Sciences, Thammasat University, Pathum Thani, Thailand.,Research Unit in Molecular Pathogenesis and Immunology of Infectious Diseases, Thammasat University, Pathum Thani, Thailand
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18
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Deng S, Graham ML, Chen XM. The Complexity of Interferon Signaling in Host Defense against Protozoan Parasite Infection. Pathogens 2023; 12:pathogens12020319. [PMID: 36839591 PMCID: PMC9962834 DOI: 10.3390/pathogens12020319] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 02/11/2023] [Accepted: 02/13/2023] [Indexed: 02/17/2023] Open
Abstract
Protozoan parasites, such as Plasmodium, Leishmania, Toxoplasma, Cryptosporidium, and Trypanosoma, are causative agents of health-threatening diseases in both humans and animals, leading to significant health risks and socioeconomic losses globally. The development of effective therapeutic and prevention strategies for protozoan-caused diseases requires a full understanding of the pathogenesis and protective events occurring in infected hosts. Interferons (IFNs) are a family of cytokines with diverse biological effects in host antimicrobial defense and disease pathogenesis, including protozoan parasite infection. Type II IFN (IFN-γ) has been widely recognized as the essential defense cytokine in intracellular protozoan parasite infection, whereas recent studies also revealed the production and distinct function of type I and III IFNs in host defense against these parasites. Decoding the complex network of the IFN family in host-parasite interaction is critical for exploring potential new therapeutic strategies against intracellular protozoan parasite infection. Here, we review the complex effects of IFNs on the host defense against intracellular protozoan parasites and the crosstalk between distinct types of IFN signaling during infections.
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Affiliation(s)
- Silu Deng
- Department of Microbial Pathogens and Immunity, Rush University Medical Center, Chicago, IL 60612, USA
- Department of Medical Microbiology and Immunology, Creighton University School of Medicine, Omaha, NE 68178, USA
| | - Marion L. Graham
- Department of Microbial Pathogens and Immunity, Rush University Medical Center, Chicago, IL 60612, USA
| | - Xian-Ming Chen
- Department of Microbial Pathogens and Immunity, Rush University Medical Center, Chicago, IL 60612, USA
- Correspondence:
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19
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Nano-Encapsulated Antioxidant: Retinoic Acid as a Natural Mucosal Adjuvant for Intranasal Immunization against Chronic Experimental Toxoplasmosis. Trop Med Infect Dis 2023; 8:tropicalmed8020106. [PMID: 36828522 PMCID: PMC9962073 DOI: 10.3390/tropicalmed8020106] [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: 12/01/2022] [Revised: 01/12/2023] [Accepted: 02/02/2023] [Indexed: 02/10/2023] Open
Abstract
The tight relationship between immunity and retinoid levels provides evidence on the critical role of retinoic acid (RA) in regulating immune activity, especially the mucosal one. Mucosal immune response is the key for determination of the outcome of infection, particularly against intracellular mucosal pathogens such as Toxoplasma gondii, where it plays a crucial role as a sentinel against parasite invasion. Herein, the immunomodulatory adjuvant role of RA was evaluated for prophylactic vaccination against chronic Toxoplasma infection. A quantity of 15 µg of RA pre-encapsulated with lipid-based nanoparticles (SLNs) was intranasally used in three doses, two weeks apart, as an adjuvant to the Toxoplasma lysate antigen (TLA). Afterward, mice were infected with 20 cysts of T. gondii (ME49 strain) and were sacrificed at the 4th week post-infection. Parasitological, immunological, biochemical, and histopathological studies were applied as vaccine efficacy measures. The protective role of the tested vaccine was noted using the statistically marked reduction in brain cyst count, accompanied by remarkable levels of protective IFN-γ and antibodies, with amelioration of infection-induced oxidative stress and brain pathology. Ultimately, this experiment outlined the prospective role of a novel, natural, nano-encapsulated and mucosal vaccine adjuvant RA-SLNs as a propitious candidate against chronic toxoplasmosis.
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20
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Overview of Apoptosis, Autophagy, and Inflammatory Processes in Toxoplasma gondii Infected Cells. Pathogens 2023; 12:pathogens12020253. [PMID: 36839525 PMCID: PMC9966443 DOI: 10.3390/pathogens12020253] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 01/30/2023] [Accepted: 02/02/2023] [Indexed: 02/08/2023] Open
Abstract
Toxoplasma gondii (T. gondii) is an obligate intracellular parasite. During the parasitic invasion, T. gondii creates a parasitophorous vacuole, which enables the modulation of cell functions, allowing its replication and host infection. It has effective strategies to escape the immune response and reach privileged immune sites and remain inactive in a controlled environment in tissue cysts. This current review presents the factors that affect host cells and the parasite, as well as changes in the immune system during host cell infection. The secretory organelles of T. gondii (dense granules, micronemes, and rhoptries) are responsible for these processes. They are involved with proteins secreted by micronemes and rhoptries (MIC, AMA, and RONs) that mediate the recognition and entry into host cells. Effector proteins (ROP and GRA) that modify the STAT signal or GTPases in immune cells determine their toxicity. Interference byhost autonomous cells during parasitic infection, gene expression, and production of microbicidal molecules such as reactive oxygen species (ROS) and nitric oxide (NO), result in the regulation of cell death. The high level of complexity in host cell mechanisms prevents cell death in its various pathways. Many of these abilities play an important role in escaping host immune responses, particularly by manipulating the expression of genes involved in apoptosis, necrosis, autophagy, and inflammation. Here we present recent works that define the mechanisms by which T. gondii interacts with these processes in infected host cells.
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21
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Singh S, Murillo-León M, Endres NS, Arenas Soto AF, Gómez-Marín JE, Melbert F, Kanneganti TD, Yamamoto M, Campos C, Howard JC, Taylor GA, Steinfeldt T. ROP39 is an Irgb10-specific parasite effector that modulates acute Toxoplasma gondii virulence. PLoS Pathog 2023; 19:e1011003. [PMID: 36603017 PMCID: PMC9848475 DOI: 10.1371/journal.ppat.1011003] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Revised: 01/18/2023] [Accepted: 11/14/2022] [Indexed: 01/06/2023] Open
Abstract
Toxoplasma gondii (T. gondii) is a zoonotic apicomplexan parasite that is an important cause of clinical disability in humans. On a global scale, one third of the human population is infected with T. gondii. Mice and other small rodents are believed to be responsible for transmission of T. gondii to the domestic cat, its definitive host. Interferon-inducible Immunity-Related GTPases (IRG proteins) are important for control of murine T. gondii infections. Virulence differences between T. gondii strains are linked to polymorphic rhoptry proteins (ROPs) that cooperate to inactivate individual IRG family members. In particular, the pseudokinase ROP5 isoform B is critically important in laboratory strains of mice. We identified T. gondii ROP39 in complex with ROP5B and demonstrate its contribution to acute T. gondii virulence. ROP39 directly targets Irgb10 and inhibits homodimer formation of the GTPase leading to an overall reduction of IRG protein loading onto the parasitophorous vacuolar membrane (PVM). Maintenance of PVM integrity rescues the parasite from IRG protein-mediated clearance in vitro and in vivo. This study identifies a novel T. gondii effector that is important for specific inactivation of the IRG resistance system. Our data reveal that yet unknown T. gondii effectors can emerge from identification of direct interaction partners of ROP5B.
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Affiliation(s)
- Shishir Singh
- Institute of Virology, Medical Center University of Freiburg, Freiburg, Germany
- Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Mateo Murillo-León
- Institute of Virology, Medical Center University of Freiburg, Freiburg, Germany
- Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Niklas Sebastian Endres
- Institute of Virology, Medical Center University of Freiburg, Freiburg, Germany
- Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Ailan Farid Arenas Soto
- Grupo GEPAMOL, Centro de Investigaciones Biomedicas, Universidad del Quindio, Armenia, Quindio, Colombia
| | - Jorge Enrique Gómez-Marín
- Grupo GEPAMOL, Centro de Investigaciones Biomedicas, Universidad del Quindio, Armenia, Quindio, Colombia
| | - Florence Melbert
- Institute of Virology, Medical Center University of Freiburg, Freiburg, Germany
- Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Thirumala-Devi Kanneganti
- Department of Immunology, St. Jude Children´s Research Hospital, Memphis, Tenessee, United States of America
| | - Masahiro Yamamoto
- Department of Immunoparasitology, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, Japan
- Laboratory of Immunoparasitology, World Premier International Immunology Frontier Research Center, Osaka University, Suita, Osaka, Japan
| | - Claudia Campos
- Fundacao Calouste Gulbekian, Instituto Gulbekian de Ciencia, Oeiras, Portugal
| | | | - Gregory Alan Taylor
- Departments of Medicine; Molecular Genetics and Microbiology; and Immunology; and Center for the Study of Aging and Human Development, Duke University Medical Center, Durham, North Carolina, United States of America
- Geriatric Research, Education, and Clinical Center, Durham VA Health Care System, Durham, North Carolina, United States of America
| | - Tobias Steinfeldt
- Institute of Virology, Medical Center University of Freiburg, Freiburg, Germany
- Faculty of Medicine, University of Freiburg, Freiburg, Germany
- * E-mail:
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22
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Said DE, Amer EI, Sheta E, Makled S, Diab HE, Arafa FM. Nano-Encapsulated Melatonin: A Promising Mucosal Adjuvant in Intranasal Immunization against Chronic Experimental T. gondii Infection. Trop Med Infect Dis 2022; 7:tropicalmed7120401. [PMID: 36548656 PMCID: PMC9785012 DOI: 10.3390/tropicalmed7120401] [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: 10/24/2022] [Revised: 11/17/2022] [Accepted: 11/24/2022] [Indexed: 11/29/2022] Open
Abstract
Melatonin (MLT) is now emerging as one of the universally accepted immunostimulators with broad applications in medicine. It is a biological manipulator of the immune system, including mucosal ones. MLT was encapsulated in solid lipid nanoparticles (SLNs), then 100 mg/kg/dose of MLT-SLNs was used as an adjuvant of Toxoplasma lysate antigen (TLA). Experimental mice were intra-nasally inoculated with three doses of different regimens every two weeks, then challenged with 20 cysts of T. gondii Me49 strain, where they were sacrificed four weeks post-infection. Protective vaccine efficacy was evident via the significant brain cyst count reduction of 58.6%, together with remarkably high levels of humoral systemic and mucosal anti-Toxoplasma antibodies (Ig G, Ig A), supported by a reduced tachyzoites invasion of Vero cells in vitro upon incubation with sera obtained from these vaccinated mice. A cellular immune response was evident through the induction of significant levels of interferon-gamma (IFN γ), associated with morphological deteriorations of cysts harvested from the brains of vaccinated mice. Furthermore, the amelioration of infection-induced oxidative stress (OS) and histopathological changes were evident in mice immunized with TLA/MLT-SLNs. In conclusion, the present study highlighted the promising role of intranasal MLT-SLNs as a novel mucosal adjuvant candidate against chronic toxoplasmosis.
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Affiliation(s)
- Doaa E. Said
- Department of Medical Parasitology, Faculty of Medicine, Alexandria University, Alexandria 5424041, Egypt
| | - Eglal I. Amer
- Department of Medical Parasitology, Faculty of Medicine, Alexandria University, Alexandria 5424041, Egypt
| | - Eman Sheta
- Department of Pathology, Faculty of Medicine, Alexandria University, Alexandria 5424041, Egypt
| | - Shaimaa Makled
- Department of Pharmaceutics, Faculty of Pharmacy, Alexandria University, Alexandria 21521, Egypt
| | - Hala E. Diab
- Department of Medical Parasitology, Faculty of Medicine, Alexandria University, Alexandria 5424041, Egypt
- Correspondence:
| | - Fadwa M. Arafa
- Department of Medical Parasitology, Faculty of Medicine, Alexandria University, Alexandria 5424041, Egypt
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23
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Pant A, Yao X, Lavedrine A, Viret C, Dockterman J, Chauhan S, Chong-Shan Shi, Manjithaya R, Cadwell K, Kufer TA, Kehrl JH, Coers J, Sibley LD, Faure M, Taylor GA, Chauhan S. Interactions of Autophagy and the Immune System in Health and Diseases. AUTOPHAGY REPORTS 2022; 1:438-515. [PMID: 37425656 PMCID: PMC10327624 DOI: 10.1080/27694127.2022.2119743] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/07/2023]
Abstract
Autophagy is a highly conserved process that utilizes lysosomes to selectively degrade a variety of intracellular cargo, thus providing quality control over cellular components and maintaining cellular regulatory functions. Autophagy is triggered by multiple stimuli ranging from nutrient starvation to microbial infection. Autophagy extensively shapes and modulates the inflammatory response, the concerted action of immune cells, and secreted mediators aimed to eradicate a microbial infection or to heal sterile tissue damage. Here, we first review how autophagy affects innate immune signaling, cell-autonomous immune defense, and adaptive immunity. Then, we discuss the role of non-canonical autophagy in microbial infections and inflammation. Finally, we review how crosstalk between autophagy and inflammation influences infectious, metabolic, and autoimmune disorders.
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Affiliation(s)
- Aarti Pant
- Autophagy Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, India
| | - Xiaomin Yao
- Kimmel Center for Biology and Medicine at the Skirball Institute, New York University Grossman School of Medicine, New York, New York, United States of America
- Department of Microbiology, New York University Grossman School of Medicine, New York, New York, United States of America
| | - Aude Lavedrine
- CIRI, Centre International de Recherche en Infectiologie, Université de Lyon, Inserm U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, ENS de Lyon, F-69007, Lyon, France
- Equipe Labellisée par la Fondation pour la Recherche Médicale, FRM
| | - Christophe Viret
- CIRI, Centre International de Recherche en Infectiologie, Université de Lyon, Inserm U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, ENS de Lyon, F-69007, Lyon, France
- Equipe Labellisée par la Fondation pour la Recherche Médicale, FRM
| | - Jake Dockterman
- Department of Immunology, Duke University, Medical Center, Durham, North Carolina, USA
| | - Swati Chauhan
- Cell biology and Infectious diseases, Institute of Life Sciences, Bhubaneswar, India
| | - Chong-Shan Shi
- Laboratory of Immunoregulation, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Ravi Manjithaya
- Autophagy Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, India
- Neuroscience Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, India
| | - Ken Cadwell
- Kimmel Center for Biology and Medicine at the Skirball Institute, New York University Grossman School of Medicine, New York, New York, United States of America
- Department of Microbiology, New York University Grossman School of Medicine, New York, New York, United States of America
- Division of Gastroenterology and Hepatology, Department of Medicine, New York University Grossman School of Medicine, New York, New York, United States of America
| | - Thomas A. Kufer
- Department of Immunology, Institute of Nutritional Medicine, University of Hohenheim, Stuttgart, Germany
| | - John H. Kehrl
- Laboratory of Immunoregulation, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Jörn Coers
- Department of Immunology, Duke University, Medical Center, Durham, North Carolina, USA
- Department of Molecular Genetics and Microbiology, Duke University, Medical Center, Durham, North Carolina, USA
| | - L. David Sibley
- Department of Molecular Microbiology, Washington University Sch. Med., St Louis, MO, 63110, USA
| | - Mathias Faure
- CIRI, Centre International de Recherche en Infectiologie, Université de Lyon, Inserm U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, ENS de Lyon, F-69007, Lyon, France
- Equipe Labellisée par la Fondation pour la Recherche Médicale, FRM
| | - Gregory A Taylor
- Department of Immunology, Duke University, Medical Center, Durham, North Carolina, USA
- Department of Molecular Genetics and Microbiology, Duke University, Medical Center, Durham, North Carolina, USA
- Department of Molecular Microbiology, Washington University Sch. Med., St Louis, MO, 63110, USA
- Geriatric Research, Education, and Clinical Center, VA Health Care Center, Durham, North Carolina, USA
- Departments of Medicine, Division of Geriatrics, and Center for the Study of Aging and Human Development, Duke University, Medical Center, Durham, North Carolina, USA
| | - Santosh Chauhan
- Cell biology and Infectious diseases, Institute of Life Sciences, Bhubaneswar, India
- CSIR–Centre For Cellular And Molecular Biology (CCMB), Hyderabad, Telangana
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24
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Dockterman J, Coers J. How did we get here? Insights into mechanisms of immunity-related GTPase targeting to intracellular pathogens. Curr Opin Microbiol 2022; 69:102189. [PMID: 35963099 PMCID: PMC9745802 DOI: 10.1016/j.mib.2022.102189] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 06/28/2022] [Accepted: 07/11/2022] [Indexed: 12/15/2022]
Abstract
The cytokine gamma-interferon activates cell-autonomous immunity against intracellular bacterial and protozoan pathogens by inducing a slew of antimicrobial proteins, some of which hinge upon immunity-related GTPases (IRGs) for their function. Three regulatory IRG clade M (Irgm) proteins chaperone about approximately 20 effector IRGs (GKS IRGs) to localize to pathogen-containing vacuoles (PVs) within mouse cells, initiating a cascade that results in PV elimination and killing of PV-resident pathogens. However, the mechanisms that allow IRGs to identify and traffic specifically to 'non-self' PVs have remained elusive. Integrating recent findings demonstrating direct interactions between GKS IRGs and lipids with previous work, we propose that three attributes mark PVs as GKS IRG targets: the absence of membrane-bound Irgm proteins, Atg8 lipidation, and the presence of specific lipid species. Combinatorial recognition of these three distinct signals may have evolved as a mechanism to ensure safe delivery of potent host antimicrobial effectors exclusively to PVs.
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Affiliation(s)
- Jacob Dockterman
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Jörn Coers
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA.
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25
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Interferon-Inducible E3 Ligase RNF213 Facilitates Host-Protective Linear and K63-Linked Ubiquitylation of Toxoplasma gondii Parasitophorous Vacuoles. mBio 2022; 13:e0188822. [PMID: 36154443 PMCID: PMC9601232 DOI: 10.1128/mbio.01888-22] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The obligate intracellular protozoan pathogen Toxoplasma gondii infects a wide range of vertebrate hosts and frequently causes zoonotic infections in humans. Whereas infected immunocompetent individuals typically remain asymptomatic, toxoplasmosis in immunocompromised individuals can manifest as a severe, potentially lethal disease, and congenital Toxoplasma infections are associated with adverse pregnancy outcomes. The protective immune response of healthy individuals involves the production of lymphocyte-derived cytokines such as interferon gamma (IFN-γ), which elicits cell-autonomous immunity in host cells. IFN-γ-inducible antiparasitic defense programs comprise nutritional immunity, the production of noxious gases, and the ubiquitylation of the Toxoplasma-containing parasitophorous vacuole (PV). PV ubiquitylation prompts the recruitment of host defense proteins to the PV and the consequential execution of antimicrobial effector programs, which reduce parasitic burden. However, the ubiquitin E3 ligase orchestrating these events has remained unknown. Here, we demonstrate that the IFN-γ-inducible E3 ligase RNF213 translocates to Toxoplasma PVs and facilitates PV ubiquitylation in human cells. Toxoplasma PVs become decorated with linear and K63-linked ubiquitin and recruit ubiquitin adaptor proteins in a process that is RNF213 dependent but independent of the linear ubiquitin chain assembly complex (LUBAC). IFN-γ priming fails to restrict Toxoplasma growth in cells lacking RNF213 expression, thus identifying RNF213 as a potent executioner of ubiquitylation-driven antiparasitic host defense.
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26
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Chandrasekaran S, Kochanowsky JA, Merritt EF, Lagas JS, Swannigan A, Koshy AA. IFN-γ stimulated murine and human neurons mount anti-parasitic defenses against the intracellular parasite Toxoplasma gondii. Nat Commun 2022; 13:4605. [PMID: 35941154 PMCID: PMC9360015 DOI: 10.1038/s41467-022-32225-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Accepted: 07/19/2022] [Indexed: 01/13/2023] Open
Abstract
Dogma holds that Toxoplasma gondii persists in neurons because neurons cannot clear intracellular parasites, even with IFN-γ stimulation. As several recent studies questioned this idea, here we use primary murine neuronal cultures from wild type and transgenic mice in combination with IFN-γ stimulation and parental and transgenic parasites to reassess IFN-γ dependent neuronal clearance of intracellular parasites. We find that neurons respond to IFN-γ and that a subset of neurons clear intracellular parasites via immunity regulated GTPases. Whole neuron reconstructions from mice infected with parasites that trigger neuron GFP expression only after full invasion reveal that ~50% of these T. gondii-invaded neurons no longer harbor parasites. Finally, IFN-γ stimulated human pluripotent stem cell derived neurons show an ~50% decrease in parasite infection rate when compared to unstimulated cultures. This work highlights the capability of human and murine neurons to mount cytokine-dependent anti-T. gondii defense mechanisms in vitro and in vivo.
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Affiliation(s)
| | - Joshua A Kochanowsky
- Department of Immunobiology, University of Arizona, Tucson, AZ, USA
- University of California, Los Angeles, CA, USA
| | - Emily F Merritt
- Department of Immunobiology, University of Arizona, Tucson, AZ, USA
| | - Joseph S Lagas
- Undergraduate Biology Research Program, University of Arizona, Tucson, AZ, USA
| | - Ayesha Swannigan
- Undergraduate Research Opportunities Consortium, University of Arizona, Tucson, AZ, USA
| | - Anita A Koshy
- BIO5 Institute, University of Arizona, Tucson, AZ, USA.
- Department of Immunobiology, University of Arizona, Tucson, AZ, USA.
- Department of Neurology, University of Arizona, Tucson, AZ, USA.
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27
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Zhang Z, Xun Y, Rong S, Yan L, SoRelle JA, Li X, Tang M, Keller K, Ludwig S, Moresco EMY, Beutler B. Loss of immunity-related GTPase GM4951 leads to nonalcoholic fatty liver disease without obesity. Nat Commun 2022; 13:4136. [PMID: 35842425 PMCID: PMC9288484 DOI: 10.1038/s41467-022-31812-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2021] [Accepted: 07/05/2022] [Indexed: 11/30/2022] Open
Abstract
Obesity and diabetes are well known risk factors for nonalcoholic fatty liver disease (NAFLD), but the genetic factors contributing to the development of NAFLD remain poorly understood. Here we describe two semi-dominant allelic missense mutations (Oily and Carboniferous) of Predicted gene 4951 (Gm4951) identified from a forward genetic screen in mice. GM4951 deficient mice developed NAFLD on high fat diet (HFD) with no changes in body weight or glucose metabolism. Moreover, HFD caused a reduction in the level of Gm4951, which in turn promoted the development of NAFLD. Predominantly expressed in hepatocytes, GM4951 was verified as an interferon inducible GTPase. The NAFLD in Gm4951 knockout mice was associated with decreased lipid oxidation in the liver and no defect in hepatic lipid secretion. After lipid loading, hepatocyte GM4951 translocated to lipid droplets (LDs), bringing with it hydroxysteroid 17β-dehydrogenase 13 (HSD17B13), which in the absence of GM4951 did not undergo this translocation. We identified a rare non-obese mouse model of NAFLD caused by GM4951 deficiency and define a critical role for GTPase-mediated translocation in hepatic lipid metabolism.
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Affiliation(s)
- Zhao Zhang
- Center for the Genetics of Host Defense, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA. .,Division of Endocrinology, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA.
| | - Yu Xun
- grid.267313.20000 0000 9482 7121Center for the Genetics of Host Defense, University of Texas Southwestern Medical Center, Dallas, TX 75390 USA ,grid.267313.20000 0000 9482 7121Division of Endocrinology, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390 USA
| | - Shunxing Rong
- grid.267313.20000 0000 9482 7121Center for Human Nutrition, University of Texas Southwestern Medical Center, Dallas, TX 75390 USA ,grid.267313.20000 0000 9482 7121Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX 75390 USA
| | - Lijuan Yan
- grid.267313.20000 0000 9482 7121Center for the Genetics of Host Defense, University of Texas Southwestern Medical Center, Dallas, TX 75390 USA
| | - Jeffrey A. SoRelle
- grid.267313.20000 0000 9482 7121Center for the Genetics of Host Defense, University of Texas Southwestern Medical Center, Dallas, TX 75390 USA
| | - Xiaohong Li
- grid.267313.20000 0000 9482 7121Center for the Genetics of Host Defense, University of Texas Southwestern Medical Center, Dallas, TX 75390 USA
| | - Miao Tang
- grid.267313.20000 0000 9482 7121Center for the Genetics of Host Defense, University of Texas Southwestern Medical Center, Dallas, TX 75390 USA
| | - Katie Keller
- grid.267313.20000 0000 9482 7121Center for the Genetics of Host Defense, University of Texas Southwestern Medical Center, Dallas, TX 75390 USA
| | - Sara Ludwig
- grid.267313.20000 0000 9482 7121Center for the Genetics of Host Defense, University of Texas Southwestern Medical Center, Dallas, TX 75390 USA
| | - Eva Marie Y. Moresco
- grid.267313.20000 0000 9482 7121Center for the Genetics of Host Defense, University of Texas Southwestern Medical Center, Dallas, TX 75390 USA
| | - Bruce Beutler
- Center for the Genetics of Host Defense, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA.
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28
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Wu M, An R, Zhou N, Chen Y, Cai H, Yan Q, Wang R, Luo Q, Yu L, Chen L, Du J. Toxoplasma gondii CDPK3 Controls the Intracellular Proliferation of Parasites in Macrophages. Front Immunol 2022; 13:905142. [PMID: 35757711 PMCID: PMC9226670 DOI: 10.3389/fimmu.2022.905142] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2022] [Accepted: 05/16/2022] [Indexed: 11/30/2022] Open
Abstract
Interferon-γ (IFN-γ)-activated macrophages restrain the replication of intracellular parasites and disrupt the integrity of vacuolar pathogens. The growth of the less virulent type II strain of Toxoplasma gondii (such as ME49) was strongly inhibited by IFN-γ-activated murine macrophages. However, the mechanism of resistance is poorly understood. Immunity-related GTPases (IRGs) as well as guanylate-binding proteins (GBPs) contributed to this antiparasitic effect. Previous studies showed the cassette of autophagy-related proteins including Atg7, Atg3, and Atg12-Atg5-Atg16L1 complex, plays crucial roles in the proper targeting of IFN-γ effectors onto the parasitophorous vacuole (PV) membrane of Toxoplasma gondii and subsequent control of parasites. TgCDPK3 is a calcium dependent protein kinase, located on the parasite periphery, plays a crucial role in parasite egress. Herein, we show that the less virulent strain CDPK3 (ME49, type II) can enhance autophagy activation and interacts with host autophagy proteins Atg3 and Atg5. Infection with CDPK3-deficient ME49 strain resulted in decreased localization of IRGs and GBPs around PV membrane. In vitro proliferation and plaque assays showed that CDPK3-deficient ME49 strain replicated significantly more quickly than wild-type parasites. These data suggested that TgCDPK3 interacts with the host Atg3 and Atg5 to promote the localization of IRGs and GBPs around PV membrane and inhibits the intracellular proliferation of parasites, which is beneficial to the less virulent strain of Toxoplasma gondii long-term latency in host cells.
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Affiliation(s)
- Minmin Wu
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China.,The Research Center for Infectious Diseases, School of Basic Medical Sciences, Anhui Medical University, Hefei, China.,The Provincial Key Laboratory of Zoonoses of High Institutions of Anhui, Anhui Medical University, Hefei, China.,The Key Laboratory of Microbiology and Parasitology of Anhui Province, Anhui Medical University, Hefei, China
| | - Ran An
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China.,The Research Center for Infectious Diseases, School of Basic Medical Sciences, Anhui Medical University, Hefei, China.,The Provincial Key Laboratory of Zoonoses of High Institutions of Anhui, Anhui Medical University, Hefei, China.,The Key Laboratory of Microbiology and Parasitology of Anhui Province, Anhui Medical University, Hefei, China
| | - Nan Zhou
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China.,The Research Center for Infectious Diseases, School of Basic Medical Sciences, Anhui Medical University, Hefei, China.,The Provincial Key Laboratory of Zoonoses of High Institutions of Anhui, Anhui Medical University, Hefei, China.,The Key Laboratory of Microbiology and Parasitology of Anhui Province, Anhui Medical University, Hefei, China
| | - Ying Chen
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China.,The Research Center for Infectious Diseases, School of Basic Medical Sciences, Anhui Medical University, Hefei, China.,The Provincial Key Laboratory of Zoonoses of High Institutions of Anhui, Anhui Medical University, Hefei, China.,School of Nursing, Anhui Medical University, Hefei, China
| | - Haijian Cai
- The Research Center for Infectious Diseases, School of Basic Medical Sciences, Anhui Medical University, Hefei, China.,The Provincial Key Laboratory of Zoonoses of High Institutions of Anhui, Anhui Medical University, Hefei, China
| | - Qi Yan
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China.,The Research Center for Infectious Diseases, School of Basic Medical Sciences, Anhui Medical University, Hefei, China.,The Provincial Key Laboratory of Zoonoses of High Institutions of Anhui, Anhui Medical University, Hefei, China.,The Key Laboratory of Microbiology and Parasitology of Anhui Province, Anhui Medical University, Hefei, China
| | - Ru Wang
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China.,The Research Center for Infectious Diseases, School of Basic Medical Sciences, Anhui Medical University, Hefei, China.,The Provincial Key Laboratory of Zoonoses of High Institutions of Anhui, Anhui Medical University, Hefei, China.,The Key Laboratory of Microbiology and Parasitology of Anhui Province, Anhui Medical University, Hefei, China
| | - Qingli Luo
- The Provincial Key Laboratory of Zoonoses of High Institutions of Anhui, Anhui Medical University, Hefei, China.,The Key Laboratory of Microbiology and Parasitology of Anhui Province, Anhui Medical University, Hefei, China
| | - Li Yu
- The Research Center for Infectious Diseases, School of Basic Medical Sciences, Anhui Medical University, Hefei, China.,The Provincial Key Laboratory of Zoonoses of High Institutions of Anhui, Anhui Medical University, Hefei, China.,The Key Laboratory of Microbiology and Parasitology of Anhui Province, Anhui Medical University, Hefei, China
| | - Lijian Chen
- Department of Anesthesiology, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Jian Du
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China.,The Research Center for Infectious Diseases, School of Basic Medical Sciences, Anhui Medical University, Hefei, China.,The Provincial Key Laboratory of Zoonoses of High Institutions of Anhui, Anhui Medical University, Hefei, China.,The Key Laboratory of Microbiology and Parasitology of Anhui Province, Anhui Medical University, Hefei, China
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29
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Sasai M, Yamamoto M. Anti-toxoplasma host defense systems and the parasitic counterdefense mechanisms. Parasitol Int 2022; 89:102593. [DOI: 10.1016/j.parint.2022.102593] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 04/12/2022] [Accepted: 04/26/2022] [Indexed: 10/18/2022]
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30
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Abstract
The gene RARRES3 uses an unexpected strategy to eliminate the parasite Toxoplasma gondii from human cells.
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Affiliation(s)
- Juan C Sánchez-Arcila
- Department of Molecular and Cell Biology, University of California Merced, Merced, United States
| | - Kirk Dc Jensen
- Department of Molecular and Cell Biology, University of California Merced, Merced, United States.,Health Science Research Institute, University of California, Merced, Merced, United States
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31
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Zheng Q, Duan L, Zhang Y, Li J, Zhang S, Wang H. A dynamically evolving war between autophagy and pathogenic microorganisms. J Zhejiang Univ Sci B 2022; 23:19-41. [PMID: 35029086 PMCID: PMC8758936 DOI: 10.1631/jzus.b2100285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Autophagy is an intracellular degradation process that maintains cellular homeostasis. It is essential for protecting organisms from environmental stress. Autophagy can help the host to eliminate invading pathogens, including bacteria, viruses, fungi, and parasites. However, pathogens have evolved multiple strategies to interfere with autophagic signaling pathways or inhibit the fusion of autophagosomes with lysosomes to form autolysosomes. Moreover, host cell matrix degradation by different types of autophagy can be used for the proliferation and reproduction of pathogens. Thus, determining the roles and mechanisms of autophagy during pathogen infections will promote understanding of the mechanisms of pathogen‒host interactions and provide new strategies for the treatment of infectious diseases.
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Affiliation(s)
- Qianqian Zheng
- Henan Key Laboratory of Immunology and Targeted Drugs, School of Laboratory Medicine, Xinxiang Medical University, Xinxiang 453003, China.,Henan Collaborative Innovation Center of Molecular Diagnosis and Laboratory Medicine, Xinxiang Medical University, Xinxiang 453003, China
| | - Liangwei Duan
- Henan Key Laboratory of Immunology and Targeted Drugs, School of Laboratory Medicine, Xinxiang Medical University, Xinxiang 453003, China.,Henan Collaborative Innovation Center of Molecular Diagnosis and Laboratory Medicine, Xinxiang Medical University, Xinxiang 453003, China
| | - Yang Zhang
- Henan Key Laboratory of Immunology and Targeted Drugs, School of Laboratory Medicine, Xinxiang Medical University, Xinxiang 453003, China.,Henan Collaborative Innovation Center of Molecular Diagnosis and Laboratory Medicine, Xinxiang Medical University, Xinxiang 453003, China
| | - Jiaoyang Li
- Henan Key Laboratory of Immunology and Targeted Drugs, School of Laboratory Medicine, Xinxiang Medical University, Xinxiang 453003, China.,Henan Collaborative Innovation Center of Molecular Diagnosis and Laboratory Medicine, Xinxiang Medical University, Xinxiang 453003, China
| | - Shiyu Zhang
- Henan Key Laboratory of Immunology and Targeted Drugs, School of Laboratory Medicine, Xinxiang Medical University, Xinxiang 453003, China.,Henan Collaborative Innovation Center of Molecular Diagnosis and Laboratory Medicine, Xinxiang Medical University, Xinxiang 453003, China
| | - Hui Wang
- Henan Key Laboratory of Immunology and Targeted Drugs, School of Laboratory Medicine, Xinxiang Medical University, Xinxiang 453003, China. .,Henan Collaborative Innovation Center of Molecular Diagnosis and Laboratory Medicine, Xinxiang Medical University, Xinxiang 453003, China.
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Sana M, Rashid M, Rashid I, Akbar H, Gomez-Marin JE, Dimier-Poisson I. Immune response against toxoplasmosis-some recent updates RH: Toxoplasma gondii immune response. Int J Immunopathol Pharmacol 2022; 36:3946320221078436. [PMID: 35227108 PMCID: PMC8891885 DOI: 10.1177/03946320221078436] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
AIMS Cytokines, soluble mediators of immunity, are key factors of the innate and adaptive immune system. They are secreted from and interact with various types of immune cells to manipulate host body's immune cell physiology for a counter-attack on the foreign body. A study was designed to explore the mechanism of Toxoplasma gondii (T. gondii) resistance from host immune response. METHODS AND RESULTS The published data on aspect of host (murine and human) immune response against T. gondii was taken from Google scholar and PubMed. Most relevant literature was included in this study. The basic mechanism of immune response starts from the interactions of antigens with host immune cells to trigger the production of cytokines (pro-inflammatory and anti-inflammatory) which then act by forming a cytokinome (network of cytokine). Their secretory equilibrium is essential for endowing resistance to the host against infectious diseases, particularly toxoplasmosis. A narrow balance lying between Th1, Th2, and Th17 cytokines (as demonstrated until now) is essential for the development of resistance against T. gondii as well as for the survival of host. Excessive production of pro-inflammatory cytokines leads to tissue damage resulting in the production of anti-inflammatory cytokines which enhances the proliferation of Toxoplasma. Stress and other infectious diseases (human immunodeficiency virus (HIV)) that weaken the host immunity particularly the cellular component, make the host susceptible to toxoplasmosis especially in pregnant women. CONCLUSION The current review findings state that in vitro harvesting of IL12 from DCs, Np and MΦ upon exposure with T. gondii might be a source for therapeutic use in toxoplasmosis. Current review also suggests that therapeutic interventions leading to up-regulation/supplementation of SOCS-3, IL12, and IFNγ to the infected host could be a solution to sterile immunity against T. gondii infection. This would be of interest particularly in patients passing through immunosuppression owing to any reason like the ones receiving anti-cancer therapy, the ones undergoing immunosuppressive therapy for graft/transplantation, the ones suffering from immunodeficiency virus (HIV) or having AIDS. Another imortant suggestion is to launch the efforts for a vaccine based on GRA6Nt or other similar antigens of T. gondii as a probable tool to destroy tissue cysts.
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Affiliation(s)
- Madiha Sana
- Department of Parasitology, 66920University of Veterinary and Animal Sciences, Lahore, Pakistan
| | - Muhammad Rashid
- Department of Parasitology, Faculty of Veterinary and Animal Sciences, 66920The Islamia University of Bahawalpur, Pakistan
| | - Imran Rashid
- Department of Parasitology, 66920University of Veterinary and Animal Sciences, Lahore, Pakistan
| | - Haroon Akbar
- Department of Parasitology, 66920University of Veterinary and Animal Sciences, Lahore, Pakistan
| | - Jorge E Gomez-Marin
- Grupo Gepamol, Centro de Investigaciones Biomedicas, Universidad del Quindio, Armenia, CO, South America
| | - Isabelle Dimier-Poisson
- Université de Tours, Institut national de recherche pour l'agriculture, l'alimentation et l'environnement (INRAE), Unité mixte de recherche 1282 (UMR1282), Infectiologie et santé publique (ISP), Tours, France
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Abstract
Toxoplasma gondii is a parasitic protist infecting a wide group of warm-blooded animals, ranging from birds to humans. While this infection is usually asymptomatic in healthy individuals, it can also lead to severe ocular or neurological outcomes in immunocompromised individuals or in developing fetuses. This obligate intracellular parasite has the ability to infect a considerable range of nucleated cells and can propagate in the intermediate host. Yet, under the pressure of the immune system it transforms into an encysted persistent form residing primarily in the brain and muscle tissues. Encysted parasites, which are resistant to current medication, may reactivate and give rise to an acute infection. The clinical outcome of toxoplasmosis depends on a complex balance between the host immune response and parasite virulence factors. Susceptibility to the disease is thus determined by both parasite strains and host species. Recent advances on our understanding of host cell-parasite interactions and parasite virulence have brought new insights into the pathophysiology of T. gondii infection and are summarized here.
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Rinkenberger N, Abrams ME, Matta SK, Schoggins JW, Alto NM, Sibley LD. Over-expression screen of interferon-stimulated genes identifies RARRES3 as a restrictor of Toxoplasma gondii infection. eLife 2021; 10:73137. [PMID: 34871166 PMCID: PMC8789288 DOI: 10.7554/elife.73137] [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: 08/17/2021] [Accepted: 12/05/2021] [Indexed: 12/26/2022] Open
Abstract
Toxoplasma gondii is an important human pathogen infecting an estimated one in three people worldwide. The cytokine interferon gamma (IFNγ) is induced during infection and is critical for restricting T. gondii growth in human cells. Growth restriction is presumed to be due to the induction of interferon-stimulated genes (ISGs) that are upregulated to protect the host from infection. Although there are hundreds of ISGs induced by IFNγ, their individual roles in restricting parasite growth in human cells remain somewhat elusive. To address this deficiency, we screened a library of 414 IFNγ induced ISGs to identify factors that impact T. gondii infection in human cells. In addition to IRF1, which likely acts through the induction of numerous downstream genes, we identified RARRES3 as a single factor that restricts T. gondii infection by inducing premature egress of the parasite in multiple human cell lines. Overall, while we successfully identified a novel IFNγ induced factor restricting T. gondii infection, the limited number of ISGs capable of restricting T. gondii infection when individually expressed suggests that IFNγ-mediated immunity to T. gondii infection is a complex, multifactorial process.
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Affiliation(s)
- Nicholas Rinkenberger
- Department of Molecular Microbiology, Washington University in St. Louis, St Louis, United States
| | - Michael E Abrams
- Department of Microbiology, The University of Texas Southwestern Medical Center, Dallas, United States
| | - Sumit K Matta
- Department of Molecular Microbiology, Washington University in St. Louis, St Louis, United States
| | - John W Schoggins
- Department of Microbiology, The University of Texas Southwestern Medical Center, Dallas, United States
| | - Neal M Alto
- Microbiology, University of Texas Southwestern Medical Center, Dallas, United States
| | - L David Sibley
- Department of Molecular Microbiology, Washington University in St. Louis, St Louis, United States
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35
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Lodoen MB, Smith NC, Soldati-Favre D, Ferguson DJP, van Dooren GG. Nanos gigantium humeris insidentes: old papers informing new research into Toxoplasma gondii. Int J Parasitol 2021; 51:1193-1212. [PMID: 34736901 PMCID: PMC10538201 DOI: 10.1016/j.ijpara.2021.10.004] [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: 09/14/2021] [Revised: 10/19/2021] [Accepted: 10/19/2021] [Indexed: 11/25/2022]
Abstract
Since Nicolle, Manceaux and Splendore first described Toxoplasma gondii as a parasite of rodents and rabbits in the early 20th century, a diverse and vigorous research community has been built around studying this fascinating intracellular parasite. In addition to its importance as a pathogen of humans, livestock and wildlife, modern researchers are attracted to T. gondii as a facile experimental system to study many aspects of evolutionary biology, cellular biology, host-microbe interactions, and host immunity. For new researchers entering the field, the extensive literature describing the biology of the parasite, and the interactions with its host, can be daunting. In this review, we examine four foundational studies that describe various aspects of T. gondii biology, presenting a 'journal club'-style analysis of each. We have chosen a paper that established the beguiling life cycle of the parasite (Hutchison et al., 1971), a paper that described key features of its cellular biology that the parasite shares with related organisms (Gustafson et al., 1954), a paper that characterised the origin of the unique compartment in which the parasite resides within host cells (Jones and Hirsch, 1972), and a paper that established a key mechanism in the host immune response to parasite infection (Pfefferkorn, 1984). These interesting and far-reaching studies set the stage for subsequent research into numerous facets of parasite biology. As well as providing new researchers with an entry point into the literature surrounding the parasite, revisiting these studies can remind us of the roots of our discipline, how far we have come, and the new directions in which we might head.
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Affiliation(s)
- Melissa B Lodoen
- Institute for Immunology, University of California, Irvine, Irvine, CA, USA; Department of Molecular Biology and Biochemistry, University of California, Irvine, Irvine, California, USA
| | - Nicholas C Smith
- School of Life Sciences, University of Technology Sydney, Ultimo, NSW 2007, Australia; Research School of Biology, Australian National University, Canberra, ACT 2600, Australia
| | - Dominique Soldati-Favre
- Department of Microbiology and Molecular Medicine, CMU, University of Geneva, Geneva, Switzerland
| | - David J P Ferguson
- Nuffield Department of Clinical Laboratory Science, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK; Department of Biological and Medical Sciences, Faculty of Health and Life Science, Oxford Brookes University, Gipsy Lane, Oxford OX3 0BP, UK
| | - Giel G van Dooren
- Research School of Biology, Australian National University, Canberra, ACT 2600, Australia.
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36
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Wang ZJ, Yu SM, Gao JM, Zhang P, Hide G, Yamamoto M, Lai DH, Lun ZR. High resistance to Toxoplasma gondii infection in inducible nitric oxide synthase knockout rats. iScience 2021; 24:103280. [PMID: 34765911 PMCID: PMC8571494 DOI: 10.1016/j.isci.2021.103280] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 03/08/2021] [Accepted: 10/13/2021] [Indexed: 11/29/2022] Open
Abstract
Nitric oxide (NO) is an important immune molecule that acts against extracellular and intracellular pathogens in most hosts. However, after the knockout of inducible nitric oxide synthase (iNOS−/−) in Sprague Dawley (SD) rats, these iNOS−/− rats were found to be completely resistant to Toxoplasma gondii infection. Once the iNOS−/− rat peritoneal macrophages (PMs) were infected with T. gondii, they produced high levels of reactive oxygen species (ROS) triggered by GRA43 secreted by T. gondii, which damaged the parasitophorous vacuole membrane and PM mitochondrial membranes within a few hours post-infection. Further evidence indicated that the high levels of ROS caused mitochondrial superoxide dismutase 2 depletion and induced PM pyroptosis and cell death. This discovery of complete resistance to T. gondii infection, in the iNOS−/−-SD rat, demonstrates a strong link between NO and ROS in immunity to T. gondii infection and showcases a potentially novel and effective backup innate immunity system. iNOS−/−-SD rats show strong resistance to Toxoplasma gondii infection iNOS−/−-SD rat PMs resist T. gondii infection through ROS upregulation The T. gondii infection results in PM pyroptosis in iNOS−/−-SD rats GRAs play a key role in the activation of resistance in iNOS−/−-SD rat PMs
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Affiliation(s)
- Zhen-Jie Wang
- Guangdong Provincial Key Laboratory of Aquatic Economic Animals, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, The People's Republic of China
| | - Shao-Meng Yu
- Guangdong Provincial Key Laboratory of Aquatic Economic Animals, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, The People's Republic of China
| | - Jiang-Mei Gao
- Department of Parasitology, Key Laboratory of Tropical Disease Control of the Ministry of Education, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou 510080, The People's Republic of China
| | - Peng Zhang
- Guangdong Provincial Key Laboratory of Aquatic Economic Animals, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, The People's Republic of China
| | - Geoff Hide
- Biomedical Research Centre, School of Science, Engineering and Environment, University of Salford, Salford M5 4WT, UK
| | - Masahiro Yamamoto
- Department of Immunoparasitology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
| | - De-Hua Lai
- Guangdong Provincial Key Laboratory of Aquatic Economic Animals, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, The People's Republic of China
| | - Zhao-Rong Lun
- Guangdong Provincial Key Laboratory of Aquatic Economic Animals, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, The People's Republic of China.,Department of Parasitology, Key Laboratory of Tropical Disease Control of the Ministry of Education, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou 510080, The People's Republic of China.,Biomedical Research Centre, School of Science, Engineering and Environment, University of Salford, Salford M5 4WT, UK
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37
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Frickel EM, Hunter CA. Lessons from Toxoplasma: Host responses that mediate parasite control and the microbial effectors that subvert them. J Exp Med 2021; 218:212714. [PMID: 34670268 PMCID: PMC8532566 DOI: 10.1084/jem.20201314] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 09/03/2021] [Accepted: 09/29/2021] [Indexed: 11/15/2022] Open
Abstract
The intracellular parasite Toxoplasma gondii has long provided a tractable experimental system to investigate how the immune system deals with intracellular infections. This review highlights the advances in defining how this organism was first detected and the studies with T. gondii that contribute to our understanding of how the cytokine IFN-γ promotes control of vacuolar pathogens. In addition, the genetic tractability of this eukaryote organism has provided the foundation for studies into the diverse strategies that pathogens use to evade antimicrobial responses and now provides the opportunity to study the basis for latency. Thus, T. gondii remains a clinically relevant organism whose evolving interactions with the host immune system continue to teach lessons broadly relevant to host–pathogen interactions.
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Affiliation(s)
- Eva-Maria Frickel
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Edgbaston, UK
| | - Christopher A Hunter
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA
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38
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Dockterman J, Fee BE, Taylor GA, Coers J. Murine Irgm Paralogs Regulate Nonredundant Functions To Execute Host Defense to Toxoplasma gondii. Infect Immun 2021; 89:e0020221. [PMID: 34338548 PMCID: PMC8519265 DOI: 10.1128/iai.00202-21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Accepted: 07/16/2021] [Indexed: 12/22/2022] Open
Abstract
Gamma interferon (IFN-γ)-induced immunity-related GTPases (IRGs) confer cell-autonomous immunity to the intracellular protozoan pathogen Toxoplasma gondii. Effector IRGs are loaded onto the Toxoplasma-containing parasitophorous vacuole (PV), where they recruit ubiquitin ligases, ubiquitin-binding proteins, and IFN-γ-inducible guanylate-binding proteins (Gbps), prompting PV lysis and parasite destruction. Host cells lacking the regulatory IRGs Irgm1 and Irgm3 fail to load effector IRGs, ubiquitin, and Gbps onto the PV and are consequently defective for cell-autonomous immunity to Toxoplasma. However, the role of the third regulatory IRG, Irgm2, in cell-autonomous immunity to Toxoplasma has remained unexplored. Here, we report that Irgm2 unexpectedly plays a limited role in the targeting of effector IRGs, ubiquitin, and Gbps to the Toxoplasma PV. Instead, Irgm2 is instrumental in the decoration of PVs with γ-aminobutyric acid receptor-associated protein-like 2 (GabarapL2). Cells lacking Irgm2 are as defective for cell-autonomous host defense to Toxoplasma as pan-Irgm-/- cells lacking all three Irgm proteins, and Irgm2-/- mice succumb to Toxoplasma infections as readily as pan-Irgm-/- mice. These findings demonstrate that, relative to Irgm1 and Irgm3, Irgm2 plays a distinct but critically important role in host resistance to Toxoplasma.
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Affiliation(s)
- Jacob Dockterman
- Department of Immunology, Duke University Medical Center, Durham, North Carolina, USA
| | - Brian E. Fee
- Geriatric Research, Education, and Clinical Center, VA Health Care Center, Durham, North Carolina, USA
- Departments of Medicine, Division of Geriatrics, and Center for the Study of Aging and Human Development, Duke University Medical Center, Durham, North Carolina, USA
| | - Gregory A. Taylor
- Department of Immunology, Duke University Medical Center, Durham, North Carolina, USA
- Geriatric Research, Education, and Clinical Center, VA Health Care Center, Durham, North Carolina, USA
- Departments of Medicine, Division of Geriatrics, and Center for the Study of Aging and Human Development, Duke University Medical Center, Durham, North Carolina, USA
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina, USA
| | - Jörn Coers
- Department of Immunology, Duke University Medical Center, Durham, North Carolina, USA
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina, USA
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39
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Subauste CS. Recent Advances in the Roles of Autophagy and Autophagy Proteins in Host Cells During Toxoplasma gondii Infection and Potential Therapeutic Implications. Front Cell Dev Biol 2021; 9:673813. [PMID: 34179003 PMCID: PMC8220159 DOI: 10.3389/fcell.2021.673813] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Accepted: 04/30/2021] [Indexed: 11/29/2022] Open
Abstract
Toxoplasma gondii is an obligate intracellular protozoan that can cause encephalitis and retinitis in humans. The success of T. gondii as a pathogen depends in part on its ability to form an intracellular niche (parasitophorous vacuole) that allows protection from lysosomal degradation and parasite replication. The parasitophorous vacuole can be targeted by autophagy or by autophagosome-independent processes triggered by autophagy proteins. However, T. gondii has developed many strategies to preserve the integrity of the parasitophorous vacuole. Here, we review the interaction between T. gondii, autophagy, and autophagy proteins and expand on recent advances in the field, including the importance of autophagy in the regulation of invasion of the brain and retina by the parasite. We discuss studies that have begun to explore the potential therapeutic applications of the knowledge gained thus far.
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Affiliation(s)
- Carlos S Subauste
- Division of Infectious Diseases and HIV Medicine, Department of Medicine, Case Western Reserve University, Cleveland, OH, United States.,Department of Pathology, Case Western Reserve University, Cleveland, OH, United States
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40
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Pradipta A, Sasai M, Motani K, Ma JS, Lee Y, Kosako H, Yamamoto M. Cell-autonomous Toxoplasma killing program requires Irgm2 but not its microbe vacuolar localization. Life Sci Alliance 2021; 4:4/7/e202000960. [PMID: 34078740 PMCID: PMC8200298 DOI: 10.26508/lsa.202000960] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 05/17/2021] [Accepted: 05/20/2021] [Indexed: 01/16/2023] Open
Abstract
Interferon-inducible GTPases, such as immunity-related GTPases (IRGs) and guanylate-binding proteins (GBPs), are essential for cell-autonomous immunity against a wide variety of intracellular pathogens including Toxoplasma IRGs comprise regulatory and effector subfamily proteins. Regulatory IRGs Irgm1 and Irgm3 play important roles in anti-Toxoplasma immunity by globally controlling effector IRGs and GBPs. There is a remaining regulatory IRG, called Irgm2, which highly accumulates on parasitophorous vacuole membranes (PVMs). Very little is known about the mechanism of the unique localization on Toxoplasma PVMs. Here, we show that Irgm2 is important to control parasite killing through recruitment of Gbp1 and Irgb6, which does not require Irgm2 localization at Toxoplasma PVMs. Ubiquitination of Irgm2 in the cytosol, but not at the PVM, is also important for parasite killing through recruitment of Gbp1 to the PVM. Conversely, PVM ubiquitination and p62/Sqstm1 loading at later time points post-Toxoplasma infection require Irgm2 localization at the PVM. Irgm2-deficient mice are highly susceptible to Toxoplasma infection. Taken together, these data indicate that Irgm2 selectively controls accumulation of anti-Toxoplasma effectors to the vacuole in a manner dependent or independent on Irgm2 localization at the Toxoplasma PVM, which mediates parasite killing.
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Affiliation(s)
- Ariel Pradipta
- Department of Immunoparasitology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan.,Laboratory of Immunoparasitology, WPI Immunology Frontier Research Center, Osaka University, Osaka, Japan
| | - Miwa Sasai
- Department of Immunoparasitology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan.,Laboratory of Immunoparasitology, WPI Immunology Frontier Research Center, Osaka University, Osaka, Japan
| | - Kou Motani
- Division of Cell Signaling, Fujii Memorial Institute of Medical Sciences, Tokushima University, Tokushima, Japan
| | - Ji Su Ma
- Department of Immunoparasitology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
| | - Youngae Lee
- Laboratory of Immunoparasitology, WPI Immunology Frontier Research Center, Osaka University, Osaka, Japan
| | - Hidetaka Kosako
- Division of Cell Signaling, Fujii Memorial Institute of Medical Sciences, Tokushima University, Tokushima, Japan
| | - Masahiro Yamamoto
- Department of Immunoparasitology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan .,Laboratory of Immunoparasitology, WPI Immunology Frontier Research Center, Osaka University, Osaka, Japan.,Division of Microbiology and Immunology, Center for Infectious Disease Education and Research, Osaka University, Osaka, Japan
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Ihara F, Nishikawa Y. Toxoplasma gondii manipulates host cell signaling pathways via its secreted effector molecules. Parasitol Int 2021; 83:102368. [PMID: 33905814 DOI: 10.1016/j.parint.2021.102368] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2021] [Revised: 03/13/2021] [Accepted: 04/07/2021] [Indexed: 01/07/2023]
Abstract
The obligate intracellular parasite Toxoplasma gondii secretes a vast variety of effector molecules from organelles known as rhoptries (ROPs) and dense granules (GRAs). ROP proteins are released into the cytosol of the host cell where they are directed to the cell nucleus or to the parasitophorous vacuole (PV) membrane. ROPs secrete proteins that enable host cell penetration and vacuole formation by the parasites, as well as hijacking host-immune responses. After invading host cells, T. gondii multiplies within a PV that is maintained by the parasite proteins secreted from GRAs. Most GRA proteins remain within the PV, but some are known to access the host cytosol across the PV membrane, and a few are able to traffic into the host-cell nucleus. These effectors bind to host cell proteins and affect host cell signaling pathways to favor the parasite. Studies on host-pathogen interactions have identified many infection-altered host signal transductions. Notably, the relationship between individual parasite effector molecules and the specific targeting of host-signaling pathways is being elucidated through the advent of forward and reverse genetic strategies. Understanding the complex nature of the host-pathogen interactions underlying how the host-signaling pathway is manipulated by parasite effectors may lead to new molecular biological knowledge and novel therapeutic methods for toxoplasmosis. In this review, we discuss how T. gondii modulates cell signaling pathways in the host to favor its survival.
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Affiliation(s)
- Fumiaki Ihara
- Molecular Parasitology Section, Laboratory of Parasitic Diseases, National Institutes of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States.
| | - Yoshifumi Nishikawa
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Japan.
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42
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Elsheikha HM, Marra CM, Zhu XQ. Epidemiology, Pathophysiology, Diagnosis, and Management of Cerebral Toxoplasmosis. Clin Microbiol Rev 2021; 34:e00115-19. [PMID: 33239310 PMCID: PMC7690944 DOI: 10.1128/cmr.00115-19] [Citation(s) in RCA: 70] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Toxoplasma gondii is known to infect a considerable number of mammalian and avian species and a substantial proportion of the world's human population. The parasite has an impressive ability to disseminate within the host's body and employs various tactics to overcome the highly regulatory blood-brain barrier and reside in the brain. In healthy individuals, T. gondii infection is largely tolerated without any obvious ill effects. However, primary infection in immunosuppressed patients can result in acute cerebral or systemic disease, and reactivation of latent tissue cysts can lead to a deadly outcome. It is imperative that treatment of life-threatening toxoplasmic encephalitis is timely and effective. Several therapeutic and prophylactic regimens have been used in clinical practice. Current approaches can control infection caused by the invasive and highly proliferative tachyzoites but cannot eliminate the dormant tissue cysts. Adverse events and other limitations are associated with the standard pyrimethamine-based therapy, and effective vaccines are unavailable. In this review, the epidemiology, economic impact, pathophysiology, diagnosis, and management of cerebral toxoplasmosis are discussed, and critical areas for future research are highlighted.
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Affiliation(s)
- Hany M Elsheikha
- Faculty of Medicine and Health Sciences, School of Veterinary Medicine and Science, University of Nottingham, Loughborough, United Kingdom
| | - Christina M Marra
- Departments of Neurology and Medicine, University of Washington School of Medicine, Seattle, Washington, USA
| | - Xing-Quan Zhu
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, People's Republic of China
- College of Veterinary Medicine, Shanxi Agricultural University, Taigu, Shanxi Province, People's Republic of China
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Wu M, Cudjoe O, Shen J, Chen Y, Du J. The Host Autophagy During Toxoplasma Infection. Front Microbiol 2020; 11:589604. [PMID: 33193253 PMCID: PMC7642512 DOI: 10.3389/fmicb.2020.589604] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Accepted: 09/28/2020] [Indexed: 12/12/2022] Open
Abstract
Autophagy is an important homeostatic mechanism, in which lysosomes degrade and recycle cytosolic components. As a key defense mechanism against infections, autophagy is involved in the capture and elimination of intracellular parasites. However, intracellular parasites, such as Toxoplasma gondii, have developed several evasion mechanisms to manipulate the host cell autophagy for their growth and establish a chronic infection. This review provides an insight into the autophagy mechanism used by the host cells in the control of T. gondii and the host exploitation by the parasite. First, we summarize the mechanism of autophagy, xenophagy, and LC3-associated phagocytosis. Then, we illustrate the process of autophagy proteins-mediated T. gondii clearance. Furthermore, we discuss how the parasite blocks and exploits this process for its survival.
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Affiliation(s)
- Minmin Wu
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China.,The Key Laboratory of Zoonoses of Anhui, Anhui Medical University, Hefei, China.,The Key Laboratory of Pathogen Biology of Anhui Province, Anhui Medical University, Hefei, China
| | - Obed Cudjoe
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China.,The Key Laboratory of Zoonoses of Anhui, Anhui Medical University, Hefei, China.,The Key Laboratory of Pathogen Biology of Anhui Province, Anhui Medical University, Hefei, China
| | - Jilong Shen
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China.,The Key Laboratory of Zoonoses of Anhui, Anhui Medical University, Hefei, China.,The Key Laboratory of Pathogen Biology of Anhui Province, Anhui Medical University, Hefei, China
| | - Ying Chen
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China.,The Key Laboratory of Zoonoses of Anhui, Anhui Medical University, Hefei, China.,The Key Laboratory of Pathogen Biology of Anhui Province, Anhui Medical University, Hefei, China.,School of Nursing, Anhui Medical University, Hefei, China
| | - Jian Du
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China.,The Key Laboratory of Zoonoses of Anhui, Anhui Medical University, Hefei, China.,The Key Laboratory of Pathogen Biology of Anhui Province, Anhui Medical University, Hefei, China
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44
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Nyonda MA, Hammoudi PM, Ye S, Maire J, Marq JB, Yamamoto M, Soldati-Favre D. Toxoplasma gondii GRA60 is an effector protein that modulates host cell autonomous immunity and contributes to virulence. Cell Microbiol 2020; 23:e13278. [PMID: 33040458 DOI: 10.1111/cmi.13278] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 10/04/2020] [Accepted: 10/08/2020] [Indexed: 02/06/2023]
Abstract
Toxoplasma gondii infects virtually any nucleated cell and resides inside a non-phagocytic vacuole surrounded by a parasitophorous vacuolar membrane (PVM). Pivotal to the restriction of T. gondii dissemination upon infection in murine cells is the recruitment of immunity regulated GTPases (IRGs) and guanylate binding proteins (GBPs) to the PVM that leads to pathogen elimination. The virulent T. gondii type I RH strain secretes a handful of effectors including the dense granule protein GRA7, the serine-threonine kinases ROP17 and ROP18, and a pseudo-kinase ROP5, that synergistically inhibit the recruitment of IRGs to the PVM. Here, we characterise GRA60, a novel dense granule effector, which localises to the vacuolar space and PVM and contributes to virulence of RH in mice, suggesting a role in the subversion of host cell defence mechanisms. Members of the host cell IRG defence system Irgb10 and Irga6 are recruited to the PVM of RH parasites lacking GRA60 as observed previously for the avirulent RHΔrop5 mutant, with RH preventing such recruitment. Deletion of GRA60 in RHΔrop5 leads to a recruitment of IRGs comparable to the single knockouts. GRA60 therefore represents a novel parasite effector conferring resistance to IRGs in type I parasites, and found associated to ROP18, a member of the virulence complex.
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Affiliation(s)
- Mary Akinyi Nyonda
- Department of Microbiology and Molecular Medicine, University of Geneva, Geneva, Switzerland
| | - Pierre-Mehdi Hammoudi
- Department of Microbiology and Molecular Medicine, University of Geneva, Geneva, Switzerland
| | - Shu Ye
- Department of Microbiology and Molecular Medicine, University of Geneva, Geneva, Switzerland
| | - Jessica Maire
- Department of Microbiology and Molecular Medicine, University of Geneva, Geneva, Switzerland
| | - Jean-Baptiste Marq
- Department of Microbiology and Molecular Medicine, University of Geneva, Geneva, Switzerland
| | - Masahiro Yamamoto
- Department of Immunoparasitology, Division of Infectious Diseases, Osaka University, Suita, Japan
| | - Dominique Soldati-Favre
- Department of Microbiology and Molecular Medicine, University of Geneva, Geneva, Switzerland
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Wang Y, Sangaré LO, Paredes-Santos TC, Hassan MA, Krishnamurthy S, Furuta AM, Markus BM, Lourido S, Saeij JPJ. Genome-wide screens identify Toxoplasma gondii determinants of parasite fitness in IFNγ-activated murine macrophages. Nat Commun 2020; 11:5258. [PMID: 33067458 PMCID: PMC7567896 DOI: 10.1038/s41467-020-18991-8] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Accepted: 09/22/2020] [Indexed: 12/12/2022] Open
Abstract
Macrophages play an essential role in the early immune response against Toxoplasma and are the cell type preferentially infected by the parasite in vivo. Interferon gamma (IFNγ) elicits a variety of anti-Toxoplasma activities in macrophages. Using a genome-wide CRISPR screen we identify 353 Toxoplasma genes that determine parasite fitness in naїve or IFNγ-activated murine macrophages, seven of which are further confirmed. We show that one of these genes encodes dense granule protein GRA45, which has a chaperone-like domain, is critical for correct localization of GRAs into the PVM and secretion of GRA effectors into the host cytoplasm. Parasites lacking GRA45 are more susceptible to IFNγ-mediated growth inhibition and have reduced virulence in mice. Together, we identify and characterize an important chaperone-like GRA in Toxoplasma and provide a resource for the community to further explore the function of Toxoplasma genes that determine fitness in IFNγ-activated macrophages.
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Affiliation(s)
- Yifan Wang
- grid.27860.3b0000 0004 1936 9684Department of Pathology, Microbiology & Immunology, School of Veterinary Medicine, University of California, Davis, Davis, CA USA
| | - Lamba Omar Sangaré
- grid.27860.3b0000 0004 1936 9684Department of Pathology, Microbiology & Immunology, School of Veterinary Medicine, University of California, Davis, Davis, CA USA
| | - Tatiana C. Paredes-Santos
- grid.27860.3b0000 0004 1936 9684Department of Pathology, Microbiology & Immunology, School of Veterinary Medicine, University of California, Davis, Davis, CA USA
| | - Musa A. Hassan
- grid.4305.20000 0004 1936 7988College of Medicine and Veterinary Medicine, The University of Edinburgh, Edinburgh, UK ,grid.4305.20000 0004 1936 7988The Roslin Institute, The University of Edinburgh, Edinburgh, UK ,grid.4305.20000 0004 1936 7988Center for Tropical Livestock Health and Genetics, The University of Edinburgh, Edinburgh, UK
| | - Shruthi Krishnamurthy
- grid.27860.3b0000 0004 1936 9684Department of Pathology, Microbiology & Immunology, School of Veterinary Medicine, University of California, Davis, Davis, CA USA
| | - Anna M. Furuta
- grid.27860.3b0000 0004 1936 9684Department of Pathology, Microbiology & Immunology, School of Veterinary Medicine, University of California, Davis, Davis, CA USA
| | - Benedikt M. Markus
- grid.270301.70000 0001 2292 6283Whitehead Institute for Biomedical Research, Cambridge, MA USA ,grid.5963.9Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Sebastian Lourido
- grid.270301.70000 0001 2292 6283Whitehead Institute for Biomedical Research, Cambridge, MA USA ,grid.116068.80000 0001 2341 2786Department of Biology, Massachusetts Institute of Technology, Cambridge, MA USA
| | - Jeroen P. J. Saeij
- grid.27860.3b0000 0004 1936 9684Department of Pathology, Microbiology & Immunology, School of Veterinary Medicine, University of California, Davis, Davis, CA USA
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Mukhopadhyay D, Arranz-Solís D, Saeij JPJ. Influence of the Host and Parasite Strain on the Immune Response During Toxoplasma Infection. Front Cell Infect Microbiol 2020; 10:580425. [PMID: 33178630 PMCID: PMC7593385 DOI: 10.3389/fcimb.2020.580425] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 09/11/2020] [Indexed: 01/02/2023] Open
Abstract
Toxoplasma gondii is an exceptionally successful parasite that infects a very broad host range, including humans, across the globe. The outcome of infection differs remarkably between hosts, ranging from acute death to sterile infection. These differential disease patterns are strongly influenced by both host- and parasite-specific genetic factors. In this review, we discuss how the clinical outcome of toxoplasmosis varies between hosts and the role of different immune genes and parasite virulence factors, with a special emphasis on Toxoplasma-induced ileitis and encephalitis.
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Affiliation(s)
- Debanjan Mukhopadhyay
- Department of Pathology, Microbiology & Immunology, School of Veterinary Medicine, University of California, Davis, Davis, CA, United States
| | - David Arranz-Solís
- Department of Pathology, Microbiology & Immunology, School of Veterinary Medicine, University of California, Davis, Davis, CA, United States
| | - Jeroen P J Saeij
- Department of Pathology, Microbiology & Immunology, School of Veterinary Medicine, University of California, Davis, Davis, CA, United States
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Interferon-Inducible GTPase 1 Impedes the Dimerization of Rabies Virus Phosphoprotein and Restricts Viral Replication. J Virol 2020; 94:JVI.01203-20. [PMID: 32796066 DOI: 10.1128/jvi.01203-20] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 08/02/2020] [Indexed: 12/12/2022] Open
Abstract
Rabies, caused by rabies virus (RABV), is an ancient zoonosis and still a major public health problem for humans, especially in developing countries. RABV can be recognized by specific innate recognition receptors, resulting in the production of hundreds of interferon-stimulated genes (ISGs), which can inhibit viral replication at different stages. Interferon-inducible GTPase 1 (IIGP1) is a mouse-specific ISG and belongs to the immunity-related GTPases (IRGs) family. IIGP is reported to constrain intracellular parasite infection by disrupting the parasitophorous vacuole membrane. However, the role of IIGP1 in restricting viral replication has not been reported. In this present study, we found that IIGP1 was upregulated in cells and mouse brains upon RABV infection. Overexpression of IIGP1 limited RABV replication in cell lines and reduced viral pathogenicity in a mouse model. Consistently, deficiency of IIGP1 enhanced RABV replication in different parts of mouse brains. Furthermore, we found that IIGP1 could interact with RABV phosphoprotein (P protein). Mutation and immunoprecipitation analyses revealed that the Y128 site of P protein is critical for its interaction with IIGP1. Further study demonstrated that this interaction impeded the dimerization of P protein and thus suppressed RABV replication. Collectively, our findings for the first reveal a novel role of IIGP1 in restricting a typical neurotropic virus, RABV, which will provide fresh insight into the function of this mouse-specific ISG.IMPORTANCE Interferon and its downstream products, ISGs, are essential in defending against pathogen invasion. One of the ISGs, IIGP1, has been found to constrain intracellular parasite infection by disrupting their vacuole membranes. However, the role of IIGP1 in limiting viral infection is unclear. In this study, we show that infection with a typical neurotropic virus, RABV, can induce upregulation of IIGP1, which, in turn, suppresses RABV by interacting with its phosphoprotein (P protein) and thus blocking the dimerization of P protein. Our study provides the first evidence that IIGP1 functions in limiting viral infection and provides a basis for comprehensive understanding of this important ISG.
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48
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Song LY, Wu YZ, Pei XX, Li R, Chen HT, Sun XZ. Pulmonary toxicity and RNA sequencing analyses of mouse in response to exposure to cellulose nanofibrils. Inhal Toxicol 2020; 32:388-401. [PMID: 33043732 DOI: 10.1080/08958378.2020.1831112] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
OBJECTIVE The growing applications of nanocelluloses in the fields of advanced nanocomposites, electronics, and medical devices necessitate investigation of their potential adverse effects on human health. The lungs are the primary and the most important route for the entry of nanocelluloses into the human body in occupational settings. However, data on the pulmonary toxicity of cellulose nanofibrils (CNFs) and its molecular mechanism are limited. This study investigated the pulmonary toxicity of CNFs and its genomic expression using the RNA sequencing approach. MATERIALS AND METHODS Female C57BL/6 mice were administered CNFs at 50 μg/mouse by oropharyngeal aspiration. Samples were collected at 3 and 14 days after exposure to CNFs (DAEC). RESULTS At three DAEC, the microscopic sections of lungs revealed a significant inflammatory response. In terms of gene expression alterations, 94 genes were up-regulated, and 107 genes were down-regulated. Most of these differentially expressed genes were involved in the inflammatory and immune responses, including chemokines, NK cells, killer cell lectin-like receptors, CD antigens, T cell-specific GTPases, immunity-related GTPase family M members, and interferon-induced proteins encoding genes. However, only 9 and 26 genes at 14 DAEC were significantly up- and down-regulated, respectively. CONCLUSIONS The pathological analysis of lung sections and the analysis of sequencing data suggested that the homeostasis of mice lungs was restored at 14 DAEC. The findings of this study provide insights into the pulmonary toxicity, and underlying toxicological mechanisms, caused by exposure to CNFs, and are useful for the assessment of the potential toxicity of nanocelluloses.
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Affiliation(s)
- Li-Ying Song
- College of Engineering, Northeast Agricultural University, Harbin, China
| | - Yun-Zhou Wu
- College of Life Science, Northeast Agricultural University, Harbin, China
| | - Xi-Xiang Pei
- Harbin Botai Biological Technology Co., Ltd, Harbin, China
| | - Rui Li
- College of Engineering, Northeast Agricultural University, Harbin, China
| | - Hai-Tao Chen
- College of Engineering, Northeast Agricultural University, Harbin, China
| | - Xiao-Zheng Sun
- College of Engineering, Northeast Agricultural University, Harbin, China
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49
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Kongsomboonvech AK, Rodriguez F, Diep AL, Justice BM, Castallanos BE, Camejo A, Mukhopadhyay D, Taylor GA, Yamamoto M, Saeij JPJ, Reese ML, Jensen KDC. Naïve CD8 T cell IFNγ responses to a vacuolar antigen are regulated by an inflammasome-independent NLRP3 pathway and Toxoplasma gondii ROP5. PLoS Pathog 2020; 16:e1008327. [PMID: 32853276 PMCID: PMC7480859 DOI: 10.1371/journal.ppat.1008327] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Revised: 09/09/2020] [Accepted: 07/05/2020] [Indexed: 12/31/2022] Open
Abstract
Host resistance to Toxoplasma gondii relies on CD8 T cell IFNγ responses, which if modulated by the host or parasite could influence chronic infection and parasite transmission between hosts. Since host-parasite interactions that govern this response are not fully elucidated, we investigated requirements for eliciting naïve CD8 T cell IFNγ responses to a vacuolar resident antigen of T. gondii, TGD057. Naïve TGD057 antigen-specific CD8 T cells (T57) were isolated from transnuclear mice and responded to parasite-infected bone marrow-derived macrophages (BMDMs) in an antigen-dependent manner, first by producing IL-2 and then IFNγ. T57 IFNγ responses to TGD057 were independent of the parasite’s protein export machinery ASP5 and MYR1. Instead, host immunity pathways downstream of the regulatory Immunity-Related GTPases (IRG), including partial dependence on Guanylate-Binding Proteins, are required. Multiple T. gondii ROP5 isoforms and allele types, including ‘avirulent’ ROP5A from clade A and D parasite strains, were able to suppress CD8 T cell IFNγ responses to parasite-infected BMDMs. Phenotypic variance between clades B, C, D, F, and A strains suggest T57 IFNγ differentiation occurs independently of parasite virulence or any known IRG-ROP5 interaction. Consistent with this, removal of ROP5 is not enough to elicit maximal CD8 T cell IFNγ production to parasite-infected cells. Instead, macrophage expression of the pathogen sensors, NLRP3 and to a large extent NLRP1, were absolute requirements. Other members of the conventional inflammasome cascade are only partially required, as revealed by decreased but not abrogated T57 IFNγ responses to parasite-infected ASC, caspase-1/11, and gasdermin D deficient cells. Moreover, IFNγ production was only partially reduced in the absence of IL-12, IL-18 or IL-1R signaling. In summary, T. gondii effectors and host machinery that modulate parasitophorous vacuolar membranes, as well as NLR-dependent but inflammasome-independent pathways, determine the full commitment of CD8 T cells IFNγ responses to a vacuolar antigen. Parasites are excellent “students” of our immune system as they can deflect, antagonize and confuse the immune response making it difficult to vaccinate against these pathogens. In this report, we analyzed how a widespread parasite of mammals, Toxoplasma gondii, manipulates an immune cell needed for immunity to many intracellular pathogens, the CD8 T cell. Host pathways that govern CD8 T cell production of the immune protective cytokine, IFNγ, were also explored. We hypothesized the secreted T. gondii virulence factor, ROP5, work to inhibit the MHC 1 antigen presentation pathway therefore making it difficult for CD8 T cells to see T. gondii antigens sequestered inside a parasitophorous vacuole. However, manipulation through T. gondii ROP5 does not fully explain how CD8 T cells commit to making IFNγ in response to infection. Importantly, CD8 T cell IFNγ responses to T. gondii require the pathogen sensor NLRP3 to be expressed in the infected cell. Other proteins associated with NLRP3 activation, including members of the conventional inflammasome activation cascade pathway, are only partially involved. Our results identify a novel pathway by which NLRP3 regulates T cell function and underscore the need for NLRP3-activating adjuvants in vaccines aimed at inducing CD8 T cell IFNγ responses to parasites.
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Affiliation(s)
- Angel K. Kongsomboonvech
- Department of Molecular and Cell Biology, University of California, Merced, Merced, California, United States of America
| | - Felipe Rodriguez
- Department of Molecular and Cell Biology, University of California, Merced, Merced, California, United States of America
| | - Anh L. Diep
- Department of Molecular and Cell Biology, University of California, Merced, Merced, California, United States of America
| | - Brandon M. Justice
- Department of Molecular and Cell Biology, University of California, Merced, Merced, California, United States of America
| | - Brayan E. Castallanos
- Department of Molecular and Cell Biology, University of California, Merced, Merced, California, United States of America
| | - Ana Camejo
- Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
| | - Debanjan Mukhopadhyay
- Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California, Davis, Davis, California, United States of America
| | - Gregory A. Taylor
- Departments of Medicine; Molecular Genetics and Microbiology; and Immunology; and Center for the Study of Aging and Human Development, Duke University Medical Center, Durham, North Carolina, United States of America
- Geriatric Research, Education, and Clinical Center, Durham VA Health Care System, Durham, North Carolina, United States of America
| | - Masahiro Yamamoto
- Department of Immunoparasitology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
| | - Jeroen P. J. Saeij
- Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
- Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California, Davis, Davis, California, United States of America
| | - Michael L. Reese
- Department of Pharmacology, University of Texas, Southwestern Medical Center, Dallas, Texas, United States of America
| | - Kirk D. C. Jensen
- Department of Molecular and Cell Biology, University of California, Merced, Merced, California, United States of America
- Health Sciences Research Institute, University of California, Merced, Merced, California, United States of America
- * E-mail:
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50
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Hu S, Shi Y, Ding T, Duan W, Qiu Z, Zhao Z. Functional characterization of an immunity-related GTPase gene in immune defense from obscure puffer (Takifugu obscurus). FISH & SHELLFISH IMMUNOLOGY 2020; 103:248-255. [PMID: 32408018 DOI: 10.1016/j.fsi.2020.05.024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Revised: 04/18/2020] [Accepted: 05/09/2020] [Indexed: 06/11/2023]
Abstract
Immunity-related GTPases (IRGs) are a family of large interferon-inducible GTPases that function in effective host defense against invading pathogens. IRGs have been extensively studied in mammals for their roles in the elimination of intracellular pathogens; however, their homologs in lower vertebrates are not well known. In this study, an IRG from obscure puffer (Takifugu obscurus), ToIRG, was identified and further characterized for its functional activity. The ToIRG gene encodes a protein of 396 amino acids containing a typical N-terminal GTPase domain with three conserved motifs. Phylogenetic analysis revealed that it has a closer evolutionary relationship with mammalian GKS IRGs. Gene expression profile analysis revealed that ToIRG was ubiquitously expressed in all tested healthy tissues of obscure puffer and upregulated in response to Aeromonas hydrophila or Edwardsiella tarda challenge. The subcellular localization of ToIRG is characterized as condensed forms around the nucleus. Importantly, an antimicrobial assay in vitro suggested that ToIRG enhanced the ability of host cells to resist both intracellular (E. tarda) and extracellular pathogens (A. hydrophila). Taken together, these results provide the functional characterization of obscure puffer IRGs in immune defense, which is the first study to reveal the function of IRGs in bony fish and will provide important insights into the evolutionary divergence of IRGs.
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Affiliation(s)
- Sufei Hu
- Department of Marine Biology, College of Oceanography, Hohai University, Nanjing, 210098, China
| | - Yan Shi
- Department of Marine Biology, College of Oceanography, Hohai University, Nanjing, 210098, China.
| | - Tie Ding
- Department of Marine Biology, College of Oceanography, Hohai University, Nanjing, 210098, China
| | - Wen Duan
- Department of Marine Biology, College of Oceanography, Hohai University, Nanjing, 210098, China
| | - Ziyue Qiu
- Department of Marine Biology, College of Oceanography, Hohai University, Nanjing, 210098, China
| | - Zhe Zhao
- Department of Marine Biology, College of Oceanography, Hohai University, Nanjing, 210098, China.
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