1
|
Wang X, Qu L, Chen J, Hu K, Zhou Z, Zhang J, An Y, Zheng J. Rhoptry proteins affect the placental barrier in the context of Toxoplasma gondii infection: Signaling pathways and functions. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2024; 280:116567. [PMID: 38850700 DOI: 10.1016/j.ecoenv.2024.116567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2024] [Revised: 05/21/2024] [Accepted: 06/05/2024] [Indexed: 06/10/2024]
Abstract
Toxoplasma gondii is an opportunistic and pathogenic obligate intracellular parasitic protozoan that is widespread worldwide and can infect most warm-blooded animals, seriously endangering human health and affecting livestock production. Toxoplasmosis caused by T. gondii infection has different clinical manifestations, which are mainly determined by the virulence of T. gondii and host differences. Among the manifestations of this condition, abortion, stillbirth, and fetal malformation can occur if a woman is infected with T. gondii in early pregnancy. Here, we discuss how the T. gondii rhoptry protein affects host pregnancy outcomes and speculate on the related signaling pathways involved. The effects of rhoptry proteins of T. gondii on the placental barrier are complex. Rhoptry proteins not only regulate interferon-regulated genes (IRGs) to ensure the survival of parasites in activated cells but also promote the spread of worms in tissues and the invasive ability of the parasites. The functions of these rhoptry proteins and the associated signaling pathways highlight relevant mechanisms by which Toxoplasma crosses the placental barrier and influences fetal development and will guide future studies to uncover the complexity of the host-pathogen interactions.
Collapse
Affiliation(s)
- Xinlei Wang
- Department of Clinical Laboratory, The Second Hospital of Jilin University, Changchun, China
| | - Lai Qu
- Department of Intensive Care Unit, First Hospital of Jilin University, Changchun, China
| | - Jie Chen
- Institute of Theoretical Chemistry, Jilin University, Changchun, China
| | - Kaisong Hu
- Department of Pathogenobiology, College of Basic Medical Sciences, Jilin University, Changchun, China
| | - Zhengjie Zhou
- Department of Pathogenobiology, College of Basic Medical Sciences, Jilin University, Changchun, China
| | - Jiaqi Zhang
- Department of Pathogenobiology, College of Basic Medical Sciences, Jilin University, Changchun, China
| | - Yiming An
- Department of Pathogenobiology, College of Basic Medical Sciences, Jilin University, Changchun, China
| | - Jingtong Zheng
- Department of Pathogenobiology, College of Basic Medical Sciences, Jilin University, Changchun, China.
| |
Collapse
|
2
|
Boucher MJ, Madhani HD. Convergent evolution of innate immune-modulating effectors in invasive fungal pathogens. Trends Microbiol 2024; 32:435-447. [PMID: 37985333 DOI: 10.1016/j.tim.2023.10.011] [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: 09/29/2023] [Revised: 10/26/2023] [Accepted: 10/27/2023] [Indexed: 11/22/2023]
Abstract
Invasive fungal infections pose a major threat to human health. Bacterial and protozoan pathogens secrete protein effectors that overcome innate immune barriers to promote microbial colonization, yet few such molecules have been identified in human fungal pathogens. Recent studies have begun to reveal these long-sought effectors and have illuminated how they subvert key cellular pathways, including apoptosis, myeloid cell polarization, Toll-like receptor signaling, and phagosome action. Thus, despite lacking the specialized secretion systems of bacteria and parasites, it is increasingly clear that fungi independently evolved effectors targeting pathways often subverted by other classes of pathogens. These findings demonstrate the remarkable power of convergent evolution to enable diverse microbes to infect humans while also setting the stage for detailed dissection of fungal disease mechanisms.
Collapse
Affiliation(s)
- Michael J Boucher
- Department of Biochemistry & Biophysics, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Hiten D Madhani
- Department of Biochemistry & Biophysics, University of California, San Francisco, San Francisco, CA 94158, USA.
| |
Collapse
|
3
|
Seizova S, Ferrel A, Boothroyd J, Tonkin CJ. Toxoplasma protein export and effector function. Nat Microbiol 2024; 9:17-28. [PMID: 38172621 DOI: 10.1038/s41564-023-01563-z] [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: 03/28/2022] [Accepted: 11/16/2023] [Indexed: 01/05/2024]
Abstract
Toxoplasma gondii is a single-celled eukaryotic parasite with a considerable host range that must invade the cells of warm-blooded hosts to survive and replicate. The challenges and opportunities that such a strategy represent have been met by the evolution of effectors that are delivered into host cells, counter host defences and co-opt host cell functions for their own purposes. These effectors are delivered in two waves using distinct machinery for each. In this Review, we focus on understanding the architecture of these protein-export systems and how their protein cargo is recognized and selected. We discuss the recent findings on the role that host manipulation has in latent Toxoplasma infections. We also discuss how these recent findings compare to protein export in the related Plasmodium spp. (the causative agent of malaria) and how this can inform our understanding of host manipulation in the larger Apicomplexa phylum and its evolution.
Collapse
Affiliation(s)
- Simona Seizova
- School of Life Sciences, The University of Dundee, Dundee, UK
| | - Abel Ferrel
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford University, Stanford, CA, USA
| | - John Boothroyd
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford University, Stanford, CA, USA.
| | - Christopher J Tonkin
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia.
| |
Collapse
|
4
|
Butterworth S, Kordova K, Chandrasekaran S, Thomas KK, Torelli F, Lockyer EJ, Edwards A, Goldstone R, Koshy AA, Treeck M. High-throughput identification of Toxoplasma gondii effector proteins that target host cell transcription. Cell Host Microbe 2023; 31:1748-1762.e8. [PMID: 37827122 DOI: 10.1016/j.chom.2023.09.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 08/04/2023] [Accepted: 09/07/2023] [Indexed: 10/14/2023]
Abstract
Intracellular pathogens and other endosymbionts reprogram host cell transcription to suppress immune responses and recalibrate biosynthetic pathways. This reprogramming is critical in determining the outcome of infection or colonization. We combine pooled CRISPR knockout screening with dual host-microbe single-cell RNA sequencing, a method we term dual perturb-seq, to identify the molecular mediators of these transcriptional interactions. Applying dual perturb-seq to the intracellular pathogen Toxoplasma gondii, we are able to identify previously uncharacterized effector proteins and directly infer their function from the transcriptomic data. We show that TgGRA59 contributes to the export of other effector proteins from the parasite into the host cell and identify an effector, TgSOS1, that is necessary for sustained host STAT6 signaling and thereby contributes to parasite immune evasion and persistence. Together, this work demonstrates a tool that can be broadly adapted to interrogate host-microbe transcriptional interactions and reveal mechanisms of infection and immune evasion.
Collapse
Affiliation(s)
- Simon Butterworth
- Signalling in Apicomplexan Parasites Laboratory, The Francis Crick Institute, London NW1 1AT, UK
| | - Kristina Kordova
- Signalling in Apicomplexan Parasites Laboratory, The Francis Crick Institute, London NW1 1AT, UK
| | | | | | - Francesca Torelli
- Signalling in Apicomplexan Parasites Laboratory, The Francis Crick Institute, London NW1 1AT, UK
| | - Eloise J Lockyer
- Signalling in Apicomplexan Parasites Laboratory, The Francis Crick Institute, London NW1 1AT, UK
| | - Amelia Edwards
- Advanced Sequencing Facility, The Francis Crick Institute, London NW1 1AT, UK
| | - Robert Goldstone
- Advanced Sequencing Facility, The Francis Crick Institute, London NW1 1AT, UK
| | - Anita A Koshy
- BIO5 Institute, University of Arizona, Tucson, AZ 85719, USA; Department of Immunobiology, University of Arizona, Tucson, AZ 85719, USA; Department of Neurology, University of Arizona, Tucson, AZ 85719, USA
| | - Moritz Treeck
- Signalling in Apicomplexan Parasites Laboratory, The Francis Crick Institute, London NW1 1AT, UK; Cell Biology of Host-Pathogen Interaction Laboratory, Instituto Gulbenkian de Ciência, Oeiras 2780-156, Portugal.
| |
Collapse
|
5
|
Jin QW, Yu T, Pan M, Fan YM, Huang SY. ROP16 of Toxoplasma gondii Inhibits Innate Immunity by Triggering cGAS-STING Pathway Inactivity through the Polyubiquitination of STING. Cells 2023; 12:1862. [PMID: 37508526 PMCID: PMC10378213 DOI: 10.3390/cells12141862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Revised: 06/30/2023] [Accepted: 07/03/2023] [Indexed: 07/30/2023] Open
Abstract
cGAS-STING signaling is a major pathway in inducing type Ⅰ IFN, which plays a crucial role in the defense against T. gondii infection. In contrast, T. gondii develops multiple strategies to counteract the host defense, causing serious diseases in a wide range of hosts. Here, we demonstrate that T. gondii rhoptry protein 16 (ROP16) dampens type I interferon signaling via the inhibition of the cGAS (cyclic GMP-AMP synthase) pathway through the polyubiquitination of STING. Mechanistically, ROP16 interacts with STING through the SignalP domain and inhibits the K63-linked ubiquitination of STING in an NLS (nuclear localization signal)-domain-dependent manner. Consequently, knocking out the ROP16 in PRU tachyzoites promotes the STING-mediated production of type I IFNs and limits the replication of T. gondii. Together, these findings describe a distinct pathway where T. gondii exploits the ubiquitination of STING to evade host anti-parasite immunity, revealing new insights into the interaction between the host and parasites.
Collapse
Affiliation(s)
- Qi-Wang Jin
- Jiangsu Key Laboratory of Zoonosis, Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Institute of Comparative Medicine, College of Veterinary Medicine, Yangzhou University, Yangzhou 225009, China
| | - Ting Yu
- Jiangsu Key Laboratory of Zoonosis, Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Institute of Comparative Medicine, College of Veterinary Medicine, Yangzhou University, Yangzhou 225009, China
| | - Ming Pan
- Jiangsu Key Laboratory of Zoonosis, Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Institute of Comparative Medicine, College of Veterinary Medicine, Yangzhou University, Yangzhou 225009, China
| | - Yi-Min Fan
- Jiangsu Key Laboratory of Zoonosis, Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Institute of Comparative Medicine, College of Veterinary Medicine, Yangzhou University, Yangzhou 225009, China
| | - Si-Yang Huang
- Jiangsu Key Laboratory of Zoonosis, Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Institute of Comparative Medicine, College of Veterinary Medicine, Yangzhou University, Yangzhou 225009, China
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, The Ministry of Education of China, Yangzhou University, Yangzhou 225009, China
| |
Collapse
|
6
|
Goto Y, Mizobuchi H. Pathological roles of macrophages in Leishmania infections. Parasitol Int 2023; 94:102738. [PMID: 36738983 DOI: 10.1016/j.parint.2023.102738] [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: 10/27/2022] [Revised: 01/31/2023] [Accepted: 01/31/2023] [Indexed: 02/05/2023]
Abstract
Macrophages are the major host cells for Leishmania parasites, and determine the fate of infection by either limiting or allowing growth of the parasites, resulting in development or control of leishmaniasis, respectively. They also play important roles in causing pathological outcomes during Leishmania infection. The pathophysiology is complex and include a wide variety of molecular and cellular responses including enhancement of inflammatory responses by releasing cytokines, causing damages to surrounding cells by reactive oxygen species, or disordered phagocytosis of other cells. It is of note that disease severity in leishmaniasis sometimes does not correlate with parasite burdens, indicating that pathological roles of macrophages are not necessarily linked to their parasite-killing activities that are often defined by M1/M2 status. Here, we review the roles of macrophages in leishmaniasis with a focus on their pathological mechanisms in disease development.
Collapse
Affiliation(s)
- Yasuyuki Goto
- Laboratory of Molecular Immunology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
| | - Haruka Mizobuchi
- Laboratory of Molecular Immunology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| |
Collapse
|
7
|
Kongsomboonvech AK, García-López L, Njume F, Rodriguez F, Souza SP, Rosenberg A, Jensen KDC. Variation in CD8 T cell IFNγ differentiation to strains of Toxoplasma gondii is characterized by small effect QTLs with contribution from ROP16. Front Cell Infect Microbiol 2023; 13:1130965. [PMID: 37287466 PMCID: PMC10242045 DOI: 10.3389/fcimb.2023.1130965] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2022] [Accepted: 04/17/2023] [Indexed: 06/09/2023] Open
Abstract
Introduction Toxoplasma gondii induces a strong CD8 T cell response characterized by the secretion of IFNγ that promotes host survival during infection. The initiation of CD8 T cell IFNγ responses in vitro differs widely between clonal lineage strains of T. gondii, in which type I strains are low inducers, while types II and III strains are high inducers. We hypothesized this phenotype is due to a polymorphic "Regulator Of CD8 T cell Response" (ROCTR). Methods Therefore, we screened F1 progeny from genetic crosses between the clonal lineage strains to identify ROCTR. Naïve antigen-specific CD8 T cells (T57) isolated from transnuclear mice, which are specific for the endogenous and vacuolar TGD057 antigen, were measured for their ability to become activated, transcribe Ifng and produce IFNγ in response to T. gondii infected macrophages. Results Genetic mapping returned four non-interacting quantitative trait loci (QTL) with small effect on T. gondii chromosomes (chr) VIIb-VIII, X and XII. These loci encompass multiple gene candidates highlighted by ROP16 (chrVIIb-VIII), GRA35 (chrX), TgNSM (chrX), and a pair of uncharacterized NTPases (chrXII), whose locus we report to be significantly truncated in the type I RH background. Although none of the chromosome X and XII candidates bore evidence for regulating CD8 T cell IFNγ responses, type I variants of ROP16 lowered Ifng transcription early after T cell activation. During our search for ROCTR, we also noted the parasitophorous vacuole membrane (PVM) targeting factor for dense granules (GRAs), GRA43, repressed the response suggesting PVM-associated GRAs are important for CD8 T cell activation. Furthermore, RIPK3 expression in macrophages was an absolute requirement for CD8 T cell IFNγ differentiation implicating the necroptosis pathway in T cell immunity to T. gondii. Discussion Collectively, our data suggest that while CD8 T cell IFNγ production to T. gondii strains vary dramatically, it is not controlled by a single polymorphism with strong effect. However, early in the differentiation process, polymorphisms in ROP16 can regulate commitment of responding CD8 T cells to IFNγ production which may have bearing on immunity to T. gondii.
Collapse
Affiliation(s)
- Angel K. Kongsomboonvech
- Department of Molecular and Cell Biology, University of California, Merced, Merced, CA, United States
- Quantitative Systems Biology Graduate Program, University of California, Merced, Merced, CA, United States
| | - Laura García-López
- Department of Molecular and Cell Biology, University of California, Merced, Merced, CA, United States
- Quantitative Systems Biology Graduate Program, University of California, Merced, Merced, CA, United States
| | - Ferdinand Njume
- Department of Molecular and Cell Biology, University of California, Merced, Merced, CA, United States
| | - Felipe Rodriguez
- Department of Molecular and Cell Biology, University of California, Merced, Merced, CA, United States
| | - Scott P. Souza
- Department of Molecular and Cell Biology, University of California, Merced, Merced, CA, United States
- Quantitative Systems Biology Graduate Program, University of California, Merced, Merced, CA, United States
| | - Alex Rosenberg
- The Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, United States
| | - Kirk D. C. Jensen
- Department of Molecular and Cell Biology, University of California, Merced, Merced, CA, United States
- Health Sciences Research Institute, University of California, Merced, Merced, CA, United States
| |
Collapse
|
8
|
Panagi I, Thurston TL. Ready, STAT3, Go! Bacteria in the race for M2 macrophage polarisation. Curr Opin Microbiol 2023; 73:102285. [PMID: 36857844 DOI: 10.1016/j.mib.2023.102285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Revised: 01/20/2023] [Accepted: 01/25/2023] [Indexed: 03/03/2023]
Abstract
Despite macrophages representing professional immune cells that are integral to the host defences against microbial threats, several intracellular bacteria not only infect, but survive, replicate and often persist in these cells. This is perhaps possible because not all macrophages are the same. Instead, macrophages are loosely divided into two classes: the M1 'classically activated' pro-inflammatory subset and the M2 'alternatively activated' cells that are generally anti-inflammatory and infection-permissive. In this review, we summarise recent findings explaining how several intracellular pathogens, often using secreted effectors, rewire host circuitry in favour of an anti-inflammatory niche. A common theme is the phosphorylation and activation of the signal transducer and activator of transcription-3 (STAT3) transcription factor. We describe and compare the diverse mechanisms employed and reflect how such non-canonical processes may have evolved to circumvent regulation by the host, providing a potent means by which different pathogens manipulate the cells they infect.
Collapse
Affiliation(s)
- Ioanna Panagi
- MRC Centre for Molecular Bacteriology and Infection, Department of Infectious Disease, Imperial College London, SW7 2AZ, UK
| | - Teresa Lm Thurston
- MRC Centre for Molecular Bacteriology and Infection, Department of Infectious Disease, Imperial College London, SW7 2AZ, UK.
| |
Collapse
|
9
|
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.
Collapse
|
10
|
Effects of Ovine Monocyte-Derived Macrophage Infection by Recently Isolated Toxoplasma gondii Strains Showing Different Phenotypic Traits. Animals (Basel) 2022; 12:ani12243453. [PMID: 36552372 PMCID: PMC9774764 DOI: 10.3390/ani12243453] [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: 10/17/2022] [Revised: 11/28/2022] [Accepted: 12/02/2022] [Indexed: 12/14/2022] Open
Abstract
Ovine toxoplasmosis is one the most relevant reproductive diseases in sheep. The genetic variability among different Toxoplasma gondii isolates is known to be related to different degrees of virulence in mice and humans, but little is known regarding its potential effects in sheep. The aim of this study was to investigate the effect of genetic variability (types II (ToxoDB #1 and #3) and III (#2)) of six recently isolated strains that showed different phenotypic traits both in a normalized mouse model and in ovine trophoblasts, in ovine monocyte-derived macrophages and the subsequent transcript expression of cytokines and iNOS (inducible nitric oxide synthase). The type III isolate (TgShSp24) showed the highest rate of internalization, followed by the type II clonal isolate (TgShSp2), while the type II PRU isolates (TgShSp1, TgShSp3, TgShSp11 and TgShSp16) showed the lowest rates. The type II PRU strains, isolated from abortions, exhibited higher levels of anti-inflammatory cytokines and iNOS than those obtained from the myocardium of chronically infected sheep (type II PRU strains and type III), which had higher levels of pro-inflammatory cytokines. The present results show the existence of significant intra- and inter-genotypic differences in the parasite-macrophage relationship that need to be confirmed in in vivo experiments.
Collapse
|
11
|
Ma Z, Li Z, Jiang R, Li X, Yan K, Zhang N, Lu B, Huang Y, Dibo N, Wu X. Virulence-related gene wx2 of Toxoplasma gondii regulated host immune response via classic pyroptosis pathway. Parasit Vectors 2022; 15:454. [PMID: 36471417 PMCID: PMC9724370 DOI: 10.1186/s13071-022-05502-5] [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: 08/02/2022] [Accepted: 09/16/2022] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Toxoplasma gondii is known as the most successful parasite, which can regulate the host immune response through a variety of ways to achieve immune escape. We previously reported that a novel gene wx2 of T. gondii may be a virulence-related molecule. The objective of this study was to explore the mechanism of wx2 regulating host immune response. METHODS The wx2 knockout strain (RHwx2-/- strain) and complementary strain (RHwx2+/+ strain) were constructed by the CRISPR/Cas9 technique, and the virulence of the wx2 gene was detected and changes in pyroptosis-related molecules were observed. RESULTS Compared with the wild RH and RHwx2+/+ strain groups, the survival time for mice infected with the RHwx2-/- strain was prolonged to a certain extent. The mRNA levels of pyroptosis-related molecules of caspase-1, NLRP3, and GSDMD and et al. in mouse lymphocytes in vivo and RAW267.4 cells in vitro infected with RHwx2-/- strain increased to different degrees, compared with infected with wild RH strain and RHwx2+/+ strain. As with the mRNA level, the protein level of caspase-1, caspase-1 p20, IL-1β, NLRP3, GSDMD-FL, GSDMD-N, and phosphorylation level of NF-κB (p65) were also significantly increased. These data suggest that wx2 may regulate the host immune response through the pyroptosis pathway. In infected RAW264.7 cells at 48 h post-infection, the levels of Th1-type cytokines of IFN-γ, Th2-type cytokines such as IL-13, Th17-type cytokine of IL-17 in cells infected with RHwx2-/- were significantly higher than those of RH and RHwx2+/+ strains, suggesting that the wx2 may inhibit the host's immune response. CONCLUSION wx2 is a virulence related gene of T. gondii, and may be involved in host immune regulation by inhibiting the pyroptosis pathway.
Collapse
Affiliation(s)
- Zhenrong Ma
- grid.216417.70000 0001 0379 7164Department of Parasitology, Xiangya School of Basic Medicine, Central South University, Changsha, China
| | - Zhuolin Li
- grid.216417.70000 0001 0379 7164Department of Parasitology, Xiangya School of Basic Medicine, Central South University, Changsha, China
| | - Ruolan Jiang
- grid.216417.70000 0001 0379 7164Department of Parasitology, Xiangya School of Basic Medicine, Central South University, Changsha, China ,grid.284723.80000 0000 8877 7471School of Public Health, Southern Medical University, Guangzhou, China
| | - Xuanwu Li
- grid.216417.70000 0001 0379 7164Department of Parasitology, Xiangya School of Basic Medicine, Central South University, Changsha, China
| | - Kang Yan
- grid.216417.70000 0001 0379 7164Department of Parasitology, Xiangya School of Basic Medicine, Central South University, Changsha, China
| | - Ni Zhang
- grid.216417.70000 0001 0379 7164Department of Parasitology, Xiangya School of Basic Medicine, Central South University, Changsha, China
| | - Bin Lu
- grid.216417.70000 0001 0379 7164Department of Parasitology, Xiangya School of Basic Medicine, Central South University, Changsha, China
| | - Yehong Huang
- grid.216417.70000 0001 0379 7164Department of Parasitology, Xiangya School of Basic Medicine, Central South University, Changsha, China
| | - Nouhoum Dibo
- grid.216417.70000 0001 0379 7164Department of Parasitology, Xiangya School of Basic Medicine, Central South University, Changsha, China
| | - Xiang Wu
- grid.216417.70000 0001 0379 7164Department of Parasitology, Xiangya School of Basic Medicine, Central South University, Changsha, China ,Hunan Provincial Key Lab of Immunology and Transmission Control On Schistosomiasis, Changsha, China
| |
Collapse
|
12
|
Zhang Y, Li D, Lu S, Zheng B. Toxoplasmosis vaccines: what we have and where to go? NPJ Vaccines 2022; 7:131. [PMID: 36310233 PMCID: PMC9618413 DOI: 10.1038/s41541-022-00563-0] [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] [Received: 07/02/2022] [Accepted: 10/17/2022] [Indexed: 11/16/2022] Open
Abstract
Despite recent major advances in developing effective vaccines against toxoplasmosis, finding new protective vaccination strategies remains a challenging and elusive goal as it is critical to prevent the disease. Over the past few years, various experimental approaches have shown that developing an effective vaccine against T. gondii is achievable. However, more remains unknown due to its complicated life cycle, difficulties in clinical translation, and lack of a standardized platform. This minireview summarizes the recent advances in the development of T. gondii vaccines and the main obstacles to developing a safe, effective and durable T. gondii vaccine. The successes and failures in developing and testing vaccine candidates for the T. gondii vaccine are also discussed, which may facilitate the future development of T. gondii vaccines.
Collapse
Affiliation(s)
- Yizhuo Zhang
- grid.506977.a0000 0004 1757 7957Institute of Parasitic Diseases, School of Basic Medicine and Forensics, Hangzhou Medical College, Hangzhou, China ,grid.506977.a0000 0004 1757 7957Engineering Research Center of Novel Vaccine of Zhejiang Province, Hangzhou Medical College, Hangzhou, China
| | - Dan Li
- grid.506977.a0000 0004 1757 7957Institute of Parasitic Diseases, School of Basic Medicine and Forensics, Hangzhou Medical College, Hangzhou, China ,grid.506977.a0000 0004 1757 7957Engineering Research Center of Novel Vaccine of Zhejiang Province, Hangzhou Medical College, Hangzhou, China
| | - Shaohong Lu
- grid.506977.a0000 0004 1757 7957Institute of Parasitic Diseases, School of Basic Medicine and Forensics, Hangzhou Medical College, Hangzhou, China ,grid.506977.a0000 0004 1757 7957Engineering Research Center of Novel Vaccine of Zhejiang Province, Hangzhou Medical College, Hangzhou, China ,grid.506977.a0000 0004 1757 7957Key Laboratory of Bio-tech Vaccine of Zhejiang Province, Hangzhou Medical College, Hangzhou, China
| | - Bin Zheng
- grid.506977.a0000 0004 1757 7957Institute of Parasitic Diseases, School of Basic Medicine and Forensics, Hangzhou Medical College, Hangzhou, China ,grid.506977.a0000 0004 1757 7957Engineering Research Center of Novel Vaccine of Zhejiang Province, Hangzhou Medical College, Hangzhou, China ,grid.506977.a0000 0004 1757 7957Key Laboratory of Bio-tech Vaccine of Zhejiang Province, Hangzhou Medical College, Hangzhou, China
| |
Collapse
|
13
|
Sardinha-Silva A, Alves-Ferreira EVC, Grigg ME. Intestinal immune responses to commensal and pathogenic protozoa. Front Immunol 2022; 13:963723. [PMID: 36211380 PMCID: PMC9533738 DOI: 10.3389/fimmu.2022.963723] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Accepted: 08/15/2022] [Indexed: 11/17/2022] Open
Abstract
The physical barrier of the intestine and associated mucosal immunity maintains a delicate homeostatic balance between the host and the external environment by regulating immune responses to commensals, as well as functioning as the first line of defense against pathogenic microorganisms. Understanding the orchestration and characteristics of the intestinal mucosal immune response during commensal or pathological conditions may provide novel insights into the mechanisms underlying microbe-induced immunological tolerance, protection, and/or pathogenesis. Over the last decade, our knowledge about the interface between the host intestinal mucosa and the gut microbiome has been dominated by studies focused on bacterial communities, helminth parasites, and intestinal viruses. In contrast, specifically how commensal and pathogenic protozoa regulate intestinal immunity is less well studied. In this review, we provide an overview of mucosal immune responses induced by intestinal protozoa, with a major focus on the role of different cell types and immune mediators triggered by commensal (Blastocystis spp. and Tritrichomonas spp.) and pathogenic (Toxoplasma gondii, Giardia intestinalis, Cryptosporidium parvum) protozoa. We will discuss how these various protozoa modulate innate and adaptive immune responses induced in experimental models of infection that benefit or harm the host.
Collapse
|
14
|
Bai R, Li Y, Jian L, Yang Y, Zhao L, Wei M. The hypoxia-driven crosstalk between tumor and tumor-associated macrophages: mechanisms and clinical treatment strategies. Mol Cancer 2022; 21:177. [PMID: 36071472 PMCID: PMC9454207 DOI: 10.1186/s12943-022-01645-2] [Citation(s) in RCA: 69] [Impact Index Per Article: 34.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2022] [Accepted: 08/25/2022] [Indexed: 02/08/2023] Open
Abstract
Given that hypoxia is a persistent physiological feature of many different solid tumors and a key driver for cancer malignancy, it is thought to be a major target in cancer treatment recently. Tumor-associated macrophages (TAMs) are the most abundant immune cells in the tumor microenvironment (TME), which have a large impact on tumor development and immunotherapy. TAMs massively accumulate within hypoxic tumor regions. TAMs and hypoxia represent a deadly combination because hypoxia has been suggested to induce a pro-tumorigenic macrophage phenotype. Hypoxia not only directly affects macrophage polarization, but it also has an indirect effect by altering the communication between tumor cells and macrophages. For example, hypoxia can influence the expression of chemokines and exosomes, both of which have profound impacts on the recipient cells. Recently, it has been demonstrated that the intricate interaction between cancer cells and TAMs in the hypoxic TME is relevant to poor prognosis and increased tumor malignancy. However, there are no comprehensive literature reviews on the molecular mechanisms underlying the hypoxia-mediated communication between tumor cells and TAMs. Therefore, this review has the aim to collect all recently available data on this topic and provide insights for developing novel therapeutic strategies for reducing the effects of hypoxia.
Collapse
Affiliation(s)
- Ruixue Bai
- Department of Pharmacology, School of Pharmacy, China Medical University, Shenyang, 110122, People's Republic of China.,Liaoning Key Laboratory of Molecular Targeted Anti-Tumor Drug Development and Evaluation, China Medical University, Shenyang, 110122, People's Republic of China.,Department of Pharmacy, Shengjing Hospital of China Medical University, Shenyang, 110004, People's Republic of China
| | - Yunong Li
- Department of Pharmacology, School of Pharmacy, China Medical University, Shenyang, 110122, People's Republic of China.,Liaoning Key Laboratory of Molecular Targeted Anti-Tumor Drug Development and Evaluation, China Medical University, Shenyang, 110122, People's Republic of China
| | - Lingyan Jian
- Department of Pharmacy, Shengjing Hospital of China Medical University, Shenyang, 110004, People's Republic of China
| | - Yuehui Yang
- Department of Pharmacy, Shengjing Hospital of China Medical University, Shenyang, 110004, People's Republic of China
| | - Lin Zhao
- Department of Pharmacology, School of Pharmacy, China Medical University, Shenyang, 110122, People's Republic of China. .,Liaoning Key Laboratory of Molecular Targeted Anti-Tumor Drug Development and Evaluation, China Medical University, Shenyang, 110122, People's Republic of China.
| | - Minjie Wei
- Department of Pharmacology, School of Pharmacy, China Medical University, Shenyang, 110122, People's Republic of China. .,Liaoning Key Laboratory of Molecular Targeted Anti-Tumor Drug Development and Evaluation, China Medical University, Shenyang, 110122, People's Republic of China. .,Shenyang Kangwei Medical Laboratory Analysis Co. LTD, Shenyang, 110000, People's Republic of China.
| |
Collapse
|
15
|
Cova MM, Lamarque MH, Lebrun M. How Apicomplexa Parasites Secrete and Build Their Invasion Machinery. Annu Rev Microbiol 2022; 76:619-640. [PMID: 35671531 DOI: 10.1146/annurev-micro-041320-021425] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Apicomplexa are obligatory intracellular parasites that sense and actively invade host cells. Invasion is a conserved process that relies on the timely and spatially controlled exocytosis of unique specialized secretory organelles termed micronemes and rhoptries. Microneme exocytosis starts first and likely controls the intricate mechanism of rhoptry secretion. To assemble the invasion machinery, micronemal proteins-associated with the surface of the parasite-interact and form complexes with rhoptry proteins, which in turn are targeted into the host cell. This review covers the molecular advances regarding microneme and rhoptry exocytosis and focuses on how the proteins discharged from these two compartments work in synergy to drive a successful invasion event. Particular emphasis is given to the structure and molecular components of the rhoptry secretion apparatus, and to the current conceptual framework of rhoptry exocytosis that may constitute an unconventional eukaryotic secretory machinery closely related to the one described in ciliates. Expected final online publication date for the Annual Review of Microbiology, Volume 76 is September 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
Collapse
Affiliation(s)
- Marta Mendonça Cova
- Laboratory of Pathogen Host Interactions (LPHI), CNRS, University of Montpellier, Montpellier, France;
| | - Mauld H Lamarque
- Laboratory of Pathogen Host Interactions (LPHI), CNRS, University of Montpellier, Montpellier, France;
| | - Maryse Lebrun
- Laboratory of Pathogen Host Interactions (LPHI), CNRS, University of Montpellier, Montpellier, France;
| |
Collapse
|
16
|
Nagai K, Goto Y. Parasitomimetics: Can We Utilize Parasite-Derived Immunomodulatory Molecules for Interventions to Immunological Disorders? Front Immunol 2022; 13:824695. [PMID: 35386686 PMCID: PMC8977410 DOI: 10.3389/fimmu.2022.824695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Accepted: 02/28/2022] [Indexed: 11/17/2022] Open
Abstract
Because our immune system has ability to expel microorganisms invading our body, parasites need evolution to maintain their symbiosis with the hosts. One such strategy of the parasites is to manipulate host immunity by producing immunomodulatory molecules and the ability of parasites to regulate host immunity has long been a target of research. Parasites can not only manipulate host immune response specific to them, but also influence the host's entire immune system. Such ability of the parasites may sometimes bring benefit to the hosts as many studies have indicated the "hygiene hypothesis" that a decreased opportunity of parasitic infections is associated with an increased incidence of allergy and autoimmune diseases. In other words, elucidating the mechanisms of parasites to regulate host immunity could be applied not only to resolution of parasitic infections but also to treatment of non-parasitic immunological disorders. In this review, we show how much progress has been made in the research on immunomodulation of host immunity by parasites. Here, we define the word 'parasitomimetics' as emulation of parasites' immunomodulatory systems to solve immunological problems in humans and discuss potential applications of parasite-derived molecules to other diseases.
Collapse
Affiliation(s)
| | - Yasuyuki Goto
- Laboratory of Molecular Immunology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| |
Collapse
|
17
|
Jiang D, Wu S, Xu L, Xie G, Li D, Peng H. Anti-infection roles of miR-155-5p packaged in exosomes secreted by dendritic cells infected with Toxoplasma gondii. Parasit Vectors 2022; 15:3. [PMID: 34986898 PMCID: PMC8731220 DOI: 10.1186/s13071-021-05003-x] [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: 03/02/2021] [Accepted: 09/08/2021] [Indexed: 02/08/2023] Open
Abstract
Background Toxoplasma gondii is a zoonotic intracellular protozoon that is estimated to infect about 30% of the world’s population, resulting in toxoplasmosis in immunocompromised patients and adverse outcomes in cases of primary infection during pregnancy. Exosomes are tubular vesicles secreted by cells, and function in intercellular communication. It has been reported that the exosomes secreted by T. gondii-infected immune cells transmit infection signals to the uninfected cells. However, the mechanism and effect of the exosome transmission are still vague. We therefore investigated the function of the exosomes transmitted from DC2.4 cells infected with the T. gondii RH strain (Tg-DC-Exo) to the uninfected cells, as well as their roles in anti-infection. Methods We conducted exosome isolation and identification with ultracentrifugation, transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA), and western blot (WB) analysis. Exosome uptake by recipient cells was identified by PKH67 assay. The signal transmission and the abundance of miR-155-5p were determined using transwell assay and qRT-PCR. For detection of immune responses, cytokine secretion was evaluated. The T. gondii B1 gene was determined to evaluate tachyzoite proliferation. Results We observed that Toxoplasma infection upregulated miR-155-5p expression in DC2.4 cell-secreted exosomes, and those exosomes could be ingested by murine macrophage RAW264.7 cells. Tg-DC-Exo and miR-155-5p stimulated host proinflammatory immune responses including increased production of proinflammatory cytokines IL-6 and TNF-α, and proinflammatory marker-inducible nitric oxide synthase (iNOS). The NF-κB pathway was activated by downregulation of SOCS1, leading to inhibition of T. gondii tachyzoite proliferation in RAW264.7 cells. Conclusions Our findings provide a novel mechanism for how infected cells transmit infection signals to the uninfected cells through exosome secretion after T. gondii infection, followed by inflammatory responses and anti-infection reactions, which may help us develop a new strategy for toxoplasmosis prevention, especially in immunocompromised patients. Graphical Abstract ![]()
Supplementary Information The online version contains supplementary material available at 10.1186/s13071-021-05003-x.
Collapse
Affiliation(s)
- Dan Jiang
- Department of Pathogen Biology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515, Guangdong Province, China
| | - Shuizhen Wu
- Department of Pathogen Biology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515, Guangdong Province, China
| | - Liqing Xu
- Department of Pathogen Biology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515, Guangdong Province, China
| | - Guantai Xie
- Department of Pathogen Biology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515, Guangdong Province, China
| | - Dongliang Li
- Department of Pathogen Biology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515, Guangdong Province, China
| | - Hongjuan Peng
- Department of Pathogen Biology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515, Guangdong Province, China.
| |
Collapse
|
18
|
Hajj RE, Tawk L, Itani S, Hamie M, Ezzeddine J, El Sabban M, El Hajj H. Toxoplasmosis: Current and Emerging Parasite Druggable Targets. Microorganisms 2021; 9:microorganisms9122531. [PMID: 34946133 PMCID: PMC8707595 DOI: 10.3390/microorganisms9122531] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 11/10/2021] [Accepted: 11/10/2021] [Indexed: 12/19/2022] Open
Abstract
Toxoplasmosis is a prevalent disease affecting a wide range of hosts including approximately one-third of the human population. It is caused by the sporozoan parasite Toxoplasma gondii (T. gondii), which instigates a range of symptoms, manifesting as acute and chronic forms and varying from ocular to deleterious congenital or neuro-toxoplasmosis. Toxoplasmosis may cause serious health problems in fetuses, newborns, and immunocompromised patients. Recently, associations between toxoplasmosis and various neuropathies and different types of cancer were documented. In the veterinary sector, toxoplasmosis results in recurring abortions, leading to significant economic losses. Treatment of toxoplasmosis remains intricate and encompasses general antiparasitic and antibacterial drugs. The efficacy of these drugs is hindered by intolerance, side effects, and emergence of parasite resistance. Furthermore, all currently used drugs in the clinic target acute toxoplasmosis, with no or little effect on the chronic form. In this review, we will provide a comprehensive overview on the currently used and emergent drugs and their respective parasitic targets to combat toxoplasmosis. We will also abridge the repurposing of certain drugs, their targets, and highlight future druggable targets to enhance the therapeutic efficacy against toxoplasmosis, hence lessening its burden and potentially alleviating the complications of its associated diseases.
Collapse
Affiliation(s)
- Rana El Hajj
- Department of Biological Sciences, Beirut Arab University, P.O. Box 11-5020, Riad El Solh, Beirut 1107 2809, Lebanon;
| | - Lina Tawk
- Department of Medical Laboratory Sciences, Faculty of Health Sciences, University of Balamand, Beirut 1100 2807, Lebanon; (L.T.); (J.E.)
| | - Shaymaa Itani
- Department of Experimental Pathology, Microbiology and Immunology, Faculty of Medicine, American University of Beirut, P.O. Box 11-0236, Riad El-Solh, Beirut 1107 2020, Lebanon; (S.I.); (M.H.)
| | - Maguy Hamie
- Department of Experimental Pathology, Microbiology and Immunology, Faculty of Medicine, American University of Beirut, P.O. Box 11-0236, Riad El-Solh, Beirut 1107 2020, Lebanon; (S.I.); (M.H.)
| | - Jana Ezzeddine
- Department of Medical Laboratory Sciences, Faculty of Health Sciences, University of Balamand, Beirut 1100 2807, Lebanon; (L.T.); (J.E.)
| | - Marwan El Sabban
- Department of Anatomy, Cell Biology and Physiological Sciences, Faculty of Medicine, American University of Beirut, P.O. Box 11-0236, Riad El-Solh, Beirut 1107 2020, Lebanon;
| | - Hiba El Hajj
- Department of Experimental Pathology, Microbiology and Immunology, Faculty of Medicine, American University of Beirut, P.O. Box 11-0236, Riad El-Solh, Beirut 1107 2020, Lebanon; (S.I.); (M.H.)
- Correspondence: ; Tel.: +961–1-350000 (ext. 4897)
| |
Collapse
|
19
|
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: 37] [Impact Index Per Article: 12.3] [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.
Collapse
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
| |
Collapse
|
20
|
Matta SK, Rinkenberger N, Dunay IR, Sibley LD. Toxoplasma gondii infection and its implications within the central nervous system. Nat Rev Microbiol 2021; 19:467-480. [PMID: 33627834 DOI: 10.1038/s41579-021-00518-7] [Citation(s) in RCA: 98] [Impact Index Per Article: 32.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/19/2021] [Indexed: 01/31/2023]
Abstract
Toxoplasma gondii is a parasite that infects a wide range of animals and causes zoonotic infections in humans. Although it normally only results in mild illness in healthy individuals, toxoplasmosis is a common opportunistic infection with high mortality in individuals who are immunocompromised, most commonly due to reactivation of infection in the central nervous system. In the acute phase of infection, interferon-dependent immune responses control rapid parasite expansion and mitigate acute disease symptoms. However, after dissemination the parasite differentiates into semi-dormant cysts that form within muscle cells and neurons, where they persist for life in the infected host. Control of infection in the central nervous system, a compartment of immune privilege, relies on modified immune responses that aim to balance infection control while limiting potential damage due to inflammation. In response to the activation of interferon-mediated pathways, the parasite deploys an array of effector proteins to escape immune clearance and ensure latent survival. Although these pathways are best studied in the laboratory mouse, emerging evidence points to unique mechanisms of control in human toxoplasmosis. In this Review, we explore some of these recent findings that extend our understanding for proliferation, establishment and control of toxoplasmosis in humans.
Collapse
Affiliation(s)
- Sumit K Matta
- Department of Molecular Microbiology, School of Medicine, Washington University in St. Louis, St. Louis, MO, USA
| | - Nicholas Rinkenberger
- Department of Molecular Microbiology, School of Medicine, Washington University in St. Louis, St. Louis, MO, USA
| | - Ildiko R Dunay
- Institute of Inflammation and Neurodegeneration, Otto-von-Guericke University Magdeburg, Magdeburg, Germany
| | - L David Sibley
- Department of Molecular Microbiology, School of Medicine, Washington University in St. Louis, St. Louis, MO, USA.
| |
Collapse
|
21
|
Walters HA, Temesvari LA. Target acquired: transcriptional regulators as drug targets for protozoan parasites. Int J Parasitol 2021; 51:599-611. [PMID: 33722681 PMCID: PMC8169582 DOI: 10.1016/j.ijpara.2020.12.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 12/09/2020] [Accepted: 12/17/2020] [Indexed: 11/22/2022]
Abstract
Protozoan parasites are single-celled eukaryotic organisms that cause significant human disease and pose a substantial health and socioeconomic burden worldwide. They are responsible for at least 1 million deaths annually. The treatment of such diseases is hindered by the ability of parasites to form latent cysts, develop drug resistance, or be transmitted by insect vectors. Additionally, these pathogens have developed complex mechanisms to alter host gene expression. The prevalence of these diseases is predicted to increase as climate change leads to the augmentation of ambient temperatures, insect ranges, and warm water reservoirs. Therefore, the discovery of novel treatments is necessary. Transcription factors lie at the junction of multiple signalling pathways in eukaryotes and aberrant transcription factor function contributes to the progression of numerous human diseases including cancer, diabetes, inflammatory disorders and cardiovascular disease. Transcription factors were previously thought to be undruggable. However, due to recent advances, transcription factors now represent appealing drug targets. It is conceivable that transcription factors, and the pathways they regulate, may also serve as targets for anti-parasitic drug design. Here, we review transcription factors and transcriptional modulators of protozoan parasites, and discuss how they may be useful in drug discovery. We also provide information on transcription factors that play a role in stage conversion of parasites, TATA box-binding proteins, and transcription factors and cofactors that participate with RNA polymerases I, II and III. We also highlight a significant gap in knowledge in that the transcription factors of some of parasites have been under-investigated. Understanding parasite transcriptional pathways and how parasites alter host gene expression will be essential in discovering innovative drug targets.
Collapse
Affiliation(s)
- H A Walters
- Department of Biological Sciences, Clemson University, Clemson, SC 29634, United States; Eukaryotic Pathogens Innovation Center, Clemson University, Clemson, SC 29634, United States
| | - L A Temesvari
- Department of Biological Sciences, Clemson University, Clemson, SC 29634, United States; Eukaryotic Pathogens Innovation Center, Clemson University, Clemson, SC 29634, United States.
| |
Collapse
|
22
|
Sparvoli D, Lebrun M. Unraveling the Elusive Rhoptry Exocytic Mechanism of Apicomplexa. Trends Parasitol 2021; 37:622-637. [PMID: 34045149 DOI: 10.1016/j.pt.2021.04.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 04/19/2021] [Accepted: 04/19/2021] [Indexed: 12/11/2022]
Abstract
Apicomplexan parasites are unicellular eukaryotes that invade the cells in which they proliferate. The development of genetic tools in Toxoplasma, and then in Plasmodium, in the 1990s allowed the first description of the molecular machinery used for motility and invasion, revealing a crucial role for two different secretory organelles, micronemes and rhoptries. Rhoptry proteins are injected directly into the host cytoplasm not only to promote invasion but also to manipulate host functions. Nonetheless, the injection machinery has remained mysterious, a major conundrum in the field. Here we review recent progress in uncovering structural components and proteins implicated in rhoptry exocytosis and explain how revisiting early findings and considering the evolutionary origins of Apicomplexa contributed to some of these discoveries.
Collapse
Affiliation(s)
- Daniela Sparvoli
- LPHI UMR5235, Univ Montpellier, CNRS, F-34095 Montpellier, France
| | - Maryse Lebrun
- LPHI UMR5235, Univ Montpellier, CNRS, F-34095 Montpellier, France.
| |
Collapse
|
23
|
Clark JT, Christian DA, Gullicksrud JA, Perry JA, Park J, Jacquet M, Tarrant JC, Radaelli E, Silver J, Hunter CA. IL-33 promotes innate lymphoid cell-dependent IFN-γ production required for innate immunity to Toxoplasma gondii. eLife 2021; 10:e65614. [PMID: 33929319 PMCID: PMC8121546 DOI: 10.7554/elife.65614] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 04/29/2021] [Indexed: 12/29/2022] Open
Abstract
IL-33 is an alarmin required for resistance to the parasite Toxoplasma gondii, but its role in innate resistance to this organism is unclear. Infection with T. gondii promotes increased stromal cell expression of IL-33, and levels of parasite replication correlate with release of IL-33 in affected tissues. In response to infection, a subset of innate lymphoid cells (ILC) emerges composed of IL-33R+ NK cells and ILC1s. In Rag1-/-mice, where NK cells and ILC1 production of IFN-γ mediate innate resistance to T. gondii, the loss of the IL-33R resulted in reduced ILC responses and increased parasite replication. Furthermore, administration of IL-33 to Rag1-/- mice resulted in a marked decrease in parasite burden, increased production of IFN-γ, and the recruitment and expansion of inflammatory monocytes associated with parasite control. These protective effects of exogenous IL-33 were dependent on endogenous IL-12p40 and the ability of IL-33 to enhance ILC production of IFN-γ. These results highlight that IL-33 synergizes with IL-12 to promote ILC-mediated resistance to T. gondii.
Collapse
Affiliation(s)
- Joseph T Clark
- Department of Pathobiology, University of Pennsylvania School of Veterinary MedicinePhiladelphiaUnited States
| | - David A Christian
- Department of Pathobiology, University of Pennsylvania School of Veterinary MedicinePhiladelphiaUnited States
| | - Jodi A Gullicksrud
- Department of Pathobiology, University of Pennsylvania School of Veterinary MedicinePhiladelphiaUnited States
| | - Joseph A Perry
- Department of Pathobiology, University of Pennsylvania School of Veterinary MedicinePhiladelphiaUnited States
| | - Jeongho Park
- Department of Pathobiology, University of Pennsylvania School of Veterinary MedicinePhiladelphiaUnited States
- Kangwon National University College of Veterinary Medicine and Institute of Veterinary ScienceChuncheonRepublic of Korea
| | - Maxime Jacquet
- Department of Pathobiology, University of Pennsylvania School of Veterinary MedicinePhiladelphiaUnited States
- Liver Immunology, Department of Biomedicine, University Hospital of Basel and University of BaselBaselSwitzerland
| | - James C Tarrant
- Department of Pathobiology, University of Pennsylvania School of Veterinary MedicinePhiladelphiaUnited States
| | - Enrico Radaelli
- Department of Pathobiology, University of Pennsylvania School of Veterinary MedicinePhiladelphiaUnited States
| | - Jonathan Silver
- Department of Respiratory Inflammation and Autoimmunity, AstraZenecaGaithersburgUnited States
| | - Christopher A Hunter
- Department of Pathobiology, University of Pennsylvania School of Veterinary MedicinePhiladelphiaUnited States
| |
Collapse
|
24
|
Xu J, Zhang J, Zhang Z, Gao Z, Qi Y, Qiu W, Pan Z, Guo Q, Li B, Zhao S, Guo X, Qian M, Chen Z, Wang S, Gao X, Zhang S, Wang H, Guo X, Zhang P, Zhao R, Xue H, Li G. Hypoxic glioma-derived exosomes promote M2-like macrophage polarization by enhancing autophagy induction. Cell Death Dis 2021; 12:373. [PMID: 33828078 PMCID: PMC8026615 DOI: 10.1038/s41419-021-03664-1] [Citation(s) in RCA: 95] [Impact Index Per Article: 31.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 03/12/2021] [Accepted: 03/15/2021] [Indexed: 02/07/2023]
Abstract
Exosomes participate in intercellular communication and glioma microenvironment modulation, but the exact mechanisms by which glioma-derived exosomes (GDEs) promote the generation of the immunosuppressive microenvironment are still unclear. Here, we investigated the effects of GDEs on autophagy, the polarization of tumor-associated macrophages (TAMs), and glioma progression. Compared with normoxic glioma-derived exosomes (N-GDEs), hypoxic glioma-derived exosomes (H-GDEs) markedly facilitated autophagy and M2-like macrophage polarization, which subsequently promoted glioma proliferation and migration in vitro and in vivo. Western blot and qRT-PCR analyses indicated that interleukin 6 (IL-6) and miR-155-3p were highly expressed in H-GDEs. Further experiments showed that IL-6 and miR-155-3p induced M2-like macrophage polarization via the IL-6-pSTAT3-miR-155-3p-autophagy-pSTAT3 positive feedback loop, which promotes glioma progression. Our study clarifies a mechanism by which hypoxia and glioma influence autophagy and M2-like macrophage polarization via exosomes, which could advance the formation of the immunosuppressive microenvironment. Our findings suggest that IL-6 and miR-155-3p may be novel biomarkers for diagnosing glioma and that treatments targeting autophagy and the STAT3 pathway may contribute to antitumor immunotherapy.
Collapse
Affiliation(s)
- Jianye Xu
- Department of Neurosurgery, Qilu Hospital, Cheeloo College of Medicine and Institute of Brain and Brain-Inspired Science, Shandong University, Jinan, 250012, Shandong, China.,Shandong Key Laboratory of Brain Function Remodeling, Jinan, 250012, Shandong, China
| | - Jian Zhang
- Department of Neurosurgery, Qilu Hospital, Cheeloo College of Medicine and Institute of Brain and Brain-Inspired Science, Shandong University, Jinan, 250012, Shandong, China.,Shandong Key Laboratory of Brain Function Remodeling, Jinan, 250012, Shandong, China.,Department of Neurosurgery, Dezhou People's Hospital, Dezhou, 253000, Shandong, China
| | - Zongpu Zhang
- Department of Neurosurgery, Qilu Hospital, Cheeloo College of Medicine and Institute of Brain and Brain-Inspired Science, Shandong University, Jinan, 250012, Shandong, China.,Shandong Key Laboratory of Brain Function Remodeling, Jinan, 250012, Shandong, China
| | - Zijie Gao
- Department of Neurosurgery, Qilu Hospital, Cheeloo College of Medicine and Institute of Brain and Brain-Inspired Science, Shandong University, Jinan, 250012, Shandong, China.,Shandong Key Laboratory of Brain Function Remodeling, Jinan, 250012, Shandong, China
| | - Yanhua Qi
- Department of Neurosurgery, Qilu Hospital, Cheeloo College of Medicine and Institute of Brain and Brain-Inspired Science, Shandong University, Jinan, 250012, Shandong, China.,Shandong Key Laboratory of Brain Function Remodeling, Jinan, 250012, Shandong, China
| | - Wei Qiu
- Department of Neurosurgery, Qilu Hospital, Cheeloo College of Medicine and Institute of Brain and Brain-Inspired Science, Shandong University, Jinan, 250012, Shandong, China.,Shandong Key Laboratory of Brain Function Remodeling, Jinan, 250012, Shandong, China
| | - Ziwen Pan
- Department of Neurosurgery, Qilu Hospital, Cheeloo College of Medicine and Institute of Brain and Brain-Inspired Science, Shandong University, Jinan, 250012, Shandong, China.,Shandong Key Laboratory of Brain Function Remodeling, Jinan, 250012, Shandong, China
| | - Qindong Guo
- Department of Neurosurgery, Qilu Hospital, Cheeloo College of Medicine and Institute of Brain and Brain-Inspired Science, Shandong University, Jinan, 250012, Shandong, China.,Shandong Key Laboratory of Brain Function Remodeling, Jinan, 250012, Shandong, China
| | - Boyan Li
- Department of Neurosurgery, Qilu Hospital, Cheeloo College of Medicine and Institute of Brain and Brain-Inspired Science, Shandong University, Jinan, 250012, Shandong, China.,Shandong Key Laboratory of Brain Function Remodeling, Jinan, 250012, Shandong, China
| | - Shulin Zhao
- Department of Neurosurgery, Qilu Hospital, Cheeloo College of Medicine and Institute of Brain and Brain-Inspired Science, Shandong University, Jinan, 250012, Shandong, China.,Shandong Key Laboratory of Brain Function Remodeling, Jinan, 250012, Shandong, China
| | - Xiaofan Guo
- Department of Neurosurgery, Qilu Hospital, Cheeloo College of Medicine and Institute of Brain and Brain-Inspired Science, Shandong University, Jinan, 250012, Shandong, China.,Shandong Key Laboratory of Brain Function Remodeling, Jinan, 250012, Shandong, China
| | - Mingyu Qian
- Department of Neurosurgery, Qilu Hospital, Cheeloo College of Medicine and Institute of Brain and Brain-Inspired Science, Shandong University, Jinan, 250012, Shandong, China.,Shandong Key Laboratory of Brain Function Remodeling, Jinan, 250012, Shandong, China
| | - Zihang Chen
- Department of Neurosurgery, Qilu Hospital, Cheeloo College of Medicine and Institute of Brain and Brain-Inspired Science, Shandong University, Jinan, 250012, Shandong, China.,Shandong Key Laboratory of Brain Function Remodeling, Jinan, 250012, Shandong, China
| | - Shaobo Wang
- Department of Neurosurgery, Qilu Hospital, Cheeloo College of Medicine and Institute of Brain and Brain-Inspired Science, Shandong University, Jinan, 250012, Shandong, China.,Shandong Key Laboratory of Brain Function Remodeling, Jinan, 250012, Shandong, China
| | - Xiao Gao
- Department of Neurosurgery, Qilu Hospital, Cheeloo College of Medicine and Institute of Brain and Brain-Inspired Science, Shandong University, Jinan, 250012, Shandong, China.,Shandong Key Laboratory of Brain Function Remodeling, Jinan, 250012, Shandong, China
| | - Shouji Zhang
- Department of Neurosurgery, Qilu Hospital, Cheeloo College of Medicine and Institute of Brain and Brain-Inspired Science, Shandong University, Jinan, 250012, Shandong, China.,Shandong Key Laboratory of Brain Function Remodeling, Jinan, 250012, Shandong, China
| | - Huizhi Wang
- Department of Neurosurgery, Qilu Hospital, Cheeloo College of Medicine and Institute of Brain and Brain-Inspired Science, Shandong University, Jinan, 250012, Shandong, China.,Shandong Key Laboratory of Brain Function Remodeling, Jinan, 250012, Shandong, China
| | - Xing Guo
- Department of Neurosurgery, Qilu Hospital, Cheeloo College of Medicine and Institute of Brain and Brain-Inspired Science, Shandong University, Jinan, 250012, Shandong, China.,Shandong Key Laboratory of Brain Function Remodeling, Jinan, 250012, Shandong, China
| | - Ping Zhang
- Department of Neurosurgery, Qilu Hospital, Cheeloo College of Medicine and Institute of Brain and Brain-Inspired Science, Shandong University, Jinan, 250012, Shandong, China.,Shandong Key Laboratory of Brain Function Remodeling, Jinan, 250012, Shandong, China
| | - Rongrong Zhao
- Department of Neurosurgery, Qilu Hospital, Cheeloo College of Medicine and Institute of Brain and Brain-Inspired Science, Shandong University, Jinan, 250012, Shandong, China.,Shandong Key Laboratory of Brain Function Remodeling, Jinan, 250012, Shandong, China
| | - Hao Xue
- Department of Neurosurgery, Qilu Hospital, Cheeloo College of Medicine and Institute of Brain and Brain-Inspired Science, Shandong University, Jinan, 250012, Shandong, China. .,Shandong Key Laboratory of Brain Function Remodeling, Jinan, 250012, Shandong, China.
| | - Gang Li
- Department of Neurosurgery, Qilu Hospital, Cheeloo College of Medicine and Institute of Brain and Brain-Inspired Science, Shandong University, Jinan, 250012, Shandong, China. .,Shandong Key Laboratory of Brain Function Remodeling, Jinan, 250012, Shandong, China.
| |
Collapse
|
25
|
Arranz-Solís D, Mukhopadhyay D, Saeij JJP. Toxoplasma Effectors that Affect Pregnancy Outcome. Trends Parasitol 2021; 37:283-295. [PMID: 33234405 PMCID: PMC7954850 DOI: 10.1016/j.pt.2020.10.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 10/18/2020] [Accepted: 10/26/2020] [Indexed: 12/13/2022]
Abstract
As an immune-privileged organ, the placenta can tolerate the introduction of antigens without inducing a strong inflammatory response that would lead to abortion. However, for the control of intracellular pathogens, a strong Th1 response characterized by the production of interferon-γ is needed. Thus, invasion of the placenta by intracellular parasites puts the maternal immune system in a quandary: The proinflammatory response needed to eliminate the pathogen can also lead to abortion. Toxoplasma is a highly successful parasite that causes lifelong chronic infections and is a major cause of abortions in humans and livestock. Here, we discuss how Toxoplasma strain type and parasite effectors influence host cell signaling pathways, and we speculate about how this might affect the outcome of gestation.
Collapse
Affiliation(s)
- David Arranz-Solís
- Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California, Davis, Davis, CA, USA
| | - Debanjan Mukhopadhyay
- Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California, Davis, Davis, CA, USA
| | - Jeroen J P Saeij
- Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California, Davis, Davis, CA, USA.
| |
Collapse
|
26
|
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.
Collapse
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
| |
Collapse
|
27
|
Kochanowsky JA, Thomas KK, Koshy AA. ROP16-Mediated Activation of STAT6 Suppresses Host Cell Reactive Oxygen Species Production, Facilitating Type III Toxoplasma gondii Growth and Survival. mBio 2021; 12:e03305-20. [PMID: 33653884 PMCID: PMC8092286 DOI: 10.1128/mbio.03305-20] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Accepted: 01/22/2021] [Indexed: 12/21/2022] Open
Abstract
Polymorphic effector proteins determine the susceptibility of Toxoplasma gondii strains to IFN-γ-mediated clearance mechanisms deployed by murine host cells. However, less is known about the influence of these polymorphic effector proteins on IFN-γ-independent clearance mechanisms. Here, we show that deletion of one such polymorphic effector protein, ROP16, from a type III background leads to a defect in parasite growth and survival in unstimulated human fibroblasts and murine macrophages. Rescue of these defects requires a ROP16 with a functional kinase domain and the ability to activate a specific family of host cell transcription factors (STAT3, 5a, and 6). The growth and survival defects correlate with an accumulation of host cell reactive oxygen species (ROS) and are prevented by treatment with an ROS inhibitor. Exogenous activation of STAT3 and 6 suppresses host cell ROS production during infection with ROP16-deficient parasites and depletion of STAT6, but not STAT3 or 5a, causes an accumulation of ROS in cells infected with wild-type parasites. Pharmacological inhibition of NOX2 and mitochondrially derived ROS also rescues growth and survival of ROP16-deficient parasites. Collectively, these findings reveal an IFN-γ-independent mechanism of parasite restriction in human cells that is subverted by injection of ROP16 by type III parasites.IMPORTANCEToxoplasma gondii is an obligate intracellular parasite that infects up to one-third of the world's population. Control of the parasite is largely accomplished by IFN-γ-dependent mechanisms that stimulate innate and adaptive immune responses. Parasite suppression of IFN-γ-stimulated responses has been linked to proteins that the parasite secretes into its host cell. These secreted proteins vary by T. gondii strain and determine strain-specific lethality in mice. How these strain-specific polymorphic effector proteins affect IFN-γ-independent parasite control mechanisms in human and murine cells is not well known. This study shows that one such secreted protein, ROP16, enables efficient parasite growth and survival by suppressing IFN-γ-independent production of ROS by human and mouse cells.
Collapse
Affiliation(s)
| | | | - Anita A Koshy
- Department of Immunobiology, University of Arizona, Tucson, Arizona, USA
- BIO5 Institute, University of Arizona, Tucson, Arizona, USA
- Department of Neurology, University of Arizona, Tucson, Arizona, USA
| |
Collapse
|
28
|
Snyder LM, Denkers EY. From Initiators to Effectors: Roadmap Through the Intestine During Encounter of Toxoplasma gondii With the Mucosal Immune System. Front Cell Infect Microbiol 2021; 10:614701. [PMID: 33505924 PMCID: PMC7829212 DOI: 10.3389/fcimb.2020.614701] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Accepted: 11/24/2020] [Indexed: 12/26/2022] Open
Abstract
The gastrointestinal tract is a major portal of entry for many pathogens, including the protozoan parasite Toxoplasma gondii. Billions of people worldwide have acquired T. gondii at some point in their life, and for the vast majority this has led to latent infection in the central nervous system. The first line of host defense against Toxoplasma is located within the intestinal mucosa. Appropriate coordination of responses by the intestinal epithelium, intraepithelial lymphocytes, and lamina propria cells results in an inflammatory response that controls acute infection. Under some conditions, infection elicits bacterial dysbiosis and immune-mediated tissue damage in the intestine. Here, we discuss the complex interactions between the microbiota, the epithelium, as well as innate and adaptive immune cells in the intestinal mucosa that induce protective immunity, and that sometimes switch to inflammatory pathology as T. gondii encounters tissues of the gut.
Collapse
Affiliation(s)
- Lindsay M Snyder
- Center for Evolutionary and Theoretical Immunology and Department of Biology, University of New Mexico, Albuquerque, NM, United States
| | - Eric Y Denkers
- Center for Evolutionary and Theoretical Immunology and Department of Biology, University of New Mexico, Albuquerque, NM, United States
| |
Collapse
|
29
|
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: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [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.
Collapse
Affiliation(s)
| | | | - Jeroen P. J. Saeij
- Department of Pathology, Microbiology & Immunology, School of Veterinary Medicine, University of California, Davis, Davis, CA, United States
| |
Collapse
|
30
|
Transcriptional Profiling Suggests T Cells Cluster around Neurons Injected with Toxoplasma gondii Proteins. mSphere 2020; 5:5/5/e00538-20. [PMID: 32878927 PMCID: PMC7471001 DOI: 10.1128/msphere.00538-20] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Like other persistent intracellular pathogens, Toxoplasma gondii, a protozoan parasite, has evolved to evade the immune system and establish a chronic infection in specific cells and organs, including neurons in the CNS. Understanding T. gondii’s persistence in neurons holds the potential to identify novel, curative drug targets. The work presented here offers new insights into the neuron-T. gondii interaction in vivo. By transcriptionally profiling neurons manipulated by T. gondii, we unexpectedly revealed that immune cells, and specifically CD8+ T cells, appear to cluster around these neurons, suggesting that CD8+ T cells specifically recognize parasite-manipulated neurons. Such a possibility supports evidence from other labs that questions the long-standing dogma that neurons are often persistently infected because they are not directly recognized by immune cells such as CD8+ T cells. Collectively, these data suggest we reconsider the broader role of neurons in the context of infection and neuroinflammation. Toxoplasma gondii’s tropism for and persistence in the central nervous system (CNS) underlies the symptomatic disease that T. gondii causes in humans. Our recent work has shown that neurons are the primary CNS cell with which Toxoplasma interacts and which it infects in vivo. This predilection for neurons suggests that T. gondii’s persistence in the CNS depends specifically upon parasite manipulation of the host neurons. Yet, most work on T. gondii-host cell interactions has been done in vitro and in nonneuronal cells. We address this gap by utilizing our T. gondii-Cre system that allows permanent marking and tracking of neurons injected with parasite effector proteins in vivo. Using laser capture microdissection (LCM) and RNA sequencing using RNA-seq, we isolated and transcriptionally profiled T. gondii-injected neurons (TINs), Bystander neurons (nearby non-T. gondii-injected neurons), and neurons from uninfected mice (controls). These profiles show that TIN transcriptomes significantly differ from the transcriptomes of Bystander and control neurons and that much of this difference is driven by increased levels of transcripts from immune cells, especially CD8+ T cells and monocytes. These data suggest that when we used LCM to isolate neurons from infected mice, we also picked up fragments of CD8+ T cells and monocytes clustering in extreme proximity around TINs and, to a lesser extent, Bystander neurons. In addition, we found that T. gondii transcripts were primarily found in the TIN transcriptome, not in the Bystander transcriptome. Collectively, these data suggest that, contrary to common perception, neurons that directly interact with or harbor parasites can be recognized by CD8+ T cells. IMPORTANCE Like other persistent intracellular pathogens, Toxoplasma gondii, a protozoan parasite, has evolved to evade the immune system and establish a chronic infection in specific cells and organs, including neurons in the CNS. Understanding T. gondii’s persistence in neurons holds the potential to identify novel, curative drug targets. The work presented here offers new insights into the neuron-T. gondii interaction in vivo. By transcriptionally profiling neurons manipulated by T. gondii, we unexpectedly revealed that immune cells, and specifically CD8+ T cells, appear to cluster around these neurons, suggesting that CD8+ T cells specifically recognize parasite-manipulated neurons. Such a possibility supports evidence from other labs that questions the long-standing dogma that neurons are often persistently infected because they are not directly recognized by immune cells such as CD8+ T cells. Collectively, these data suggest we reconsider the broader role of neurons in the context of infection and neuroinflammation.
Collapse
|
31
|
Giorgio S, Gallo-Francisco PH, Roque GAS, Flóro E Silva M. Granulomas in parasitic diseases: the good and the bad. Parasitol Res 2020; 119:3165-3180. [PMID: 32789534 DOI: 10.1007/s00436-020-06841-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Accepted: 08/02/2020] [Indexed: 12/12/2022]
Abstract
Parasitic diseases affect more than one billion people worldwide, and most of them are chronic conditions in which the treatment and prevention are difficult. The appearance of granulomas, defined as organized and compact structures of macrophages and other immune cells, during various parasitic diseases is frequent, since these structures will only form when individual immune cells do not control the invading agent. Th2-typering various parasitic diseases are frequent, since these structures will only form when individual immune cells do not control the invading agent. The characterization of granulomas in different parasitic diseases, as well as recent findings in this field, is discussed in this review, in order to understand the significance of the granuloma and its modulation in the host-parasite interaction and in the immune, pathological, and parasitological aspects of this interaction. The parasitic granulomatous diseases granulomatous amebic encephalitis, toxoplasmosis, leishmaniasis, neurocysticercosis, and schistosomiasis mansoni are discussed as well as the mechanistic and dynamical aspects of the infectious granulomas.
Collapse
Affiliation(s)
- Selma Giorgio
- Department of Animal Biology, Biology Institute, State University of Campinas, Campinas, 13083-865, Brazil.
| | | | | | - Marina Flóro E Silva
- Department of Animal Biology, Biology Institute, State University of Campinas, Campinas, 13083-865, Brazil
| |
Collapse
|
32
|
Kong L, Jiang D, He C, Xia J, Wei H, Zhou L, Peng H. TgROP18 targets IL20RB for host-defense-related-STAT3 activation during Toxoplasma gondii infection. Parasit Vectors 2020; 13:400. [PMID: 32767999 PMCID: PMC7412674 DOI: 10.1186/s13071-020-04251-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Accepted: 07/20/2020] [Indexed: 11/17/2022] Open
Abstract
Background Toxoplasma gondii is an opportunistic protozoan infecting almost one-third of the world’s population. Toxoplasma gondii rhoptry protein 18 (TgROP18) is a key virulence factor determining the parasite’s acute virulence and is secreted into host cells during infection. We previously identified the interaction of TgROP18 and host cell immune-related receptor protein IL20RB, and observed the activation of STAT3 in human keratinocytes (HaCaT) cells infected by the rop16 knockout RH strain, though TgROP16 is regarded as being responsible for host STAT3 activation during T. gondii invasion. Therefore, we hypothesize TgROP18 can activate host STAT3 through binding to IL20RB. Methods CRISPR-CAS9 technology was used to generate the ROP16 and ROP18 double knockout RH strain, RH-∆rop16∆rop18. SDS-PAGE and western blot were used to detect STAT3 activation in different HaCaT cells with high endogenous IL20RB expression treated with T. gondii tachyzoites infection, recombinant ROP18, or IL-20. FRET and co-immunoprecipitation (Co-IP) was used to detect the protein-protein interaction. Results We observed that TgROP18 was involved in a synergic activation of the host JAK/STAT3 pathway together with TgROP16 in human HaCaT cells infected with T. gondii or treated with recombinant TgROP18 protein, stimulating host proinflammatory immune responses such as expression of TNF-α. The effect of recombinant ROP18 on STAT3 phosphorylation was presented in a dose-dependent manner. Additionally, TgROP18 was identified to target IL20RB on its extracellular domain. When we treated different cell lines with the recombinant ROP18, STAT3 phosphorylation could only be observed in the cells with endogenous IL20RB expression, such as HaCaT cells. Conclusions These findings indicate that TgROP18-IL20RB interaction upon T. gondii invasion was involved in STAT3 activation, which is associated with host cell defense.![]()
Collapse
Affiliation(s)
- Ling Kong
- Department of Pathogen Biology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515, Guangdong Province, China
| | - Dan Jiang
- Department of Pathogen Biology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515, Guangdong Province, China
| | - Cheng He
- Department of Pathogen Biology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515, Guangdong Province, China
| | - Jing Xia
- Department of Pathogen Biology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515, Guangdong Province, China
| | - Haixia Wei
- Department of Pathogen Biology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515, Guangdong Province, China
| | - Lijuan Zhou
- Department of Pathogen Biology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515, Guangdong Province, China
| | - Hongjuan Peng
- Department of Pathogen Biology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515, Guangdong Province, China.
| |
Collapse
|
33
|
Rastogi S, Xue Y, Quake SR, Boothroyd JC. Differential Impacts on Host Transcription by ROP and GRA Effectors from the Intracellular Parasite Toxoplasma gondii. mBio 2020; 11:e00182-20. [PMID: 32518180 PMCID: PMC7373195 DOI: 10.1128/mbio.00182-20] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Accepted: 05/06/2020] [Indexed: 12/21/2022] Open
Abstract
The intracellular parasite Toxoplasma gondii employs a vast array of effector proteins from the rhoptry and dense granule organelles to modulate host cell biology; these effectors are known as ROPs and GRAs, respectively. To examine the individual impacts of ROPs and GRAs on host gene expression, we developed a robust, novel protocol to enrich for ultrapure populations of a naturally occurring and reproducible population of host cells called uninfected-injected (U-I) cells, which Toxoplasma injects with ROPs but subsequently fails to invade. We then performed single-cell transcriptomic analysis at 1 to 3 h postinfection on U-I cells (as well as on uninfected and infected controls) arising from infection with either wild-type parasites or parasites lacking the MYR1 protein, which is required for soluble GRAs to cross the parasitophorous vacuole membrane (PVM) and reach the host cell cytosol. Based on comparisons of infected and U-I cells, the host's earliest response to infection appears to be driven primarily by the injected ROPs, which appear to induce immune and cellular stress pathways. These ROP-dependent proinflammatory signatures appear to be counteracted by at least some of the MYR1-dependent GRAs and may be enhanced by the MYR-independent GRAs (which are found embedded within the PVM). Finally, signatures detected in uninfected bystander cells from the infected monolayers suggest that MYR1-dependent paracrine effects also counteract inflammatory ROP-dependent processes.IMPORTANCE This work performs transcriptomic analysis of U-I cells, captures the earliest stage of a host cell's interaction with Toxoplasma gondii, and dissects the effects of individual classes of parasite effectors on host cell biology.
Collapse
Affiliation(s)
- Suchita Rastogi
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, California, USA
| | - Yuan Xue
- Department of Bioengineering, Stanford University, Stanford, California, USA
| | - Stephen R Quake
- Department of Bioengineering, Stanford University, Stanford, California, USA
- Department of Applied Physics, Stanford University, Stanford, California, USA
- Chan Zuckerberg Biohub, San Francisco, California, USA
| | - John C Boothroyd
- Department of Bioengineering, Stanford University, Stanford, California, USA
| |
Collapse
|
34
|
Mukhopadhyay D, Arranz-Solís D, Saeij JPJ. Toxoplasma GRA15 and GRA24 are important activators of the host innate immune response in the absence of TLR11. PLoS Pathog 2020; 16:e1008586. [PMID: 32453782 PMCID: PMC7274473 DOI: 10.1371/journal.ppat.1008586] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 06/05/2020] [Accepted: 04/30/2020] [Indexed: 12/13/2022] Open
Abstract
The murine innate immune response against Toxoplasma gondii is predominated by the interaction of TLR11/12 with Toxoplasma profilin. However, mice lacking Tlr11 or humans, who do not have functional TLR11 or TLR12, still elicit a strong innate immune response upon Toxoplasma infection. The parasite factors that determine this immune response are largely unknown. Herein, we investigated two dense granule proteins (GRAs) secreted by Toxoplasma, GRA15 and GRA24, for their role in stimulating the innate immune response in Tlr11-/- mice and in human cells, which naturally lack TLR11/TLR12. Our results show that GRA15 and GRA24 synergistically shape the early immune response and parasite virulence in Tlr11-/- mice, with GRA15 as the predominant effector. Nevertheless, acute virulence in Tlr11-/- mice is still dominated by allelic combinations of ROP18 and ROP5, which are effectors that determine evasion of the immunity-related GTPases. In human macrophages, GRA15 and GRA24 play a major role in the induction of IL12, IL18 and IL1β secretion. We further show that GRA15/GRA24-mediated IL12, IL18 and IL1β secretion activates IFNγ secretion by peripheral blood mononuclear cells (PBMCs), which controls Toxoplasma proliferation. Taken together, our study demonstrates the important role of GRA15 and GRA24 in activating the innate immune response in hosts lacking TLR11.
Collapse
Affiliation(s)
- Debanjan Mukhopadhyay
- Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California Davis, Davis, California, United States of America
| | - David Arranz-Solís
- Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California Davis, Davis, California, United States of America
| | - Jeroen P. J. Saeij
- Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California Davis, Davis, California, United States of America
- * E-mail:
| |
Collapse
|
35
|
Park J, Hunter CA. The role of macrophages in protective and pathological responses to Toxoplasma gondii. Parasite Immunol 2020; 42:e12712. [PMID: 32187690 DOI: 10.1111/pim.12712] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 02/12/2020] [Accepted: 02/24/2020] [Indexed: 02/06/2023]
Abstract
The ability of Toxoplasma gondii to cause clinical disease in immune-competent and immune-deficient hosts coupled with its ease of use in vitro and availability of murine models has led to its use as a model organism to study how the immune system controls an intracellular infection. This article reviews the studies that established the role of the cytokine IFN-γ in the activation of macrophages to control T gondii and the events that lead to the mobilization and expansion of macrophage populations and their ability to limit parasite replication. Macrophages also have pro-inflammatory functions that promote protective NK and T-cell activities as well as regulatory properties that facilitate the resolution of inflammation. Nevertheless, while macrophages are important in determining the outcome of infection, T gondii has evolved mechanisms to subvert macrophage activation and can utilize their migratory activities to promote dissemination and these two properties underlie the ability of this parasite to persist and cause disease.
Collapse
Affiliation(s)
- Jeongho Park
- University of Pennsylvania School of Veterinary Medicine, Philadelphia, PA, USA.,Kangwon National University College of Veterinary Medicine and Institute of Veterinary Science, Chuncheon, Korea
| | | |
Collapse
|