1
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Valleau D, Sidik SM, Godoy LC, Acevedo‐Sánchez Y, Pasaje CFA, Huynh M, Carruthers VB, Niles JC, Lourido S. A conserved complex of microneme proteins mediates rhoptry discharge in Toxoplasma. EMBO J 2023; 42:e113155. [PMID: 37886905 PMCID: PMC10690463 DOI: 10.15252/embj.2022113155] [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: 11/27/2022] [Revised: 09/19/2023] [Accepted: 09/25/2023] [Indexed: 10/28/2023] Open
Abstract
Apicomplexan parasites discharge specialized organelles called rhoptries upon host cell contact to mediate invasion. The events that drive rhoptry discharge are poorly understood, yet essential to sustain the apicomplexan parasitic life cycle. Rhoptry discharge appears to depend on proteins secreted from another set of organelles called micronemes, which vary in function from allowing host cell binding to facilitation of gliding motility. Here we examine the function of the microneme protein CLAMP, which we previously found to be necessary for Toxoplasma gondii host cell invasion, and demonstrate its essential role in rhoptry discharge. CLAMP forms a distinct complex with two other microneme proteins, the invasion-associated SPATR, and a previously uncharacterized protein we name CLAMP-linked invasion protein (CLIP). CLAMP deficiency does not impact parasite adhesion or microneme protein secretion; however, knockdown of any member of the CLAMP complex affects rhoptry discharge. Phylogenetic analysis suggests orthologs of the essential complex components, CLAMP and CLIP, are ubiquitous across apicomplexans. SPATR appears to act as an accessory factor in Toxoplasma, but despite incomplete conservation is also essential for invasion during Plasmodium falciparum blood stages. Together, our results reveal a new protein complex that mediates rhoptry discharge following host-cell contact.
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Affiliation(s)
| | | | - Luiz C Godoy
- Department of Biological EngineeringMassachusetts Institute of TechnologyCambridgeMAUSA
| | | | | | - My‐Hang Huynh
- Department of Microbiology and ImmunologyUniversity of Michigan Medical SchoolAnn ArborMIUSA
| | - Vern B Carruthers
- Department of Microbiology and ImmunologyUniversity of Michigan Medical SchoolAnn ArborMIUSA
| | - Jacquin C Niles
- Department of Biological EngineeringMassachusetts Institute of TechnologyCambridgeMAUSA
| | - Sebastian Lourido
- Whitehead InstituteCambridgeMAUSA
- Biology DepartmentMassachusetts Institute of TechnologyCambridgeMAUSA
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2
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Cao Y, Song W, Chen X. Multivalent sialic acid materials for biomedical applications. Biomater Sci 2023; 11:2620-2638. [PMID: 36661319 DOI: 10.1039/d2bm01595a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Sialic acid is a kind of monosaccharide expressed on the non-reducing end of glycoproteins or glycolipids. It acts as a signal molecule combining with its natural receptors such as selectins and siglecs (sialic acid-binding immunoglobulin-like lectins) in intercellular interactions like immunological surveillance and leukocyte infiltration. The last few decades have witnessed the exploration of the roles that sialic acid plays in different physiological and pathological processes and the use of sialic acid-modified materials as therapeutics for related diseases like immune dysregulation and virus infection. In this review, we will briefly introduce the biomedical function of sialic acids in organisms and the utilization of multivalent sialic acid materials for targeted drug delivery as well as therapeutic applications including anti-inflammation and anti-virus.
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Affiliation(s)
- Yusong Cao
- Key Laboratory of Polymer Ecomaterials, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, China. .,University of Science and Technology of China, Hefei, 230026, China
| | - Wantong Song
- Key Laboratory of Polymer Ecomaterials, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, China. .,University of Science and Technology of China, Hefei, 230026, China.,Jilin Biomedical Polymers Engineering Laboratory, Changchun, 130022, China
| | - Xuesi Chen
- Key Laboratory of Polymer Ecomaterials, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, China. .,University of Science and Technology of China, Hefei, 230026, China.,Jilin Biomedical Polymers Engineering Laboratory, Changchun, 130022, China
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3
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De Mattos LC, Ferreira AIC, de Oliveira KY, Nakashima F, Brandão CC. The Potential Contribution of ABO, Lewis and Secretor Histo-Blood Group Carbohydrates in Infection by Toxoplasma gondii. Front Cell Infect Microbiol 2021; 11:671958. [PMID: 34222043 PMCID: PMC8251793 DOI: 10.3389/fcimb.2021.671958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Accepted: 05/31/2021] [Indexed: 11/19/2022] Open
Abstract
The glycosyltransferases encoded by genes from the human ABO, Lewis, and Secretor histo-blood group systems synthesize part of the carbohydrate antigens in hematopoietic and non-hematopoietic tissues. The combined action of these glycosyltransferases strongly influences cell, tissue, mucosa, and exocrine secretion carbohydrate phenotypes, including those serving as habitat for mutualistic and pathogenic microorganisms. A set of reports investigated associations between Toxoplasma gondii infection and the ABO histo-blood group system, but the results are contradictory. As T. gondii uses the gastrointestinal tract as a route for infection, and in this organ, the expression of ABO, Lewis, and Secretor histo-blood group carbohydrates occurs, it is reasonable to suppose some biological relationship between them. This text reviewed association studies published in recent decades focusing on the potential contribution of the ABO, Lewis, and Secretor histo-blood group carbohydrates and infection by T. gondii.
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Affiliation(s)
- Luiz Carlos De Mattos
- Immunogenetics Laboratory, Molecular Biology Department, Faculty of Medicine - FAMERP, São José do Rio Preto, Brazil
| | - Ana Iara Costa Ferreira
- Immunogenetics Laboratory, Molecular Biology Department, Faculty of Medicine - FAMERP, São José do Rio Preto, Brazil
| | - Karina Younan de Oliveira
- Immunogenetics Laboratory, Molecular Biology Department, Faculty of Medicine - FAMERP, São José do Rio Preto, Brazil
| | - Fabiana Nakashima
- Immunogenetics Laboratory, Molecular Biology Department, Faculty of Medicine - FAMERP, São José do Rio Preto, Brazil
| | - Cinara Cássia Brandão
- Immunogenetics Laboratory, Molecular Biology Department, Faculty of Medicine - FAMERP, São José do Rio Preto, Brazil.,FAMERP Toxoplasma Research Group, Molecular Biology Department, Faculty of Medicine - FAMERP, São José do Rio Preto, Brazil
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4
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Cavalcante T, Medeiros MM, Mule SN, Palmisano G, Stolf BS. The Role of Sialic Acids in the Establishment of Infections by Pathogens, With Special Focus on Leishmania. Front Cell Infect Microbiol 2021; 11:671913. [PMID: 34055669 PMCID: PMC8155805 DOI: 10.3389/fcimb.2021.671913] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Accepted: 04/28/2021] [Indexed: 12/31/2022] Open
Abstract
Carbohydrates or glycans are ubiquitous components of the cell surface which play crucial biological and structural roles. Sialic acids (Sias) are nine-carbon atoms sugars usually present as terminal residues of glycoproteins and glycolipids on the cell surface or secreted. They have important roles in cellular communication and also in infection and survival of pathogens. More than 20 pathogens can synthesize or capture Sias from their hosts and incorporate them into their own glycoconjugates and derivatives. Sialylation of pathogens’ glycoconjugates may be crucial for survival inside the host for numerous reasons. The role of Sias in protozoa such as Trypanosoma and Leishmania was demonstrated in previous studies. This review highlights the importance of Sias in several pathogenic infections, focusing on Leishmania. We describe in detail the contributions of Sias, Siglecs (sialic acid binding Ig-like lectins) and Neuraminidase 1 (NEU 1) in the course of Leishmania infection. A detailed view on the structural and functional diversity of Leishmania-related Sias and host-cell receptors will be provided, as well as the results of functional studies performed with different Leishmania species.
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Affiliation(s)
- Tainá Cavalcante
- Laboratory of Leishmaniasis, Department of Parasitology, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
| | - Mariana Medina Medeiros
- Laboratory of Leishmaniasis, Department of Parasitology, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
| | - Simon Ngao Mule
- GlycoProteomics Laboratory, Department of Parasitology, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
| | - Giuseppe Palmisano
- GlycoProteomics Laboratory, Department of Parasitology, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
| | - Beatriz Simonsen Stolf
- Laboratory of Leishmaniasis, Department of Parasitology, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
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5
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Xing M, Yang N, Jiang N, Wang D, Sang X, Feng Y, Chen R, Wang X, Chen Q. A Sialic Acid-Binding Protein SABP1 of Toxoplasma gondii Mediates Host Cell Attachment and Invasion. J Infect Dis 2021; 222:126-135. [PMID: 32060530 PMCID: PMC7296849 DOI: 10.1093/infdis/jiaa072] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Accepted: 02/13/2020] [Indexed: 12/26/2022] Open
Abstract
Many obligate intracellular apicomplexan parasites have adapted a distinct invasion mechanism involving a close interaction between the parasite ligands and the sialic acid (SA) receptor. We found that sialic acid binding protein-1 (SABP1), localized on the outer membrane of the zoonotic parasite Toxoplasma gondii, readily binds to sialic acid on the host cell surface. The binding was sensitive to neuraminidase treatment. Cells preincubated with recombinant SABP1 protein resisted parasite invasion in vitro. The parasite lost its invasion capacity and animal infectivity after the SABP1 gene was deleted, whereas complementation of the SABP1 gene restored the virulence of the knockout strain. These data establish the critical role of SABP1 in the invasion process of T. gondii. The previously uncharacterized protein, SABP1, facilitated T. gondii attachment and invasion via sialic acid receptors.
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Affiliation(s)
- Mengen Xing
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, Shenyang Agricultural University, Shenyang, China.,Research Unit for Pathogenic Mechanisms of Zoonotic Parasites, Chinese Academy of Medical Sciences, Shenyang, China
| | - Na Yang
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, Shenyang Agricultural University, Shenyang, China
| | - Ning Jiang
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, Shenyang Agricultural University, Shenyang, China.,Research Unit for Pathogenic Mechanisms of Zoonotic Parasites, Chinese Academy of Medical Sciences, Shenyang, China
| | - Dawei Wang
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, Shenyang Agricultural University, Shenyang, China.,Research Unit for Pathogenic Mechanisms of Zoonotic Parasites, Chinese Academy of Medical Sciences, Shenyang, China
| | - Xiaoyu Sang
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, Shenyang Agricultural University, Shenyang, China.,Research Unit for Pathogenic Mechanisms of Zoonotic Parasites, Chinese Academy of Medical Sciences, Shenyang, China
| | - Ying Feng
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, Shenyang Agricultural University, Shenyang, China.,Research Unit for Pathogenic Mechanisms of Zoonotic Parasites, Chinese Academy of Medical Sciences, Shenyang, China
| | - Ran Chen
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, Shenyang Agricultural University, Shenyang, China.,Research Unit for Pathogenic Mechanisms of Zoonotic Parasites, Chinese Academy of Medical Sciences, Shenyang, China
| | - Xinyi Wang
- College of Basic Education, Shenyang Agricultural University, Shenyang, China
| | - Qijun Chen
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, Shenyang Agricultural University, Shenyang, China.,Research Unit for Pathogenic Mechanisms of Zoonotic Parasites, Chinese Academy of Medical Sciences, Shenyang, China
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6
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Yang N, Xing M, Ding Y, Wang D, Guo X, Sang X, Li J, Li C, Wang Y, Feng Y, Chen R, Wang X, Jiang N, Chen Q. The Putative TCP-1 Chaperonin Is an Important Player Involved in Sialic Acid-Dependent Host Cell Invasion by Toxoplasma gondii. Front Microbiol 2020; 11:258. [PMID: 32153542 PMCID: PMC7047128 DOI: 10.3389/fmicb.2020.00258] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Accepted: 02/04/2020] [Indexed: 01/17/2023] Open
Abstract
Host cell invasion by Toxoplasma gondii is crucial for the survival and proliferation of parasite. The process of T. gondii tachyzoite invasion requires interaction between parasite proteins and receptors on the surface of host cells. Sialic acid is one of the important receptors for host cell invasion by T. gondii. However, the parasite-derived proteins interacting with sialic acid have not been well characterized. In this study, a novel protein named putative TCP-1 chaperonin (TGME49_318410) in T. gondii (TgTCP-1) was targeted and characterized. TgTCP-1 protein colocalized with MIC3 protein, which could be secreted from T. gondii tachyzoites, and this protein showed a specific binding activity to sialic acid, and DC and Vero cells in vitro. The binding of TgTCP-1 protein to DC and Vero cells were inhibited by either pre-incubation with free sialic acid or neuraminidase treatment of the cells. Moreover, a significant reduction of T. gondii invasion in Vero cells was observed after pre-incubation of the cells with recombinant TgTCP-1 protein. These results illustrated that TgTCP-1 is an important molecule involved in sialic acid-dependent host cell invasion by T. gondii.
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Affiliation(s)
- Na Yang
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, China
| | - Mengen Xing
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, China.,The Research Unit for Pathogenic Mechanisms of Zoonotic Parasites, Chinese Academy of Medical Sciences, Shenyang, China
| | - Yingying Ding
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, China
| | - Dawei Wang
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, China.,The Research Unit for Pathogenic Mechanisms of Zoonotic Parasites, Chinese Academy of Medical Sciences, Shenyang, China.,College of Food Science and Engineering, Shenyang Agricultural University, Shenyang, China
| | - Xiaogai Guo
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, China
| | - Xiaoyu Sang
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, China
| | - Jiaqi Li
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, China
| | - Chenghuan Li
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, China
| | - Yanhu Wang
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, China
| | - Ying Feng
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, China
| | - Ran Chen
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, China.,The Research Unit for Pathogenic Mechanisms of Zoonotic Parasites, Chinese Academy of Medical Sciences, Shenyang, China
| | - Xinyi Wang
- College of Basic Sciences, Shenyang Agricultural University, Shenyang, China
| | - Ning Jiang
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, China.,The Research Unit for Pathogenic Mechanisms of Zoonotic Parasites, Chinese Academy of Medical Sciences, Shenyang, China
| | - Qijun Chen
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, China.,The Research Unit for Pathogenic Mechanisms of Zoonotic Parasites, Chinese Academy of Medical Sciences, Shenyang, China
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7
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Sikorski PM, Commodaro AG, Grigg ME. Toxoplasma gondii Recruits Factor H and C4b-Binding Protein to Mediate Resistance to Serum Killing and Promote Parasite Persistence in vivo. Front Immunol 2020; 10:3105. [PMID: 32010145 PMCID: PMC6979546 DOI: 10.3389/fimmu.2019.03105] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Accepted: 12/19/2019] [Indexed: 01/14/2023] Open
Abstract
Regulating complement is an important step in the establishment of infection by microbial pathogens. Toxoplasma gondii actively resists complement-mediated killing in non-immune human serum (NHS) by inactivating C3b, however the precise molecular basis is unknown. Here, a flow cytometry-based C3b binding assay demonstrated that Type II strains had significantly higher levels of surface-bound C3b than Type I strains. However, both strains efficiently inactivated C3b and were equally resistant to serum killing, suggesting that resistance is not strain-dependent. Toxoplasma activated both the lectin (LP) and alternative (AP) pathways, and the deposition of C3b was both strain and lectin-dependent. A flow cytometry-based lectin binding assay identified strain-specific differences in the level and heterogeneity of surface glycans detected. Specifically, increased lectin-binding by Type II strains correlated with higher levels of the LP recognition receptor mannose binding lectin (MBL). Western blot analyses demonstrated that Toxoplasma recruits both classical pathway (CP) and LP regulator C4b-binding proteins (C4BP) and AP regulator Factor H (FH) to the parasite surface to inactivate bound C3b-iC3b and C3dg and limit formation of the C5b-9 attack complex. Blocking FH and C4BP contributed to increased C5b-9 formation in vitro. However, parasite susceptibility in vitro was only impacted when FH was blocked, indicating that down regulation of the alternative pathway by FH may be more critical for parasite resistance. Infection of C3 deficient mice led to uncontrolled parasite growth, acute mortality, and reduced antibody production, indicating that both the presence of C3, and the ability of the parasite to inactivate C3, was protective. Taken together, our results establish that Toxoplasma regulation of the complement system renders mice resistant to acute infection by limiting parasite proliferation in vivo, but susceptible to chronic infection, with all mice developing transmissible cysts to maintain its life cycle.
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Affiliation(s)
- Patricia M Sikorski
- Molecular Parasitology Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States.,Department of Microbiology and Immunology, Georgetown University Medical Centre, Georgetown University, Washington, DC, United States
| | - Alessandra G Commodaro
- Molecular Parasitology Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Michael E Grigg
- Molecular Parasitology Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States
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8
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Costa Mendonça-Natividade F, Duque Lopes C, Ricci-Azevedo R, Sardinha-Silva A, Figueiredo Pinzan C, Paiva Alegre-Maller AC, L Nohara L, B Carneiro A, Panunto-Castelo A, C Almeida I, Roque-Barreira MC. Receptor Heterodimerization and Co-Receptor Engagement in TLR2 Activation Induced by MIC1 and MIC4 from Toxoplasma gondii. Int J Mol Sci 2019; 20:ijms20205001. [PMID: 31658592 PMCID: PMC6829480 DOI: 10.3390/ijms20205001] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Revised: 09/17/2019] [Accepted: 09/30/2019] [Indexed: 01/07/2023] Open
Abstract
The microneme organelles of Toxoplasma gondii tachyzoites release protein complexes (MICs), including one composed of the transmembrane protein MIC6 plus MIC1 and MIC4. In this complex, carbohydrate recognition domains of MIC1 and MIC4 are exposed and interact with terminal sialic acid and galactose residues, respectively, of host cell glycans. Recently, we demonstrated that MIC1 and MIC4 binding to the N-glycans of Toll-like receptor (TLR) 2 and TLR4 on phagocytes triggers cell activation and pro-inflammatory cytokine production. Herein, we investigated the requirement for TLR2 heterodimerization and co-receptors in MIC-induced responses, as well as the signaling molecules involved. We used MICs to stimulate macrophages and HEK293T cells transfected with TLR2 and TLR1 or TLR6, both with or without the co-receptors CD14 and CD36. Then, the cell responses were analyzed, including nuclear factor-kappa B (NF-κB) activation and cytokine production, which showed that (1) only TLR2, among the studied factors, is crucial for MIC-induced cell activation; (2) TLR2 heterodimerization augments, but is not critical for, activation; (3) CD14 and CD36 enhance the response to MIC stimulus; and (4) MICs activate cells through a transforming growth factor beta-activated kinase 1 (TAK1)-, mammalian p38 mitogen-activated protein kinase (p38)-, and NF-κB-dependent pathway. Remarkably, among the studied factors, the interaction of MIC1 and MIC4 with TLR2 N-glycans is sufficient to induce cell activation, which promotes host protection against T. gondii infection.
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Affiliation(s)
- Flávia Costa Mendonça-Natividade
- Laboratory of Immunochemistry and Glycobiology, Department of Cell and Molecular Biology and Pathogenic Bioagents, Ribeirão Preto Medical School, University of São Paulo (FMRP/USP), Ribeirão Preto SP 14049-900, Brazil.
| | - Carla Duque Lopes
- Laboratory of Immunochemistry and Glycobiology, Department of Cell and Molecular Biology and Pathogenic Bioagents, Ribeirão Preto Medical School, University of São Paulo (FMRP/USP), Ribeirão Preto SP 14049-900, Brazil.
| | - Rafael Ricci-Azevedo
- Laboratory of Immunochemistry and Glycobiology, Department of Cell and Molecular Biology and Pathogenic Bioagents, Ribeirão Preto Medical School, University of São Paulo (FMRP/USP), Ribeirão Preto SP 14049-900, Brazil.
| | - Aline Sardinha-Silva
- Laboratory of Immunochemistry and Glycobiology, Department of Cell and Molecular Biology and Pathogenic Bioagents, Ribeirão Preto Medical School, University of São Paulo (FMRP/USP), Ribeirão Preto SP 14049-900, Brazil.
| | - Camila Figueiredo Pinzan
- Laboratory of Immunochemistry and Glycobiology, Department of Cell and Molecular Biology and Pathogenic Bioagents, Ribeirão Preto Medical School, University of São Paulo (FMRP/USP), Ribeirão Preto SP 14049-900, Brazil.
| | - Ana Claudia Paiva Alegre-Maller
- Laboratory of Immunochemistry and Glycobiology, Department of Cell and Molecular Biology and Pathogenic Bioagents, Ribeirão Preto Medical School, University of São Paulo (FMRP/USP), Ribeirão Preto SP 14049-900, Brazil.
| | - Lilian L Nohara
- Border Biomedical Research Center (BBRC), Department of Biological Sciences, University of Texas at El Paso (UTEP), El Paso, TX 79968, USA.
| | - Alan B Carneiro
- Border Biomedical Research Center (BBRC), Department of Biological Sciences, University of Texas at El Paso (UTEP), El Paso, TX 79968, USA.
- Institute of Medical Biochemistry, Program of Molecular Biology and Biotechnology at Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro RJ 21941-599, Brazil.
| | - Ademilson Panunto-Castelo
- Department of Biology, Faculty of Philosophy, Sciences and Letters at Ribeirão Preto, University of São Paulo USP (FFCLRP/USP), Ribeirão Preto SP 14040-900, Brazil.
| | - Igor C Almeida
- Border Biomedical Research Center (BBRC), Department of Biological Sciences, University of Texas at El Paso (UTEP), El Paso, TX 79968, USA.
| | - Maria Cristina Roque-Barreira
- Laboratory of Immunochemistry and Glycobiology, Department of Cell and Molecular Biology and Pathogenic Bioagents, Ribeirão Preto Medical School, University of São Paulo (FMRP/USP), Ribeirão Preto SP 14049-900, Brazil.
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9
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Proteomic and structural characterization of self-assembled vesicles from excretion/secretion products of Toxoplasma gondii. J Proteomics 2019; 208:103490. [DOI: 10.1016/j.jprot.2019.103490] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 07/25/2019] [Accepted: 08/14/2019] [Indexed: 01/13/2023]
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10
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The lectin-specific activity of Toxoplasma gondii microneme proteins 1 and 4 binds Toll-like receptor 2 and 4 N-glycans to regulate innate immune priming. PLoS Pathog 2019; 15:e1007871. [PMID: 31226171 PMCID: PMC6608980 DOI: 10.1371/journal.ppat.1007871] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 07/03/2019] [Accepted: 05/25/2019] [Indexed: 01/01/2023] Open
Abstract
Infection of host cells by Toxoplasma gondii is an active process, which is regulated by secretion of microneme (MICs) and rhoptry proteins (ROPs and RONs) from specialized organelles in the apical pole of the parasite. MIC1, MIC4 and MIC6 assemble into an adhesin complex secreted on the parasite surface that functions to promote infection competency. MIC1 and MIC4 are known to bind terminal sialic acid residues and galactose residues, respectively and to induce IL-12 production from splenocytes. Here we show that rMIC1- and rMIC4-stimulated dendritic cells and macrophages produce proinflammatory cytokines, and they do so by engaging TLR2 and TLR4. This process depends on sugar recognition, since point mutations in the carbohydrate-recognition domains (CRD) of rMIC1 and rMIC4 inhibit innate immune cells activation. HEK cells transfected with TLR2 glycomutants were selectively unresponsive to MICs. Following in vitro infection, parasites lacking MIC1 or MIC4, as well as expressing MIC proteins with point mutations in their CRD, failed to induce wild-type (WT) levels of IL-12 secretion by innate immune cells. However, only MIC1 was shown to impact systemic levels of IL-12 and IFN-γ in vivo. Together, our data show that MIC1 and MIC4 interact physically with TLR2 and TLR4 N-glycans to trigger IL-12 responses, and MIC1 is playing a significant role in vivo by altering T. gondii infection competency and murine pathogenesis. Toxoplasmosis is caused by the protozoan Toxoplasma gondii, belonging to the Apicomplexa phylum. This phylum comprises important parasites able to infect a broad diversity of animals, including humans. A particularity of T. gondii is its ability to invade virtually any nucleated cell of all warm-blooded animals through an active process, which depends on the secretion of adhesin proteins. These proteins are discharged by specialized organelles localized in the parasite apical region, and termed micronemes and rhoptries. We show in this study that two microneme proteins from T. gondii utilize their adhesion activity to stimulate innate immunity. These microneme proteins, denoted MIC1 and MIC4, recognize specific sugars on receptors expressed on the surface of mammalian immune cells. This binding activates these innate immune cells to secrete cytokines, which promotes efficient host defense mechanisms against the parasite and regulate their pathogenesis. This activity promotes a chronic infection by controlling parasite replication during acute infection.
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11
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Abstract
Toxoplasma gondii is a highly prevalent protozoon that can infect all warm-blooded animals, including humans. It is frequently used as an Apicomplexan parasite model in
research. In this review, the invasion mechanism of T. gondii is described as a representative Apicomplexan parasite. The invasion machinery of T. gondii
consists of the moving junction and the glideosome, which is a specific motor system for Apicomplexan parasites. I provide details about the moving junction, parasite-secreted proteins and
host adhesion receptors, the glideosome, and calcium signaling, which generates the power for the gliding mobility of T. gondii. A detailed understanding of parasite
invasion can be useful for the development of new effective drugs to inhibit this event and disrupt the Apicomplexan life cycle.
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Affiliation(s)
- Kentaro Kato
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido 080-8555, Japan
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12
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Santos A, Bueno PR. Glycoprotein assay based on the optimized immittance signal of a redox tagged and lectin-based receptive interface. Biosens Bioelectron 2016; 83:368-78. [DOI: 10.1016/j.bios.2016.04.043] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Revised: 04/08/2016] [Accepted: 04/14/2016] [Indexed: 12/29/2022]
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13
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Kato K, Murata Y, Horiuchi N, Inomata A, Terkawi MA, Ishiwa A, Ogawa Y, Fukumoto S, Matsuhisa F, Koyama K. Dextran sulfate inhibits acute Toxoplama gondii infection in pigs. Parasit Vectors 2016; 9:134. [PMID: 26956033 PMCID: PMC4784389 DOI: 10.1186/s13071-016-1421-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Accepted: 03/03/2016] [Indexed: 12/03/2022] Open
Abstract
Background Toxoplasma gondii is a highly prevalent protozoan that can infect all warm-blooded animals, including humans. Its definitive hosts are Felidae and its intermediate hosts include various other mammals and birds, including pigs. It is found in the meat of livestock which is a major source of human infection. Hence the control of toxoplasmosis in pigs is important for public health. We previously showed that dextran sulfate (DS), especially DS10 (dextran sulfate MW 10 kDa), is effective against T. gondii infection both in vitro and in mice. In this study, we asked whether DS affects T. gondii infection of pigs, one of the main animal sources of toxoplasmosis transmission to humans. Methods Fourteen-day-old male pigs (n = 10) were infected with T. gondii and then immediately treated with different doses of DS10; clinical, pathological, and immunological analyses were performed 5 days post-infection. Results DS10 had an inhibitory effect on toxoplasmosis in pigs. Intravenous injection of DS10 prevented the symptoms of toxoplasmosis and reduced the parasite burden and inflammation induced by T. gondii infection. High-dose DS10 (500 μg per head) caused reversible hepatocellular degeneration of the liver; middle-dose DS10 (50 μg per head) was effective against toxoplasmosis in pigs without causing this side effect. Conclusions Our data suggest that middle-dose DS10 led to minimal clinical symptoms of T. gondii infection and caused little hepatocellular degeneration in our pig model, thereby demonstrating its potential as a new treatment for toxoplasmosis. These data should be very beneficial to those interested in the control of toxoplasmosis in pigs. Electronic supplementary material The online version of this article (doi:10.1186/s13071-016-1421-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Kentaro Kato
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido, 080-8555, Japan. .,Department of Veterinary Microbiology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan.
| | - Yuho Murata
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido, 080-8555, Japan.
| | - Noriyuki Horiuchi
- Department of Basic Veterinary Medicine, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido, 080-8555, Japan.
| | - Atsuko Inomata
- Department of Veterinary Microbiology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan.
| | - Mohamad Alaa Terkawi
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido, 080-8555, Japan.
| | - Akiko Ishiwa
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido, 080-8555, Japan. .,Department of Veterinary Microbiology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan.
| | - Yohsuke Ogawa
- National Institute of Animal Health, National Agriculture and Food Research Organization (NARO), 3-1-5 Kannondai, Tsukuba, Ibaraki, 305-0856, Japan.
| | - Shinya Fukumoto
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido, 080-8555, Japan.
| | - Fumikazu Matsuhisa
- Department of Basic Veterinary Medicine, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido, 080-8555, Japan.
| | - Kenji Koyama
- Department of Basic Veterinary Medicine, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido, 080-8555, Japan.
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Santos A, Carvalho FC, Roque-Barreira MC, Zorzetto-Fernandes AL, Gimenez-Romero D, Monzó I, Bueno PR. Evidence for Conformational Mechanism on the Binding of TgMIC4 with β-Galactose-Containing Carbohydrate Ligand. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:12111-12119. [PMID: 26488670 DOI: 10.1021/acs.langmuir.5b03141] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
A deeper understanding of the role of sialic/desialylated groups during TgMIC4-glycoproteins interactions has importance to better clarify the odd process of host cell invasion by members of the apicomplexan phylum. Within this context, we evaluated the interaction established by recombinant TgMIC4 (the whole molecule) with sialylated (bovine fetuin) and desialylated (asialofetuin) glycoproteins by using functionalized quartz crystal microbalance with dissipation monitoring (QCM-D). A suitable receptive surface containing recombinant TgMIC4 for monitoring β-galactose-containing carbohydrate ligand (limit of quantification ∼ 40 μM) was designed and used as biomolecular recognition platform to study the binding and conformational mechanisms of TgMIC4 during the interaction with glycoprotein containing (fetuin), or not, terminal sialic group (asialofetuin). It was inferred that the binding/interaction monitoring depends on the presence/absence of sialic groups in target protein and is possible to be differentiated through a slower binding kinetic step using QCM-D approach (which we are inferring to be thus associated with β-galactose ligand). This slower binding/interaction step is likely supposed (from mechanical energetic analysis obtained in QCM-D measurements) to be involved with Toxoplasma gondii (the causative agent of toxoplasmosis) parasitic invasion accompanied by ligand (galactose) induced binding conformational change (i.e., cell internalization process can be additionally dependent on structural conformational changes, controlled by the absence of sialic groups and to the specific binding with galactose), in addition to TgMIC4-glycoprotein solely recognition binding process.
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Affiliation(s)
- Adriano Santos
- Institute of Chemistry, Physical Chemistry Department, Nanobionics Laboratory, Universidade Estadual Paulista (São Paulo State University) , CP 355, 14800-060 Araraquara, São Paulo, Brazil
| | - Fernanda C Carvalho
- Institute of Chemistry, Physical Chemistry Department, Nanobionics Laboratory, Universidade Estadual Paulista (São Paulo State University) , CP 355, 14800-060 Araraquara, São Paulo, Brazil
| | - Maria-Cristina Roque-Barreira
- Departamento de Biologia Celular e Molecular e Bioagentes Patogênicos, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo (USP) , Av. dos Bandeirantes, 3900, Ribeirão Preto, 14049-900 São Paulo, Brazil
| | - André Luiz Zorzetto-Fernandes
- Departamento de Biologia Celular e Molecular e Bioagentes Patogênicos, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo (USP) , Av. dos Bandeirantes, 3900, Ribeirão Preto, 14049-900 São Paulo, Brazil
| | - David Gimenez-Romero
- Departamento de Química Física, Facultad de Química, Universitat de València , Avda. Dr. Moliner 50, 46100 Burjassot, Valencia, Spain
| | - Isidro Monzó
- Departamento de Química Física, Facultad de Química, Universitat de València , Avda. Dr. Moliner 50, 46100 Burjassot, Valencia, Spain
| | - Paulo R Bueno
- Institute of Chemistry, Physical Chemistry Department, Nanobionics Laboratory, Universidade Estadual Paulista (São Paulo State University) , CP 355, 14800-060 Araraquara, São Paulo, Brazil
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15
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Weight CM, Jones EJ, Horn N, Wellner N, Carding SR. Elucidating pathways of Toxoplasma gondii invasion in the gastrointestinal tract: involvement of the tight junction protein occludin. Microbes Infect 2015; 17:698-709. [PMID: 26183539 DOI: 10.1016/j.micinf.2015.07.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2015] [Revised: 06/17/2015] [Accepted: 07/02/2015] [Indexed: 01/28/2023]
Abstract
Toxoplasma gondii is an obligate intracellular parasite infecting one third of the world's population. The small intestine is the parasite's primary route of infection, although the pathway of epithelium transmigration remains unclear. Using an in vitro invasion assay and live imaging we showed that T. gondii (RH) tachyzoites infect and transmigrate between adjacent intestinal epithelial cells in polarized monolayers without altering barrier integrity, despite eliciting the production of specific inflammatory mediators and chemokines. During invasion, T. gondii co-localized with occludin. Reducing the levels of endogenous cellular occludin with specific small interfering RNAs significantly reduced the ability of T. gondii to penetrate between and infect epithelial cells. Furthermore, an in vitro invasion and binding assays using recombinant occludin fragments established the capacity of the parasite to bind occludin and in particular to the extracellular loops of the protein. These findings provide evidence for occludin playing a role in the invasion of T. gondii in small intestinal epithelial cells.
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Affiliation(s)
- Caroline M Weight
- Gut Health and Food Safety Institute Strategic Programme, Norwich Research Park, Norwich, NR4 7UA, UK; Norwich Medical School, University of East Anglia, Norwich Research Park, Norwich, NR4 7UA, UK
| | - Emily J Jones
- Gut Health and Food Safety Institute Strategic Programme, Norwich Research Park, Norwich, NR4 7UA, UK; Norwich Medical School, University of East Anglia, Norwich Research Park, Norwich, NR4 7UA, UK
| | - Nikki Horn
- Gut Health and Food Safety Institute Strategic Programme, Norwich Research Park, Norwich, NR4 7UA, UK
| | - Nikolaus Wellner
- Analytical Sciences Unit, Institute of Food Research, Norwich Research Park, Norwich, NR4 7UA, UK
| | - Simon R Carding
- Gut Health and Food Safety Institute Strategic Programme, Norwich Research Park, Norwich, NR4 7UA, UK; Norwich Medical School, University of East Anglia, Norwich Research Park, Norwich, NR4 7UA, UK.
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16
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Baba M, Sato M, Kitoh K, Takashima Y. The distribution pattern of α2,3- and α2,6-linked sialic acids affects host cell preference in Toxoplasma gondii. Exp Parasitol 2015; 155:74-81. [PMID: 26003519 DOI: 10.1016/j.exppara.2015.05.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Revised: 04/27/2015] [Accepted: 05/11/2015] [Indexed: 01/11/2023]
Abstract
Tachyzoites of Toxoplasma gondii, an obligate intracellular parasite, actively invade almost all types of nucleated cells. However, T. gondii tachyzoites preferentially infect particular types of animal tissue cells. The mechanism underlying the host cell preference of T. gondii is not yet known. In this study, we found that enzymatic removal of α2,3- but not α2,6-linked sialic acids on the surface of Vero cells decreased T. gondii tachyzoite adhesion or invasion to the treated cells. Although Chinese hamster ovary (CHO) cells express only α2,3-linked sialic acid, a genetically modified CHO cell line constructed by transfection with the α2,6-sialiltransferase gene contains subpopulations with a variety of expression patterns of α2,3- and α2,6-linked sialic acids. When T. gondii tachyzoites were added to the modified CHO cells, the tachyzoites preferentially attached to cells belonging to a subpopulation of cells that highly expressed α2,3-linked sialic acids. Additionally, multiple regression analysis performed to analyse the relationship between the amount of α2,3-linked/α2,6-linked sialic acids and parasite-expressed fluorescence intensity suggested that more tachyzoites adhered to individual α2,3-linked sialic acid rich-cells than to α2,3-linked sialic acid-poor/null cells. The results of confocal laser microscopy confirmed this finding. These results indicate that the host cell preference of T. gondii was, at least partially, affected by the distribution pattern of α2,3-, but almost never α2,6-linked sialic acids on host cells.
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Affiliation(s)
- Minami Baba
- Department of Veterinary Parasitology, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan
| | - Masanao Sato
- National Institute for Basic Biology, Okazaki Institute for Integrative Bioscience, 5-1 Higashiyama, Okazaki 444-8787, Japan
| | - Katsuya Kitoh
- Department of Veterinary Parasitology, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan
| | - Yasuhiro Takashima
- Department of Veterinary Parasitology, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan.
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Kato K, Ishiwa A. The role of carbohydrates in infection strategies of enteric pathogens. Trop Med Health 2014; 43:41-52. [PMID: 25859152 PMCID: PMC4361345 DOI: 10.2149/tmh.2014-25] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2014] [Accepted: 11/04/2014] [Indexed: 01/08/2023] Open
Abstract
Enteric pathogens cause considerable public health concerns worldwide including tropical regions. Here, we review the roles of carbohydrates in the infection strategies of various enteric pathogens including viruses, bacteria and protozoa, which infect the epithelial lining of the human and animal intestine. At host cell entry, enteric viruses, including norovirus, recognize mainly histo-blood group antigens. At the initial step of bacterial infections, carbohydrates also function as receptors for attachment. Here, we describe the function of carbohydrates in infection by Salmonella enterica and several bacterial species that produce a variety of fimbrial adhesions. During invasion by enteropathogenic protozoa, apicomplexan parasites utilize sialic acids or sulfated glycans. Carbohydrates serve as receptors for infection by these microbes; however, their usage of carbohydrates varies depending on the microbe. On the surface of the mucosal tissues of the gastrointestinal tract, various carbohydrate moieties are present and play a crucial role in infection, representing the site of infection or route of access for most microbes. During the infection and/or invasion process of the microbes, carbohydrates function as receptors for various microbes, but they can also function as a barrier to infection. One approach to develop effective prophylactic and therapeutic antimicrobial agents is to modify the drug structure. Another approach is to modify the mode of inhibition of infection depending on the individual pathogen by using and mimicking the interactions with carbohydrates. In addition, similarities in mode of infection may also be utilized. Our findings will be useful in the development of new drugs for the treatment of enteric pathogens.
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Affiliation(s)
- Kentaro Kato
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine , Inada-cho, Obihiro, Hokkaido 080-8555, Japan ; Department of Veterinary Microbiology, Graduate School of Agricultural and Life Sciences, The University of Tokyo , 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Akiko Ishiwa
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine , Inada-cho, Obihiro, Hokkaido 080-8555, Japan ; Department of Veterinary Microbiology, Graduate School of Agricultural and Life Sciences, The University of Tokyo , 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
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18
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Zhang Y, Jiang N, Jia B, Chang Z, Zhang Y, Wei X, Zhou J, Wang H, Zhao X, Yu S, Song M, Tu Z, Lu H, Yin J, Wahlgren M, Chen Q. A comparative study on the heparin-binding proteomes of Toxoplasma gondii and Plasmodium falciparum. Proteomics 2014; 14:1737-45. [PMID: 24888565 DOI: 10.1002/pmic.201400003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2014] [Revised: 05/06/2014] [Accepted: 05/22/2014] [Indexed: 11/09/2022]
Abstract
Toxoplasma gondii is an obligatory intracellular apicomplexan parasite which exploits host cell surface components in cell invasion and intracellular parasitization. Sulfated glycans such as heparin and heparan sulfate have been reported to inhibit cell invasion by T. gondii and other apicomplexan parasites such as Plasmodium falciparum. The aim of this study was to investigate the heparin-binding proteome of T. gondii. The parasite-derived components were affinity-purified on the heparin moiety followed by MS fingerprinting of the proteins. The heparin-binding proteins of T. gondii and P. falciparum were compared based on functionality and affinity to heparin. Among the proteins identified, the invasion-related parasite ligands derived from tachyzoite/merozoite surface and the secretory organelles were prominent. However, the profiles of the proteins were different in terms of affinity to heparin. In T. gondii, the proteins with highest affinity to heparin were the intracellular components with functions of parasite development contrasted to that of P. falciparum, of which the rhoptry-derived proteins were prominently identified. The profiling of the heparin-binding proteins of the two apicomplexan parasites not only explained the mechanism of heparin-mediated host cell invasion inhibition, but also, to a certain extent, revealed that the action of heparin on the parasite extended after endocytosis.
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Affiliation(s)
- Yan Zhang
- Key Laboratory of Zoonosis, Jilin University, Changchun, P. R. China; Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Institute of Military Veterinary, Academy of Military Medical Sciences, Changchun, P. R. China
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α2-3 Sialic acid glycoconjugate loss and its effect on infection with Toxoplasma parasites. Exp Parasitol 2013; 135:479-85. [PMID: 23988663 DOI: 10.1016/j.exppara.2013.08.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Accepted: 08/11/2013] [Indexed: 11/22/2022]
Abstract
Recognition of sialylated glycoconjugates is important for host cell invasion by Apicomplexan parasites. Toxoplasma gondii parasites penetrate host cells via interactions between their microneme proteins and sialylated glycoconjugates on the surface of host cells. However, the role played by sialic acids during infection with T. gondii is not well understood. Here, we focused on the role of α2-3 sialic acid linkages as they appear to be widely expressed in vertebrates. Removal of α2-3 sialic acid linkages on macrophages by neuraminidase treatment did not influence the rate of infection or growth of T. gondii, nor did it affect phagocytosis in vitro. Sialyltransferase ST3Gal-I deficient mice (ST3Gal-I(-/-) mice) lost α2-3 sialic acid linkages in macrophages and spleen cells. The numbers of T. gondii-infected CD11b(+) cells in peritoneal cavities of the infected ST3Gal-I(-/-) mice were relatively lower than those of the infected wild type animals. In addition, CD8(+) T cell populations and numbers in the spleens and peritoneal cavities of the ST3Gal-I(-/-) mice were significantly lower than those in the wild type animals before and after the T. gondii infection. ST3Gal-I(-/-) mice had severe liver damage and reduced survival rates following peritoneal infection with T. gondii. Furthermore, adoptive transfer of immune CD8(+) cells from wild type mice to ST3Gal-I(-/-) mice increased their survival during infection with T. gondii. Our data show that parasite invasion via α2-3 sialic acid linkages might not contribute on host survival and indicate the impact that loss of α2-3 sialic acid linkages has on CD8(+) T cell populations, which are necessary for effective immune responses against infection with T. gondii.
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Bharadwaj AS, Appukuttan B, Wilmarth PA, Pan Y, Stempel AJ, Chipps TJ, Benedetti EE, Zamora DO, Choi D, David LL, Smith JR. Role of the retinal vascular endothelial cell in ocular disease. Prog Retin Eye Res 2013; 32:102-80. [PMID: 22982179 PMCID: PMC3679193 DOI: 10.1016/j.preteyeres.2012.08.004] [Citation(s) in RCA: 120] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2012] [Revised: 08/23/2012] [Accepted: 08/24/2012] [Indexed: 12/14/2022]
Abstract
Retinal endothelial cells line the arborizing microvasculature that supplies and drains the neural retina. The anatomical and physiological characteristics of these endothelial cells are consistent with nutritional requirements and protection of a tissue critical to vision. On the one hand, the endothelium must ensure the supply of oxygen and other nutrients to the metabolically active retina, and allow access to circulating cells that maintain the vasculature or survey the retina for the presence of potential pathogens. On the other hand, the endothelium contributes to the blood-retinal barrier that protects the retina by excluding circulating molecular toxins, microorganisms, and pro-inflammatory leukocytes. Features required to fulfill these functions may also predispose to disease processes, such as retinal vascular leakage and neovascularization, and trafficking of microbes and inflammatory cells. Thus, the retinal endothelial cell is a key participant in retinal ischemic vasculopathies that include diabetic retinopathy and retinopathy of prematurity, and retinal inflammation or infection, as occurs in posterior uveitis. Using gene expression and proteomic profiling, it has been possible to explore the molecular phenotype of the human retinal endothelial cell and contribute to understanding of the pathogenesis of these diseases. In addition to providing support for the involvement of well-characterized endothelial molecules, profiling has the power to identify new players in retinal pathologies. Findings may have implications for the design of new biological therapies. Additional progress in this field is anticipated as other technologies, including epigenetic profiling methods, whole transcriptome shotgun sequencing, and metabolomics, are used to study the human retinal endothelial cell.
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Affiliation(s)
| | | | - Phillip A. Wilmarth
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University
| | - Yuzhen Pan
- Casey Eye Institute, Oregon Health & Science University
| | | | | | | | | | - Dongseok Choi
- Department of Public Health and Preventive Medicine, Oregon Health & Science University
| | - Larry L. David
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University
| | - Justine R. Smith
- Casey Eye Institute, Oregon Health & Science University
- Department of Cell & Developmental Biology, Oregon Health & Science University
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Azzouz N, Kamena F, Laurino P, Kikkeri R, Mercier C, Cesbron-Delauw MF, Dubremetz JF, De Cola L, Seeberger PH. Toxoplasma gondii secretory proteins bind to sulfated heparin structures. Glycobiology 2012; 23:106-20. [DOI: 10.1093/glycob/cws134] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
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Weight CM, Carding SR. The protozoan pathogen Toxoplasma gondii targets the paracellular pathway to invade the intestinal epithelium. Ann N Y Acad Sci 2012; 1258:135-42. [PMID: 22731726 DOI: 10.1111/j.1749-6632.2012.06534.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Abstract Toxoplasma gondii is a ubiquitous parasite found within all mammals and birds worldwide that can cause fatal infections in immunocompromised persons and fetuses. The parasite causes chronic infections by residing in long-living tissues of the muscle and brain. T. gondii infects the host through contaminated meat and water consumption with the gastrointestinal tract (GI tract) being the first point of contact with the host. The mechanisms by which the parasite invades the host through the GI tract are unknown, although it has been suggested that the paracellular pathway is important for parasite dissemination. Studies indicate that epithelial tight junction-associated proteins are affected by T. gondii, although which junctional proteins are affected and the nature of host protein-parasite interactions have not been established. We have uncovered evidence that T. gondii influences the cellular distribution of occludin to transmigrate the intestinal epithelium and suggest how candidate binding partners can be identified.
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Affiliation(s)
- Caroline M Weight
- Institute of Food Research Norwich Medical School, University of East Anglia, Norwich Research Park, Norwich, United Kingdom
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23
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Yeng C, Osman E, Mohamed Z, Noordin R. Detection of immunogenic parasite and host-specific proteins in the sera of active and chronic individuals infected with Toxoplasma gondii. Electrophoresis 2011; 31:3843-9. [PMID: 21080484 DOI: 10.1002/elps.201000038] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Toxoplasma gondii infection in pregnant women may result in abortion and foetal abnormalities, and may be life-threatening in immunocompromised hosts. To identify the potential infection markers of this disease, 2-DE and Western blot methods were employed to study the parasite circulating antigens and host-specific proteins in the sera of T. gondii-infected individuals. The comparisons were made between serum protein profiles of infected (n=31) and normal (n=10) subjects. Antigenic proteins were identified by immunoblotting using pooled sera and monoclonal anti-human IgM-HRP. Selected protein spots were characterised using mass spectrometry. Prominent differences were observed when serum samples of T. gondii-infected individuals and normal controls were compared. A significant up-regulation of host-specific proteins, α(2)-HS glycoprotein and α(1)-B glycoprotein, was also observed in the silver-stained gels of both active and chronic infections. However, only α(2)-HS glycoprotein and α(1)-B glycoprotein in the active infection showed immunoreactivity in Western blots. In addition, three spots of T. gondii proteins were detected, namely (i) hypothetical protein chrXII: 3984434-3 TGME 49, (ii) dual specificity protein phosphatase, catalytic domain TGME 49 and (iii) NADPH-cytochrome p450 reductase TGME 49. Thus, 2-DE approach followed by Western blotting has enabled the identification of five potential infection markers for the diagnosis of toxoplasmosis: three are parasite-specific proteins and two are host-specific proteins.
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Affiliation(s)
- Chen Yeng
- Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, Penang, Malaysia
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Lieke T, Gröbe D, Blanchard V, Grunow D, Tauber R, Zimmermann-Kordmann M, Jacobs T, Reutter W. Invasion of Trypanosoma cruzi into host cells is impaired by N-propionylmannosamine and other N-acylmannosamines. Glycoconj J 2011; 28:31-7. [DOI: 10.1007/s10719-010-9321-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2010] [Revised: 12/16/2010] [Accepted: 12/16/2010] [Indexed: 10/18/2022]
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Boulanger MJ, Tonkin ML, Crawford J. Apicomplexan parasite adhesins: novel strategies for targeting host cell carbohydrates. Curr Opin Struct Biol 2010; 20:551-9. [DOI: 10.1016/j.sbi.2010.08.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2010] [Revised: 07/27/2010] [Accepted: 08/12/2010] [Indexed: 11/25/2022]
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Sialic acids: key determinants for invasion by the Apicomplexa. Int J Parasitol 2010; 40:1145-54. [PMID: 20430033 DOI: 10.1016/j.ijpara.2010.04.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2010] [Revised: 04/17/2010] [Accepted: 04/19/2010] [Indexed: 11/20/2022]
Abstract
Sialic acids are ubiquitously found on the surface of all vertebrate cells at the extremities of glycan chains and widely exploited by viruses and bacteria to enter host cells. Carbohydrate-bearing receptors are equally important for host cell invasion by the obligate intracellular protozoan parasites of the phylum Apicomplexa. Host cell entry is an active process relying crucially on proteins that engage with receptors on the host cell surface and promote adhesion and internalisation. Assembly into complexes, proteolytic processing and oligomerization are important requirements for the functionality of these adhesins. The combination of adhesive proteins with varying stringency in specificity confers some flexibility to the parasite in face of receptor heterogeneity and immune pressure. Sialic acids are now recognised to critically contribute to selective host cell recognition by various species of the phylum.
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Friedrich N, Santos JM, Liu Y, Palma AS, Leon E, Saouros S, Kiso M, Blackman MJ, Matthews S, Feizi T, Soldati-Favre D. Members of a novel protein family containing microneme adhesive repeat domains act as sialic acid-binding lectins during host cell invasion by apicomplexan parasites. J Biol Chem 2009; 285:2064-76. [PMID: 19901027 DOI: 10.1074/jbc.m109.060988] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Numerous intracellular pathogens exploit cell surface glycoconjugates for host cell recognition and entry. Unlike bacteria and viruses, Toxoplasma gondii and other parasites of the phylum Apicomplexa actively invade host cells, and this process critically depends on adhesins (microneme proteins) released onto the parasite surface from intracellular organelles called micronemes (MIC). The microneme adhesive repeat (MAR) domain of T. gondii MIC1 (TgMIC1) recognizes sialic acid (Sia), a key determinant on the host cell surface for invasion by this pathogen. By complementation and invasion assays, we demonstrate that TgMIC1 is one important player in Sia-dependent invasion and that another novel Sia-binding lectin, designated TgMIC13, is also involved. Using BLAST searches, we identify a family of MAR-containing proteins in enteroparasitic coccidians, a subclass of apicomplexans, including T. gondii, suggesting that all these parasites exploit sialylated glycoconjugates on host cells as determinants for enteric invasion. Furthermore, this protein family might provide a basis for the broad host cell range observed for coccidians that form tissue cysts during chronic infection. Carbohydrate microarray analyses, corroborated by structural considerations, show that TgMIC13, TgMIC1, and its homologue Neospora caninum MIC1 (NcMIC1) share a preference for alpha2-3- over alpha2-6-linked sialyl-N-acetyllactosamine sequences. However, the three lectins also display differences in binding preferences. Intense binding of TgMIC13 to alpha2-9-linked disialyl sequence reported on embryonal cells and relatively strong binding to 4-O-acetylated-Sia found on gut epithelium and binding of NcMIC1 to 6'sulfo-sialyl Lewis(x) might have implications for tissue tropism.
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Affiliation(s)
- Nikolas Friedrich
- Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva Centre Medical Universitaire, 1 Rue Michel-Servet, 1211 Geneva 4, Switzerland
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Allman SA, Jensen HH, Vijayakrishnan B, Garnett JA, Leon E, Liu Y, Anthony DC, Sibson NR, Feizi T, Matthews S, Davis BG. Potent Fluoro-oligosaccharide Probes of Adhesion inToxoplasmosis. Chembiochem 2009; 10:2522-9. [DOI: 10.1002/cbic.200900425] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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29
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Santos JM, Lebrun M, Daher W, Soldati D, Dubremetz JF. Apicomplexan cytoskeleton and motors: key regulators in morphogenesis, cell division, transport and motility. Int J Parasitol 2008; 39:153-62. [PMID: 19028497 DOI: 10.1016/j.ijpara.2008.10.007] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2008] [Revised: 10/13/2008] [Accepted: 10/16/2008] [Indexed: 10/21/2022]
Abstract
Protozoan parasites of the phylum Apicomplexa undergo a lytic cycle whereby a single zoite produced by the previous cycle has to encounter a host cell, invade it, multiply to differentiate into a new zoite generation and escape to resume a new cycle. At every step of this lytic cycle, the cytoskeleton and/or the gliding motility apparatus play a crucial role and recent results have elucidated aspects of these processes, especially in terms of the molecular characterization and interaction of the increasing number of partners involved, and the signalling mechanisms implicated. The present review aims to summarize the most recent findings in the field.
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Affiliation(s)
- Joana M Santos
- Department of Microbiology and Molecular Medicine, Faculty of Medicine-University of Geneva CMU, 1 rue Michel-Servet, 1211 Geneva 4, Switzerland
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30
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Hager KM, Carruthers VB. MARveling at parasite invasion. Trends Parasitol 2008; 24:51-4. [PMID: 18203663 DOI: 10.1016/j.pt.2007.10.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2007] [Revised: 10/05/2007] [Accepted: 10/26/2007] [Indexed: 10/22/2022]
Abstract
Micronemal proteins (MICs) are key mediators of cytoadherence and invasion for Toxoplasma gondii. Emerging evidence indicates that carbohydrate binding facilitates Toxoplasma entry into host cells. The recently solved Toxoplasma MIC1s (TgMIC1s) structure reveals the presence of novel specialized domains that can discriminate between glycan residues. Comparison with Plasmodium erythrocyte-binding antigen 175 reveals that terminal sialic acid residues might represent a shared but tailored invasion pathway among apicomplexan parasites.
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Affiliation(s)
- Kristin M Hager
- Department of Biological Sciences, Center for Global Health and Infectious Disease, University of Notre Dame, Notre Dame, IN 46556-0369, USA.
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31
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Blumenschein TMA, Friedrich N, Childs RA, Saouros S, Carpenter EP, Campanero-Rhodes MA, Simpson P, Chai W, Koutroukides T, Blackman MJ, Feizi T, Soldati-Favre D, Matthews S. Atomic resolution insight into host cell recognition by Toxoplasma gondii. EMBO J 2007; 26:2808-20. [PMID: 17491595 PMCID: PMC1888667 DOI: 10.1038/sj.emboj.7601704] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2006] [Accepted: 04/04/2007] [Indexed: 01/07/2023] Open
Abstract
The obligate intracellular parasite Toxoplasma gondii, a member of the phylum Apicomplexa that includes Plasmodium spp., is one of the most widespread parasites and the causative agent of toxoplasmosis. Micronemal proteins (MICs) are released onto the parasite surface just before invasion of host cells and play important roles in host cell recognition, attachment and penetration. Here, we report the atomic structure for a key MIC, TgMIC1, and reveal a novel cell-binding motif called the microneme adhesive repeat (MAR). Using glycoarray analyses, we identified a novel interaction with sialylated oligosaccharides that resolves several prevailing misconceptions concerning TgMIC1. Structural studies of various complexes between TgMIC1 and sialylated oligosaccharides provide high-resolution insights into the recognition of sialylated oligosaccharides by a parasite surface protein. We observe that MAR domains exist in tandem repeats, which provide a highly specialized structure for glycan discrimination. Our work uncovers new features of parasite-receptor interactions at the early stages of host cell invasion, which will assist the design of new therapeutic strategies.
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Affiliation(s)
| | - Nikolas Friedrich
- Department of Microbiology and Genetics, Faculty of Medicine, University of Geneva CMU, Geneva, Switzerland
| | - Robert A Childs
- Glycosciences Laboratory, Division of Medicine, Imperial College London, Middlesex, UK
| | - Savvas Saouros
- Division of Molecular Biosciences, Imperial College London, London, UK
| | | | | | - Peter Simpson
- Division of Molecular Biosciences, Imperial College London, London, UK
| | - Wengang Chai
- Glycosciences Laboratory, Division of Medicine, Imperial College London, Middlesex, UK
| | | | - Michael J Blackman
- Division of Parasitology, National Institute for Medical Research, London, UK
| | - Ten Feizi
- Glycosciences Laboratory, Division of Medicine, Imperial College London, Middlesex, UK
| | - Dominique Soldati-Favre
- Department of Microbiology and Genetics, Faculty of Medicine, University of Geneva CMU, Geneva, Switzerland
| | - Stephen Matthews
- Division of Molecular Biosciences, Imperial College London, London, UK
- Division of Molecular Biosciences, Imperial College of Science, Technology and Medicine, South Kensington Campus, London SW7 2AZ, UK. Tel.: +44 207 594 5315; Fax: +44 207 594 5207; E-mail:
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Vonlaufen N, Naguleswaran A, Gianinazzi C, Hemphill A. Characterization of the fetuin-binding fraction of Neospora caninum tachyzoites and its potential involvement in host-parasite interactions. Parasitology 2007; 134:805-17. [PMID: 17291396 DOI: 10.1017/s0031182006002186] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Terminal sialic acid residues on surface-associated glycoconjugates mediate host cell interactions of many pathogens. Addition of sialic acid-rich fetuin enhanced, and the presence of the sialidiase inhibitor 2-deoxy-2,3-dehydro-N-acetylneuraminic acid reduced, the physical interaction of Neospora caninum tachyzoites and bradyzoites with Vero cell monolayers. Thus, Neospora extracts were subjected to fetuin-agarose affinity chromatography in order to isolate components potentially interacting with sialic acid residues. SDS-PAGE and silver staining of the fetuin binding fraction revealed the presence of a single protein band of approximately 65 kDa, subsequently named NcFBP (Neospora caninum fetuin-binding protein), which was localized at the apical tip of the tachyzoites and was continuously released into the surrounding medium in a temperature-independent manner. NcFBP readily interacted with Vero cells and bound to chondroitin sulfate A and C, and anti-NcFBP antibodies interfered in tachyzoite adhesion to host cell monolayers. In additon, analysis of the fetuin binding fraction by gelatin substrate zymography was performed, and demonstrated the presence of two bands of 96 and 140 kDa exhibiting metalloprotease-activity. The metalloprotease activity readily degraded glycosylated proteins such as fetuin and bovine immunoglobulin G heavy chain, whereas non-glycosylated proteins such as bovine serum albumin and immunoglobulin G light chain were not affected. These findings suggest that the fetuin-binding fraction of Neospora caninum tachyzoites contains components that could be potentially involved in host-parasite interactions.
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Affiliation(s)
- N Vonlaufen
- Institute of Parasitology, Vetsuisse Faculty, University of Berne, Länggass-Strasse 122, CH-3012 Berne, Switzerland
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33
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Wootton EC, Dyrynda EA, Ratcliffe NA. Interaction between non-specific electrostatic forces and humoral factors in haemocyte attachment and encapsulation in the edible cockle, Cerastoderma edule. ACTA ACUST UNITED AC 2006; 209:1326-35. [PMID: 16547303 DOI: 10.1242/jeb.02118] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
In invertebrates, encapsulation is the common immune defence reaction towards foreign bodies, including multicellular parasites, which enter the haemocoel and are too large to be phagocytosed. This immune response has been most extensively studied in insects, in which it is highly complex, involving a diversity of cellular and molecular processes, but little is known of this process in bivalve molluscs. Non-specific physicochemical properties are known to influence parasite-haemocyte interactions in many invertebrates, and these may provide the common basis of encapsulation on which highly specific biochemical interactions are imposed. The present study uses synthetic beads and thread to mimic inactive metacercarial cysts of trematodes, and thus investigates factors involved in the basic, non-specific mechanisms of cell attachment and encapsulation in the edible cockle, Cerastoderma edule. Results showed that positively charged targets stimulated the most vigorous response, and further detailed experiments revealed that non-specific electrostatic forces and humoral plasma factors have a synergistic role in haemocyte attachment and the encapsulation response of C. edule.
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Affiliation(s)
- Emma C Wootton
- School of Environment and Society, University of Wales Swansea, Singleton Park, Swansea SA2 8PP, UK.
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34
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Chipps TJ, Streeter PR, Franc DT, Neumeyer K, Planck SR, Rosenbaum JT, Smith JR. Modification of the Woodruff-Stamper assay demonstrates binding of Toxoplasma gondii tachyzoites to retinal vascular endothelium. J Immunol Methods 2006; 312:209-13. [PMID: 16725152 DOI: 10.1016/j.jim.2006.03.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2005] [Revised: 01/09/2006] [Accepted: 03/02/2006] [Indexed: 11/30/2022]
Abstract
In the human host, infection with the protozoan parasite, Toxoplasma gondii, most commonly involves the eye and/or the brain. Previous work indicates a relative susceptibility of the human retinal vascular endothelium to infection with the T. gondii tachyzoite, which may contribute to this tissue localization. To facilitate the investigation of potential adhesive interactions between parasite and endothelium in the retina, we have modified the Woodruff-Stamper assay, originally described to study lymphocytic-endothelial binding. Vascular endothelium was identified in sections of human retina by Alexa Fluor 594-tagged anti-von Willebrand factor antibody. Binding of yellow fluorescent protein-expressing tachyzoites to endothelium under conditions of flow, simulated by rotation on an orbital shaker, was quantified in a masked fashion using imaging software. We observed multiple yellow spots in contact with Alexa Fluor 594-positive retina, indicating binding of T. gondii tachyzoites to retinal vascular endothelium. This modification of the Woodruff-Stamper assay provides an opportunity to evaluate potential host receptors for T. gondii on the retinal vascular endothelium. In addition, the assay suggests a methodology that could be used to examine adhesion of other microbes to microvasculature in different tissues.
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Affiliation(s)
- T J Chipps
- Casey Eye Institute, Oregon Health and Science University, 3375 SW Terwilliger Blvd, Portland, OR 97239, USA
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35
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Bishop JR, Crawford BE, Esko JD. Cell surface heparan sulfate promotes replication of Toxoplasma gondii. Infect Immun 2005; 73:5395-401. [PMID: 16113255 PMCID: PMC1231081 DOI: 10.1128/iai.73.9.5395-5401.2005] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Previous work suggests that cell surface heparan sulfate acts as a receptor for the Apicomplexan parasite Toxoplasma gondii. Using Chinese hamster ovary cell mutants defective in heparan sulfate biosynthesis, we show that heparan sulfate is necessary and sufficient for infectivity. Further, we demonstrate that the parasite requires N sulfation of heparan sulfate initiated by N-deacetylase/N-sulfotransferase-1, but 2-O sulfation and 6-O sulfation appear to be dispensable. In order to study the role of heparan sulfate in other cell types, we created a conditional allele for N-deacetylase/N-sulfotransferase-1 by using Cre-loxP technology. Mammary tumor cells lacking N-deacetylase/N-sulfotransferase-1 exhibited reduced toxoplasma infectivity like Chinese hamster ovary cell mutants. Surprisingly, heparin, chemically modified heparinoids, and monoclonal antibodies to heparan sulfate had no effect on toxoplasma infection. T. gondii attachment and invasion were unchanged in N-deacetylase/N-sulfotransferase-1-inactivated cells as well, but replication was reduced. Thus, heparan sulfate does not appear to function as a receptor for T. gondii but instead facilitates parasite replication postinvasion.
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Affiliation(s)
- Joseph R Bishop
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093-0687, USA
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36
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Monteiro VG, Lobato CSS, Silva AR, Medina DV, de Oliveira MA, Seabra SH, de Souza W, DaMatta RA. Increased association of Trypanosoma cruzi with sialoadhesin positive mice macrophages. Parasitol Res 2005; 97:380-5. [PMID: 16151743 DOI: 10.1007/s00436-005-1460-1] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2005] [Accepted: 06/16/2005] [Indexed: 10/25/2022]
Abstract
Trypanosoma cruzi is a parasite with large amounts of sialic acid (SA) residues exposed at its surface that seems to be involved in macrophages infection. Some macrophages, present in T. cruzi infected tissues, expresses sialoadhesin (Sn), a receptor that recognizes SA. Thus, the involvement of Sn in the association of T. cruzi to macrophages was investigated. Sn was induced in mice peritoneal macrophages by homologous serum (HS) cultivation. Epimastigotes and trypomastigotes associated more to HS cultured macrophages than to fetal bovine serum (FBS). Blocking of Sn with antibodies reduced the association of trypomastigotes to similar level as for FBS cultured macrophages. Desialylation reduced the association of parasites to HS cultured macrophages indicating the Sn importance. Furthermore, the entrance mechanism of trypomastigotes to Sn positive macrophages has a phagocytic nature as demonstrated by scanning electron microscopy and cytochalasin D treatment. Sn positive macrophages may important in the initial trypomastigote infection, thus in the establishment of Chagas disease.
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Affiliation(s)
- Verônica G Monteiro
- Laboratòrio de Biologia Celular e Tecidual, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense, 28013-600 Parque Califórnia, Campos dos Goytacazes, RJ, Brazil
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Barragan A, Brossier F, Sibley LD. Transepithelial migration of Toxoplasma gondii involves an interaction of intercellular adhesion molecule 1 (ICAM-1) with the parasite adhesin MIC2. Cell Microbiol 2005; 7:561-8. [PMID: 15760456 DOI: 10.1111/j.1462-5822.2005.00486.x] [Citation(s) in RCA: 140] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Toxoplasma gondii crosses non-permissive biological barriers such as the intestine, the blood-brain barrier and the placenta thereby gaining access to tissues where it most commonly causes severe pathology. Herein we show that in the process of migration Toxoplasma initially concentrates around intercellular junctions and probably uses a paracellular pathway to transmigrate across biological barriers. Parasite transmigration required viable and actively motile parasites. Interestingly, the integrity of host cell barriers was not altered during parasite transmigration. As intercellular adhesion molecule 1 (ICAM-1) is upregulated on cellular barriers during Toxoplasma infection, we investigated the role of this receptor in parasite transmigration. Soluble human ICAM-1 and ICAM-1 antibodies inhibited transmigration of parasites across cellular barriers implicating this receptor in the process of transmigration. Furthermore, human ICAM-1 immunoprecipitated the mature form of the parasite adhesin MIC2 present on the parasite surface, indicating that this interaction may contribute to cellular migration. These findings reveal that Toxoplasma exploits the natural cell trafficking pathways in the host to cross cellular barriers and disseminate to deep tissues.
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Affiliation(s)
- Antonio Barragan
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO 63110, USA.
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38
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Bishop JR, Esko JD. The elusive role of heparan sulfate in Toxoplasma gondii infection. Mol Biochem Parasitol 2005; 139:267-9. [PMID: 15664661 DOI: 10.1016/j.molbiopara.2004.11.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/08/2004] [Indexed: 10/26/2022]
Affiliation(s)
- Joseph R Bishop
- Department of Cellular and Molecular Medicine, University of California-San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0687, USA
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39
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Esquenazi D, Alviano CS, de Souza W, Rozental S. The influence of surface carbohydrates during in vitro infection of mammalian cells by the dermatophyte Trichophyton rubrum. Res Microbiol 2004; 155:144-53. [PMID: 15059626 DOI: 10.1016/j.resmic.2003.12.002] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2003] [Accepted: 12/09/2003] [Indexed: 11/17/2022]
Abstract
In order to better understand the role played by surface glycoconjugates during host cell adhesion and endocytosis of Trichophyton rubrum, we looked for the presence of carbohydrate-binding adhesins on the microconidia surface and their role on cellular interaction with epithelial and macrophages cells. The interaction of T. rubrum with chinese hamster ovary epithelial cells and their glycosylation-deficient mutants demonstrated a higher adhesion index in Lec1 and Lec2 mutants, that express mannose and galactose, respectively. Endocytosed fungi were shown preferentially in Lec2 cells. Addition of the carbohydrates to the interaction medium, pretreatment with lectins and with sodium periodate decreased the adhesion and endocytic index for all mutants. The ability of the fungus to penetrate into mammalian cells was confirmed in experiments using macrophages treated with cytochalasin D. Flow cytometric analysis showed that this fungus recognizes mannose and galactose. The binding was inhibited by the addition of methyl alpha-D-mannopyranoside and methyl alpha-D-galactopyranoside, and showed higher fluorescence intensity at 37 than at 28 degrees C. Trypsin treatment and heating of the cells reduced the binding, suggesting a (glyco) protein nature for the microconidia adhesins. The presence of lectin-like molecules in fungus cell could be observed by scanning electron microscopy of the fungus incubated with colloidal-gold labeled neoglycoproteins. Our results suggest that T. rubrum has the ability to invade mammalian cells and expresses carbohydrate-specific adhesins on microconidia surface that recognize mannose and galactose. These adhesins may play an important role on the adhesion and invasion of the fungus during the infectious process of dermatophytosis.
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Affiliation(s)
- Daniele Esquenazi
- Laboratório de Biologia Celular de Fungos, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Ilha do Fundão, 21949-190, Rio de Janeiro, RJ, Brazil
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40
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Coppens I, Joiner KA. Host but not parasite cholesterol controls Toxoplasma cell entry by modulating organelle discharge. Mol Biol Cell 2003; 14:3804-20. [PMID: 12972565 PMCID: PMC196568 DOI: 10.1091/mbc.e02-12-0830] [Citation(s) in RCA: 108] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Host cell cholesterol is implicated in the entry and replication of an increasing number of intracellular microbial pathogens. Although uptake of viral particles via cholesterol-enriched caveolae is increasingly well described, the requirement of cholesterol for internalization of eukaryotic pathogens is poorly understood and is likely to be partly organism specific. We examined the role of cholesterol in active host cell invasion by the protozoan parasite Toxoplasma gondii. The parasitophorous vacuole membrane (PVM) surrounding T. gondii contains cholesterol at the time of invasion. Although cholesterol-enriched parasite apical organelles termed rhoptries discharge at the time of cell entry and contribute to PVM formation, surprisingly, rhoptry cholesterol is not necessary for this process. In contrast, host plasma membrane cholesterol is incorporated into the forming PVM during invasion, through a caveolae-independent mechanism. Unexpectedly, depleting host cell plasma membrane cholesterol blocks parasite internalization by reducing the release of rhoptry proteins that are necessary for invasion. Cholesterol back-addition into host plasma membrane reverses this inhibitory effect of depletion on parasite secretion. These data define a new mechanism by which host cholesterol specifically controls entry of an intracellular pathogen.
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Affiliation(s)
- Isabelle Coppens
- Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut 06520-8022, USA.
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41
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Esquenazi D, de Souza W, Alviano CS, Rozental S. The role of surface carbohydrates on the interaction of microconidia of Trichophyton mentagrophytes with epithelial cells. FEMS IMMUNOLOGY AND MEDICAL MICROBIOLOGY 2003; 35:113-23. [PMID: 12628546 DOI: 10.1016/s0928-8244(03)00007-5] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The presence of carbohydrate-binding adhesins on the microconidia of Trichophyton mentagrophytes surface and their role on cellular interactions were investigated. Flow cytometry showed that this fungus recognizes the sugars mannose and galactose. The binding was inhibited by the addition of methyl alpha-D-mannopyranoside and methyl alpha-D-galactopyranoside, and showed higher fluorescence intensity at 37 degrees C than 28 degrees C. Trypsin treatment and heating of the cells reduced the binding, suggesting a (glyco) protein nature of the microconidia adhesin. The interaction of the fungus to Chinese hamster ovary epithelial cells and its glycosylation-deficient mutants demonstrated a higher adhesion index in Lec1 and Lec2 mutants, which express mannose and galactose, respectively, as the terminal carbohydrate on the cell surface. Endocytosed fungi were shown preferentially in Lec2 cells. Addition of the carbohydrates methyl alpha-D-mannopyranoside and methyl alpha-D-galactopyranoside to the interaction medium, pretreatment of Lec1 and Lec2 cells with lectins Concanavalina A and Arachis hypogaea and pretreatment with sodium periodate decreased the adhesion and the endocytic index. Examination of thin section by transmission electron microscopy showed that after fungal ingestion by Lec2 cells the fungi are enclosed in a 'loose'-type vacuole while the other cells are found within a 'tight'-type membrane-bound cytoplasmic vacuole. Our results suggest the occurrence of carbohydrate-specific adhesins on microconidia surface that recognize mannose and galactose. This may have a role in the adhesion process during the infectious process of dermatophytosis.
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Affiliation(s)
- Daniele Esquenazi
- Laboratório de Biologia Celular de Fungos, Instituto de Biofi;sica Carlos Chagas Filho, CCS- Bloco G, Cidade Universitária, Rio de Janeiro, 21949-970, Brazil.
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42
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Abstract
The surface charge of trypanosomatids was evaluated by means of the binding of cationic particles, as visualized by electron microscopy and by direct measurements of the electrophoretic mobility of cells. The results obtained indicate that most of the trypanosomatids exhibit a negatively charged surface whose value is species specific and varies according to the developmental stages. Sialic acids associated with glycoproteins, glycolipids and phosphate groups are the major components responsible for the net negative surface charge of the trypanosomatids.
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Affiliation(s)
- Thaïs Souto-Padrón
- Laboratório de Biologia de Protozoários, Instituto de Microbiologia Prof. Paulo de Góes, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, 21941-590, Brazil.
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43
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Angata T, Varki A. Chemical diversity in the sialic acids and related alpha-keto acids: an evolutionary perspective. Chem Rev 2002; 102:439-69. [PMID: 11841250 DOI: 10.1021/cr000407m] [Citation(s) in RCA: 935] [Impact Index Per Article: 42.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Takashi Angata
- Glycobiology Research and Training Center, Department of Medicine, University of California-San Diego, La Jolla, California 92093-0687, USA
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44
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Jacquet A, Coulon L, De Nève J, Daminet V, Haumont M, Garcia L, Bollen A, Jurado M, Biemans R. The surface antigen SAG3 mediates the attachment of Toxoplasma gondii to cell-surface proteoglycans. Mol Biochem Parasitol 2001; 116:35-44. [PMID: 11463464 DOI: 10.1016/s0166-6851(01)00297-3] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The attachment of Toxoplasma gondii to target cells is mediated by recognition of cellular heparan sulfate proteoglycans (HSPGs). The present study was performed to determine whether SAG1 and SAG3, two of the parasite surface antigens anchored to the membrane via glycosylphosphatidylinositol groups (GPIs), are involved in the tachyzoite binding to proteoglycans. The use of recombinant soluble forms of these proteins allowed us to demonstrate that SAG3, but not SAG1, interacts specifically with cellular HSPGs. Indeed, soluble recombinant SAG3 protein (recSAG3) was found to bind to immobilized heparin, whereas recSAG1 did not interact with this glycoaminoglycan. The specific adherence of recSAG3 to CHO cells was inhibited by soluble glycoconjugates, of which heparin, fucoidan and dextran sulfate were the most effective. Moreover, binding of recSAG3 to two HSPGs-deficient cell mutants was reduced by up to 80%. Proteoglycan sulfation was critical for SAG3 adherence to HSPGs as incubation of cells in the presence of sodium chlorate drastically reduced the recSAG3 binding. Finally, preincubation of CHO cells with recSAG3 blocked the adsorption of radiolabelled Toxoplasma tachyzoites. Taken together, these results indicate that SAG3 is a first glycoaminoglycan-binding protein associated with Toxoplasma, and SAG3-HSPGs interactions are involved in the parasite attachment to target cells.
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Affiliation(s)
- A Jacquet
- Department of Applied Genetics, Institut de Biologie et de Médicine Moléculaires, Université Libre de Bruxelles, Rue des Professeurs Jeener et Brachet 12, B-6041 Gosselies, Belgium.
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Lourenço EV, Pereira SR, Faça VM, Coelho-Castelo AA, Mineo JR, Roque-Barreira MC, Greene LJ, Panunto-Castelo A. Toxoplasma gondii micronemal protein MIC1 is a lactose-binding lectin. Glycobiology 2001; 11:541-7. [PMID: 11447133 DOI: 10.1093/glycob/11.7.541] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Host cell invasion by Toxoplasma gondii is a multistep process with one of the first steps being the apical release of micronemal proteins that interact with host receptors. We demonstrate here that micronemal protein 1 (MIC1) is a lactose-binding lectin. MIC1 and MIC4 were recovered in the lactose-eluted (Lac(+)) fraction on affinity chromatography on immobilized lactose of the soluble antigen fraction from tachyzoites of the virulent RH strain. MIC1 and MIC4 were both identified by N-terminal microsequencing. MIC4 was also identified by sequencing cDNA clones isolated from an expression library following screening with mouse polyclonal anti-60/70 kDa (Lac(+) proteins) serum. This antiserum localized the Lac(+) proteins on the apical region of T. gondii tachyzoites by confocal microscopy. The Lac(+) fraction induced hemagglutination (mainly type A human erythrocytes), which was inhibited by beta-galactosides (3 mM lactose and 12 mM galactose) but not by up to 100 mM melibiose (alpha-galactoside), fucose, mannose, or glucose or 0.2 mg/ml heparin. The lectin activity of the Lac(+) preparation was attributed to MIC1, because blotted MIC1, but not native MIC4, bound human erythrocyte type A and fetuin. The copurification of MIC1 and MIC4 may have been due to their association, as reported by others. These data suggest that MIC1 may act through its lectin activity during T. gondii infection.
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Affiliation(s)
- E V Lourenço
- Departamento de Biologia Celular e Molecular e Bioagentes Patogênicos, Faculdade de Medicina de Ribeirão Preto, USP, Av. Bandeirantes 3900, 14049-900, Ribeirão Preto, SP, Brazil
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Carruthers VB, Håkansson S, Giddings OK, Sibley LD. Toxoplasma gondii uses sulfated proteoglycans for substrate and host cell attachment. Infect Immun 2000; 68:4005-11. [PMID: 10858215 PMCID: PMC101681 DOI: 10.1128/iai.68.7.4005-4011.2000] [Citation(s) in RCA: 118] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Toxoplasma gondii is an obligate intracellular parasite that actively invades a wide variety of vertebrate cells, although the basis of this pervasive cell recognition is not understood. We demonstrate here that binding to the substratum and to host cells is partially mediated by interaction with sulfated glycosaminoglycans (GAGs). Addition of excess soluble GAGs blocked parasite attachment to serum-coated glass, thereby preventing gliding motility of extracellular parasites. Similarly, excess soluble GAGs decreased the attachment of parasites to human host cells from a variety of lineages, including monocytic, fibroblast, endothelial, epithelial, and macrophage cells. The inhibition of parasite attachment by GAGs was observed with heparin and heparan sulfate and also with chondroitin sulfates, indicating that the ligands for attachment are capable of recognizing a broad range of GAGs. The importance of sulfated proteoglycan recognition was further supported by the demonstration that GAG-deficient mutant host cells, and wild-type cells treated enzymatically to remove GAGs, were partially resistant to parasite invasion. Collectively, these studies reveal that sulfated proteoglycans are one determinant used for substrate and cell recognition by Toxoplasma. The widespread distribution of these receptors may contribute to the broad host and tissue ranges of this highly successful intracellular parasite.
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Affiliation(s)
- V B Carruthers
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri 63110, USA
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