1
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Feng C, Cross AS, Vasta GR. Galectin-1 mediates interactions between polymorphonuclear leukocytes and vascular endothelial cells, and promotes their extravasation during lipopolysaccharide-induced acute lung injury. Mol Immunol 2023; 156:127-135. [PMID: 36921487 PMCID: PMC10154945 DOI: 10.1016/j.molimm.2023.02.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 01/29/2023] [Accepted: 02/26/2023] [Indexed: 03/14/2023]
Abstract
The lung airway epithelial surface is heavily covered with sialic acids as the terminal carbohydrate on most cell surface glycoconjugates and can be removed by microbial neuraminidases or endogenous sialidases. By desialylating the lung epithelial surface, neuraminidase acts as an important virulence factor in many mucosal pathogens, such as influenza and S. pneumoniae. Desialylation exposes the subterminal galactosyl moieties - the binding glycotopes for galectins, a family of carbohydrate-recognition proteins playing important roles in various aspects of immune responses. Galectin-1 and galectin-3 have been extensively studied in their roles related to host immune responses, but some questions about their role(s) in leukocyte recruitment during lung bacterial infection remain unanswered. In this study, we found that both galectin-1 and galectin-3 bind to polymorphonuclear leukocytes (PMNs) and enhance the interaction of endothelial intercellular adhesion molecule-1 (ICAM-1) with PMNs, which is further increased by PMN desialylation. In addition, we observed that in vitro galectin-1 mediates the binding of PMNs, particularly desialylated PMNs, onto the endothelial cells. Finally, in a murine model for LPS-mediated acute lung injury, we observed that galectin-1 modulates PMN infiltration to the lung without altering the expression of chemoattractant cytokines. We conclude that galectins, particularly galectin-1, may function as adhesion molecules that mediate PMN-endothelial cell interactions, and modulate PMN infiltration during acute lung injury.
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Affiliation(s)
- Chiguang Feng
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, USA; Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, USA.
| | - Alan S Cross
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, USA; Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Gerardo R Vasta
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, USA; Institute of Marine and Environmental Technology, University of Maryland, Baltimore, MD, USA
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2
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Howlader MA, Demina EP, Samarani S, Guo T, Caillon A, Ahmad A, Pshezhetsky AV, Cairo CW. The Janus-like role of neuraminidase isoenzymes in inflammation. FASEB J 2022; 36:e22285. [PMID: 35363389 PMCID: PMC9323473 DOI: 10.1096/fj.202101218r] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 02/09/2022] [Accepted: 03/17/2022] [Indexed: 01/13/2023]
Abstract
The processes of activation, extravasation, and migration of immune cells to a site are early and essential steps in the induction of an acute inflammatory response. These events are an essential part of the inflammatory cascade, which involves multiple regulatory steps. Using a murine air pouch model of inflammation with LPS as an inflammation inducer, we demonstrate that isoenzymes of the neuraminidase family (NEU1, 3, and 4) play essential roles in these processes by acting as positive or negative regulators of leukocyte infiltration. In genetically knocked‐out (KO) mice for different NEU genes (Neu1 KO, Neu3 KO, Neu4 KO, and Neu3/4 double KO mice) with LPS‐induced air pouch inflammation, leukocytes at the site of inflammation were counted, and the inflamed tissue was analyzed using immunohistochemistry. Our data show that leukocyte recruitment was decreased in NEU1‐ and NEU3‐deficient mice, while it was increased in NEU4‐deficient animals. Consistent with these results, systemic as well as pouch exudate levels of pro‐inflammatory cytokines were reduced in Neu1 and increased in Neu4 KO mice. Pharmacological inhibitors specific for NEU1, NEU3, and NEU4 isoforms also affected leukocyte recruitment. Together our data demonstrate that NEU isoenzymes have distinct—and even opposing—effects on leukocyte recruitment, and therefore warrant further investigation to determine their mechanisms and importance as regulators of the inflammatory cascade.
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Affiliation(s)
- Md Amran Howlader
- Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada
| | - Ekaterina P Demina
- Division of Medical Genetics, Sainte-Justine Hospital Research Center, University of Montreal, Montreal, Quebec, Canada
| | - Suzanne Samarani
- Department of Microbiology, Infectious Diseases & Immunology, Sainte-Justine Hospital Research Center, University of Montreal, Montreal, Quebec, Canada
| | - Tianlin Guo
- Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada
| | - Antoine Caillon
- Division of Medical Genetics, Sainte-Justine Hospital Research Center, University of Montreal, Montreal, Quebec, Canada
| | - Ali Ahmad
- Department of Microbiology, Infectious Diseases & Immunology, Sainte-Justine Hospital Research Center, University of Montreal, Montreal, Quebec, Canada
| | - Alexey V Pshezhetsky
- Division of Medical Genetics, Sainte-Justine Hospital Research Center, University of Montreal, Montreal, Quebec, Canada.,Department of Anatomy and Cell Biology, McGill University, Montreal, Quebec, Canada
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3
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Wang Y, Pan P, Khan A, Çil Ç, Pineda MA. Synovial Fibroblast Sialylation Regulates Cell Migration and Activation of Inflammatory Pathways in Arthritogenesis. Front Immunol 2022; 13:847581. [PMID: 35371069 PMCID: PMC8971784 DOI: 10.3389/fimmu.2022.847581] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Accepted: 02/28/2022] [Indexed: 12/30/2022] Open
Abstract
Synovial fibroblasts have emerged as critical underlying factors to perpetuate chronic joint inflammation in Rheumatoid Arthritis. Like any other cell, synovial fibroblasts are covered with a complex layer of glycans that can change in response to extracellular signals, such as inflammation. We have previously shown that inflammatory synovial fibroblasts show decreased levels of sialic acid, but our understanding of sialic acid-dependent pathophysiological pathways in these stromal cells is still very limited. In this report, we used in vivo and in vitro studies with exogenous sialidases and RNA sequencing to investigate the responses of murine synovial fibroblasts upon desialylation. Our results show that hyposialylated fibroblasts present a dysregulated migratory ability and an activated phenotype characterized by the expression of inflammatory mediators, such as cytokines and chemokines, and anti-viral related mechanisms. Removal of surface sialic acid also affected the expression of sialyltransferases, revealing the existence of a positive feedback to sustain reduced sialylation. Moreover, we demonstrate that synovial fibroblasts subsets have distinct sialyltransferase expression profiles, both in healthy and arthritic mice. These findings underline the ability of sialic acid to modulate homeostatic and inflammatory responses in non-immune synovial fibroblasts, suggesting that sialylation plays a key role in perpetuating local inflammation in the arthritic joint.
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Affiliation(s)
- Yilin Wang
- Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, United Kingdom
| | - Piaopiao Pan
- Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, United Kingdom
| | - Aneesah Khan
- Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, United Kingdom
| | - Çağlar Çil
- Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, United Kingdom
| | - Miguel A. Pineda
- Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, United Kingdom,Research Into Inflammatory Arthritis Centre Versus Arthritis (RACE), Glasgow, United Kingdom,*Correspondence: Miguel A. Pineda,
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4
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Moons SJ, Rossing E, Janssen MACH, Heise T, Büll C, Adema GJ, Boltje TJ. Structure-Activity Relationship of Metabolic Sialic Acid Inhibitors and Labeling Reagents. ACS Chem Biol 2022; 17:590-597. [PMID: 35179348 PMCID: PMC8938927 DOI: 10.1021/acschembio.1c00868] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
![]()
Sialic acids cap
the glycans of cell surface glycoproteins and
glycolipids. They are involved in a multitude of biological processes,
and aberrant sialic acid expression is associated with several pathologies,
such as cancer. Strategies to interfere with the sialic acid biosynthesis
can potentially be used for anticancer therapy. One well-known class
of sialylation inhibitors is peracetylated 3-fluorosialic acids. We
synthesized 3-fluorosialic acid derivatives modified at the C-4, C-5,
C-8, and C-9 position and tested their inhibitory potency in vitro.
Modifications at C-5 lead to increased inhibition, compared to the
natural acetamide at this position. These structure–activity
relationships could also be applied to improve the efficiency of sialic
acid metabolic labeling reagents by modification of the C-5 position.
Hence, these results improve our understanding of the structure–activity
relationships of sialic acid glycomimetics and their metabolic processing.
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Affiliation(s)
- Sam J. Moons
- Cluster of Molecular Chemistry, Institue for Molecules and Materials, Radboud University Nijmegen, Nijmegen 6525 AJ, The Netherlands
| | - Emiel Rossing
- Cluster of Molecular Chemistry, Institue for Molecules and Materials, Radboud University Nijmegen, Nijmegen 6525 AJ, The Netherlands
| | - Mathilde A. C. H. Janssen
- Cluster of Molecular Chemistry, Institue for Molecules and Materials, Radboud University Nijmegen, Nijmegen 6525 AJ, The Netherlands
| | - Torben Heise
- Cluster of Molecular Chemistry, Institue for Molecules and Materials, Radboud University Nijmegen, Nijmegen 6525 AJ, The Netherlands
| | - Christian Büll
- Department of Biomolecular Chemistry, Institute for Molecules and Materials, Radboud University Nijmegen, Nijmegen 6525 GA, The Netherlands
| | - Gosse J. Adema
- Radiotherapy & OncoImmunology Laboratory, Department of Radiation Oncology, Radboud University Medical Center, Nijmegen 6525 GA, The Netherlands
| | - Thomas J. Boltje
- Cluster of Molecular Chemistry, Institue for Molecules and Materials, Radboud University Nijmegen, Nijmegen 6525 AJ, The Netherlands
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5
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Dou C, Zhen G, Dan Y, Wan M, Limjunyawong N, Cao X. Sialylation of TLR2 initiates osteoclast fusion. Bone Res 2022; 10:24. [PMID: 35232979 PMCID: PMC8888621 DOI: 10.1038/s41413-022-00186-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 09/23/2021] [Accepted: 09/30/2021] [Indexed: 01/24/2023] Open
Abstract
The molecular control of osteoclast formation is still not clearly elucidated. Here, we show that a process of cell recognition mediated by Siglec15-TLR2 binding is indispensable and occurs prior to cell fusion in RANKL-mediated osteoclastogenesis. Siglec15 has been shown to regulate osteoclastic bone resorption. However, the receptor for Siglec15 has not been identified, and the signaling mechanism involving Siglec15 in osteoclast function remains unclear. We found that Siglec15 bound sialylated TLR2 as its receptor and that the binding of sialylated TLR2 to Siglec15 in macrophages committed to the osteoclast-lineage initiated cell fusion for osteoclast formation, in which sialic acid was transferred by the sialyltransferase ST3Gal1. Interestingly, the expression of Siglec15 in macrophages was activated by M-CSF, whereas ST3Gal1 expression was induced by RANKL. Both Siglec15-specific deletion in macrophages and intrafemoral injection of sialidase abrogated cell recognition and reduced subsequent cell fusion for the formation of osteoclasts, resulting in increased bone formation in mice. Thus, our results reveal that cell recognition mediated by the binding of sialylated TLR2 to Siglec15 initiates cell fusion for osteoclast formation.
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Affiliation(s)
- Ce Dou
- grid.21107.350000 0001 2171 9311Department of Orthopedic Surgery, Institute of Cell Engineering and Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD USA
| | - Gehua Zhen
- grid.21107.350000 0001 2171 9311Department of Orthopedic Surgery, Institute of Cell Engineering and Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD USA
| | - Yang Dan
- grid.21107.350000 0001 2171 9311Department of Orthopedic Surgery, Institute of Cell Engineering and Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD USA
| | - Mei Wan
- grid.21107.350000 0001 2171 9311Department of Orthopedic Surgery, Institute of Cell Engineering and Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD USA
| | - Nathachit Limjunyawong
- grid.21107.350000 0001 2171 9311The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD USA
| | - Xu Cao
- grid.21107.350000 0001 2171 9311Department of Orthopedic Surgery, Institute of Cell Engineering and Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD USA
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6
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Balneger N, Cornelissen LAM, Wassink M, Moons SJ, Boltje TJ, Bar-Ephraim YE, Das KK, Søndergaard JN, Büll C, Adema GJ. Sialic acid blockade in dendritic cells enhances CD8 + T cell responses by facilitating high-avidity interactions. Cell Mol Life Sci 2022; 79:98. [PMID: 35089436 PMCID: PMC8799591 DOI: 10.1007/s00018-021-04027-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 10/06/2021] [Accepted: 11/08/2021] [Indexed: 12/11/2022]
Abstract
Sialic acids are negatively charged carbohydrates that cap the glycans of glycoproteins and glycolipids. Sialic acids are involved in various biological processes including cell-cell adhesion and immune recognition. In dendritic cells (DCs), the major antigen-presenting cells of the immune system, sialic acids emerge as important regulators of maturation and interaction with other lymphocytes including T cells. Many aspects of how sialic acids regulate DC functions are not well understood and tools and model systems to address these are limited. Here, we have established cultures of murine bone marrow-derived DCs (BMDCs) that lack sialic acid expression using a sialic acid-blocking mimetic Ac53FaxNeu5Ac. Ac53FaxNeu5Ac treatment potentiated BMDC activation via toll-like receptor (TLR) stimulation without affecting differentiation and viability. Sialic acid blockade further increased the capacity of BMDCs to induce antigen-specific CD8+ T cell proliferation. Transcriptome-wide gene expression analysis revealed that sialic acid mimetic treatment of BMDCs induces differential expression of genes involved in T cell activation, cell-adhesion, and cell-cell interactions. Subsequent cell clustering assays and single cell avidity measurements demonstrated that BMDCs with reduced sialylation form higher avidity interactions with CD8+ T cells. This increased avidity was detectable in the absence of antigens, but was especially pronounced in antigen-dependent interactions. Together, our data show that sialic acid blockade in BMDCs ameliorates maturation and enhances both cognate T cell receptor-MHC-dependent and independent T cell interactions that allow for more robust CD8+ T cell responses.
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Affiliation(s)
- N Balneger
- Radiotherapy and OncoImmunology Laboratory, Department of Radiation Oncology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Geert Grooteplein Zuid 32, 6525 GA, Nijmegen, The Netherlands
| | - L A M Cornelissen
- Radiotherapy and OncoImmunology Laboratory, Department of Radiation Oncology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Geert Grooteplein Zuid 32, 6525 GA, Nijmegen, The Netherlands
| | - M Wassink
- Radiotherapy and OncoImmunology Laboratory, Department of Radiation Oncology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Geert Grooteplein Zuid 32, 6525 GA, Nijmegen, The Netherlands
| | - S J Moons
- Cluster for Molecular Chemistry, Institute for Molecules and Materials, Radboud University Nijmegen, Nijmegen, The Netherlands
| | - T J Boltje
- Cluster for Molecular Chemistry, Institute for Molecules and Materials, Radboud University Nijmegen, Nijmegen, The Netherlands
| | - Y E Bar-Ephraim
- LUMICKS, Pilotenstraat 41, 1059 CH, Amsterdam, The Netherlands
| | - K K Das
- LUMICKS, Pilotenstraat 41, 1059 CH, Amsterdam, The Netherlands
| | - J N Søndergaard
- Center for Infectious Disease Education and Research, Osaka University, Osaka, 565-0871, Japan
| | - C Büll
- Radiotherapy and OncoImmunology Laboratory, Department of Radiation Oncology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Geert Grooteplein Zuid 32, 6525 GA, Nijmegen, The Netherlands
- Hubrecht Institute, Uppsalalaan 8, 3584 CT, Utrecht, The Netherlands
| | - G J Adema
- Radiotherapy and OncoImmunology Laboratory, Department of Radiation Oncology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Geert Grooteplein Zuid 32, 6525 GA, Nijmegen, The Netherlands.
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7
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Neu5Ac Induces Human Dental Pulp Stem Cell Osteo-/Odontoblastic Differentiation by Enhancing MAPK/ERK Pathway Activation. Stem Cells Int 2021; 2021:5560872. [PMID: 34603453 PMCID: PMC8483915 DOI: 10.1155/2021/5560872] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2021] [Revised: 04/26/2021] [Accepted: 08/09/2021] [Indexed: 01/09/2023] Open
Abstract
Dental pulp stem cells (DPSCs) must undergo odontoblastic differentiation in order to facilitate the process of dentin-pulp complex repair. Herein, we sought to explore the ability of Neu5Ac (one form of sialic acid) to influence DPSC osteo-/odontoblastic differentiation via modulating mitogen-activated protein kinase (MAPK) signaling. Methodology. DPSCs were isolated from human third permanent teeth and were grown in vitro. Fluorescent microscopy was used to detect the existence of sialic acid on the DPSC membrane. Following the treatment of different concentrations of Neu5Ac and removing sialic acid from the cell surface by neuraminidase, the osteo-/odontoblastic differentiation of these cells was evaluated via mineralization, alkaline phosphatase, and in vivo assays. In addition, the expression of genes related to osteo-/odontoblastic differentiation and MAPK signaling at different stages of this differentiation process was analyzed in the presence or absence of Neu5Ac. Results. The existence of sialic acid on the DPSC membrane was confirmed by fluorescent microscopy, and the ability of osteo-/odontoblastic differentiation was decreased after removing sialic acid by neuraminidase. Treatment of DPSCs with Neu5Ac (0.1 mM or 1 mM) significantly enhanced their mineralization ability and alkaline phosphatase activity. The expression levels of DMP1, DSPP, BSP, and RUNX2 were also increased. Treatment of nude mice with ManNAc (the prerequisite form of Neu5Ac) also enhanced DPSC mineralization activity in vivo. Furthermore, Neu5Ac treatment enhanced p-ERK expression in DPSCs, while ERK pathway inhibition disrupted the ability of Neu5Ac to enhance the osteo-/odontoblastic differentiation of these cells. Conclusions. Neu5Ac can promote DPSC osteo-/odontoblastic differentiation through a process associated with the modulation of the ERK signaling pathway activity.
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8
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Sialidase of Glaesserella parasuis Augments Inflammatory Response via Desialylation and Abrogation of Negative Regulation of Siglec-5. Infect Immun 2021; 89:IAI.00696-20. [PMID: 33526563 DOI: 10.1128/iai.00696-20] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2020] [Accepted: 01/25/2021] [Indexed: 11/20/2022] Open
Abstract
Siglecs are sialic acid-binding immunoglobulin-like lectins that play an important role in tissue homeostasis, immune response, and pathogen infection. Bacterial sialidases act on natural ligands of Siglecs, interfering with the Siglec-mediated immune response. Glaesserella parasuis is a porcine bacterial pathogen that secretes sialidase. However, little is known about the sialidase of G. parasuis and its impact on immune regulation. Here, we used wild-type G. parasuis, a sialidase-deficient mutant, and complementary strains to investigate the role of sialidase in porcine alveolar macrophage infection. Sialidase induced the release of proinflammatory cytokines, such as interleukin-1α (IL-1α), IL-6, and tumor necrosis factor alpha, from porcine alveolar macrophages. Moreover, sialidase desialylated the surface of porcine alveolar macrophages and altered the expression of Siglecs (the expression of Siglec-5 was reduced). Furthermore, sialidase led to a reduction in endogenous SH2 domain-containing protein tyrosine phosphatase (SHP-2) recruitment to Siglec-5 and simultaneously activated the inflammatory response via the mitogen-activated protein kinase and nuclear factor kappa light chain enhancer of activated B cell signaling pathways. This desialylation occurred before the release of proinflammatory cytokines, suggesting that the sialidase-induced inflammatory response was followed by reduced recruitment of SHP-2 to Siglec-5. Thus, this study is the first to demonstrate the role of sialidase in the inflammatory response of G. parasuis. This role resulted from the abrogation of negative regulation of Siglec-5 on proinflammatory cytokine release. This study helps to understand the molecular mechanism underlying the inflammatory response induced by sialidase secreted by G. parasuis and the acute inflammation caused by G. parasuis.
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9
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Sundararaj K, Rodgers J, Angel P, Wolf B, Nowling TK. The role of neuraminidase in TLR4-MAPK signalling and the release of cytokines by lupus serum-stimulated mesangial cells. Immunology 2021; 162:418-433. [PMID: 33314123 DOI: 10.1111/imm.13294] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 12/03/2020] [Accepted: 12/07/2020] [Indexed: 12/11/2022] Open
Abstract
Previously, we demonstrated neuraminidase (NEU) activity or NEU1 expression, specifically, is increased in the kidneys of lupus mice and urine of human patients with nephritis. Additionally, NEU activity mediates IL-6 secretion from lupus-prone MRL/lpr primary mouse mesangial cells (MCs) in response to an IgG mimic. IL-6 mediates glomerular inflammation and promotes tissue damage in patients and mouse strains with lupus nephritis. This study further elucidates the mechanisms by which NEU activity and NEU1 specifically mediates the release of IL-6 and other cytokines from lupus-prone MCs. We demonstrate significantly increased release of multiple cytokines and NEU activity in MRL/lpr MCs in response to serum from MRL/lpr mice (lupus serum). Inhibiting NEU activity significantly reduced secretion of three of those cytokines: IL-6, GM-CSF and MIP1α. Message levels of Il-6 and Gm-csf were also increased in response to lupus serum and reduced when NEU activity was inhibited. Neutralizing antibodies to cell-surface receptors and MAPK inhibitors in lupus serum- or LPS-stimulated MCs indicate TLR4 and p38 or ERK MAP kinase signalling play key roles in the NEU-mediated secretion of IL-6. Significantly reduced IL-6 release was observed in C57BL/6 (B6) Neu1+/+ primary MCs compared with wild-type (Neu1+/+) B6 MCs in response to lupus serum. Additional results show inhibiting NEU activity significantly increases sialic acid-containing N-glycan levels. Together, our novel observations support a role for NEU activity, and specifically NEU1, in mediating release of IL-6 from lupus-prone MCs in response to lupus serum through a TLR4-p38/ERK MAPK signalling pathway that likely includes desialylation of glycoproteins.
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Affiliation(s)
- Kamala Sundararaj
- Department of Medicine, Division of Rheumatology, Medical University of South Carolina, Charleston, SC, USA
| | - Jessalyn Rodgers
- Department of Medicine, Division of Rheumatology, Medical University of South Carolina, Charleston, SC, USA
| | - Peggi Angel
- Department of Cell and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, Charleston, SC, USA
| | - Bethany Wolf
- Department of Public Health Sciences, Medical University of South Carolina, Charleston, SC, USA
| | - Tamara K Nowling
- Department of Medicine, Division of Rheumatology, Medical University of South Carolina, Charleston, SC, USA
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10
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Holdbrooks AT, Ankenbauer KE, Hwang J, Bellis SL. Regulation of inflammatory signaling by the ST6Gal-I sialyltransferase. PLoS One 2020; 15:e0241850. [PMID: 33166339 PMCID: PMC7652342 DOI: 10.1371/journal.pone.0241850] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Accepted: 10/21/2020] [Indexed: 12/31/2022] Open
Abstract
The ST6Gal-I sialyltransferase, an enzyme that adds α2-6-linked sialic acids to N-glycosylated proteins, regulates multiple immunological processes. However, the contribution of receptor sialylation to inflammatory signaling has been under-investigated. In the current study, we uncovered a role for ST6Gal-I in promoting sustained signaling through two prominent inflammatory pathways, NFκB and JAK/STAT. Using the U937 monocytic cell model, we determined that knockdown (KD) of ST6Gal-I expression had no effect on the rapid activation of NFκB by TNF (≤ 30 min), whereas long-term TNF-induced NFκB activation (2–6 hr) was diminished in ST6Gal-I-KD cells. These data align with prior work in epithelial cells showing that α2–6 sialylation of TNFR1 prolongs TNF-dependent NFκB activation. Similar to TNF, long-term, but not short-term, LPS-induced activation of NFκB was suppressed by ST6Gal-I KD. ST6Gal-I KD cells also exhibited reduced long-term IRF3 and STAT3 activation by LPS. Given that ST6Gal-I activity modulated LPS-dependent signaling, we conducted pull-down assays using SNA (a lectin specific for α2–6 sialic acids) to show that the LPS receptor, TLR4, is a substrate for sialylation by ST6Gal-I. We next assessed signaling by IFNγ, IL-6 and GM-CSF, and found that ST6Gal-I-KD had a limited effect on STAT activation induced by these cytokines. To corroborate these findings, signaling was monitored in bone marrow derived macrophages (BMDMs) from mice with myeloid-specific deletion of ST6Gal-I (LysMCre/ST6Gal-Ifl/fl). In agreement with data from U937 cells, BMDMs with ST6Gal-I knockout displayed reduced long-term activation of NFκB by both TNF and LPS, and diminished long-term LPS-dependent STAT3 activation. However, STAT activation induced by IFNγ, IL-6 and GM-CSF was comparable in wild-type and ST6Gal-I knockout BMDMs. These results implicate ST6Gal-I-mediated receptor sialylation in prolonging the activity of select signaling cascades including TNF/NFκB, LPS/NFκB, and LPS/STAT3, providing new insights into ST6Gal-I’s role in modulating the inflammatory phenotype of monocytic cells.
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Affiliation(s)
- Andrew T Holdbrooks
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL, United States of America
| | - Katherine E Ankenbauer
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL, United States of America
| | - Jihye Hwang
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL, United States of America
| | - Susan L Bellis
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL, United States of America
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11
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Heimerl M, Sieve I, Ricke-Hoch M, Erschow S, Battmer K, Scherr M, Hilfiker-Kleiner D. Neuraminidase-1 promotes heart failure after ischemia/reperfusion injury by affecting cardiomyocytes and invading monocytes/macrophages. Basic Res Cardiol 2020; 115:62. [PMID: 32975669 PMCID: PMC7519006 DOI: 10.1007/s00395-020-00821-z] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Accepted: 09/01/2020] [Indexed: 12/31/2022]
Abstract
Neuraminidase (NEU)1 forms a multienzyme complex with beta-galactosidase (β-GAL) and protective-protein/cathepsin (PPC) A, which cleaves sialic-acids from cell surface glycoconjugates. We investigated the role of NEU1 in the myocardium after ischemia/reperfusion (I/R). Three days after inducing I/R, left ventricles (LV) of male mice (3 months-old) displayed upregulated neuraminidase activity and increased NEU1, β-GAL and PPCA expression. Mice hypomorphic for neu1 (hNEU1) had less neuraminidase activity, fewer pro-inflammatory (Lin−CD11b+F4/80+Ly-6Chigh), and more anti-inflammatory macrophages (Lin−CD11b+F4/80+Ly-6Clow) 3 days after I/R, and less LV dysfunction 14 days after I/R. WT mice transplanted with hNEU1-bone marrow (BM) and hNEU1 mice with WT-BM showed significantly better LV function 14 days after I/R compared with WT mice with WT-BM. Mice with a cardiomyocyte-specific NEU1 overexpression displayed no difference in inflammation 3 days after I/R, but showed increased cardiomyocyte hypertrophy, reduced expression and mislocalization of Connexin-43 in gap junctions, and LV dysfunction despite a similar infarct scar size to WT mice 14 days after I/R. The upregulation of NEU1 after I/R contributes to heart failure by promoting inflammation in invading monocytes/macrophages, enhancing cardiomyocyte hypertrophy, and impairing gap junction function, suggesting that systemic NEU1 inhibition may reduce heart failure after I/R.
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Affiliation(s)
- Maren Heimerl
- Molecular Cardiology, Department of Cardiology and Angiology, Hannover Medical School, Carl-Neuberg Str. 1, 30625, Hannover, Germany
| | - Irina Sieve
- Molecular Cardiology, Department of Cardiology and Angiology, Hannover Medical School, Carl-Neuberg Str. 1, 30625, Hannover, Germany
| | - Melanie Ricke-Hoch
- Molecular Cardiology, Department of Cardiology and Angiology, Hannover Medical School, Carl-Neuberg Str. 1, 30625, Hannover, Germany
| | - Sergej Erschow
- Molecular Cardiology, Department of Cardiology and Angiology, Hannover Medical School, Carl-Neuberg Str. 1, 30625, Hannover, Germany
| | - Karin Battmer
- Department of Hematology, Hemostasis, Oncology and Stem Cell Transplantation, Hannover Medical School, Carl-Neuberg-Str.1, 30625, Hannover, Germany
| | - Michaela Scherr
- Department of Hematology, Hemostasis, Oncology and Stem Cell Transplantation, Hannover Medical School, Carl-Neuberg-Str.1, 30625, Hannover, Germany
| | - Denise Hilfiker-Kleiner
- Molecular Cardiology, Department of Cardiology and Angiology, Hannover Medical School, Carl-Neuberg Str. 1, 30625, Hannover, Germany.
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Karmakar J, Roy S, Mandal C. Modulation of TLR4 Sialylation Mediated by a Sialidase Neu1 and Impairment of Its Signaling in Leishmania donovani Infected Macrophages. Front Immunol 2019; 10:2360. [PMID: 31649671 PMCID: PMC6794462 DOI: 10.3389/fimmu.2019.02360] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Accepted: 09/19/2019] [Indexed: 12/12/2022] Open
Abstract
Altered sialylation is generally maintained by a fine balance between sialidases and sialyltransferases, which plays an essential role during disease pathogenesis. TLR4 is a membrane-bound highly sialylated glycoprotein predominantly having α2,3-linked sialic acids. It is one of the most important client molecules in the anti-leishmanial innate immune arm. Here, we initiated a comprehensive study on the modulation of TLR4 sialylation in Leishmania donovani (L. d)-infected macrophages by a mammalian sialidase/neuraminidase-1 (Neu1) having substrate specificity toward α2,3-linked sialic acids. We observed reduced membrane-associated Neu1 with its decreased enzyme activity in infected macrophages. Moreover, we demonstrated reduced association of Neu1 with TLR4 leading to enhanced sialylation of TLR4 in these infected cells. Conversely, Neu1 over expression exhibited enhanced association of TLR4 with Neu1 leading to reduced sialylation which possibly linked to increased association of TLR4 with its downstream adaptor protein, MyD88. This, in turn, activated downstream MAP kinase signaling pathway, with enhanced nuclear translocation of NFκB that resulted in increased genetic and protein levels expression of Th1 cytokines and effector molecule nitric oxide secretion which ultimately leads to reduced parasite burden in macrophages. This was further validated by Neu1 silencing in infected macrophages which reversed such a situation. Such events strongly confirm the importance of Neu1 in modulation of TLR4 sialylation during parasite infection resulting in impairment of innate immune response. Furthermore, decreased membrane-bound Neu1 in infected macrophages could be attributed to its reduced tyrosine-phosphorylation as well as diminished association with cathepsin A. Both these phenomenon possibly play significant roles in inhibiting translocation of the sialidase from cytosol to membrane. Taken together, our study first time demonstrated impaired translocation of cytosolic Neu1 to the membrane of L. donovani-infected macrophages due to impaired phosphorylation of this enzyme. This novel finding establishes a link between enhanced α2,3-linked sialic acids on TLR4 and reduced membrane-bound Neu1 which plays a significant role for inhibiting downstream signaling to establish successful infection in the host cells.
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Affiliation(s)
- Joyshree Karmakar
- Cancer Biology and Inflammatory Disorder Division, CSIR-Indian Institute of Chemical Biology, Kolkata, India
| | - Saptarshi Roy
- Cancer Biology and Inflammatory Disorder Division, CSIR-Indian Institute of Chemical Biology, Kolkata, India
| | - Chitra Mandal
- Cancer Biology and Inflammatory Disorder Division, CSIR-Indian Institute of Chemical Biology, Kolkata, India
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Wei M, Wang PG. Desialylation in physiological and pathological processes: New target for diagnostic and therapeutic development. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2019; 162:25-57. [PMID: 30905454 DOI: 10.1016/bs.pmbts.2018.12.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Desialylation is a pivotal part of sialic acid metabolism, which initiates the catabolism of glycans by removing the terminal sialic acid residues on glycans, thereby modulating the structure and functions of glycans, glycoproteins, or glycolipids. The functions of sialic acids have been well recognized, whereas the function of desialylation process is underappreciated or largely ignored. However, accumulating evidence demonstrates that desialylation plays an important role in a variety of physiological and pathological processes. This chapter summarizes the current knowledge pertaining to desialylation in a variety of physiological and pathological processes, with a focus on the underlying molecular mechanisms. The potential of targeting desialylation process for diagnostic and therapeutic development is also discussed.
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Affiliation(s)
- Mohui Wei
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States.
| | - Peng George Wang
- Department of Chemistry, Center for Diagnostics and Therapeutics, Georgia State University, Atlanta, GA, United States
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Xue Z, Zhao H, Zhu R, Chen C, Cao H, Han J, Han S. On the use of abiotic sialic acids to attenuate cell inflammation. Sci Rep 2018; 8:17320. [PMID: 30470771 PMCID: PMC6251910 DOI: 10.1038/s41598-018-35477-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Accepted: 11/06/2018] [Indexed: 01/22/2023] Open
Abstract
Sialic acid (Sia) residues on cell surface are critical for myriad cellular events such as immunity and inflammation. We herein reported the use of abiotic Sia to raise the thresholds of inflammatory cell responses. Identified from a panel of structurally diversified Sia analogs via a cell inflammation assay, Sia-2, with N-butyryl moiety at C-5, markedly lowered LPS-stimulated NF-κB activity in macrophages. Further analysis shows that Sia-2 attenuates phosphorylation of IκB and Erk1/2/p38/JNK, critical for NF-κB signaling and MAPK signaling, and lowers gene transcription of proinflammatory interleukin-6. These results support the use of abiotic Sia as promising agents to modulate cell surface Sia-pertinent cell signaling.
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Affiliation(s)
- Zhongwei Xue
- Department of Chemical Biology, College of Chemistry and Chemical Engineering, State Key Laboratory for Physical Chemistry of Solid Surfaces, the Key Laboratory for Chemical Biology of Fujian Province, The MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, and Innovation Center for Cell Biology, Xiamen University, Xiamen, 361005, China
| | - Hu Zhao
- Department of Chemical Biology, College of Chemistry and Chemical Engineering, State Key Laboratory for Physical Chemistry of Solid Surfaces, the Key Laboratory for Chemical Biology of Fujian Province, The MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, and Innovation Center for Cell Biology, Xiamen University, Xiamen, 361005, China
| | - Rui Zhu
- Department of Chemical Biology, College of Chemistry and Chemical Engineering, State Key Laboratory for Physical Chemistry of Solid Surfaces, the Key Laboratory for Chemical Biology of Fujian Province, The MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, and Innovation Center for Cell Biology, Xiamen University, Xiamen, 361005, China
| | - Congcong Chen
- National Glycoengineering research center, Shandong University, Jinan, 250012, China
| | - Hongzhi Cao
- National Glycoengineering research center, Shandong University, Jinan, 250012, China
| | - Jiahuai Han
- State key Laboratory of Cellular Stress Biology, Innovation Center for Cell Biology, School of Life Sciences, Xiamen University, Xiamen, 361005, China
| | - Shoufa Han
- Department of Chemical Biology, College of Chemistry and Chemical Engineering, State Key Laboratory for Physical Chemistry of Solid Surfaces, the Key Laboratory for Chemical Biology of Fujian Province, The MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, and Innovation Center for Cell Biology, Xiamen University, Xiamen, 361005, China.
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Cambeiro-Pérez N, Hidalgo-Cantabrana C, Moro-García MA, Alonso-Arias R, Simal-Gándara J, Sánchez B, Martínez-Carballo E. A Metabolomics Approach Reveals Immunomodulatory Effects of Proteinaceous Molecules Derived From Gut Bacteria Over Human Peripheral Blood Mononuclear Cells. Front Microbiol 2018; 9:2701. [PMID: 30524384 PMCID: PMC6262353 DOI: 10.3389/fmicb.2018.02701] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Accepted: 10/23/2018] [Indexed: 01/24/2023] Open
Abstract
There are strong evidences that probiotics influence the immune status of the host, in a strain-specific manner, acting in the gastrointestinal tract. On the hypothesis that certain extracellular proteins and peptides from gut bacteria may mediate part of this immunomodulation and assuming they are able to diffuse through the mucus layer and interact with immune cells we have developed this work. Our study attempts to understand the immunomodulatory mechanisms of (i) Pext, the extracellular protein fraction of Lactobacillus acidophilus DSM20079T, (ii) HM14, a peptide encrypted in an extracellular glycoside hydrolase from Bifidobacterium longum NCIMB 8809 and (iii) Escherichia coli O111:B4 lipopolysaccharide (LPS), a well-known pro-inflammatory molecule, over human peripheral blood mononuclear cells (PBMCs). An untargeted LC-ESI-QTOF-MS metabolomics approach was applied to reveal intracellular changes in treated-PBMCs isolated from healthy donors. Differences in NADH arrest, NAD+ concentration reduction, as well as increases in palmitic acid and methanephrin were observed in HM14 and Pext treated-cells compared to those stimulated with LPS. This would support an anti-inflammatory molecular mechanism of action of such proteinaceous molecules. Moreover, this methodology has confirms the importance of metabolomics approaches to better understanding immune cell responses to gut bacterial-derived molecules.
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Affiliation(s)
- Noelia Cambeiro-Pérez
- Nutrition and Bromatology Group, Department of Analytical and Food Chemistry, Faculty of Food Science, University of Vigo, Ourense, Spain
| | - Claudio Hidalgo-Cantabrana
- Department of Microbiology and Biochemistry of Dairy Products, Instituto de Productos Lácteos de Asturias, Consejo Superior de Investigaciones Científicas, Villaviciosa, Spain.,Department of Immunology, Hospital Universitario Central de Asturias, Oviedo, Spain
| | - Marco A Moro-García
- Department of Microbiology and Biochemistry of Dairy Products, Instituto de Productos Lácteos de Asturias, Consejo Superior de Investigaciones Científicas, Villaviciosa, Spain.,Department of Immunology, Hospital Universitario Central de Asturias, Oviedo, Spain
| | - Rebeca Alonso-Arias
- Department of Immunology, Hospital Universitario Central de Asturias, Oviedo, Spain
| | - Jesús Simal-Gándara
- Nutrition and Bromatology Group, Department of Analytical and Food Chemistry, Faculty of Food Science, University of Vigo, Ourense, Spain
| | - Borja Sánchez
- Department of Microbiology and Biochemistry of Dairy Products, Instituto de Productos Lácteos de Asturias, Consejo Superior de Investigaciones Científicas, Villaviciosa, Spain
| | - Elena Martínez-Carballo
- Nutrition and Bromatology Group, Department of Analytical and Food Chemistry, Faculty of Food Science, University of Vigo, Ourense, Spain
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Susceptibility of airways to Pseudomonas aeruginosa infection: mouse neuraminidase model. MONATSHEFTE FUR CHEMIE 2017. [DOI: 10.1007/s00706-017-2035-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Antibody against Microbial Neuraminidases Recognizes Human Sialidase 3 (NEU3): the Neuraminidase/Sialidase Superfamily Revisited. mBio 2017; 8:mBio.00078-17. [PMID: 28655817 PMCID: PMC5487728 DOI: 10.1128/mbio.00078-17] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Neuraminidases (NAs) are critical virulence factors for several microbial pathogens. With a highly conserved catalytic domain, a microbial NA "superfamily" has been proposed. We previously reported that murine polymorphonuclear leukocyte (PMN) sialidase activity was important in leukocyte trafficking to inflamed sites and that antibodies to Clostridium perfringens NA recognized a cell surface molecule(s), presumed to be a sialidase of eukaryotic origin on interleukin-8-stimulated human and murine PMNs. These antibodies also inhibited cell sialidase activity both in vitro and, in the latter instance, in vivo We therefore hypothesized that mammalian sialidases share structural homology and epitopes with microbial NAs. We now report that antibodies to one of the isoforms of C. perfringens NA, as well as anti-influenza virus NA serum, recognize human NEU3 but not NEU1 and that antibodies to C. perfringens NA inhibit NEU3 enzymatic activity. We conclude that the previously described microbial NA superfamily extends to human sialidases. Strategies designed to therapeutically inhibit microbial NA may need to consider potential compromising effects on human sialidases, particularly those expressed in cells of the immune system.IMPORTANCE We previously reported that sialidase activity of human neutrophils plays a critical role in the host inflammatory response. Since the catalytic domains of microbial neuraminidases are highly conserved, we hypothesized that antibodies against Clostridium perfringens neuraminidase might inhibit mammalian sialidase activity. Before the recognition of four mammalian sialidase (Neu) isoforms, we demonstrated that anti-C. perfringens neuraminidase antibodies inhibited human and murine sialidase activity in vivo and in vitro We now show that the antibodies to microbial neuraminidase (C. perfringens and influenza virus) recognize human NEU3, which is important for neural development and cell signaling. Since many microbes that infect mucosal surfaces express neuraminidase, it is possible that the use of sialidase inhibitors (e.g., zanamivir), might also compromise human sialidase activity critical to the human immune response. Alternatively, sialidase inhibitors may prove useful in the treatment of hyperinflammatory conditions.
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18
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Metabolic sialic acid blockade lowers the activation threshold of moDCs for TLR stimulation. Immunol Cell Biol 2016; 95:408-415. [PMID: 27874015 DOI: 10.1038/icb.2016.105] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Revised: 09/27/2016] [Accepted: 10/13/2016] [Indexed: 12/29/2022]
Abstract
Sialic acid sugars cover the surface of dendritic cells (DCs) and have been suggested to impact several aspects of DC biology. Research into the role of sialic acids in DCs, however, is complicated by the limited number of tools available to modulate sialic acid expression. Here we report on a synthetic, fluorinated sialic acid mimetic, Ac53FaxNeu5Ac, which potently blocks sialic acid expression in human monocyte-derived DCs (moDCs). Sialic acid blockade enhanced the responsiveness of moDCs to Toll-like receptor (TLR) stimulation as measured by increased maturation marker expression and cytokine production. Consequently, the T-cell activation capacity of Ac53FaxNeu5Ac-treated moDCs was strongly increased. In addition to sialic acids, moDCs also expressed the sialic acid-binding immunoglobulin-like lectins (Siglecs) -3, -5, -7, -9 and -10, immune inhibitory receptors recognizing these sialic acids. Treatment with Ac53FaxNeu5Ac abrogated putative cis and trans interactions between sialic acids and Siglec-7/-9. Together, these data indicate that sialic acids limit the activation of moDCs via the TLR pathway, potentially by interacting with Siglec-7 or Siglec-9. Metabolic sialic acid blockade with Ac53FaxNeu5Ac could therefore potentially be used to generate more potent DC-based vaccines for induction of robust anti-viral or anti-tumor immune responses.
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19
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Woodman Z. Can one size fit all? Approach to bacterial vaginosis in sub-Saharan Africa. Ann Clin Microbiol Antimicrob 2016; 15:16. [PMID: 26968525 PMCID: PMC4787044 DOI: 10.1186/s12941-016-0132-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Accepted: 03/02/2016] [Indexed: 01/06/2023] Open
Abstract
Bacterial vaginosis (BV) is the most common vaginal disorder affecting women of reproductive age and is associated with increased risk of sexually transmitted infections such as human immunodeficiency syndrome (HIV-1). Sub-Saharan Africa has the highest BV and HIV-1 burden and yet very few studies have focused on understanding the aetiology of BV and its association with HIV in this region. It has been suggested that we need to accurately diagnose and treat BV to lower the risk of HIV infection globally. However, effective diagnosis requires knowledge of what constitutes a "healthy" cervicovaginal microbiome and current studies indicate that Lactobacillus crispatus might not be the only commensal protective against BV: healthy women from different countries and ethnicities harbour alternative commensals. Microbiotas associated with BV have also shown global variation, further complicating effective diagnosis via culture-based assays as some species are difficult to grow. Antibiotics and probiotics have been suggested to be key in controlling BV infection, but the efficacy of this treatment might rely on reconstituting endogenous commensals while targeting a specific species of BV-associated bacteria (BVAB). Alternatively, therapy could inhibit essential BV bacterial growth factors e.g. sialidases or provide anti-microbial compounds e.g. lactic acid associated with a healthy cervicovaginal microbiome. But without global investigation into the mechanism of BV pathogenesis and its association with HIV, selection of such compounds could be limited to Caucasian women from certain regions. To confirm this suggestion and guide future therapy we require standardised diagnostic assays and research methodologies. This review will focus on research papers that describe the global variation of BV aetiology and how this influences the identification of determinants of BV pathogenesis and potential probiotic and antimicrobial therapy.
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Affiliation(s)
- Zenda Woodman
- Department of Molecular and Cell Biology, University of Cape Town, Rondebosch, Cape Town, South Africa.
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20
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Argirova R, Nenova R, Ivanov D, Genova-Kalou P, Raleva S. Experimental model to study co-infection of human immunodeficiency virus-type 1 (HIV-1 IIIB) and influenza virus in cell culture. BIOTECHNOL BIOTEC EQ 2016. [DOI: 10.1080/13102818.2015.1091273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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21
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Álvarez B, Escalona Z, Uenishi H, Toki D, Revilla C, Yuste M, Del Moral MG, Alonso F, Ezquerra A, Domínguez J. Molecular and functional characterization of porcine Siglec-3/CD33 and analysis of its expression in blood and tissues. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2015; 51:238-250. [PMID: 25892023 DOI: 10.1016/j.dci.2015.04.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Revised: 04/08/2015] [Accepted: 04/09/2015] [Indexed: 06/04/2023]
Abstract
A cDNA clone encoding a 380 a-a type 1 transmembrane protein with homology to human Siglec-3/CD33 was obtained from a swine small intestine library. An analysis of protein sequence identified two immunoglobulin-like domains, a transmembrane region, and a carboxi-terminal tail with two tyrosine-based signalling motifs. Binding assays of Siglec-3 transfected CHO cells to polyacrylamide glycoconjugates showed a preference for α2-6-linked sialic acids. Using mAbs raised against a fragment containing the two Ig-like domains, porcine Siglec-3 was found to be expressed on monocytes and granulocytes, and their bone marrow precursors. It was also detected in lymph node, splenic and alveolar macrophages. MAbs immunoprecipitated, from granulocyte lysates, a protein of 51-60 kDa under both non-reducing and reducing conditions. MAbs were also used to analyse functional activity of Siglec-3 on bone marrow and blood cells. Engagement of Siglec-3 by mAb had no apparent effect on cell proliferation or cytokine production.
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Affiliation(s)
- B Álvarez
- Dpto. de Biotecnología, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Ctra de la Coruña Km 7.5, Madrid 28040, Spain
| | - Z Escalona
- Dpto. de Biotecnología, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Ctra de la Coruña Km 7.5, Madrid 28040, Spain
| | - H Uenishi
- National Institute of Agrobiological Sciences (NIAS), 2 Ikenodai, Tsukuba, Ibaraki 305-8602, Japan
| | - D Toki
- Institute of Japan Association for Techno-innovation in Agriculture, Forestry and Fisheries, 446-1 Ippaizuka, Kamiyokoba, Tsukuba, Ibaraki 305-0854, Japan
| | - C Revilla
- Dpto. de Biotecnología, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Ctra de la Coruña Km 7.5, Madrid 28040, Spain
| | - M Yuste
- Dpto. de Biotecnología, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Ctra de la Coruña Km 7.5, Madrid 28040, Spain
| | - M Gómez Del Moral
- Dpto. de Biología Celular y de Inmunología, Facultad de Medicina, Universidad Complutense de Madrid, Avda. Complutense s/n, Madrid 28040, Spain
| | - F Alonso
- Dpto. de Biotecnología, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Ctra de la Coruña Km 7.5, Madrid 28040, Spain
| | - A Ezquerra
- Dpto. de Biotecnología, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Ctra de la Coruña Km 7.5, Madrid 28040, Spain
| | - J Domínguez
- Dpto. de Biotecnología, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Ctra de la Coruña Km 7.5, Madrid 28040, Spain.
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22
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Impact of bacterial vaginosis, as assessed by nugent criteria and hormonal status on glycosidases and lectin binding in cervicovaginal lavage samples. PLoS One 2015; 10:e0127091. [PMID: 26011704 PMCID: PMC4444347 DOI: 10.1371/journal.pone.0127091] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Accepted: 04/10/2015] [Indexed: 11/19/2022] Open
Abstract
The objective of this study was to evaluate the impact of hormonal status and bacterial vaginosis (BV) on the glycosidases present and glycosylation changes as assessed by lectin binding to cervicovaginal lavage constituents. Frozen cervicovaginal lavage samples from a completed study examining the impact of reproductive hormones on the physicochemical properties of vaginal fluid were utilized for the present study. In the parent study, 165 women were characterized as having BV, intermediate or normal microflora using the Nugent criteria. The presence of glycosidases in the samples was determined using quantitative 4-methyl-umbelliferone based assays, and glycosylation was assessed using enzyme linked lectin assays (ELLA). Women with BV had elevated sialidase, α-galactosidase, β-galactosidase and α-glucosidase activities compared to intermediate or normal women (P<0.001, 0.003, 0.006 and 0.042 respectively). The amount of sialic acid (Sambucus nigra, P = 0.003) and high mannose (griffithsin, P<0.001) were reduced, as evaluated by lectin binding, in women with BV. When the data were stratified according to hormonal status, α-glucosidase and griffithsin binding were decreased among postmenopausal women (P<0.02) when compared to premenopausal groups. These data suggest that both hormonal status and BV impact the glycosidases and lectin binding sites present in vaginal fluid. The sialidases present at increased levels in women with BV likely reduce the number of sialic acid binding sites. Other enzymes likely reduce griffithsin binding. The alterations in the glycosidase content, high mannose and sialic acid binding sites in the cervicovaginal fluid associated with bacterial vaginosis may impact susceptibility to viruses, such as HIV, that utilize glycans as a portal of entry.
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Feng C, Zhang L, Nguyen C, Vogel SN, Goldblum SE, Blackwelder WC, Cross AS. Neuraminidase reprograms lung tissue and potentiates lipopolysaccharide-induced acute lung injury in mice. THE JOURNAL OF IMMUNOLOGY 2013; 191:4828-37. [PMID: 24068662 DOI: 10.4049/jimmunol.1202673] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We previously reported that removal of sialyl residues primed PBMCs to respond to bacterial LPS stimulation in vitro. Therefore, we speculated that prior desialylation can sensitize the host to generate an enhanced inflammatory response upon exposure to a TLR ligand, such as LPS, in a murine model of acute lung injury. Intratracheal instillation of neuraminidase (NA) 30 min prior to intratracheal administration of LPS increased polymorphonuclear leukocytes (PMNs) in the bronchoalveolar lavage fluid and the wet-to-dry lung weight ratio, a measure of pulmonary edema, compared with mice that received LPS alone. Administration of NA alone resulted in desialylation of bronchiolar and alveolar surfaces and induction of TNF-α, IL-1β, and chemokines in lung homogenates and bronchoalveolar lavage fluid; however, PMN recruitment in mice treated with NA alone did not differ from that of PBS-administered controls. NA pretreatment alone induced apoptosis and markedly enhanced LPS-induced endothelial apoptosis. Administration of recombinant Bcl-2, an antiapoptotic molecule, abolished the effect of NA treatment on LPS-induced PMN recruitment and pulmonary edema formation. We conclude that NA pretreatment potentiates LPS-induced lung injury through enhanced PMN recruitment, pulmonary edema formation, and endothelial and myeloid cell apoptosis. A similar "reprogramming" of immune responses with desialylation may occur during respiratory infection with NA-expressing microbes and contribute to severe lung injury.
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Affiliation(s)
- Chiguang Feng
- Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, MD 21201
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Cabral MG, Silva Z, Ligeiro D, Seixas E, Crespo H, Carrascal MA, Silva M, Piteira AR, Paixão P, Lau JT, Videira PA. The phagocytic capacity and immunological potency of human dendritic cells is improved by α2,6-sialic acid deficiency. Immunology 2013; 138:235-45. [PMID: 23113614 DOI: 10.1111/imm.12025] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2012] [Revised: 10/17/2012] [Accepted: 10/22/2012] [Indexed: 12/22/2022] Open
Abstract
Dendritic cells (DCs) play an essential role in immunity against bacteria by phagocytosis and by eliciting adaptive immune responses. Previously, we demonstrated that human monocyte-derived DCs (MDDCs) express a high content of cell surface α2,6-sialylated glycans. However, the relative role of these sialylated structures in phagocytosis of bacteria has not been reported. Here, we show that treatment with a sialidase significantly improved the capacity of both immature and mature MDDCs to phagocytose Escherichia coli. Desialylated MDDCs had a significantly more mature phenotype, with higher expression of MHC molecules and interleukin (IL)-12, tumour necrosis factor-α, IL-6 and IL-10 cytokines, and nuclear factor-κB activation. T lymphocytes primed by desialylated MDDCs expressed more interferon-γ when compared with priming by sialylated MDDCs. Improved phagocytosis required E. coli sialic acids, indicating a mechanism of host-pathogen interaction dependent on sialic acid moieties. The DCs harvested from mice deficient in the ST6Gal.1 sialyltransferase showed improved phagocytosis capacity, demonstrating that the observed sialidase effect was a result of the removal of α2,6-sialic acid. The phagocytosis of different pathogenic E. coli isolates was also enhanced by sialidase, which suggests that modifications on MDDC sialic acids may be considered in the development of MDDC-based antibacterial therapies. Physiologically, our findings shed new light on mechanisms that modulate the function of both immature and mature MDDCs, in the context of host-bacteria interaction. Hence, with particular relevance to DC-based therapies, the engineering of α2,6-sialic acid cell surface is a novel possibility to fine tune DC phagocytosis and immunological potency.
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Affiliation(s)
- M Guadalupe Cabral
- CEDOC, Faculdade de Ciências Médicas, Universidade Nova de Lisboa, Lisboa, Portugal
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Immunoproteomic analysis of the protective response obtained with subunit and commercial vaccines against Glässer's disease in pigs. Vet Immunol Immunopathol 2013; 151:235-47. [DOI: 10.1016/j.vetimm.2012.11.014] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2012] [Revised: 11/19/2012] [Accepted: 11/26/2012] [Indexed: 10/27/2022]
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Feng C, Stamatos NM, Dragan AI, Medvedev A, Whitford M, Zhang L, Song C, Rallabhandi P, Cole L, Nhu QM, Vogel SN, Geddes CD, Cross AS. Sialyl residues modulate LPS-mediated signaling through the Toll-like receptor 4 complex. PLoS One 2012; 7:e32359. [PMID: 22496731 PMCID: PMC3322133 DOI: 10.1371/journal.pone.0032359] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2011] [Accepted: 01/26/2012] [Indexed: 11/19/2022] Open
Abstract
We previously reported that neuraminidase (NA) pretreatment of human PBMCs markedly increased their cytokine response to lipopolysaccharide (LPS). To study the mechanisms by which this occurs, we transfected HEK293T cells with plasmids encoding TLR4, CD14, and MD2 (three components of the LPS receptor complex), as well as a NFκB luciferase reporting system. Both TLR4 and MD2 encoded by the plasmids are α-2,6 sialylated. HEK293T cells transfected with TLR4/MD2/CD14 responded robustly to the addition of LPS; however, omission of the MD2 plasmid abrogated this response. Addition of culture supernatants from MD2 (sMD2)-transfected HEK293T cells, but not recombinant, non-glycosylated MD2 reconstituted this response. NA treatment of sMD2 enhanced the LPS response as did NA treatment of the TLR4/CD14-transfected cell supplemented with untreated sMD2, but optimal LPS-initiated responses were observed with NA-treated TLR4/CD14-transfected cells supplemented with NA-treated sMD2. We hypothesized that removal of negatively charged sialyl residues from glycans on the TLR4 complex would hasten the dimerization of TLR4 monomers required for signaling. Co-transfection of HEK293T cells with separate plasmids encoding either YFP- or FLAG-tagged TLR4, followed by treatment with NA and stimulation with LPS, led to an earlier and more robust time-dependent dimerization of TLR4 monomers on co-immunoprecipitation, compared to untreated cells. These findings were confirmed by fluorescence resonance energy transfer (FRET) analysis. Overexpression of human Neu1 increased LPS-initiated TLR4-mediated NFκB activation and a NA inhibitor suppressed its activation. We conclude that (1) sialyl residues on TLR4 modulate LPS responsiveness, perhaps by facilitating clustering of the homodimers, and that (2) sialic acid, and perhaps other glycosyl species, regulate MD2 activity required for LPS-mediated signaling. We speculate that endogenous sialidase activity mobilized during cell activation may play a role in this regulation.
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Affiliation(s)
- Chiguang Feng
- Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Nicholas M. Stamatos
- Institute of Human Virology and Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Anatoliy I. Dragan
- Institute of Fluorescence, University of Maryland, Baltimore County, Baltimore, Maryland, United States of America
| | - Andrei Medvedev
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Melissa Whitford
- Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Lei Zhang
- Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Chang Song
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Prasad Rallabhandi
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Leah Cole
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Quan M. Nhu
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Stefanie N. Vogel
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Chris D. Geddes
- Institute of Fluorescence, University of Maryland, Baltimore County, Baltimore, Maryland, United States of America
| | - Alan S. Cross
- Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
- * E-mail:
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Jellusova J, Nitschke L. Regulation of B cell functions by the sialic acid-binding receptors siglec-G and CD22. Front Immunol 2012; 2:96. [PMID: 22566885 PMCID: PMC3342095 DOI: 10.3389/fimmu.2011.00096] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2011] [Accepted: 12/28/2011] [Indexed: 01/08/2023] Open
Abstract
B cell antigen receptor (BCR) engagement can lead to many different physiologic outcomes. To achieve an appropriate response, the BCR signal is interpreted in the context of other stimuli and several additional receptors on the B cell surface participate in the modulation of the signal. Two members of the Siglec (sialic acid-binding immunoglobulin-like lectin) family, CD22 and Siglec-G have been shown to inhibit the BCR signal. Recent findings indicate that the ability of these two receptors to bind sialic acids might be important to induce tolerance to self-antigens. Sialylated glycans are usually absent on microbes but abundant in higher vertebrates and might therefore provide an important tolerogenic signal. Since the expression of the specific ligands for Siglec-G and CD22 is tightly regulated and since Siglecs are not only able to bind their ligands in trans but also on the same cell surface this might provide additional mechanisms to control the BCR signal. Although both Siglec-G and CD22 are expressed on B cells and are able to inhibit BCR mediated signaling, they also show unique biological functions. While CD22 is the dominant regulator of calcium signaling on conventional B2 cells and also seems to play a role on marginal zone B cells, Siglec-G exerts its function mainly on B1 cells and influences their lifespan and antibody production. Both Siglec-G and CD22 have also recently been linked to toll-like receptor signaling and may provide a link in the regulation of the adaptive and innate immune response of B cells.
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Abstract
Cell surface expression of sialic acid has been reported to decrease during immune cell activation, but the significance and regulation of this phenomenon are still being investigated. The major human bacterial pathogen Streptococcus pneumoniae causes pneumonia, sepsis and meningitis, often accompanied by strong inflammatory responses. S. pneumoniae expresses a sialidase (NanA) that contributes to mucosal colonization, platelet clearance, and blood-brain barrier penetration. Using wild-type and isogenic NanA-deficient mutant strains, we showed that S. pneumoniae NanA can desialylate the surface of human THP-1 monocytes, leading to increased ERK phosphorylation, NF-κB activation, and proinflammatory cytokine release. S. pneumoniae NanA expression also stimulates interleukin-8 release and extracellular trap formation from human neutrophils. A mechanistic contribution of unmasking of inhibitory Siglec-5 from cis sialic acid interactions to the proinflammatory effect of NanA is suggested by decreased SHP-2 recruitment to the Siglec-5 intracellular domain and RNA interference studies. Finally, NanA increased production of proinflammatory cytokines in a murine intranasal challenge model of S. pneumoniae pneumonia. Importance Sialic acids decorate the surface of all mammalian cells and play important roles in physiology, development, and evolution. Siglecs are sialic acid-binding receptors on the surface of immune cells, many of which engage in cis interactions with host sialoglycan ligands and dampen inflammatory responses through transduction of inhibitory signals. Recently, certain bacterial pathogens have been shown to suppress leukocyte innate immune responses by molecular mimicry of host sialic acid structures and engagement of inhibitory Siglecs. Our present work shows that the converse can be true, i.e., that a microbial sialic acid-cleaving enzyme can induce proinflammatory responses, which are in part mediated by unmasking of an inhibitory Siglec. We conclude that host leukocytes are poised to detect and respond to microbial sialidase activity with exaggerated inflammatory responses, which could be beneficial or detrimental to the host depending on the site, stage and magnitude of infection. Sialic acids decorate the surface of all mammalian cells and play important roles in physiology, development, and evolution. Siglecs are sialic acid-binding receptors on the surface of immune cells, many of which engage in cis interactions with host sialoglycan ligands and dampen inflammatory responses through transduction of inhibitory signals. Recently, certain bacterial pathogens have been shown to suppress leukocyte innate immune responses by molecular mimicry of host sialic acid structures and engagement of inhibitory Siglecs. Our present work shows that the converse can be true, i.e., that a microbial sialic acid-cleaving enzyme can induce proinflammatory responses, which are in part mediated by unmasking of an inhibitory Siglec. We conclude that host leukocytes are poised to detect and respond to microbial sialidase activity with exaggerated inflammatory responses, which could be beneficial or detrimental to the host depending on the site, stage and magnitude of infection.
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Development and characterization of protective Haemophilus parasuis subunit vaccines based on native proteins with affinity to porcine transferrin and comparison with other subunit and commercial vaccines. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2010; 18:50-8. [PMID: 20926701 DOI: 10.1128/cvi.00314-10] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Haemophilus parasuis is the agent responsible for causing Glässer's disease, which is characterized by fibrinous polyserositis, polyarthritis, and meningitis in pigs. In this study, we have characterized native outer membrane proteins with affinity to porcine transferrin (NPAPT) from H. parasuis serovar 5, Nagasaki strain. This pool of proteins was used as antigen to developed two vaccine formulations: one was adjuvanted with a mineral oil (Montanide IMS 2215 VG PR), while the other was potentiated with a bacterial neuraminidase from Clostridium perfringens. The potential protective effect conferred by these two vaccines was compared to that afforded by two other vaccines, consisting of recombinant transferrin-binding protein (rTbp) A or B fragments from H. parasuis, Nagasaki strain, and by a commercially available inactivated vaccine. Five groups of colostrum-deprived piglets immunized with the vaccines described above, one group per each vaccine, and a group of nonvaccinated control animals were challenged intratracheally with a lethal dose (3 × 10⁸ CFU) of H. parasuis, Nagasaki strain. The two vaccines containing rTbps yielded similar results with minimal protection against death, clinical signs, gross and microscopic lesions, and H. parasuis invasion. In contrast, the two vaccines composed of NPAPT antigen and commercial bacterin resulted in a strong protection against challenge (without deaths and clinical signs), mild histopathological changes, and no recovery of H. parasuis, thus suggesting their effectiveness in preventing Glässer's disease outbreaks caused by serovar 5.
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Stamatos NM, Carubelli I, van de Vlekkert D, Bonten EJ, Papini N, Feng C, Venerando B, d'Azzo A, Cross AS, Wang LX, Gomatos PJ. LPS-induced cytokine production in human dendritic cells is regulated by sialidase activity. J Leukoc Biol 2010; 88:1227-39. [PMID: 20826611 DOI: 10.1189/jlb.1209776] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Removal of sialic acid from glycoconjugates on the surface of monocytes enhances their response to bacterial LPS. We tested the hypothesis that endogenous sialidase activity creates a permissive state for LPS-induced cytokine production in human monocyte-derived DCs. Of the four genetically distinct sialidases (Neu1-4), Neu1, Neu3, and Neu4 are expressed in human monocytes, but only Neu1 and Neu3 are up-regulated as cells differentiate into DCs. Neu1 and Neu3 are present on the surface of monocytes and DCs and are also present intracellularly. DCs contain a greater amount of sialic acid than monocytes, but the amount of sialic acid/mg total protein declines during differentiation to DCs. This relative hyposialylation of cells does not occur in mature DCs grown in the presence of zanamivir, a pharmacologic inhibitor of Neu3 but not Neu1, or DANA, an inhibitor of Neu1 and Neu3. Inhibition of sialidase activity during differentiation to DCs causes no detectable change in cell viability or expression of DC surface markers. Differentiation of monocytes into DCs in the presence of zanamivir results in reduced LPS- induced expression of IL-6, IL-12p40, and TNF-α by mature DCs, demonstrating a role for Neu3 in cytokine production. A role for Neu3 is supported by inhibition of cytokine production by DANA in DCs from Neu1⁻/⁻ and WT mice. We conclude that sialidase-mediated change in sialic acid content of specific cell surface glycoconjugates in DCs regulates LPS-induced cytokine production, thereby contributing to development of adaptive immune responses.
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Affiliation(s)
- Nicholas M Stamatos
- University of Maryland Medical Center, 725 West Lombard St., Baltimore, MD 21201, USA.
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Monti E, Bonten; E, D'Azzo A, Bresciani R, Venerando B, Borsani G, Schauer R, Tettamanti G. Sialidases in Vertebrates. Adv Carbohydr Chem Biochem 2010; 64:403-79. [DOI: 10.1016/s0065-2318(10)64007-3] [Citation(s) in RCA: 135] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Bacterial neuraminidase increases IL-8 production in lung epithelial cells via NF-κB-dependent pathway. Biochem Biophys Res Commun 2009; 379:754-9. [DOI: 10.1016/j.bbrc.2008.12.120] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2008] [Accepted: 12/23/2008] [Indexed: 01/09/2023]
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33
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Curreli S, Arany Z, Gerardy-Schahn R, Mann D, Stamatos NM. Polysialylated Neuropilin-2 Is Expressed on the Surface of Human Dendritic Cells and Modulates Dendritic Cell-T Lymphocyte Interactions. J Biol Chem 2007; 282:30346-56. [PMID: 17699524 DOI: 10.1074/jbc.m702965200] [Citation(s) in RCA: 145] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Polysialic acid (PSA) is a unique linear homopolymer of alpha2,8-linked sialic acid that has been identified as a posttranslational modification on only five mammalian proteins. Studied predominantly on neural cell adhesion molecule (NCAM) during development of the vertebrate nervous system, PSA modulates cell interactions mediated by NCAM and other adhesion molecules. An isoform of NCAM (CD56) on natural killer (NK) cells is the only protein known to be polysialylated in cells of the immune system, yet the function of PSA in NK cells remains unclear. We show here that neuropilin-2 (NRP-2), a receptor for the semaphorin and vascular endothelial growth factor families in neurons and endothelial cells, respectively, is expressed on the surface of human dendritic cells and is polysialylated. Expression of NRP-2 is up-regulated during dendritic cell maturation, coincident with increased expression of ST8Sia IV, one of the key enzymes of PSA biosynthesis, and with the appearance of PSA on the cell surface. PSA on NRP-2 is resistant to digestion with peptide N-glycosidase F but is sensitive to release under alkaline conditions, suggesting that PSA chains are added to O-linked glycans of NRP-2. Removal of polysialic acid from the surface of dendritic cells or binding of NRP-2 with specific IgG promoted dendritic cell-induced activation and proliferation of T lymphocytes. Thus, this newly recognized polysialylated protein on the surface of dendritic cells influences dendritic cell-T lymphocyte interactions through one or more of its distinct extracellular domains.
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Affiliation(s)
- Sabrina Curreli
- Institute of Human Virology, University of Maryland, Baltimore, Maryland 21201, USA
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Takahata M, Iwasaki N, Nakagawa H, Abe Y, Watanabe T, Ito M, Majima T, Minami A. Sialylation of cell surface glycoconjugates is essential for osteoclastogenesis. Bone 2007; 41:77-86. [PMID: 17512814 DOI: 10.1016/j.bone.2007.03.016] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2007] [Revised: 03/17/2007] [Accepted: 03/20/2007] [Indexed: 10/23/2022]
Abstract
Sialic acid, which is located at the end of the carbohydrate moiety of cell surface glycoconjugates, is involved in many biologic responses, such as intercellular reactions and virus-cell fusion, especially in hematopoietic cells. Here we provide experimental evidence that the sialic acid of cell surface glycoconjugates has a role in osteoclast differentiation. Lectin histochemical study demonstrated the existence of both alpha (2,3)-linked-sialic acid and alpha (2,6)-linked-sialic acid in mouse bone marrow-derived macrophages and in the RAW264.7 macrophage cell line, which are osteoclast precursors. Flow cytometric analysis of surface lectin staining revealed the kinetics of these sialic acids during osteoclastogenesis: alpha (2,3)-linked-sialic acid was abundantly expressed throughout osteoclastogenesis, whereas alpha (2,6)-linked-sialic acid levels declined at the terminal stage of osteoclast differentiation. To investigate the role of sialic acid in osteoclast differentiation, we performed an osteoclastogenesis assay with or without exogenous sialidase treatment. Desialylated cells formed TRAP-positive mononuclear cells, but did not become multinuclear cells despite the normal expression of osteoclast markers such as cathepsin K, integrin beta3, and nuclear factor-ATc1. Flow cytometric analysis also demonstrated that exogenous sialidase effectively removed alpha (2,6)-linked-sialic acid, but only slightly changed the alpha (2,3)-linked-sialic acid content, suggesting that alpha (2,6)-linked-sialic acid might be involved in osteoclast differentiation. Findings from knockdown analysis using small interfering RNA oligonucleotides against alpha 2,6-sialyltransferase support this idea: alpha (2,6)-linked-sialic acid-deficient cells markedly inhibit the formation of multinuclear osteoclasts. Our findings suggest that alpha (2,6)-linked-sialic acid of cell surface glycoconjugates has a role in osteoclast differentiation, possibly via its role in the cell-cell fusion process.
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Affiliation(s)
- Masahiko Takahata
- Department of Orthopaedic Surgery, Hokkaido University Graduate School of Medicine, Kita-15 Nishi-7, Kita-ku, Sapporo 060-8638, Japan.
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Duca L, Blanchevoye C, Cantarelli B, Ghoneim C, Dedieu S, Delacoux F, Hornebeck W, Hinek A, Martiny L, Debelle L. The elastin receptor complex transduces signals through the catalytic activity of its Neu-1 subunit. J Biol Chem 2007; 282:12484-91. [PMID: 17327233 DOI: 10.1074/jbc.m609505200] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The binding of elastin peptides on the elastin receptor complex leads to the formation of intracellular signals but how this is achieved remains totally unknown. Using pharmacological inhibitors of the enzymatic activities of its subunits, we show here that the elastin peptide-driven ERK1/2 activation and subsequent pro-MMP-1 production, observed in skin fibroblasts when they are cultured in the presence of these peptides, rely on a membrane-bound sialidase activity. As lactose blocked this effect, the elastin receptor sialidase subunit, Neu-1, seemed to be involved. The use of a catalytically inactive form of Neu-1 and the small interfering RNA-mediated decrease of Neu-1 expression strongly support this view. Finally, we report that N-acetyl neuraminic acid can reproduce the effects of elastin peptides on both ERK1/2 activation and pro-MMP-1 production. Altogether, our results indicate that the enzymatic activity of the Neu-1 subunit of the elastin receptor complex is responsible for its signal transduction, presumably through sialic acid generation from undetermined substrates.
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Affiliation(s)
- Laurent Duca
- Laboratoire de Biochimie, UMR CNRS 6198, Faculté des Sciences, Moulin de la Housse, BP 1039, 51687 Reims Cedex 2, France
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Nan X, Carubelli I, Stamatos NM. Sialidase expression in activated human T lymphocytes influences production of IFN-gamma. J Leukoc Biol 2006; 81:284-96. [PMID: 17028199 DOI: 10.1189/jlb.1105692] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Sialidases influence cellular activity by removing terminal sialic acid from glycoproteins and glycolipids. Four genetically distinct sialidases (Neu1-4) have been identified in mammalian cells. In this study, we demonstrate that only lysosomal Neu1 and plasma membrane-associated Neu3 are detected in freshly isolated and activated human T lymphocytes. Activation of lymphocytes by exposure to anti-CD3 and anti-CD28 IgG resulted in a ninefold increase in Neu1-specific activity after growth of cells in culture for 5 days. In contrast, the activity of Neu3 changed minimally in activated lymphocytes. The increase in Neu1 enzyme activity correlated with increased synthesis of Neu1-specific mRNA. Neu1 was present on the surface of freshly isolated and activated CD4 and CD8 T lymphocytes, as determined by staining intact cells with anti-Neu1 IgG and analysis by flow cytometry and by Western blot analysis of biotin-labeled cell surface proteins. Cell surface Neu1 was found tightly associated with a subunit of protective protein/cathepsin A (PPCA). Compared with freshly isolated lymphocytes, activated cells expressed more surface binding sites for galactose-recognizing lectins Erythrina cristagalli (ECA) and Arachis hypogaea. Growth of cells in the presence of sialidase inhibitors 2,3-dehydro-2-deoxy-N-acetylneuraminic acid or 4-guanidino-2-deoxy-2,3-dehydro-N-acetylneuraminic acid resulted in a smaller increase in number of ECA-binding sites and a greater amount of cell surface sialic acid in activated cells. Inhibition of sialidase activity also resulted in reduced expression of IFN-gamma in activated cells. The down-regulation of IFN-gamma occurred at the transcriptional level. Thus, sialidase activity in activated T lymphocytes contributes to the hyposialylation of specific cell surface glycoconjugates and to the production of IFN-gamma.
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Affiliation(s)
- Xinli Nan
- Institute of Human Biology, and Department of Medicine, University of Maryland Medical Center, 725 West Lombard Street, Baltimore, MD 21201, USA
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Stamatos NM, Liang F, Nan X, Landry K, Cross AS, Wang LX, Pshezhetsky AV. Differential expression of endogenous sialidases of human monocytes during cellular differentiation into macrophages. FEBS J 2005; 272:2545-56. [PMID: 15885103 DOI: 10.1111/j.1742-4658.2005.04679.x] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Sialidases are enzymes that influence cellular activity by removing terminal sialic acid from glycolipids and glycoproteins. Four genetically distinct sialidases have been identified in mammalian cells. In this study, we demonstrate that three of these sialidases, lysosomal Neu1 and Neu4 and plasma membrane-associated Neu3, are expressed in human monocytes. When measured using the artificial substrate 2'-(4-methylumbelliferyl)-alpha-d-N-acetylneuraminic acid (4-MU-NANA), sialidase activity of monocytes increased up to 14-fold per milligram of total protein after cells had differentiated into macrophages. In these same cells, the specific activity of other cellular proteins (e.g. beta-galactosidase, cathepsin A and alkaline phosphatase) increased only two- to fourfold during differentiation of monocytes. Sialidase activity measured with 4-MU-NANA resulted from increased expression of Neu1, as removal of Neu1 from the cell lysate by immunoprecipitation eliminated more than 99% of detectable sialidase activity. When exogenous mixed bovine gangliosides were used as substrates, there was a twofold increase in sialidase activity per milligram of total protein in monocyte-derived macrophages in comparison to monocytes. The increased activity measured with mixed gangliosides was not affected by removal of Neu1, suggesting that the expression of a sialidase other than Neu1 was present in macrophages. The amount of Neu1 and Neu3 RNAs detected by real time RT-PCR increased as monocytes differentiated into macrophages, whereas the amount of Neu4 RNA decreased. No RNA encoding the cytosolic sialidase (Neu2) was detected in monocytes or macrophages. Western blot analysis using specific antibodies showed that the amount of Neu1 and Neu3 proteins increased during monocyte differentiation. Thus, the differentiation of monocytes into macrophages is associated with regulation of the expression of at least three distinct cellular sialidases, with specific up-regulation of the enzyme activity of only Neu1.
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Affiliation(s)
- Nicholas M Stamatos
- Institute of Human Virology, University of Maryland, Baltimore, MD 21201, USA.
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Wen YJ, Mancino A, Pashov A, Whitehead T, Stanley J, Kieber-Emmons T. Antigen binding of human IgG Fabs mediate ERK-associated proliferation of human breast cancer cells. DNA Cell Biol 2005; 24:73-84. [PMID: 15699628 DOI: 10.1089/dna.2005.24.73] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Serum-circulating antibody can be linked to poor outcomes in some cancer patients. To investigate the role of human antibodies in regulating tumor cell growth, we constructed a recombinant cDNA expression library of human IgG Fab from a patient with breast cancer. Clones were screened from the library with breast tumor cell lysate. Sequence analysis of the clones showed somatic hypermutations when compared to their closest VH/VL germ-line genes. Initial characterizations focused on five clones. All tested clones displayed stronger binding to antigen derived from primary breast cancers and established breast cancer cell lines than to normal breast tissues. In vitro functional studies showed that four out of five tested clones could stimulate the growth of MDA-MB-231 breast cancer cell lines, and one out of five was able to promote MCF-7 cell growth as well. Involvement of ERK2 pathway was observed. By 1H-NMR spectra and Western blot analysis, it was evident that two tested antibody Fabs are capable of interacting with sialic acid. Our study suggests a possible role for human antibody in promoting tumor cell growth by direct binding of IgG Fab to breast tumor antigen. Such studies prompt speculation regarding the role of serum antibodies in mediating tumor growth as well as their contribution to disease progression.
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Affiliation(s)
- Yue-Jin Wen
- Department of Pathology, Arkansas Cancer Research Center, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205, USA
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