51
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Nanoparticles Equipped with α2,8-Linked Sialic Acid Chains Inhibit the Release of Neutrophil Extracellular Traps. NANOMATERIALS 2019; 9:nano9040610. [PMID: 31013834 PMCID: PMC6523985 DOI: 10.3390/nano9040610] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Revised: 03/18/2019] [Accepted: 04/02/2019] [Indexed: 11/16/2022]
Abstract
Neutrophils can combat the invasion of pathogens by the formation of neutrophil extracellular traps (NETs). The NET mechanism is not only an effective tool for combating pathogens, but is also associated with diseases. Therefore, NETs are a potential target for combating pathologies, such as cystic fibrosis and thrombosis. We investigated the potential of nanoparticles, which were modified with α2,8-linked sialic acid chains, to modulate NET release during phorbol myristate acetate stimulation. Interestingly, when these nanoparticles were applied, the formation of reactive oxygen species was partly inhibited and the release of NET was counteracted. However, although the release of NET fibers was prevented, the nuclei still lost their characteristic segmented structure and became swollen, indicating that only the release, and not complete activation was suppressed. Intriguingly, coincubation of α2,8-sialylated particles with free sialic acid chains prevented the outlined inhibitory effects. Thus, the sialic acid chains must be attached to a linker molecule to generate an active bioconjugate that is able to inhibit the release of NET.
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52
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Sialic acid as a target for the development of novel antiangiogenic strategies. Future Med Chem 2018; 10:2835-2854. [PMID: 30539670 DOI: 10.4155/fmc-2018-0298] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Sialic acid is associated with glycoproteins and gangliosides of eukaryotic cells. It regulates various molecular interactions, being implicated in inflammation and cancer, where its expression is regulated by sialyltransferases and sialidases. Angiogenesis, the formation of new capillaries, takes place during inflammation and cancer, and represents the outcome of several interactions occurring at the endothelial surface among angiogenic growth factors, inhibitors, receptors, gangliosides and cell-adhesion molecules. Here, we elaborate on the evidences that many structures involved in angiogenesis are sialylated and that their interactions depend on sialic acid with implications in angiogenesis itself, inflammation and cancer. We also discuss the possibility to exploit sialic acid as a target for the development of novel antiangiogenic drugs.
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53
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Choi HJ, Chung TW, Choi HJ, Han JH, Choi JH, Kim CH, Ha KT. Increased α2-6 sialylation of endometrial cells contributes to the development of endometriosis. Exp Mol Med 2018; 50:1-12. [PMID: 30542051 PMCID: PMC6290765 DOI: 10.1038/s12276-018-0167-1] [Citation(s) in RCA: 77] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Revised: 05/30/2018] [Accepted: 06/12/2018] [Indexed: 12/18/2022] Open
Abstract
Endometriosis is a disease characterized by implants of endometrial tissue outside the uterine cavity and is strongly associated with infertility. Focal adhesion of endometrial tissue to the peritoneum is an indication of incipient endometriosis. In this study, we examined the effect of various cytokines that are known to be involved in the pathology of endometriosis on endometrial cell adhesion. Among the investigated cytokines, transforming growth factor-β1 (TGF-β1) increased adhesion of endometrial cells to the mesothelium through induction of α2-6 sialylation. The expression levels of β-galactoside α2-6 sialyltransferase (ST6Gal) 1 and ST6Gal2 were increased through activation of TGF-βRI/SMAD2/3 signaling in endometrial cells. In addition, we discovered that terminal sialic acid glycan epitopes of endometrial cells engage with sialic acid-binding immunoglobulin-like lectin-9 expressed on mesothelial cell surfaces. Interestingly, in an in vivo mouse endometriosis model, inhibition of endogenous sialic acid binding by a NeuAcα2-6Galβ1-4GlcNAc injection diminished TGF-β1-induced formation of endometriosis lesions. Based on these results, we suggest that increased sialylation of endometrial cells by TGF-β1 promotes the attachment of endometrium to the peritoneum, encouraging endometriosis outbreaks. A growth factor involved in cell differentiation and proliferation contributes to the development of endometriosis by stimulating a protein modification mechanism that increases the adhesiveness of cells lining the uterus. Endometriosis results when these cells, known as endometrial cells, start growing outside the uterus causing pelvic pain, heavy periods and, in some cases, infertility. Ki-Tae Ha at Pusan National University, Yangsan, South Korea, and colleagues found that transforming growth factor-β1 signaling promoted the addition of sialic acid sugar units onto endometrial cell surface proteins. This modification enhanced the adhesion of endometrial cells to mesothelial cells, which line other internal organs, and the formation of endometriosis lesions in mice. Preventing sialic acid binding to its mesothelial cell receptor reduced lesion formation. The findings reveal a new molecular mechanism underlying endometriosis and a potential treatment strategy.
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Affiliation(s)
- Hee-Jin Choi
- Department of Korean Medical Science, School of Korean Medicine, Seoul, Republic of Korea.,Healthy Aging Korean Medical Research Center, Pusan National University, Yangsan, Gyeongnam, 50612, Republic of Korea.,Graduate Training Program of Korean Medicine for Healthy-aging, Pusan National University, Yangsan, Gyeongnam, 50612, Republic of Korea
| | - Tae-Wook Chung
- Healthy Aging Korean Medical Research Center, Pusan National University, Yangsan, Gyeongnam, 50612, Republic of Korea
| | - Hee-Jung Choi
- Healthy Aging Korean Medical Research Center, Pusan National University, Yangsan, Gyeongnam, 50612, Republic of Korea
| | - Jung Ho Han
- Department of Korean Medical Science, School of Korean Medicine, Seoul, Republic of Korea.,Healthy Aging Korean Medical Research Center, Pusan National University, Yangsan, Gyeongnam, 50612, Republic of Korea.,Graduate Training Program of Korean Medicine for Healthy-aging, Pusan National University, Yangsan, Gyeongnam, 50612, Republic of Korea
| | - Jung-Hye Choi
- Department of Life and Nanopharmaceutical Sciences and Department of Oriental Pharmacy, Kyung Hee University, Seoul, 02447, Republic of Korea
| | - Cheorl-Ho Kim
- Department of Biological Science, Sungkyunkwan University, Suwon, Kyunggi-do, 16419, Republic of Korea
| | - Ki-Tae Ha
- Department of Korean Medical Science, School of Korean Medicine, Seoul, Republic of Korea. .,Healthy Aging Korean Medical Research Center, Pusan National University, Yangsan, Gyeongnam, 50612, Republic of Korea. .,Graduate Training Program of Korean Medicine for Healthy-aging, Pusan National University, Yangsan, Gyeongnam, 50612, Republic of Korea.
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54
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Bornhöfft KF, Goldammer T, Rebl A, Galuska SP. Siglecs: A journey through the evolution of sialic acid-binding immunoglobulin-type lectins. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2018; 86:219-231. [PMID: 29751010 DOI: 10.1016/j.dci.2018.05.008] [Citation(s) in RCA: 95] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 05/04/2018] [Accepted: 05/04/2018] [Indexed: 05/11/2023]
Abstract
Siglecs (sialic acid-binding immunoglobulin-type lectins) are a family of immune regulatory receptors predominantly found on the cells of the hematopoietic system. A V-set Ig-like domain mediates the recognition of different sialylated glycoconjugates, which can lead to the activation or inhibition of the immune response, depending on the involved Siglecs. Siglecs are categorized into two subgroups: one including all CD33-related Siglecs and the other consisting of Siglec-1 (Sialoadhesin), Siglec-2 (CD22), Siglec-4 (myelin-associated glycoprotein, MAG) and Siglec-15. In contrast to the members of the CD33-related Siglecs, which share ∼50-99% sequence identity, Siglecs of the other subgroup show quite low homology (approximately 25-30% sequence identity). Based on the published sequences and functions of Siglecs, we performed phylogenetic analyses and sequence alignments to reveal the conservation of Siglecs throughout evolution. Therefore, we focused on the presence of Siglecs in different classes of vertebrates (fishes, amphibians, birds, reptiles and mammals), offering a bridge between the presence of different Siglecs and the biological situations of the selected animals.
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Affiliation(s)
- Kim F Bornhöfft
- Institute of Reproductive Biology, Leibniz Institute for Farm Animal Biology (FBN), Wilhelm-Stahl-Allee 2, 18196 Dummerstorf, Germany
| | - Tom Goldammer
- Institute of Genome Biology, Leibniz Institute for Farm Animal Biology (FBN), Wilhelm-Stahl-Allee 2, 18196 Dummerstorf, Germany
| | - Alexander Rebl
- Institute of Genome Biology, Leibniz Institute for Farm Animal Biology (FBN), Wilhelm-Stahl-Allee 2, 18196 Dummerstorf, Germany.
| | - Sebastian P Galuska
- Institute of Reproductive Biology, Leibniz Institute for Farm Animal Biology (FBN), Wilhelm-Stahl-Allee 2, 18196 Dummerstorf, Germany.
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55
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Chang J, Peng H, Shaffer BC, Baskar S, Wecken IC, Cyr MG, Martinez GJ, Soden J, Freeth J, Wiestner A, Rader C. Siglec-6 on Chronic Lymphocytic Leukemia Cells Is a Target for Post-Allogeneic Hematopoietic Stem Cell Transplantation Antibodies. Cancer Immunol Res 2018; 6:1008-1013. [PMID: 29980538 DOI: 10.1158/2326-6066.cir-18-0102] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Revised: 04/27/2018] [Accepted: 06/28/2018] [Indexed: 11/16/2022]
Abstract
Although the 5-year survival rate of chronic lymphocytic leukemia (CLL) patients has risen to >80%, the only potentially curative treatment is allogeneic hematopoietic stem cell transplantation (alloHSCT). To identify possible new monoclonal antibody (mAb) drugs and targets for CLL, we previously developed a phage display-based human mAb platform to mine the antibody repertoire of patients who responded to alloHSCT. We had selected a group of highly homologous post-alloHSCT mAbs that bound to an unknown CLL cell surface antigen. Here, we show through next-generation sequencing of cDNAs encoding variable heavy-chain domains that these mAbs had a relative abundance of ∼0.1% in the post-alloHSCT antibody repertoire and were enriched ∼1,000-fold after three rounds of selection on primary CLL cells. Based on differential RNA-seq and a cell microarray screening technology for discovering human cell surface antigens, we now identify their antigen as Siglec-6. We verified this finding by flow cytometry, ELISA, siRNA knockdown, and surface plasmon resonance. Siglec-6 was broadly expressed in CLL and could be a potential target for antibody-based therapeutic interventions. Our study reaffirms the utility of post-alloHSCT antibody drug and target discovery. Cancer Immunol Res; 6(9); 1008-13. ©2018 AACR.
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Affiliation(s)
- Jing Chang
- Department of Immunology and Microbiology, The Scripps Research Institute, Jupiter, Florida
| | - Haiyong Peng
- Department of Immunology and Microbiology, The Scripps Research Institute, Jupiter, Florida
| | - Brian C Shaffer
- Experimental Transplantation and Immunology Branch, Center for Cancer Research, NCI, NIH, Bethesda, Maryland
| | - Sivasubramanian Baskar
- Experimental Transplantation and Immunology Branch, Center for Cancer Research, NCI, NIH, Bethesda, Maryland
| | - Ina C Wecken
- Department of Immunology and Microbiology, The Scripps Research Institute, Jupiter, Florida
| | - Matthew G Cyr
- Department of Immunology and Microbiology, The Scripps Research Institute, Jupiter, Florida
| | | | - Jo Soden
- Retrogenix Ltd, High Peak, United Kingdom
| | - Jim Freeth
- Retrogenix Ltd, High Peak, United Kingdom
| | - Adrian Wiestner
- Hematology Branch, National Heart, Lung, and Blood Institute, NIH, Bethesda, Maryland
| | - Christoph Rader
- Department of Immunology and Microbiology, The Scripps Research Institute, Jupiter, Florida. .,Experimental Transplantation and Immunology Branch, Center for Cancer Research, NCI, NIH, Bethesda, Maryland
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56
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Sioud M, Westby P, Vasovic V, Fløisand Y, Peng Q. Development of a new high-affinity human antibody with antitumor activity against solid and blood malignancies. FASEB J 2018; 32:5063-5077. [PMID: 29913558 DOI: 10.1096/fj.201701544r] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
mAbs have emerged as a promising strategy for the treatment of cancer. However, in several malignancies, no effective antitumor mAbs are yet available. Identifying therapeutic mAbs that recognize common tumor antigens could render the treatment widely applicable. Here, a human single-chain variable fragment (scFv) antibody library was sequentially affinity selected against a panel of human cancer cell lines and an antibody fragment (named MS5) that bound to solid and blood cancer cells was identified. The MS5 scFv was fused to the human IgG1 Fc domain to generate an antibody (MS5-Fc fusion) that induced antibody-dependent cellular cytotoxicity and phagocytosis of cancer cells by macrophages. In addition, the MS5-Fc antibody bound to primary leukemia cells and induced antibody-dependent cellular cytotoxicity. In the majority of analyzed cancer cells, the MS5-Fc antibody induced cell surface redistribution of the receptor complexes, but not internalization, thus maximizing the accessibility of the IgG1 Fc domain to immune effector cells. In vitro stability studies showed that the MS5-Fc antibody was stable after 6 d of incubation in human serum, retaining ∼60% of its initial intact form. After intravenous injections, the antibody localized into tumor tissues and inhibited the growth of 3 different human tumor xenografts (breast, lymphoma, and leukemia). These antitumor effects were associated with tumor infiltration by macrophages and NK cells. In the Ramos B-cell lymphoma xenograft model, the MS5-Fc antibody exhibited a comparable antitumor effect as rituximab, a chimeric anti-CD20 IgG1 mAb. These results indicate that human antibodies with pan-cancer abilities can be generated from phage display libraries, and that the engineered MS5-Fc antibody could be an attractive agent for further clinical investigation.-Sioud, M., Westby, P., Vasovic, V., Fløisand, Y., Peng, Q. Development of a new high-affinity human antibody with antitumor activity against solid and blood malignancies.
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Affiliation(s)
- Mouldy Sioud
- Department of Cancer Immunology, Rikshospitalet-Radiumhospitalet, University Hospital, Oslo, Norway
| | - Phuong Westby
- Department of Cancer Immunology, Rikshospitalet-Radiumhospitalet, University Hospital, Oslo, Norway
| | - Vlada Vasovic
- Department of Pathology, Rikshospitalet-Radiumhospitalet, University Hospital, Oslo, Norway; and
| | - Yngvar Fløisand
- Department of Hematology, Rikshospitalet-Radiumhospitalet, University Hospital, Oslo, Norway
| | - Qian Peng
- Department of Pathology, Rikshospitalet-Radiumhospitalet, University Hospital, Oslo, Norway; and
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57
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Triantis V, Bode L, van Neerven RJJ. Immunological Effects of Human Milk Oligosaccharides. Front Pediatr 2018; 6:190. [PMID: 30013961 PMCID: PMC6036705 DOI: 10.3389/fped.2018.00190] [Citation(s) in RCA: 184] [Impact Index Per Article: 30.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 06/08/2018] [Indexed: 12/15/2022] Open
Abstract
Human milk oligosaccharides (HMOs) comprise a group of structurally complex, unconjugated glycans that are highly abundant in human milk. HMOs are minimally digested in the gastrointestinal tract and reach the colon intact, where they shape the microbiota. A small fraction of HMOs is absorbed, reaches the systemic circulation, and is excreted in urine. HMOs can bind to cell surface receptors expressed on epithelial cells and cells of the immune system and thus modulate neonatal immunity in the infant gut, and possibly also sites throughout the body. In addition, they have been shown to act as soluble decoy receptors to block the attachment of various microbial pathogens to cells. This review summarizes the current knowledge of the effects HMOs can have on infections, allergies, auto-immune diseases and inflammation, and will focus on the role of HMOs in altering immune responses through binding to immune-related receptors.
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Affiliation(s)
| | - Lars Bode
- Department of Pediatrics, University of California, San Diego, San Diego, CA, United States
| | - R J Joost van Neerven
- FrieslandCampina, Amersfoort, Netherlands.,Wageningen University and Research, Cell Biology and Immunology, Wageningen, Netherlands
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58
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Menicucci AR, Versteeg K, Woolsey C, Mire CE, Geisbert JB, Cross RW, Agans KN, Jankeel A, Geisbert TW, Messaoudi I. Transcriptome Analysis of Circulating Immune Cell Subsets Highlight the Role of Monocytes in Zaire Ebola Virus Makona Pathogenesis. Front Immunol 2017; 8:1372. [PMID: 29123522 PMCID: PMC5662559 DOI: 10.3389/fimmu.2017.01372] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2017] [Accepted: 10/05/2017] [Indexed: 12/27/2022] Open
Abstract
Existing models of Ebola virus disease (EVD) suggest antigen-presenting cells are initial targets of Zaire ebolavirus (ZEBOV). In vitro studies have shown that ZEBOV infection of monocytes and macrophages results in the production of inflammatory mediators, which may cause lymphocyte apoptosis. However, these findings have not been corroborated by in vivo studies. In this study, we report the first longitudinal analysis of transcriptional changes in purified monocytes, T-cells, and B-cells isolated from cynomolgus macaques following infection with ZEBOV-Makona. Our data reveal monocytes as one of the major immune cell subsets that supports ZEBOV replication in vivo. In addition, we report a marked increase in the transcription of genes involved in inflammation, coagulation, and vascular disease within monocytes, suggesting that monocytes contribute to EVD manifestations. Further, genes important for antigen presentation and regulation of immunity were downregulated, potentially subverting development of adaptive immunity. In contrast, lymphocytes, which do not support ZEBOV replication, showed transcriptional changes limited to a small number of interferon-stimulated genes (ISGs) and a failure to upregulate genes associated with an antiviral effector immune response. Collectively, these data suggest that ZEBOV-infected monocytes play a significant role in ZEBOV-Makona pathogenesis and strategies to suppress virus replication or modify innate responses to infection in these cells should be a priority for therapeutic intervention.
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Affiliation(s)
- Andrea R Menicucci
- Division of Biomedical Sciences, University of California, Riverside, Riverside, CA, United States
| | - Krista Versteeg
- Galveston National Laboratory, Galveston, TX, United States.,Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, United States
| | - Courtney Woolsey
- Galveston National Laboratory, Galveston, TX, United States.,Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, United States
| | - Chad E Mire
- Galveston National Laboratory, Galveston, TX, United States.,Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, United States
| | - Joan B Geisbert
- Galveston National Laboratory, Galveston, TX, United States.,Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, United States
| | - Robert W Cross
- Galveston National Laboratory, Galveston, TX, United States.,Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, United States
| | - Krystle N Agans
- Galveston National Laboratory, Galveston, TX, United States.,Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, United States
| | - Allen Jankeel
- Department of Molecular Biology and Biochemistry, College of Biological Sciences, University of California, Irvine, Irvine, CA, United States
| | - Thomas W Geisbert
- Galveston National Laboratory, Galveston, TX, United States.,Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, United States
| | - Ilhem Messaoudi
- Department of Molecular Biology and Biochemistry, College of Biological Sciences, University of California, Irvine, Irvine, CA, United States
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59
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Peng W, Paulson JC. CD22 Ligands on a Natural N-Glycan Scaffold Efficiently Deliver Toxins to B-Lymphoma Cells. J Am Chem Soc 2017; 139:12450-12458. [PMID: 28829594 DOI: 10.1021/jacs.7b03208] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
CD22 is a sialic acid-binding immunoglobulin-like lectin (Siglec) that is highly expressed on B-cells and B cell lymphomas, and is a validated target for antibody and nanoparticle based therapeutics. However, cell targeted therapeutics are limited by their complexity, heterogeneity, and difficulties in production. We describe here a chemically defined natural N-linked glycan scaffold that displays high affinity CD22 glycan ligands and outcompetes the natural ligand for the receptor, resulting in single molecule binding to CD22 and endocytosis into cells. Binding affinity is increased by up to 1500-fold compared to the monovalent ligand, while maintaining the selectivity for hCD22 over other Siglecs. Conjugates of these multivalent ligands with auristatin and saporin toxins are efficiently internalized via hCD22 resulting in killing of B-cell lymphoma cells. This single molecule ligand targeting strategy represents an alternative to antibody- and nanoparticle-mediated approaches for delivery of agents to cells expressing CD22 and other Siglecs.
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Affiliation(s)
- Wenjie Peng
- Departments of Molecular Medicine and Immunology & Microbiology, The Scripps Research Institute , 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - James C Paulson
- Departments of Molecular Medicine and Immunology & Microbiology, The Scripps Research Institute , 10550 North Torrey Pines Road, La Jolla, California 92037, United States
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60
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Erythrocyte sialoglycoproteins engage Siglec-9 on neutrophils to suppress activation. Blood 2017; 129:3100-3110. [PMID: 28416510 DOI: 10.1182/blood-2016-11-751636] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Accepted: 04/04/2017] [Indexed: 12/13/2022] Open
Abstract
Healthy blood neutrophils are functionally quiescent in the bloodstream, have a short lifespan, and exit the circulation to carry out innate immune functions, or undergo rapid apoptosis and macrophage-mediated clearance to mitigate host tissue damage. Limitation of unnecessary intravascular neutrophil activation is also important to prevent serious inflammatory pathologies. Because neutrophils become easily activated after purification, we carried out ex vivo comparisons with neutrophils maintained in whole blood. We found a difference in activation state, with purified neutrophils showing signs of increased reactivity: shedding of l-selectin, CD11b upregulation, increased oxidative burst, and faster progression to apoptosis. We discovered that erythrocytes suppressed neutrophil activation ex vivo and in vitro, including reduced l-selectin shedding, oxidative burst, chemotaxis, neutrophil extracellular trap formation, bacterial killing, and induction of apoptosis. Selective and specific modification of sialic acid side chains on erythrocyte surfaces with mild sodium metaperiodate oxidation followed by aldehyde quenching with 4-methyl-3-thiosemicarbazide reduced neutrophil binding to erythrocytes and restored neutrophil activation. By enzyme-linked immunosorbent assay and immunofluorescence, we found that glycophorin A, the most abundant sialoglycoprotein on erythrocytes, engaged neutrophil Siglec-9, a sialic acid-recognizing receptor known to dampen innate immune cell activation. These studies demonstrate a previously unsuspected role for erythrocytes in suppressing neutrophils ex vivo and in vitro and help explain why neutrophils become easily activated after separation from whole blood. We propose that a sialic acid-based "self-associated molecular pattern" on erythrocytes also helps maintain neutrophil quiescence in the bloodstream. Our findings may be relevant to some prior experimental and clinical studies of neutrophils.
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61
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Mikulak J, Di Vito C, Zaghi E, Mavilio D. Host Immune Responses in HIV-1 Infection: The Emerging Pathogenic Role of Siglecs and Their Clinical Correlates. Front Immunol 2017; 8:314. [PMID: 28386256 PMCID: PMC5362603 DOI: 10.3389/fimmu.2017.00314] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Accepted: 03/06/2017] [Indexed: 11/25/2022] Open
Abstract
A better understanding of the mechanisms employed by HIV-1 to escape immune responses still represents one of the major tasks required for the development of novel therapeutic approaches targeting a disease still lacking a definitive cure. Host innate immune responses against HIV-1 are key in the early phases of the infection as they could prevent the development and the establishment of two hallmarks of the infection: chronic inflammation and viral reservoirs. Sialic acid-binding immunoglobulin-like lectins (Siglecs) belong to a family of transmembrane proteins able to dampen host immune responses and set appropriate immune activation thresholds upon ligation with their natural ligands, the sialylated carbohydrates. This immune-modulatory function is also targeted by many pathogens that have evolved to express sialic acids on their surface in order to escape host immune responses. HIV-1 envelope glycoprotein 120 (gp120) is extensively covered by carbohydrates playing active roles in life cycle of the virus. Indeed, besides forming a protecting shield from antibody recognition, this coat of N-linked glycans interferes with the folding of viral glycoproteins and enhances virus infectivity. In particular, the sialic acid residues present on gp120 can bind Siglec-7 on natural killer and monocytes/macrophages and Siglec-1 on monocytes/macrophages and dendritic cells. The interactions between these two members of the Siglec family and the sialylated glycans present on HIV-1 envelope either induce or increase HIV-1 entry in conventional and unconventional target cells, thus contributing to viral dissemination and disease progression. In this review, we address the impact of Siglecs in the pathogenesis of HIV-1 infection and discuss how they could be employed as clinic and therapeutic targets.
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Affiliation(s)
- Joanna Mikulak
- Unit of Clinical and Experimental Immunology, Humanitas Clinical and Research Center, Rozzano, Italy; Istituto di Ricerca Genetica e Biomedica, UOS di Milano, Consiglio Nazionale delle Ricerche (UOS/IRGB/CNR), Rozzano, Italy
| | - Clara Di Vito
- Unit of Clinical and Experimental Immunology, Humanitas Clinical and Research Center , Rozzano , Italy
| | - Elisa Zaghi
- Unit of Clinical and Experimental Immunology, Humanitas Clinical and Research Center , Rozzano , Italy
| | - Domenico Mavilio
- Unit of Clinical and Experimental Immunology, Humanitas Clinical and Research Center, Rozzano, Italy; Department of Medical Biotechnologies and Translational Medicine (BioMeTra), University of Milan, Milan, Italy
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62
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Bhide GP, Colley KJ. Sialylation of N-glycans: mechanism, cellular compartmentalization and function. Histochem Cell Biol 2017; 147:149-174. [PMID: 27975143 PMCID: PMC7088086 DOI: 10.1007/s00418-016-1520-x] [Citation(s) in RCA: 164] [Impact Index Per Article: 23.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/23/2016] [Indexed: 12/18/2022]
Abstract
Sialylated N-glycans play essential roles in the immune system, pathogen recognition and cancer. This review approaches the sialylation of N-glycans from three perspectives. The first section focuses on the sialyltransferases that add sialic acid to N-glycans. Included in the discussion is a description of these enzymes' glycan acceptors, conserved domain organization and sequences, molecular structure and catalytic mechanism. In addition, we discuss the protein interactions underlying the polysialylation of a select group of adhesion and signaling molecules. In the second section, the biosynthesis of sialic acid, CMP-sialic acid and sialylated N-glycans is discussed, with a special emphasis on the compartmentalization of these processes in the mammalian cell. The sequences and mechanisms maintaining the sialyltransferases and other glycosylation enzymes in the Golgi are also reviewed. In the final section, we have chosen to discuss processes in which sialylated glycans, both N- and O-linked, play a role. The first part of this section focuses on sialic acid-binding proteins including viral hemagglutinins, Siglecs and selectins. In the second half of this section, we comment on the role of sialylated N-glycans in cancer, including the roles of β1-integrin and Fas receptor N-glycan sialylation in cancer cell survival and drug resistance, and the role of these sialylated proteins and polysialic acid in cancer metastasis.
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Affiliation(s)
- Gaurang P Bhide
- Department of Biochemistry and Molecular Genetics, College of Medicine, The University of Illinois at Chicago, 900 S. Ashland Avenue, MC669, Chicago, IL, 60607, USA
| | - Karen J Colley
- Department of Biochemistry and Molecular Genetics, College of Medicine, The University of Illinois at Chicago, 900 S. Ashland Avenue, MC669, Chicago, IL, 60607, USA.
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63
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Ohira S, Yasuda Y, Tomita I, Kitajima K, Takahashi T, Sato C, Tanaka H. Synthesis of end-functionalized glycopolymers containing α(2,8) disialic acids via π-allyl nickel catalyzed coordinating polymerization and their interaction with Siglec-7. Chem Commun (Camb) 2017; 53:553-556. [DOI: 10.1039/c6cc07115e] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The polymerization of an allene glycomonomer efficiently provided glycopolymer possessing α(2,8) disialic acids with narrow PDI.
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Affiliation(s)
- Shuichi Ohira
- Department of Chemical Science and Engineering Tokyo Institute of Technology 2-12-1-H-101 Ookayama
- Tokyo 152-8552
- Japan
| | - Yu Yasuda
- Bioscience and Biotechnology Center
- Nagoya University Chikusa
- Nagoya 464-8601
- Japan
| | - Ikuyoshi Tomita
- Department of Chemical Science and Engineering Tokyo Institute of Technology 4259-G1-9
- Nagatsuta-cho
- Yokohama 226-8502
- Japan
| | - Ken Kitajima
- Bioscience and Biotechnology Center
- Nagoya University Chikusa
- Nagoya 464-8601
- Japan
| | | | - Chihiro Sato
- Bioscience and Biotechnology Center
- Nagoya University Chikusa
- Nagoya 464-8601
- Japan
| | - Hiroshi Tanaka
- Department of Chemical Science and Engineering Tokyo Institute of Technology 2-12-1-H-101 Ookayama
- Tokyo 152-8552
- Japan
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Bayón C, He N, Deir-Kaspar M, Blasco P, André S, Gabius HJ, Rumbero Á, Jiménez-Barbero J, Fessner WD, Hernáiz MJ. Direct Enzymatic Branch-End Extension of Glycocluster-Presented Glycans: An Effective Strategy for Programming Glycan Bioactivity. Chemistry 2016; 23:1623-1633. [DOI: 10.1002/chem.201604550] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Indexed: 12/12/2022]
Affiliation(s)
- Carlos Bayón
- Department of Organic and Pharmaceutical Chemistry; Faculty of Pharmacy; Complutense University; Plaza Ramón y CajaL s/n 28040 Madrid Spain
| | - Ning He
- Department of Organic Chemistry and Biochemistry; Technische Universität Darmstadt, A; larich-Weiss-Strasse 4 64287 Darmstadt Germany
| | - Mario Deir-Kaspar
- Department of Organic and Pharmaceutical Chemistry; Faculty of Pharmacy; Complutense University; Plaza Ramón y CajaL s/n 28040 Madrid Spain
| | - Pilar Blasco
- Departamento de Ciencia de Proteínas; CIB-CSIC; C/Ramiro denMaeztu 9 28040 Madrid Spain
| | - Sabine André
- Institut für Physiologische Chemie; Tierärztliche Fakultät; Ludwig-Maximilians-Universität München; Veterinärstrasse 13 80539 München Germany
| | - Hans-Joachim Gabius
- Institut für Physiologische Chemie; Tierärztliche Fakultät; Ludwig-Maximilians-Universität München; Veterinärstrasse 13 80539 München Germany
| | - Ángel Rumbero
- Department of Organic Chemistry; Faculty of Science; Autonoma University of Madrid; Spain
| | - Jesús Jiménez-Barbero
- Departamento de Ciencia de Proteínas; CIB-CSIC; C/Ramiro denMaeztu 9 28040 Madrid Spain
- Ikerbasque; Basque Foundation for Science; Maria Diaz de Haro 13 48009 Bilbao Spain
- Department of Organic Chemistry II, Faculty of Science & Technology; University of the Basque Country; 48940 Leioa Bizkaia Spain
| | - Wolf-Dieter Fessner
- Department of Organic Chemistry and Biochemistry; Technische Universität Darmstadt, A; larich-Weiss-Strasse 4 64287 Darmstadt Germany
| | - María J. Hernáiz
- Department of Organic and Pharmaceutical Chemistry; Faculty of Pharmacy; Complutense University; Plaza Ramón y CajaL s/n 28040 Madrid Spain
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Allegretti AS, Ortiz G, Kalim S, Wibecan J, Zhang D, Shan HY, Xu D, Chung RT, Karumanchi SA, Thadhani RI. Siglec-7 as a Novel Biomarker to Predict Mortality in Decompensated Cirrhosis and Acute Kidney Injury. Dig Dis Sci 2016; 61:3609-3620. [PMID: 27655105 PMCID: PMC5106324 DOI: 10.1007/s10620-016-4316-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Accepted: 09/13/2016] [Indexed: 12/22/2022]
Abstract
BACKGROUND Patients with decompensated cirrhosis have high morbidity and are commonly hospitalized with acute kidney injury. AIMS We examined serum levels of Siglec-7, a transmembrane receptor that regulates immune activity, as a biomarker for mortality in patients with cirrhosis and acute kidney injury. METHODS Serum Siglec-7 was measured in hospitalized patients with cirrhosis and acute kidney injury, as well as in reference groups with acute liver injury/acute kidney injury, cirrhosis without acute kidney injury, and sepsis without liver disease. Clinical characteristics and subsequent outcomes were examined using univariate and multivariable analyses according to initial Siglec-7 levels. Primary outcome was death by 90 days. RESULTS One hundred twenty-eight subjects were included, 92 of which had cirrhosis and acute kidney injury and were used in the primary analysis. Average Model for End-Stage Liver Disease (MELD) score was 24 [95 % CI 23, 26], and serum creatinine was 2.5 [2.2, 2.8] mg/dL at the time Siglec-7 was measured. After adjusting for age and MELD score, high serum Siglec-7 level predicted mortality with a hazard ratio of 1.96 [1.04, 3.69; p = 0.04]. There was no difference in Siglec-7 levels by etiology of AKI (p = 0.24). Addition of serum Siglec-7 to MELD score improved discrimination for 90-day mortality [category-free net reclassification index = 0.38 (p = 0.04); integrated discrimination increment = 0.043 (p = 0.04)]. CONCLUSION Serum Siglec-7 was associated with increased mortality among hospitalized patients with cirrhosis and acute kidney injury. Addition of Siglec-7 to MELD score may increase discrimination to predict 90-day mortality.
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Affiliation(s)
- Andrew S. Allegretti
- Division of Nephrology, Department of Medicine, Massachusetts General Hospital, Boston, MA, USA
| | - Guillermo Ortiz
- Department of Medicine, St. Elizabeth’s Hospital, Boston, MA, USA
| | - Sahir Kalim
- Division of Nephrology, Department of Medicine, Massachusetts General Hospital, Boston, MA, USA
| | - Joshua Wibecan
- Division of Nephrology, Department of Medicine, Massachusetts General Hospital, Boston, MA, USA
| | - Dongsheng Zhang
- Division of Nephrology, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA, USA
| | - Hui Yi Shan
- Division of Nephrology and Hypertension, Department of Medicine, Keck School of Medicine of USC, Los Angeles, CA, USA
| | - Dihua Xu
- Division of Nephrology, Department of Medicine, Massachusetts General Hospital, Boston, MA, USA
| | - Raymond T. Chung
- Liver Center and Gastrointestinal Division, Department of Medicine, Massachusetts General Hospital, Boston, MA, USA
| | - S. Ananth Karumanchi
- Division of Nephrology, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA, USA
| | - Ravi I. Thadhani
- Division of Nephrology, Department of Medicine, Massachusetts General Hospital, Boston, MA, USA
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Hassan MI, Lundgren BR, Chaumun M, Whitfield DM, Clark B, Schoenhofen IC, Boddy CN. Total Biosynthesis of Legionaminic Acid, a Bacterial Sialic Acid Analogue. Angew Chem Int Ed Engl 2016; 55:12018-21. [PMID: 27538580 DOI: 10.1002/anie.201606006] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Indexed: 02/03/2023]
Abstract
Legionaminic acid, Leg5,7Ac2 , a nonulosonic acid like 5-acetamido neuraminic acid (Neu5Ac, sialic acid), is found in cell surface glycoconjugates of bacteria including the pathogens Campylobacter jejuni, Acinetobacter baumanii and Legionella pneumophila. The presence of Leg5,7Ac2 has been correlated with virulence in humans by mechanisms that likely involve subversion of the host's immune system or interactions with host cell surfaces due to its similarity to Neu5Ac. Investigation into its role in bacterial physiology and pathogenicity is limited as there are no effective sources of it. Herein, we construct a de novo Leg5,7Ac2 biosynthetic pathway by combining multiple metabolic modules from three different microbial sources (Saccharomyces cerevisiae, C. jejuni, and L. pneumophila). Over-expression of this de novo pathway in Escherichia coli that has been engineered to lack two native catabolic pathways, enables significant quantities of Leg5,7Ac2 (≈120 mg L(-1) of culture broth) to be produced. Pure Leg5,7Ac2 could be isolated and converted into CMP-activated sugar for biochemical applications and a phenyl thioglycoside for chemical synthesis applications. This first total biosynthesis provides an essential source of Leg5,7Ac2 enabling study of its role in prokaryotic and eukaryotic glycobiology.
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Affiliation(s)
- Mohamed I Hassan
- Department of Chemistry and Biomolecular Sciences, Centre for Chemical and Synthetic Biology, University of Ottawa, Ottawa, ON, K1N 6N5, Canada
| | - Benjamin R Lundgren
- Department of Chemistry and Biomolecular Sciences, Centre for Chemical and Synthetic Biology, University of Ottawa, Ottawa, ON, K1N 6N5, Canada
| | - Michael Chaumun
- Department of Chemistry and Biomolecular Sciences, Centre for Chemical and Synthetic Biology, University of Ottawa, Ottawa, ON, K1N 6N5, Canada
| | | | - Brady Clark
- Sussex Research Laboratories Inc., Ottawa, ON, K1A 0R6, Canada
| | - Ian C Schoenhofen
- Human Health Therapeutics Portfolio, National Research Council Canada, Ottawa, ON, K1A 0R6, Canada.
| | - Christopher N Boddy
- Department of Chemistry and Biomolecular Sciences, Centre for Chemical and Synthetic Biology, University of Ottawa, Ottawa, ON, K1N 6N5, Canada.
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Schofield CL, Marín MJ, Rejzek M, Crocker PR, Field RA, Russell DA. Detection of mSiglec-E, in solution and expressed on the surface of Chinese hamster ovary cells, using sialic acid functionalised gold nanoparticles. Analyst 2016; 141:5799-5809. [PMID: 27537280 DOI: 10.1039/c6an01230b] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Sialic acids are widespread in biology, fulfilling a wide range of functions. Their cognate lectin receptors - Siglecs - are equally diverse and widely distributed, with different Siglecs found within distinct populations of cells in the haemopoietic, immune and nervous systems. A convenient way to assay ligand recognition of soluble Siglecs would be useful, as would methods for the concomitant assessment of Siglec distribution on cell surfaces. Here we report the use of gold nanoparticles functionalised with a sialic acid ligand diluted with a polyethylene glycol (PEG) ligand for the plasmonic detection of a soluble form of murine Siglec-E (mSiglec-E-Fc fusion protein) and, importantly, for the specific detection of the same Siglec expressed on the surface of mammalian cells. These sialic acid functionalised nanoparticles are shown to overcome problems such as cellular cis interactions and low Siglec-ligand affinity. The gold nanoparticles were functionalised with various ratios of sialic acid : PEG ligands and the optimum ratio for the detection of murine Siglec-E was established based on the plasmonic detection of the soluble pre-complexed recombinant form of murine Siglec-E (mSiglec-E-Fc fusion protein). The optimum ratio for the detection of the fusion protein was found to be sialic acid : PEG ligands in a 50 : 50 ratio (glyconanoparticles 1). The optimised glyconanoparticles 1 were used to recognise and bind to the murine Siglec-E expressed on the surface of transfected Chinese hamster ovary cells as determined by transmission electron microscopy.
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Affiliation(s)
- Claire L Schofield
- School of Chemistry, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK.
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69
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Structural basis for sulfation-dependent self-glycan recognition by the human immune-inhibitory receptor Siglec-8. Proc Natl Acad Sci U S A 2016; 113:E4170-9. [PMID: 27357658 DOI: 10.1073/pnas.1602214113] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Siglec-8 is a human immune-inhibitory receptor that, when engaged by specific self-glycans, triggers eosinophil apoptosis and inhibits mast cell degranulation, providing an endogenous mechanism to down-regulate immune responses of these central inflammatory effector cells. Here we used solution NMR spectroscopy to dissect the fine specificity of Siglec-8 toward different sialylated and sulfated carbohydrate ligands and determined the structure of the Siglec-8 lectin domain in complex with its prime glycan target 6'-sulfo sialyl Lewis(x) A canonical motif for sialic acid recognition, extended by a secondary motif formed by unique loop regions, recognizing 6-O-sulfated galactose dictates tight specificity distinct from other Siglec family members and any other endogenous glycan recognition receptors. Structure-guided mutagenesis revealed key contacts of both interfaces to be equally essential for binding. Our work provides critical structural and mechanistic insights into how Siglec-8 selectively recognizes its glycan target, rationalizes the functional impact of site-specific glycan sulfation in modulating this lectin-glycan interaction, and will enable the rational design of Siglec-8-targeted agonists to treat eosinophil- and mast cell-related allergic and inflammatory diseases, such as asthma.
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70
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Spence S, Greene MK, Fay F, Hams E, Saunders SP, Hamid U, Fitzgerald M, Beck J, Bains BK, Smyth P, Themistou E, Small DM, Schmid D, O'Kane CM, Fitzgerald DC, Abdelghany SM, Johnston JA, Fallon PG, Burrows JF, McAuley DF, Kissenpfennig A, Scott CJ. Targeting Siglecs with a sialic acid-decorated nanoparticle abrogates inflammation. Sci Transl Med 2016; 7:303ra140. [PMID: 26333936 DOI: 10.1126/scitranslmed.aab3459] [Citation(s) in RCA: 128] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Sepsis is the most frequent cause of death in hospitalized patients, and severe sepsis is a leading contributory factor to acute respiratory distress syndrome (ARDS). At present, there is no effective treatment for these conditions, and care is primarily supportive. Murine sialic acid-binding immunoglobulin-like lectin-E (Siglec-E) and its human orthologs Siglec-7 and Siglec-9 are immunomodulatory receptors found predominantly on hematopoietic cells. These receptors are important negative regulators of acute inflammatory responses and are potential targets for the treatment of sepsis and ARDS. We describe a Siglec-targeting platform consisting of poly(lactic-co-glycolic acid) nanoparticles decorated with a natural Siglec ligand, di(α2→8) N-acetylneuraminic acid (α2,8 NANA-NP). This nanoparticle induced enhanced oligomerization of the murine Siglec-E receptor on the surface of macrophages, unlike the free α2,8 NANA ligand. Furthermore, treatment of murine macrophages with these nanoparticles blocked the production of lipopolysaccharide-induced inflammatory cytokines in a Siglec-E-dependent manner. The nanoparticles were also therapeutically beneficial in vivo in both systemic and pulmonary murine models replicating inflammatory features of sepsis and ARDS. Moreover, we confirmed the anti-inflammatory effect of these nanoparticles on human monocytes and macrophages in vitro and in a human ex vivo lung perfusion (EVLP) model of lung injury. We also established that interleukin-10 (IL-10) induced Siglec-E expression and α2,8 NANA-NP further augmented the expression of IL-10. Indeed, the effectiveness of the nanoparticle depended on IL-10. Collectively, these results demonstrated a therapeutic effect of targeting Siglec receptors with a nanoparticle-based platform under inflammatory conditions.
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Affiliation(s)
- Shaun Spence
- Centre for Infection and Immunity, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast BT9 7AE, UK
| | | | - François Fay
- School of Pharmacy, Queen's University Belfast, Belfast BT9 7BL, UK. Translational and Molecular Imaging Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Emily Hams
- Trinity Biomedical Sciences Institute, School of Medicine, Trinity College Dublin, Dublin 2, Ireland
| | - Sean P Saunders
- Trinity Biomedical Sciences Institute, School of Medicine, Trinity College Dublin, Dublin 2, Ireland
| | - Umar Hamid
- Centre for Infection and Immunity, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast BT9 7AE, UK
| | - Marianne Fitzgerald
- Centre for Infection and Immunity, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast BT9 7AE, UK
| | - Jonathan Beck
- Centre for Infection and Immunity, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast BT9 7AE, UK
| | | | - Peter Smyth
- School of Pharmacy, Queen's University Belfast, Belfast BT9 7BL, UK
| | - Efrosyni Themistou
- School of Chemistry and Chemical Engineering, Queen's University Belfast, Belfast BT9 5AG, UK
| | - Donna M Small
- Centre for Infection and Immunity, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast BT9 7AE, UK
| | - Daniela Schmid
- School of Pharmacy, Queen's University Belfast, Belfast BT9 7BL, UK
| | - Cecilia M O'Kane
- Centre for Infection and Immunity, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast BT9 7AE, UK
| | - Denise C Fitzgerald
- Centre for Infection and Immunity, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast BT9 7AE, UK
| | - Sharif M Abdelghany
- School of Pharmacy, Queen's University Belfast, Belfast BT9 7BL, UK. Faculty of Pharmacy, University of Jordan, Amman 11942, Jordan
| | - James A Johnston
- Centre for Infection and Immunity, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast BT9 7AE, UK. Inflammation Research, Amgen Inc., Thousand Oaks, CA 91320, USA
| | - Padraic G Fallon
- Trinity Biomedical Sciences Institute, School of Medicine, Trinity College Dublin, Dublin 2, Ireland. National Children's Research Centre, Our Lady's Children's Hospital, Dublin 12, Ireland
| | - James F Burrows
- School of Pharmacy, Queen's University Belfast, Belfast BT9 7BL, UK
| | - Daniel F McAuley
- Centre for Infection and Immunity, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast BT9 7AE, UK
| | - Adrien Kissenpfennig
- Centre for Infection and Immunity, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast BT9 7AE, UK
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71
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St-Pierre G, Pal S, Østergaard ME, Zhou T, Yu J, Tanowitz M, Seth PP, Hanessian S. Synthesis and biological evaluation of sialyl-oligonucleotide conjugates targeting leukocyte B trans-membranal receptor CD22 as delivery agents for nucleic acid drugs. Bioorg Med Chem 2016; 24:2397-2409. [PMID: 27117693 DOI: 10.1016/j.bmc.2016.03.047] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Revised: 03/16/2016] [Accepted: 03/27/2016] [Indexed: 01/27/2023]
Abstract
Antisense oligonucleotides (ASOs) modified with ligands which target cell surface receptors have the potential to significantly improve potency in the target tissue. This has recently been demonstrated using triantennary N-acetyl d-galactosamine conjugated ASOs. CD22 is a cell surface receptor expressed exclusively on B cells thus presenting an attractive target for B cell specific delivery of drugs. Herein, we reported the synthesis of monovalent and trivalent ASO conjugates with biphenylcarbonyl (BPC) modified sialic acids and their study as ASO delivery agents into B cells. CD22 positive cells exhibited reduced potency when treated with ligand modified ASOs and mechanistic examination suggested reduced uptake into cells potentially as a result of sequestration of ASO by other cell-surface proteins.
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Affiliation(s)
- Gabrielle St-Pierre
- Department of Chemistry, Université de Montréal, PO Box 6128, Succ., Centre-ville, Montréal, Québec H3C 3J7, Canada
| | - Sudip Pal
- Department of Chemistry, Université de Montréal, PO Box 6128, Succ., Centre-ville, Montréal, Québec H3C 3J7, Canada
| | - Michael E Østergaard
- Medicinal Chemistry, Ionis Pharmaceuticals, Inc., 2855 Gazelle Court, Carlsbad, CA 92010, United States
| | - Tianyuan Zhou
- Medicinal Chemistry, Ionis Pharmaceuticals, Inc., 2855 Gazelle Court, Carlsbad, CA 92010, United States
| | - Jinghua Yu
- Medicinal Chemistry, Ionis Pharmaceuticals, Inc., 2855 Gazelle Court, Carlsbad, CA 92010, United States
| | - Michael Tanowitz
- Medicinal Chemistry, Ionis Pharmaceuticals, Inc., 2855 Gazelle Court, Carlsbad, CA 92010, United States
| | - Punit P Seth
- Medicinal Chemistry, Ionis Pharmaceuticals, Inc., 2855 Gazelle Court, Carlsbad, CA 92010, United States.
| | - Stephen Hanessian
- Department of Chemistry, Université de Montréal, PO Box 6128, Succ., Centre-ville, Montréal, Québec H3C 3J7, Canada.
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Schnaar RL. Glycobiology simplified: diverse roles of glycan recognition in inflammation. J Leukoc Biol 2016; 99:825-38. [PMID: 27004978 DOI: 10.1189/jlb.3ri0116-021r] [Citation(s) in RCA: 92] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Accepted: 02/18/2016] [Indexed: 12/30/2022] Open
Abstract
Glycans and complementary glycan-binding proteins are essential components in the language of cell-cell interactions in immunity. The study of glycan function is the purview of glycobiology, which has often been presented as an unusually complex discipline. In fact, the human glycome, composed of all of its glycans, is built primarily from only 9 building blocks that are combined by enzymes (writers) with specific and limited biosynthetic capabilities into a tractable and increasingly accessible number of potential glycan patterns that are functionally read by several dozen human glycan-binding proteins (readers). Nowhere is the importance of glycan recognition better understood than in infection and immunity, and knowledge in this area has already led to glycan mimetic anti-infective and anti-inflammatory drugs. This review includes a brief tutorial on human glycobiology and a limited number of specific examples of glycan-binding protein-glycan interactions that initiate and regulate inflammation. Examples include representatives from different glycan-binding protein families, including the C-type lectins (E-selectin, P-selectin, dectin-1, and dectin-2), sialic acid-binding immunoglobulin-like lectins (sialic acid-binding immunoglobulin-like lectins 8 and 9), galectins (galectin-1, galectin-3, and galectin-9), as well as hyaluronic acid-binding proteins. As glycoscience technologies advance, opportunities for enhanced understanding of glycans and their roles in leukocyte cell biology provide increasing opportunities for discovery and therapeutic intervention.
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Affiliation(s)
- Ronald L Schnaar
- Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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73
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Cao Y, Liu H, Zhang H, Lin C, Li R, Zhang W, Shen Z, Xu J. Decreased expression of Siglec-8 associates with poor prognosis in patients with gastric cancer after surgical resection. Tumour Biol 2016; 37:10883-91. [PMID: 26883254 DOI: 10.1007/s13277-016-4859-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Accepted: 01/13/2016] [Indexed: 10/22/2022] Open
Abstract
The expression of sialic acid-binding Ig-like lectin (Siglec) family has been detected in many malignant tumors and correlated with patient outcomes. The present study aims to investigate the prognostic value of Siglec-8 expression and refine current risk stratification system in patients with gastric cancer. Two independent sets of patients (n = 78; n = 356, respectively) with gastric cancer from Zhongshan Hospital were enrolled into this study. The expression of Siglec-8 was detected by immunohistochemistry. Cox regression analysis was used to assess the prognostic value of Siglec-8 expression and clinical outcomes. A novel molecular prognostic stratification system combining intratumoral Siglec-8 expression with TNM stage was determined by means of receiver operating characteristic analysis. Multivariate Cox regression analysis identified that intratumoral Siglec-8 low expression was an independent prognostic factor for dismal overall survival of patients with gastric cancer. Incorporating intratumoral Siglec-8 expression into the current TNM staging system showed more accuracy for predicting prognosis of patients with gastric cancer. Our study suggested that intratumoral Siglec-8 expression was an independent prognostic factor for overall survival of patients with gastric cancer. Incorporating Siglec-8 expression level into current TNM staging system might add more comprehensive prognostic information for patients with gastric cancer and lead to a more precise risk stratification system for predicting clinical outcomes.
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Affiliation(s)
- Yifan Cao
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, 200032, China
| | - Hao Liu
- Department of General Surgery, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
| | - Heng Zhang
- Department of General Surgery, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
| | - Chao Lin
- Department of General Surgery, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
| | - Ruochen Li
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, 200032, China
| | - Weijuan Zhang
- Department of Immunology, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Zhenbin Shen
- Department of General Surgery, Zhongshan Hospital, Fudan University, Shanghai, 200032, China.
| | - Jiejie Xu
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, 200032, China.
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74
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Sialic acids in biological and therapeutic processes: opportunities and challenges. Future Med Chem 2015; 7:2285-99. [DOI: 10.4155/fmc.15.135] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
It is now well documented that carbohydrates play multiple roles in biological processes, and hence are interesting targets for chemical biology and medicinal chemistry programs. This review focuses on a subset of carbohydrates, specifically sialic acid containing carbohydrates. It highlights their occurrence and diversity, and presents evidence for their roles in a range of biological pathways. It illustrates that they are targets for novel medicinal chemistry strategies for a range of therapeutic areas, including cancer and immunity. Case studies highlight opportunities and challenges in this area, and sialic acid-based drugs that have entered clinical practice and are promising candidates for future disease intervention schemes, are discussed. The review concludes by highlighting perspectives and emerging roles for these targets.
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Yilmaz M, Richard S, Jabbour E. The clinical potential of inotuzumab ozogamicin in relapsed and refractory acute lymphocytic leukemia. Ther Adv Hematol 2015; 6:253-61. [PMID: 26425338 DOI: 10.1177/2040620715596715] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Antibody-drug conjugates (ADCs) are likely to make a significant contribution in the treatment of acute lymphoblastic leukemia (ALL) by combining the cytotoxicity of chemotherapy with the specificity of monoclonal antibodies. CD22, an endocytic receptor expressed by the majority of B cells, is an excellent target for ADCs. Inotuzumab ozogamicin (INO) is an ADC that consists of a cytotoxic moiety (derivative of calicheamicin) attached to a humanized monoclonal anti-CD22 antibody. As a single agent, INO, was shown to be effective with an objective response rate of 50% in the treatment of relapsed and refractory CD22 positive ALL patients. Clinical trials investigating the combination of INO with the conventional chemotherapies are ongoing. This review summarizes the clinical potential of INO in treatment of relapsed and refractory ALL, based on currently available data in the literature.
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Affiliation(s)
- Musa Yilmaz
- Department of Hematology and Oncology, Baylor College of Medicine, Houston, TX, USA
| | - Samantha Richard
- Department of Leukemia, The University of Texas M. D. Anderson Cancer Center, Houston, TX, USA
| | - Elias Jabbour
- Department of Leukemia, The University of Texas M. D. Anderson Cancer Center, Box 428, 1515 Holcombe Blvd., Houston, TX 77030, USA
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Chang CH, Wang Y, Gupta P, Goldenberg DM. Extensive crosslinking of CD22 by epratuzumab triggers BCR signaling and caspase-dependent apoptosis in human lymphoma cells. MAbs 2015; 7:199-211. [PMID: 25484043 PMCID: PMC4622945 DOI: 10.4161/19420862.2014.979081] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Epratuzumab has demonstrated therapeutic activity in patients with non-Hodgkin lymphoma, acute lymphoblastic leukemia, systemic lupus erythematosus, and Sjögren's syndrome, but its mechanism of affecting normal and malignant B cells remains incompletely understood. We reported previously that epratuzumab displayed in vitro cytotoxicity to CD22-expressing Burkitt lymphoma cell lines (Daudi and Ramos) only when immobilized on plates or combined with a crosslinking antibody plus a suboptimal amount of anti-IgM (1 μg/mL). Herein, we show that, in the absence of additional anti-IgM ligation, extensive crosslinking of CD22 by plate-immobilized epratuzumab induced intracellular changes in Daudi cells similar to ligating B-cell antigen receptor with a sufficiently high amount of anti-IgM (10 μg/mL). Specifically, either treatment led to phosphorylation of CD22, CD79a and CD79b, along with their translocation to lipid rafts, both of which were essential for effecting caspase-dependent apoptosis. Moreover, such immobilization induced stabilization of F-actin, phosphorylation of Lyn, ERKs and JNKs, generation of reactive oxygen species (ROS), decrease in mitochondria membrane potential (Δψm), upregulation of pro-apoptotic Bax, and downregulation of anti-apoptotic Bcl-xl and Mcl-1. The physiological relevance of immobilized epratuzumab was implicated by noting that several of its in vitro effects, including apoptosis, drop in Δψm, and generation of ROS, could be observed with soluble epratuzumab in Daudi cells co-cultivated with human umbilical vein endothelial cells. These results suggest that the in vivo mechanism of non-ligand-blocking epratuzumab may, in part, involve the unmasking of CD22 to facilitate the trans-interaction of B cells with vascular endothelium.
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Key Words
- 488-annexin V, Alexa Fluor 488-conjugated annexin V
- 7-AAD, 7-aminoactinomycin D, Syk, spleen tyrosine kinase
- Anti-IgM, F(ab’)2 fragment of affinity-purified goat anti-human IgM, Fc5μ fragment
- BCR
- BCR, B-cell antigen receptor
- BSA, bovine serum albumin
- CD22
- CM-H2DCF-DA, 2′,7′-dichlorodihydrofluorescein diacetate
- DNP, 2,4-dinitrophenyl
- EC, endothelial cells
- ERKs, extracellular signal-regulated kinases
- FBS, fetal bovine serum
- FITC-DNase I, fluorescein isothiocyanate-conjugated DNase I
- GAH, F(ab′)2 fragment of affinity-purified goat anti-human IgG Fcγ fragment-specific
- HUV-EC
- HUV-EC, human umbilical vein endothelial cells
- ITIM, immunoreceptor tyrosine-based inhibition motif
- JNKs, c-Jun N-terminal kinases
- JP, jasplakinolide
- LatB, latrunculin B
- Lyn, Lck/Yes novel tyrosine kinase
- MAP kinases, mitogen-activated protein kinases
- MTS, (3-(4, 5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium
- PARP, poly(ADP-ribose) polymerase
- PBS, phosphate-buffered saline
- PLCγ2, phospholipase C, isotype gamma 2
- ROS, reactive oxygen species
- Rhodamine-anti-IgG, rhodamine-conjugated F(ab′)2 fragment of affinity-purified goat anti-human IgG, F(ab′)2 fragment-specific
- TMRE/tetramethylrhodamine/ethyl ester
- epratuzumab
- human B-cell lymphoma
- immobilized
- mIgM, membrane IgM
- Δψm, mitochondria membrane potential
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A Peptide Mimetic of 5-Acetylneuraminic Acid-Galactose Binds with High Avidity to Siglecs and NKG2D. PLoS One 2015; 10:e0130532. [PMID: 26110603 PMCID: PMC4482410 DOI: 10.1371/journal.pone.0130532] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2013] [Accepted: 05/21/2015] [Indexed: 01/01/2023] Open
Abstract
We previously identified several peptide sequences that mimicked the terminal sugars of complex glycans. Using plant lectins as analogs of lectin-type cell-surface receptors, a tetravalent form of a peptide with the sequence NPSHPLSG, designated svH1C, bound with high avidity to lectins specific for glycans with terminal 5-acetylneuraminic acid (Neu5Ac)-galactose (Gal)/N-acetylgalactosamine (GalNAc) sequences. In this report, we show by circular dichroism and NMR spectra that svH1C lacks an ordered structure and thus interacts with binding sites from a flexible conformation. The peptide binds with high avidity to several recombinant human siglec receptors that bind preferentially to Neu5Ac(α2,3)Gal, Neu5Ac(α2,6)GalNAc or Neu5Ac(α2,8)Neu5Ac ligands. In addition, the peptide bound the receptor NKG2D, which contains a lectin-like domain that binds Neu5Ac(α2,3)Gal. The peptide bound to these receptors with a KD in the range of 0.6 to 1 μM. Binding to these receptors was inhibited by the glycoprotein fetuin, which contains multiple glycans that terminate in Neu5Ac(α2,3)Gal or Neu5Ac(α2,6)Gal, and by sialyllactose. Binding of svH1C was not detected with CLEC9a, CLEC10a or DC-SIGN, which are lectin-type receptors specific for other sugars. Incubation of neuraminidase-treated human peripheral blood mononuclear cells with svH1C resulted in binding of the peptide to a subset of the CD14+ monocyte population. Tyrosine phosphorylation of siglecs decreased dramatically when peripheral blood mononuclear cells were treated with 100 nM svH1C. Subcutaneous, alternate-day injections of svH1C into mice induced several-fold increases in populations of several types of immune cells in the peritoneal cavity. These results support the conclusion that svH1C mimics Neu5Ac-containing sequences and interacts with cell-surface receptors with avidities sufficient to induce biological responses at low concentrations. The attenuation of inhibitory receptors suggests that svH1C has characteristics of a checkpoint inhibitor.
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78
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Fernández-Tejada A, Cañada FJ, Jiménez-Barbero J. Recent Developments in Synthetic Carbohydrate-Based Diagnostics, Vaccines, and Therapeutics. Chemistry 2015; 21:10616-28. [PMID: 26095198 DOI: 10.1002/chem.201500831] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Glycans are everywhere in biological systems, being involved in many cellular events with important implications for medical purposes. Building upon a detailed understanding of the functional roles of carbohydrates in molecular recognition processes and disease states, glycans are increasingly being considered as key players in pharmacological research. On the basis of the important progress recently made in glycochemistry, glycobiology, and glycomedicine, we provide a complete overview of successful applications and future perspectives of carbohydrates in the biopharmaceutical and medical fields. This review highlights the development of carbohydrate-based diagnostics, exemplified by glycan imaging techniques and microarray platforms, synthetic oligosaccharide vaccines against infectious diseases (e.g., HIV) and cancer, and finally carbohydrate-derived therapeutics, including glycomimetic drugs and glycoproteins.
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Affiliation(s)
| | - F Javier Cañada
- Chemical and Physical Biology, CIB-CSIC, Ramiro de Maeztu 9, 28040 Madrid (Spain)
| | - Jesús Jiménez-Barbero
- Infectious Disease Programme, Center for Cooperative Research in Biosciences, CIC-bioGUNE, Bizkaia Technology Park, 48160 Derio (Spain). .,Ikerbasque, Basque Foundation for Science, María López de Haro 13, 48009 Bilbao (Spain).
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79
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Boligan KF, Mesa C, Fernandez LE, von Gunten S. Cancer intelligence acquired (CIA): tumor glycosylation and sialylation codes dismantling antitumor defense. Cell Mol Life Sci 2015; 72:1231-48. [PMID: 25487607 PMCID: PMC11113383 DOI: 10.1007/s00018-014-1799-5] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Revised: 11/27/2014] [Accepted: 12/01/2014] [Indexed: 01/28/2023]
Abstract
Aberrant glycosylation is a key feature of malignant transformation and reflects epigenetic and genetic anomalies among the multitude of molecules involved in glycan biosynthesis. Although glycan biosynthesis is not template bound, altered tumor glycosylation is not random, but associated with common glycosylation patterns. Evidence suggests that acquisition of distinct glycosylation patterns evolves from a 'microevolutionary' process conferring advantages in terms of tumor growth, tumor dissemination, and immune escape. Such glycosylation modifications also involve xeno- and hypersialylation. Xeno-autoantigens such as Neu5Gc-gangliosides provide potential targets for immunotherapy. Hypersialylation may display 'enhanced self' to escape immunosurveillance and involves several not mutually exclusive inhibitory pathways that all rely on protein-glycan interactions. A better understanding of tumor 'glycan codes' as deciphered by lectins, such as siglecs, selectins, C-type lectins and galectins, may lead to novel treatment strategies, not only in cancer, but also in autoimmune disease or transplantation.
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Affiliation(s)
- Kayluz Frias Boligan
- Institute of Pharmacology, University of Bern, Friedbühlstrasse 49, 3010, Bern, Switzerland,
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80
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Cognasse F, Nguyen KA, Damien P, McNicol A, Pozzetto B, Hamzeh-Cognasse H, Garraud O. The Inflammatory Role of Platelets via Their TLRs and Siglec Receptors. Front Immunol 2015; 6:83. [PMID: 25784910 PMCID: PMC4345914 DOI: 10.3389/fimmu.2015.00083] [Citation(s) in RCA: 141] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Accepted: 02/12/2015] [Indexed: 12/16/2022] Open
Abstract
Platelets are non-nucleated cells that play central roles in the processes of hemostasis, innate immunity, and inflammation; however, several reports show that these distinct functions are more closely linked than initially thought. Platelets express numerous receptors and contain hundreds of secretory products. These receptors and secretory products are instrumental to the platelet functional responses. The capacity of platelets to secrete copious amounts of cytokines, chemokines, and related molecules appears intimately related to the role of the platelet in inflammation. Platelets exhibit non-self-infectious danger detection molecules on their surfaces, including those belonging to the “toll-like receptor” family, as well as pathogen sensors of other natures (Ig- or complement receptors, etc.). These receptors permit platelets to both bind infectious agents and deliver differential signals leading to the secretion of cytokines/chemokines, under the control of specific intracellular regulatory pathways. In contrast, dysfunctional receptors or dysregulation of the intracellular pathway may increase the susceptibility to pathological inflammation. Physiological vs. pathological inflammation is tightly controlled by the sensors of danger expressed in resting, as well as in activated, platelets. These sensors, referred to as pathogen recognition receptors, primarily sense danger signals termed pathogen associated molecular patterns. As platelets are found in inflamed tissues and are involved in auto-immune disorders, it is possible that they can also be stimulated by internal pathogens. In such cases, platelets can also sense danger signals using damage associated molecular patterns (DAMPs). Some of the most significant DAMP family members are the alarmins, to which the Siglec family of molecules belongs. This review examines the role of platelets in anti-infection immunity via their TLRs and Siglec receptors.
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Affiliation(s)
- Fabrice Cognasse
- Etablissement Français du Sang Auvergne-Loire , Saint-Etienne , France ; GIMAP-EA3064, Université de Lyon , Saint Etienne , France
| | - Kim Anh Nguyen
- GIMAP-EA3064, Université de Lyon , Saint Etienne , France
| | - Pauline Damien
- GIMAP-EA3064, Université de Lyon , Saint Etienne , France
| | - Archibald McNicol
- Faculty of Health Sciences, Colleges of Pharmacy and Medicine, University of Manitoba , Winnipeg, MB , Canada
| | - Bruno Pozzetto
- GIMAP-EA3064, Université de Lyon , Saint Etienne , France
| | | | - Olivier Garraud
- GIMAP-EA3064, Université de Lyon , Saint Etienne , France ; Institut National de Transfusion Sanguine (INTS) , Paris , France
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81
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Pröpster JM, Yang F, Ernst B, Allain FHT, Schubert M. Functional Siglec lectin domains from soluble expression in the cytoplasm of Escherichia coli. Protein Expr Purif 2015; 109:14-22. [PMID: 25623398 DOI: 10.1016/j.pep.2015.01.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Revised: 01/09/2015] [Accepted: 01/19/2015] [Indexed: 01/25/2023]
Abstract
Siglecs (sialic acid-binding immunoglobulin-like lectins) are a family of mammalian cell-surface receptors that are involved in cell-cell interactions and signaling functions, primarily expressed on cells of the immune system. Key to their function is their specific binding of distinct sialylated glycan ligands mediated via an N-terminal carbohydrate recognition (lectin) domain. Studies concerning the molecular basis of their individual carbohydrate specificities are rare due to the absence of suitable recombinant expression methods for producing these disulfide-containing proteins in sufficient quantities required for their in-depth in vitro characterization. We established an efficient E. coli-based expression and purification method for Siglec lectin domains, utilizing the trxB gor suppressor strain Rosetta-gami B (DE3) in which proper folding with intact disulfide bonds was achieved in the cytoplasm. The approach is demonstrated for human Siglec-7, -8 and -9 lectin domains and works equally well for expression in nutrient-rich (LB) or minimal growth medium, allowing stable-isotope labeling for NMR studies. The recombinant proteins were properly folded as proven by 2D (1)H-(15)N HSQC NMR spectroscopy and by thermal unfolding followed by CD spectroscopy, and functionally active as confirmed by monitoring ligand binding using NMR titration experiments. Our method enables efficient production of homogeneous and active protein samples in milligram quantities. Its implementation will significantly enhance future structure-function studies of this important class of immune-modulating receptors and will support a variety of applications including screening for natural and synthetic ligands or the development of fluorescently-labeled molecular tools for glycan ligand detection or flow-cytometric cell sorting.
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Affiliation(s)
- Johannes M Pröpster
- Institute of Molecular Biology and Biophysics, ETH Zürich, CH-8093 Zürich, Switzerland
| | - Fan Yang
- Institute of Molecular Pharmacy, Pharmacenter, University of Basel, CH-4056 Basel, Switzerland; Department of Molecular & Medical Pharmacology, David Geffen School of Medicine at UCLA, CA 90095, USA(1)
| | - Beat Ernst
- Institute of Molecular Pharmacy, Pharmacenter, University of Basel, CH-4056 Basel, Switzerland
| | - Frédéric H-T Allain
- Institute of Molecular Biology and Biophysics, ETH Zürich, CH-8093 Zürich, Switzerland.
| | - Mario Schubert
- Institute of Molecular Biology and Biophysics, ETH Zürich, CH-8093 Zürich, Switzerland; Department of Molecular Biology, University of Salzburg, A-5020 Salzburg, Austria(1).
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82
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Bochner BS, Zimmermann N. Role of siglecs and related glycan-binding proteins in immune responses and immunoregulation. J Allergy Clin Immunol 2015; 135:598-608. [PMID: 25592986 DOI: 10.1016/j.jaci.2014.11.031] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Revised: 11/14/2014] [Accepted: 11/25/2014] [Indexed: 12/16/2022]
Abstract
Virtually all cells and extracellular material are heavily decorated by various glycans, yet our understanding of the structure and function of these moieties lags behind the understanding of nucleic acids, lipids, and proteins. Recent years have seen a tremendous acceleration of knowledge in the field of glycobiology, revealing many intricacies and functional contributions that were previously poorly appreciated or even unrecognized. This review highlights several topics relevant to glycoimmunology in which mammalian and pathogen-derived glycans displayed on glycoproteins and other scaffolds are recognized by specific glycan-binding proteins (GBPs), leading to a variety of proinflammatory and anti-inflammatory cellular responses. The focus for this review is mainly on 2 families of GBPs, sialic acid-binding immunoglobulin-like lectins (siglecs) and selectins, that are involved in multiple steps of the immune response, including distinguishing pathogens from self, cell trafficking to sites of inflammation, fine-tuning of immune responses leading to activation or tolerance, and regulation of cell survival. Importantly for the clinician, accelerated rates of discovery in the field of glycoimmunology are being translated into innovative medical approaches that harness the interaction of glycans and GBPs to the benefit of the host and might soon lead to novel diagnostics and therapeutics.
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Affiliation(s)
- Bruce S Bochner
- Department of Medicine, Division of Allergy-Immunology, Northwestern University Feinberg School of Medicine, Chicago, Ill.
| | - Nives Zimmermann
- Department of Pediatrics, Division of Allergy and Immunology, Children's Hospital Medical Center, and Department of Pathology, University of Cincinnati College of Medicine, Cincinnati, Ohio
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83
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High-Throughput Synthesis of Diverse Compound Collections for Lead Discovery and Optimization. Handb Exp Pharmacol 2015; 232:73-89. [PMID: 26330259 DOI: 10.1007/164_2015_25] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Small-molecule intervention of protein function is one central dogma of drug discovery. The generation of small-molecule libraries fuels the discovery pipeline at many stages and thereby resembles a key aspect of this endeavor. High-throughput synthesis is a major source for compound libraries utilized in academia and industry, seeking new chemical modulators of pharmacological targets. Here, we discuss the crucial factors of library design strategies from the perspective of synthetic chemistry, giving a brief historic background and a summary of current approaches. Simple measures of success of a high-throughput synthesis such as quantity or diversity have long been discarded and replaced by more integrated measures. Case studies are presented and put into context to highlight the cross-connectivity of the various stages of the drug discovery process.
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84
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Podhorecka M, Markowicz J, Szymczyk A, Pawlowski J. Target Therapy in Hematological Malignances: New Monoclonal Antibodies. INTERNATIONAL SCHOLARLY RESEARCH NOTICES 2014; 2014:701493. [PMID: 27433507 PMCID: PMC4897146 DOI: 10.1155/2014/701493] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Revised: 09/22/2014] [Accepted: 09/23/2014] [Indexed: 11/17/2022]
Abstract
Apart from radio- and chemotherapy, monoclonal antibodies (MoAbs) represent a new, more selective tool in the treatment of hematological malignancies. MoAbs bind with the specific antigens of the tumors. This interaction is a basis for targeted therapies which exhibit few side effects and significant antitumor activity. This review provides an overview of the functional characteristics of MoAbs, with some examples of their clinical application. The promising results in the treatment of hematological malignancies have led to the more frequent usage of MoAbs in the therapy. Development of MoAbs is a subject of extensive research. They are a promising method of cancer treatment in the future.
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Affiliation(s)
- Monika Podhorecka
- Department of Hematooncology and Bone Marrow Transplantation, Medical University of Lublin, Staszica 11, 20-081 Lublin, Poland
| | - Justyna Markowicz
- Students Scientific Association at the Department of Hematooncology and Bone Marrow Transplantation, Medical University of Lublin, Lublin, Poland
| | - Agnieszka Szymczyk
- Department of Hematooncology and Bone Marrow Transplantation, Medical University of Lublin, Staszica 11, 20-081 Lublin, Poland
| | - Johannes Pawlowski
- Students Scientific Association at the Department of Hematooncology and Bone Marrow Transplantation, Medical University of Lublin, Lublin, Poland
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85
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Macauley MS, Crocker PR, Paulson JC. Siglec-mediated regulation of immune cell function in disease. Nat Rev Immunol 2014; 14:653-66. [PMID: 25234143 DOI: 10.1038/nri3737] [Citation(s) in RCA: 741] [Impact Index Per Article: 74.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
All mammalian cells display a diverse array of glycan structures that differ from those that are found on microbial pathogens. Siglecs are a family of sialic acid-binding immunoglobulin-like receptors that participate in the discrimination between self and non-self, and that regulate the function of cells in the innate and adaptive immune systems through the recognition of their glycan ligands. In this Review, we describe the recent advances in our understanding of the roles of Siglecs in the regulation of immune cell function in infectious diseases, inflammation, neurodegeneration, autoimmune diseases and cancer.
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Affiliation(s)
- Matthew S Macauley
- Departments of Cell and Molecular Biology, Immunology and Microbial Science, and Physiological Chemistry, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Paul R Crocker
- Division of Cell Signalling and Immunology, Wellcome Trust Building, College of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - James C Paulson
- Departments of Cell and Molecular Biology, Immunology and Microbial Science, and Physiological Chemistry, The Scripps Research Institute, La Jolla, California 92037, USA
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86
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Kawasaki N, Rillahan CD, Cheng TY, Van Rhijn I, Macauley MS, Moody DB, Paulson JC. Targeted delivery of mycobacterial antigens to human dendritic cells via Siglec-7 induces robust T cell activation. THE JOURNAL OF IMMUNOLOGY 2014; 193:1560-6. [PMID: 25000981 DOI: 10.4049/jimmunol.1303278] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Lipids from mycobacteria can be presented to human T cells by group 1 CD1 Ag-presenting molecules (CD1a, CD1b, and CD1c). Group 1 CD1-restricted T cells are activated by lipid Ags presented by myeloid dendritic cells (DCs), after which they generate antibacterial effector functions, including IFN-γ secretion and cytolysis. Thus, mycobacterial lipids are being investigated as components of novel vaccines for mycobacterial infections. In this study we show that the mycobacterial lipid Ag C80 glucose-6-monomycolate can be delivered to human CD1b(+) DCs via targeted liposomal nanoparticles, leading to robust group 1 CD1-restricted activation of T cells. Targeting was achieved by decorating the liposomes with a high-affinity glycan ligand of sialic acid-binding Ig-like lectin (Siglec)-7, a siglec receptor expressed on DCs that mediates rapid endocytosis and transport of its cargo to lysosomes. An Ab to Siglec-7 completely blocked the binding of targeted liposomes to human monocyte-derived DCs (Mo-DCs), demonstrating their targeting specificity. Mo-DCs pulsed with targeted liposomes containing C80 glucose-6-monomycolate more potently activated a CD1b-restricted T cell line relative to Mo-DCs pulsed with free lipid Ag or antigenic liposomes without Siglec-7 ligand. These data suggest that the endocytic function of Siglec-7 can be exploited to deliver glycolipid Ags to their target cell and increase the efficiency of display to T cells.
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Affiliation(s)
- Norihito Kawasaki
- Department of Cell and Molecular Biology, The Scripps Research Institute, La Jolla, CA 92037; Department of Chemical Physiology, The Scripps Research Institute, La Jolla, CA 92037; Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037
| | - Cory D Rillahan
- Department of Cell and Molecular Biology, The Scripps Research Institute, La Jolla, CA 92037; Department of Chemical Physiology, The Scripps Research Institute, La Jolla, CA 92037; Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037
| | - Tan-Yun Cheng
- Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115; and
| | - Ildiko Van Rhijn
- Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115; and Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, 3584 CL Utrecht, The Netherlands
| | - Matthew S Macauley
- Department of Cell and Molecular Biology, The Scripps Research Institute, La Jolla, CA 92037; Department of Chemical Physiology, The Scripps Research Institute, La Jolla, CA 92037; Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037
| | - D Branch Moody
- Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115; and
| | - James C Paulson
- Department of Cell and Molecular Biology, The Scripps Research Institute, La Jolla, CA 92037; Department of Chemical Physiology, The Scripps Research Institute, La Jolla, CA 92037; Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037;
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87
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Chen GY, Brown NK, Zheng P, Liu Y. Siglec-G/10 in self-nonself discrimination of innate and adaptive immunity. Glycobiology 2014; 24:800-6. [PMID: 24996822 DOI: 10.1093/glycob/cwu068] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Siglec-G/10 is broadly expressed on B cells, dendritic cells and macrophage subsets. It binds strongly to CD24, a small glycosyl-phosphatidylinositol-anchored sialoprotein, in a sialylation-dependent manner. Targeted mutation of Siglecg dramatically elevates the level of natural IgM antibodies and its producer, B1 B cells. Incorporation of Siglec-G ligands to both T-dependent and T-independent immunogens reduces antibody production and induces B-cell tolerance to subsequent antigen challenges. By interacting with CD24, Siglec-G suppresses inflammatory responses to danger (damage)-associated molecular patterns, such as heat-shock proteins and high mobility group protein 1, but not to Toll-like receptor ligands. By a CD24-independent mechanism, Siglec-G has been shown to associate with Cbl to cause degradation of retinoic acid-inducible gene 1 and reduce production of type I interferon in response to RNA virus infection. The negative regulation by Siglec-G/10 may provide a mechanism for the host to discriminate between infectious nonself and noninfectious self, as envisioned by the late Dr. Charles A. Janeway.
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Affiliation(s)
- Guo-Yun Chen
- Center for Cancer and Immunology Research, Children's National Medical Center, 111 Michigan Avenue, NW, Washington, DC 20010, USA Department of Pediatrics, School of Medicine and Health Sciences, George Washington University
| | - Nicholas K Brown
- Center for Cancer and Immunology Research, Children's National Medical Center, 111 Michigan Avenue, NW, Washington, DC 20010, USA
| | - Pan Zheng
- Center for Cancer and Immunology Research, Children's National Medical Center, 111 Michigan Avenue, NW, Washington, DC 20010, USA Division of Pathology, Children's National Medical Center, Washington, DC 20010, USA
| | - Yang Liu
- Center for Cancer and Immunology Research, Children's National Medical Center, 111 Michigan Avenue, NW, Washington, DC 20010, USA
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88
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Jandus C, Boligan KF, Chijioke O, Liu H, Dahlhaus M, Démoulins T, Schneider C, Wehrli M, Hunger RE, Baerlocher GM, Simon HU, Romero P, Münz C, von Gunten S. Interactions between Siglec-7/9 receptors and ligands influence NK cell-dependent tumor immunosurveillance. J Clin Invest 2014; 124:1810-20. [PMID: 24569453 DOI: 10.1172/jci65899] [Citation(s) in RCA: 303] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Accepted: 12/19/2013] [Indexed: 12/15/2022] Open
Abstract
Alteration of the surface glycosylation pattern on malignant cells potentially affects tumor immunity by directly influencing interactions with glycan-binding proteins (lectins) on the surface of immunomodulatory cells. The sialic acid-binding Ig-like lectins Siglec-7 and -9 are MHC class I-independent inhibitory receptors on human NK cells that recognize sialic acid-containing carbohydrates. Here, we found that the presence of Siglec-9 defined a subset of cytotoxic NK cells with a mature phenotype and enhanced chemotactic potential. Interestingly, this Siglec-9+ NK cell population was reduced in the peripheral blood of cancer patients. Broad analysis of primary tumor samples revealed that ligands of Siglec-7 and -9 were expressed on human cancer cells of different histological types. Expression of Siglec-7 and -9 ligands was associated with susceptibility of NK cell-sensitive tumor cells and, unexpectedly, of presumably NK cell-resistant tumor cells to NK cell-mediated cytotoxicity. Together, these observations have direct implications for NK cell-based therapies and highlight the requirement to consider both MHC class I haplotype and tumor-specific glycosylation.
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MESH Headings
- Animals
- Antigens, CD/metabolism
- Antigens, Differentiation, Myelomonocytic/metabolism
- Antigens, Tumor-Associated, Carbohydrate/metabolism
- Cell Line, Tumor
- Cytotoxicity, Immunologic
- Female
- Glycosylation
- HeLa Cells
- Humans
- Immunity, Innate
- K562 Cells
- Killer Cells, Natural/classification
- Killer Cells, Natural/immunology
- Lectins/metabolism
- Ligands
- Male
- Mice
- Mice, Inbred NOD
- Mice, SCID
- Monitoring, Immunologic
- Neoplasms/immunology
- Sialic Acid Binding Immunoglobulin-like Lectins/metabolism
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89
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Häuselmann I, Borsig L. Altered tumor-cell glycosylation promotes metastasis. Front Oncol 2014; 4:28. [PMID: 24592356 PMCID: PMC3923139 DOI: 10.3389/fonc.2014.00028] [Citation(s) in RCA: 252] [Impact Index Per Article: 25.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Accepted: 01/29/2014] [Indexed: 12/14/2022] Open
Abstract
Malignant transformation of cells is associated with aberrant glycosylation presented on the cell-surface. Commonly observed changes in glycan structures during malignancy encompass aberrant expression and glycosylation of mucins; abnormal branching of N-glycans; and increased presence of sialic acid on proteins and glycolipids. Accumulating evidence supports the notion that the presence of certain glycan structures correlates with cancer progression by affecting tumor-cell invasiveness, ability to disseminate through the blood circulation and to metastasize in distant organs. During metastasis tumor-cell-derived glycans enable binding to cells in their microenvironment including endothelium and blood constituents through glycan-binding receptors – lectins. In this review, we will discuss current concepts how tumor-cell-derived glycans contribute to metastasis with the focus on three types of lectins: siglecs, galectins, and selectins. Siglecs are present on virtually all hematopoietic cells and usually negatively regulate immune responses. Galectins are mostly expressed by tumor cells and support tumor-cell survival. Selectins are vascular adhesion receptors that promote tumor-cell dissemination. All lectins facilitate interactions within the tumor microenvironment and thereby promote cancer progression. The identification of mechanisms how tumor glycans contribute to metastasis may help to improve diagnosis, prognosis, and aid to develop clinical strategies to prevent metastasis.
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Affiliation(s)
- Irina Häuselmann
- Zürich Center for Integrative Human Physiology, Institute of Physiology, University of Zürich , Zürich , Switzerland
| | - Lubor Borsig
- Zürich Center for Integrative Human Physiology, Institute of Physiology, University of Zürich , Zürich , Switzerland
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90
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Stuible M, Moraitis A, Fortin A, Saragosa S, Kalbakji A, Filion M, Tremblay GB. Mechanism and function of monoclonal antibodies targeting siglec-15 for therapeutic inhibition of osteoclastic bone resorption. J Biol Chem 2014; 289:6498-6512. [PMID: 24446437 DOI: 10.1074/jbc.m113.494542] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The use of monoclonal antibodies to target functionally important cell-surface proteins on bone-resorbing osteoclasts represents a promising approach for treatment of cancer-associated bone loss and other skeletal pathologies. Previously, we identified Siglec-15, a little studied sialic acid-binding receptor, as a candidate target that is highly up-regulated during osteoclast differentiation induced by the cytokine receptor activator of NF-κB ligand (RANKL). In this report, we confirm that Siglec-15 is localized to the plasma membrane where it can be targeted by monoclonal antibodies to inhibit differentiation of functional osteoclasts in vitro. Furthermore, we found that treatment of mice with these antibodies led to a marked increase in bone mineral density, consistent with inhibition of osteoclast activity. Interestingly, osteoblast numbers were maintained despite the anti-resorptive activity. At the molecular level, Siglec-15 interacts with the adapter protein DAP12 and can induce Akt activation when clustered on the osteoclast cell surface, which likely represents its normal signaling function. Importantly, we discovered that monoclonal antibodies induce rapid internalization, lysosomal targeting, and degradation of Siglec-15 by inducing receptor dimerization. This study defines a key regulatory node that controls osteoclast differentiation and activity downstream of RANKL and supports further development of Siglec-15 antibodies as a novel class of bone loss therapeutics.
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Affiliation(s)
- Matthew Stuible
- From Alethia Biotherapeutics Inc., Montréal, Québec H2X 1Y4, Canada
| | - Anna Moraitis
- From Alethia Biotherapeutics Inc., Montréal, Québec H2X 1Y4, Canada
| | - Annie Fortin
- From Alethia Biotherapeutics Inc., Montréal, Québec H2X 1Y4, Canada
| | - Stefan Saragosa
- From Alethia Biotherapeutics Inc., Montréal, Québec H2X 1Y4, Canada
| | - Aida Kalbakji
- From Alethia Biotherapeutics Inc., Montréal, Québec H2X 1Y4, Canada
| | - Mario Filion
- From Alethia Biotherapeutics Inc., Montréal, Québec H2X 1Y4, Canada
| | - Gilles B Tremblay
- From Alethia Biotherapeutics Inc., Montréal, Québec H2X 1Y4, Canada.
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91
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Hudak JE, Bertozzi CR. Glycotherapy: new advances inspire a reemergence of glycans in medicine. CHEMISTRY & BIOLOGY 2014; 21:16-37. [PMID: 24269151 PMCID: PMC4111574 DOI: 10.1016/j.chembiol.2013.09.010] [Citation(s) in RCA: 169] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2013] [Revised: 09/16/2013] [Accepted: 09/30/2013] [Indexed: 12/21/2022]
Abstract
The beginning of the 20(th) century marked the dawn of modern medicine with glycan-based therapies at the forefront. However, glycans quickly became overshadowed as DNA- and protein-focused treatments became readily accessible. The recent development of new tools and techniques to study and produce structurally defined carbohydrates has spurred renewed interest in the therapeutic applications of glycans. This review focuses on advances within the past decade that are bringing glycan-based treatments back to the forefront of medicine and the technologies that are driving these efforts. These include the use of glycans themselves as therapeutic molecules as well as engineering protein and cell surface glycans to suit clinical applications. Glycan therapeutics offer a rich and promising frontier for developments in the academic, biopharmaceutical, and medical fields.
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Affiliation(s)
- Jason E Hudak
- Department of Chemistry, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Carolyn R Bertozzi
- Department of Chemistry, University of California, Berkeley, Berkeley, CA 94720, USA; Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA; Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA 94720, USA.
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92
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Yang M, Jiang G, Li W, Qiu K, Zhang M, Carter CM, Al-Quran SZ, Li Y. Developing aptamer probes for acute myelogenous leukemia detection and surface protein biomarker discovery. J Hematol Oncol 2014; 7:5. [PMID: 24405684 PMCID: PMC3895837 DOI: 10.1186/1756-8722-7-5] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2013] [Accepted: 12/24/2013] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND The majority of patients with acute myelogenous leukemia (AML) still die of their disease. In order to improve survival rates in AML patients, new strategies are necessary to discover biomarkers for the detection and targeted therapy of AML. One of the advantages of the aptamer-based technology is the unique cell-based selection process, which allows us to efficiently select for cell-specific aptamers without knowing which target molecules are present on the cell surface. METHODS The NB4 AML cell line was used as the target cell population for selecting single stranded DNA aptamers. After determining the affinity of selected aptamers to leukocytes, the aptamers were used to phenotype human bone marrow leukocytes and AML cells in clinical specimens. Then a biotin-labelled aptamer was used to enrich and identify its target surface protein. RESULTS Three new aptamers were characterized from the selected aptamer pools (JH6, JH19, and K19). All of them can selectively recognize myeloid cells with Kd in the low nanomole range (2.77 to 12.37 nM). The target of the biotin-labelled K19 aptamer probe was identified as Siglec-5, a surface membrane protein in low abundance whose expression can serve as a biomarker of granulocytic maturation and be used to phenotype AML. More importantly, Siglec-5 expression can be used to detect low concentrations of AML cells in human bone marrow specimens, and functions as a potential target for leukemic therapy. CONCLUSIONS We have demonstrated a pipeline approach for developing single stranded DNA aptamer probes, phenotyping AML cells in clinical specimens, and then identifying the aptamer-recognized target protein. The developed aptamer probes and identified Siglec-5 protein may potentially be used for leukemic cell detection and therapy in our future clinical practice.
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MESH Headings
- Acute Disease
- Antigens, CD/genetics
- Antigens, CD/metabolism
- Antigens, Differentiation, Myelomonocytic/genetics
- Antigens, Differentiation, Myelomonocytic/metabolism
- Aptamers, Nucleotide/genetics
- Aptamers, Nucleotide/metabolism
- Biomarkers, Tumor/genetics
- Biomarkers, Tumor/metabolism
- Cell Line, Tumor
- DNA, Single-Stranded/genetics
- DNA, Single-Stranded/metabolism
- Diagnosis, Differential
- Flow Cytometry
- HL-60 Cells
- Humans
- Lectins/genetics
- Lectins/metabolism
- Leukemia, Myeloid/diagnosis
- Leukemia, Myeloid/genetics
- Leukemia, Myeloid/pathology
- Leukemia, Promyelocytic, Acute/diagnosis
- Leukemia, Promyelocytic, Acute/genetics
- Leukemia, Promyelocytic, Acute/pathology
- Leukocytes/metabolism
- Membrane Proteins/genetics
- Membrane Proteins/metabolism
- Polymerase Chain Reaction
- Protein Binding
- Reproducibility of Results
- SELEX Aptamer Technique/methods
- Sensitivity and Specificity
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Affiliation(s)
- Mingli Yang
- UF/Shands Medical Laboratory at Rocky Point, 4800 35th Drive, Gainesville, FL 32608, USA
| | - Guohua Jiang
- UF/Shands Medical Laboratory at Rocky Point, 4800 35th Drive, Gainesville, FL 32608, USA
| | - Wenjing Li
- UF/Shands Medical Laboratory at Rocky Point, 4800 35th Drive, Gainesville, FL 32608, USA
| | - Kai Qiu
- UF/Shands Medical Laboratory at Rocky Point, 4800 35th Drive, Gainesville, FL 32608, USA
| | - Min Zhang
- UF/Shands Medical Laboratory at Rocky Point, 4800 35th Drive, Gainesville, FL 32608, USA
| | - Christopher M Carter
- UF/Shands Medical Laboratory at Rocky Point, 4800 35th Drive, Gainesville, FL 32608, USA
| | - Samer Z Al-Quran
- UF/Shands Medical Laboratory at Rocky Point, 4800 35th Drive, Gainesville, FL 32608, USA
| | - Ying Li
- UF/Shands Medical Laboratory at Rocky Point, 4800 35th Drive, Gainesville, FL 32608, USA
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93
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Rillahan CD, Macauley MS, Schwartz E, He Y, McBride R, Arlian BM, Rangarajan J, Fokin VV, Paulson JC. Disubstituted Sialic Acid Ligands Targeting Siglecs CD33 and CD22 Associated with Myeloid Leukaemias and B Cell Lymphomas. Chem Sci 2014; 5:2398-2406. [PMID: 24921038 DOI: 10.1039/c4sc00451e] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The siglec family of sialic acid-binding proteins are endocytic immune cell receptors that are recognized as potential targets for cell directed therapies. CD33 and CD22 are prototypical members and are validated candidates for targeting acute myeloid leukaemia and non-Hodgkin's lymphomas due to their restricted expression on myeloid cells and B-cells, respectively. While nanoparticles decorated with high affinity siglec ligands represent an attractive platform for delivery of therapeutic agents to these cells, a lack of ligands with suitable affinity and/or selectivity has hampered progress. Herein we describe selective ligands for both of these siglecs, which when displayed on liposomal nanoparticles, can efficiently target the cells expressing them in peripheral human blood. Key to their identification was the development of a facile method for chemo-enzymatic synthesis of disubstituted sialic acid analogues, combined with iterative rounds of synthesis and rapid functional analysis using glycan microarrays.
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Affiliation(s)
- Cory D Rillahan
- Department of Cell and Molecular Biology, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA 92037 (USA) ; Department of Chemical Physiology, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA 92037 (USA)
| | - Matthew S Macauley
- Department of Cell and Molecular Biology, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA 92037 (USA) ; Department of Chemical Physiology, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA 92037 (USA)
| | - Erik Schwartz
- Department of Chemistry, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA 92037 (USA)
| | - Yuan He
- Department of Cell and Molecular Biology, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA 92037 (USA) ; Department of Chemical Physiology, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA 92037 (USA)
| | - Ryan McBride
- Department of Cell and Molecular Biology, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA 92037 (USA) ; Department of Chemical Physiology, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA 92037 (USA)
| | - Britni M Arlian
- Department of Cell and Molecular Biology, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA 92037 (USA) ; Department of Chemical Physiology, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA 92037 (USA)
| | - Janani Rangarajan
- Department of Cell and Molecular Biology, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA 92037 (USA) ; Department of Chemical Physiology, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA 92037 (USA)
| | - Valery V Fokin
- Department of Chemistry, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA 92037 (USA)
| | - James C Paulson
- Department of Cell and Molecular Biology, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA 92037 (USA) ; Department of Chemical Physiology, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA 92037 (USA)
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94
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Liu P, Wang X, Itano MS, Neumann AK, de Silva AM, Jacobson K, Thompson NL. Low copy numbers of DC-SIGN in cell membrane microdomains: implications for structure and function. Traffic 2013; 15:179-96. [PMID: 24313910 DOI: 10.1111/tra.12138] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2013] [Revised: 11/07/2013] [Accepted: 11/11/2013] [Indexed: 12/17/2022]
Abstract
Presently, there are few estimates of the number of molecules occupying membrane domains. Using a total internal reflection fluorescence microscopy (TIRFM) imaging approach, based on comparing the intensities of fluorescently labeled microdomains with those of single fluorophores, we measured the occupancy of DC-SIGN, a C-type lectin, in membrane microdomains. DC-SIGN or its mutants were labeled with primary monoclonal antibodies (mAbs) in either dendritic cells (DCs) or NIH3T3 cells, or expressed as GFP fusions in NIH3T3 cells. The number of DC-SIGN molecules per microdomain ranges from only a few to over 20, while microdomain dimensions range from the diffraction limit to > 1 µm. The largest fraction of microdomains, appearing at the diffraction limit, in either immature DCs or 3 T3 cells contains only 4-8 molecules of DC-SIGN, consistent with our preliminary super-resolution Blink microscopy estimates. We further show that these small assemblies are sufficient to bind and efficiently internalize a small (∼ 50 nm) pathogen, dengue virus, leading to infection of host cells.
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Affiliation(s)
- Ping Liu
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599-7090, USA
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95
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Khatua B, Roy S, Mandal C. Sialic acids siglec interaction: a unique strategy to circumvent innate immune response by pathogens. Indian J Med Res 2013; 138:648-62. [PMID: 24434319 PMCID: PMC3928697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
Abstract
Sialic acids (Sias) are nine-carbon keto sugars primarily present on the terminal residue of cell surface glycans. Sialic acid binding immunoglobulins (Ig)-like lectins (siglecs) are generally expressed on various immune cells. They selectively recognize different linkage-specific sialic acids and undertake a variety of cellular functions. Many pathogens either synthesize or acquire sialic acids from the host. Sialylated pathogens generally use siglecs to manipulate the host immune response. The present review mainly deals with the newly developed information regarding mechanism of acquisition of sialic acids by pathogens and their biological relevance especially in the establishment of successful infection by impairing host innate immunity. The pathogens which are unable to synthesize sialic acids might adsorb these from the host as a way to engage the inhibitory siglecs. They promote association with the immune cells through sialic acids-siglec dependent manner. Such an association plays an important role to subvert host's immunity. Detailed investigation of these pathways has been discussed in this review. Particular attention has been focused on Pseudomonas aeruginosa (PA) and Leishmania donovani.
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Affiliation(s)
- Biswajit Khatua
- Cancer Biology & Inflammatory Disorder Division, CSIR-Indian Institute of Chemical Biology, Kolkata, India
| | - Saptarshi Roy
- Cancer Biology & Inflammatory Disorder Division, CSIR-Indian Institute of Chemical Biology, Kolkata, India
| | - Chitra Mandal
- Cancer Biology & Inflammatory Disorder Division, CSIR-Indian Institute of Chemical Biology, Kolkata, India,Reprint requests: Dr Chitra Mandal, Cancer Biology & Inflammatory Disorders Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S.C. Mullick Road, Kolkata 700 032, India e-mail: or
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96
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Abstract
The lymphatic system has a critical role in the immune system’s recognition and response to disease, and it is an additional circulatory system throughout the entire body. Most solid cancers primarily spread from the main site via the tumour’s surrounding lymphatics before haematological dissemination. Targeting drugs to lymphatic system is quite complicated because of its intricate physiology. Therefore, it tends to be an important target for developing novel therapeutics. Currently, nanocarriers have encouraged the lymphatic targeting, but still there are challenges of locating drugs and bioactives to specific sites, maintaining desired action and crossing all the physiological barriers. Lymphatic therapy using drug-encapsulated colloidal carriers especially liposomes and solid lipid nanoparticles emerges as a new technology to provide better penetration into the lymphatics where residual disease exists. Optimising the proper procedure, selecting the proper delivery route and target area and making use of surface engineering tool, better carrier for lymphotropic system can be achieved. Thus, new methods of delivering drugs and other carriers to lymph nodes are currently under investigation.
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Affiliation(s)
- Abraham J. Domb
- School of Pharmacy-Faculty of Medicine The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Wahid Khan
- Department of Pharmaceutics, National Institute of Pharmaceutical Education & Research (NIPER), Balanagar, Hyderabad, Andhra Pradesh India
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97
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Pfrengle F, Macauley MS, Kawasaki N, Paulson JC. Copresentation of antigen and ligands of Siglec-G induces B cell tolerance independent of CD22. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2013; 191:1724-31. [PMID: 23836061 PMCID: PMC3735655 DOI: 10.4049/jimmunol.1300921] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Differentiation of self from nonself is indispensable for maintaining B cell tolerance in peripheral tissues. CD22 and Siglec-G (sialic acid-binding Ig-like lectin G) are two inhibitory coreceptors of the BCR that are implicated in maintenance of tolerance to self Ags. Enforced ligation of CD22 and the BCR by a nanoparticle displaying both Ag and CD22 ligands induces a tolerogenic circuit resulting in apoptosis of the Ag-reactive B cell. Whether Siglec-G also has this property has not been investigated in large part owing to the lack of a selective Siglec-G ligand. In this article, we report the development of a selective high-affinity ligand for Siglec-G and its application as a chemical tool to investigate the tolerogenic potential of Siglec-G. We find that liposomal nanoparticles decorated with Ag and Siglec-G ligand inhibit BCR signaling in both B1 and B2 B cells compared with liposomes displaying Ag alone. Not only is inhibition of B cell activation observed by ligating the BCR with Siglec-G, but robust tolerance toward T-independent and T-dependent Ags is also induced in mice. The ability of Siglec-G to inhibit B cell activation equally in both B1 and B2 subsets is consistent with our observation that Siglec-G is expressed at a relatively constant level throughout numerous B cell subsets. These results suggest that Siglec-G may contribute to maintenance of B cell tolerance toward self Ags in various B cell compartments.
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MESH Headings
- Animals
- Antibodies, Monoclonal/immunology
- B-Lymphocyte Subsets/immunology
- Calcium Signaling
- Dendritic Cells/immunology
- Gene Expression Regulation
- Germinal Center/cytology
- Immune Tolerance/immunology
- Immunologic Memory
- Lectins/biosynthesis
- Lectins/genetics
- Lectins/immunology
- Ligands
- Liposomes
- Lymphopoiesis
- Mice
- Mice, Inbred C57BL
- Mice, Mutant Strains
- Mice, Transgenic
- Organ Specificity
- Protein Tyrosine Phosphatase, Non-Receptor Type 6/immunology
- Receptors, Antigen, B-Cell/biosynthesis
- Receptors, Antigen, B-Cell/genetics
- Receptors, Antigen, B-Cell/immunology
- Sialic Acid Binding Ig-like Lectin 2/immunology
- Sialic Acid Binding Immunoglobulin-like Lectins
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Affiliation(s)
- Fabian Pfrengle
- Department of Chemical Physiology, The Scripps Research Institute, La Jolla, CA 92037 (USA)
| | - Matthew S. Macauley
- Department of Chemical Physiology, The Scripps Research Institute, La Jolla, CA 92037 (USA)
| | - Norihito Kawasaki
- Department of Chemical Physiology, The Scripps Research Institute, La Jolla, CA 92037 (USA)
| | - James C. Paulson
- Department of Chemical Physiology, The Scripps Research Institute, La Jolla, CA 92037 (USA)
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98
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Kano G, Almanan M, Bochner BS, Zimmermann N. Mechanism of Siglec-8-mediated cell death in IL-5-activated eosinophils: role for reactive oxygen species-enhanced MEK/ERK activation. J Allergy Clin Immunol 2013; 132:437-45. [PMID: 23684072 PMCID: PMC4042061 DOI: 10.1016/j.jaci.2013.03.024] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Revised: 03/11/2013] [Accepted: 03/19/2013] [Indexed: 01/10/2023]
Abstract
BACKGROUND Sialic acid-binding immunoglobulin-like lectin (Siglec)-8 is expressed on human eosinophils, where its ligation induces cell death. Paradoxically, Siglec-8-mediated cell death is markedly enhanced by the presence of the activation and survival factor IL-5 and becomes independent of caspase activity. OBJECTIVE In this report we investigate the mechanism of Siglec-8-mediated cell death in activated eosinophils. METHODS Human peripheral blood eosinophils were treated with agonistic anti-Siglec-8 antibody and IL-5, and cell death was determined by using flow cytometry and morphology. Phosphorylation of mitogen-activated protein kinase (MAPK) was determined by using phosphoLuminex, flow cytometry, and Western blotting. Reactive oxygen species (ROS) accumulation was determined by using dihydrorhodamine fluorescence. RESULTS Costimulation with anti-Siglec-8 and IL-5 significantly increased the rate and proportion of cell death by means of necrosis accompanied by granule release compared with that seen after stimulation with anti-Siglec-8 alone, in which apoptosis predominated. Together with the caspase-independent mode of cell death in costimulated cells, these findings suggest the activation of a specific and distinct biochemical pathway of cell death during anti-Siglec-8/IL-5 costimulation. Phosphorylation of extracellular signal-regulated kinase (ERK) 1/2 and MAPK-ERK kinase (MEK) 1 was significantly enhanced and sustained in costimulated cells compared with that seen in cells stimulated with IL-5 alone; anti-Siglec-8 alone did not cause ERK1/2 phosphorylation. MEK1 inhibitors blocked anti-Siglec-8/IL-5-induced cell death. ROS accumulation was induced by Siglec-8 ligation in a MEK-independent manner. In contrast, an ROS inhibitor prevented the anti-Siglec-8/IL-5-induced enhancement of ERK phosphorylation and cell death. Exogenous ROS mimicked stimulation by anti-Siglec-8 and was sufficient to induce enhanced cell death in IL-5-treated cells. Collectively, these data suggest that the enhancement of ERK phosphorylation is downstream of ROS generation. CONCLUSIONS In activated eosinophils ligation of Siglec-8 leads to ROS-dependent enhancement of IL-5-induced ERK phosphorylation, which results in a novel mode of biochemically regulated eosinophil cell death.
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Affiliation(s)
- Gen Kano
- Division of Allergy & Immunology, Cincinnati Children’s Hospital, and Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Maha Almanan
- Division of Allergy & Immunology, Cincinnati Children’s Hospital, and Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Bruce S. Bochner
- Department of Medicine, Division of Allergy and Clinical Immunology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Nives Zimmermann
- Division of Allergy & Immunology, Cincinnati Children’s Hospital, and Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
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99
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Rillahan CD, Schwartz E, Rademacher C, McBride R, Rangarajan J, Fokin VV, Paulson JC. On-chip synthesis and screening of a sialoside library yields a high affinity ligand for Siglec-7. ACS Chem Biol 2013; 8:1417-22. [PMID: 23597400 DOI: 10.1021/cb400125w] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The Siglec family of sialic acid-binding proteins are differentially expressed on white blood cells of the immune system and represent an attractive class of targets for cell-directed therapy. Nanoparticles decorated with high-affinity Siglec ligands show promise for delivering cargo to Siglec-bearing cells, but this approach has been limited by a lack of ligands with suitable affinity and selectivity. Building on previous work employing solution-phase sialoside library synthesis and subsequent microarray screening, we herein report a more streamlined 'on-chip' synthetic approach. By printing a small library of alkyne sialosides and subjecting these to 'on-chip' click reactions, the largest sialoside analogue library to date was generated. Siglec-screening identified a selective Siglec-7 ligand, which when displayed on liposomal nanoparticles, allows for targeting of Siglec-7(+) cells in peripheral human blood. In silico docking to the crystal structure of Siglec-7 provides a rationale for the affinity gains observed for this novel sialic acid analogue.
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Affiliation(s)
| | | | - Christoph Rademacher
- Department of Biomolecular Systems, Max Planck Institute of Colloids and Interfaces, Am
Mühlenberg 1, 14424 Potsdam, Germany
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100
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Griciuc A, Serrano-Pozo A, Parrado AR, Lesinski AN, Asselin CN, Mullin K, Hooli B, Choi SH, Hyman BT, Tanzi RE. Alzheimer's disease risk gene CD33 inhibits microglial uptake of amyloid beta. Neuron 2013; 78:631-43. [PMID: 23623698 DOI: 10.1016/j.neuron.2013.04.014] [Citation(s) in RCA: 742] [Impact Index Per Article: 67.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/09/2013] [Indexed: 10/26/2022]
Abstract
The transmembrane protein CD33 is a sialic acid-binding immunoglobulin-like lectin that regulates innate immunity but has no known functions in the brain. We have previously shown that the CD33 gene is a risk factor for Alzheimer's disease (AD). Here, we observed increased expression of CD33 in microglial cells in AD brain. The minor allele of the CD33 SNP rs3865444, which confers protection against AD, was associated with reductions in both CD33 expression and insoluble amyloid beta 42 (Aβ42) levels in AD brain. Furthermore, the numbers of CD33-immunoreactive microglia were positively correlated with insoluble Aβ42 levels and plaque burden in AD brain. CD33 inhibited uptake and clearance of Aβ42 in microglial cell cultures. Finally, brain levels of insoluble Aβ42 as well as amyloid plaque burden were markedly reduced in APP(Swe)/PS1(ΔE9)/CD33(-/-) mice. Therefore, CD33 inactivation mitigates Aβ pathology and CD33 inhibition could represent a novel therapy for AD.
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Affiliation(s)
- Ana Griciuc
- Genetics and Aging Research Unit, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
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