Fibronectin on the Surface of Myeloma Cell-derived Exosomes Mediates Exosome-Cell Interactions.
Purushothaman, Anurag; Bandari, Shyam Kumar; Liu, Jian; Mobley, James A; Brown, Elizabeth E; Sanderson, Ralph D
2016-01-22
Exosomes regulate cell behavior by binding to and delivering their cargo to target cells; however, the mechanisms mediating exosome-cell interactions are poorly understood. Heparan sulfates on target cell surfaces can act as receptors for exosome uptake, but the ligand for heparan sulfate on exosomes has not been identified. Using exosomes isolated from myeloma cell lines and from myeloma patients, we identify exosomal fibronectin as a key heparan sulfate-binding ligand and mediator of exosome-cell interactions. We discovered that heparan sulfate plays a dual role in exosome-cell interaction; heparan sulfate on exosomes captures fibronectin, and on target cells it acts as a receptor for fibronectin. Removal of heparan sulfate from the exosome surface releases fibronectin and dramatically inhibits exosome-target cell interaction. Antibody specific for the Hep-II heparin-binding domain of fibronectin blocks exosome interaction with tumor cells or with marrow stromal cells. Regarding exosome function, fibronectin-mediated binding of exosomes to myeloma cells activated p38 and pERK signaling and expression of downstream target genes DKK1 and MMP-9, two molecules that promote myeloma progression. Antibody against fibronectin inhibited the ability of myeloma-derived exosomes to stimulate endothelial cell invasion. Heparin or heparin mimetics including Roneparstat, a modified heparin in phase I trials in myeloma patients, significantly inhibited exosome-cell interactions. These studies provide the first evidence that fibronectin binding to heparan sulfate mediates exosome-cell interactions, revealing a fundamental mechanism important for exosome-mediated cross-talk within tumor microenvironments. Moreover, these results imply that therapeutic disruption of fibronectin-heparan sulfate interactions will negatively impact myeloma tumor growth and progression. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.
Fibronectin on the Surface of Myeloma Cell-derived Exosomes Mediates Exosome-Cell Interactions*
Purushothaman, Anurag; Bandari, Shyam Kumar; Liu, Jian; Mobley, James A.; Brown, Elizabeth E.; Sanderson, Ralph D.
2016-01-01
Exosomes regulate cell behavior by binding to and delivering their cargo to target cells; however, the mechanisms mediating exosome-cell interactions are poorly understood. Heparan sulfates on target cell surfaces can act as receptors for exosome uptake, but the ligand for heparan sulfate on exosomes has not been identified. Using exosomes isolated from myeloma cell lines and from myeloma patients, we identify exosomal fibronectin as a key heparan sulfate-binding ligand and mediator of exosome-cell interactions. We discovered that heparan sulfate plays a dual role in exosome-cell interaction; heparan sulfate on exosomes captures fibronectin, and on target cells it acts as a receptor for fibronectin. Removal of heparan sulfate from the exosome surface releases fibronectin and dramatically inhibits exosome-target cell interaction. Antibody specific for the Hep-II heparin-binding domain of fibronectin blocks exosome interaction with tumor cells or with marrow stromal cells. Regarding exosome function, fibronectin-mediated binding of exosomes to myeloma cells activated p38 and pERK signaling and expression of downstream target genes DKK1 and MMP-9, two molecules that promote myeloma progression. Antibody against fibronectin inhibited the ability of myeloma-derived exosomes to stimulate endothelial cell invasion. Heparin or heparin mimetics including Roneparstat, a modified heparin in phase I trials in myeloma patients, significantly inhibited exosome-cell interactions. These studies provide the first evidence that fibronectin binding to heparan sulfate mediates exosome-cell interactions, revealing a fundamental mechanism important for exosome-mediated cross-talk within tumor microenvironments. Moreover, these results imply that therapeutic disruption of fibronectin-heparan sulfate interactions will negatively impact myeloma tumor growth and progression. PMID:26601950
Enterovirus 71 Uses Cell Surface Heparan Sulfate Glycosaminoglycan as an Attachment Receptor
Tan, Chee Wah; Poh, Chit Laa; Sam, I-Ching
2013-01-01
Enterovirus 71 (EV-71) infections are usually associated with mild hand, foot, and mouth disease in young children but have been reported to cause severe neurological complications with high mortality rates. To date, four EV-71 receptors have been identified, but inhibition of these receptors by antagonists did not completely abolish EV-71 infection, implying that there is an as yet undiscovered receptor(s). Since EV-71 has a wide range of tissue tropisms, we hypothesize that EV-71 infections may be facilitated by using receptors that are widely expressed in all cell types, such as heparan sulfate. In this study, heparin, polysulfated dextran sulfate, and suramin were found to significantly prevent EV-71 infection. Heparin inhibited infection by all the EV-71 strains tested, including those with a single-passage history. Neutralization of the cell surface anionic charge by polycationic poly-d-lysine and blockage of heparan sulfate by an anti-heparan sulfate peptide also inhibited EV-71 infection. Interference with heparan sulfate biosynthesis either by sodium chlorate treatment or through transient knockdown of N-deacetylase/N-sulfotransferase-1 and exostosin-1 expression reduced EV-71 infection in RD cells. Enzymatic removal of cell surface heparan sulfate by heparinase I/II/III inhibited EV-71 infection. Furthermore, the level of EV-71 attachment to CHO cell lines that are variably deficient in cell surface glycosaminoglycans was significantly lower than that to wild-type CHO cells. Direct binding of EV-71 particles to heparin-Sepharose columns under physiological salt conditions was demonstrated. We conclude that EV-71 infection requires initial binding to heparan sulfate as an attachment receptor. PMID:23097443
NASA Astrophysics Data System (ADS)
Hu, Yu-Peng; Lin, Shu-Yi; Huang, Cheng-Yen; Zulueta, Medel Manuel L.; Liu, Jing-Yuan; Chang, Wen; Hung, Shang-Cheng
2011-07-01
Cell surface carbohydrates play significant roles in a number of biologically important processes. Heparan sulfate, for instance, is a ubiquitously distributed polysulfated polysaccharide that is involved, among other things, in the initial step of herpes simplex virus type 1 (HSV-1) infection. The virus interacts with cell-surface heparan sulfate to facilitate host-cell attachment and entry. 3-O-Sulfonated heparan sulfate has been found to function as an HSV-1 entry receptor. Achieving a complete understanding of these interactions requires the chemical synthesis of such oligosaccharides, but this remains challenging. Here, we present a convenient approach for the synthesis of two irregular 3-O-sulfonated heparan sulfate octasaccharides, making use of a key disaccharide intermediate to acquire different building blocks for the oligosaccharide chain assembly. Despite substantial structural differences, the prepared 3-O-sulfonated sugars blocked viral infection in a dosage-dependent manner with remarkable similarity to one another.
Wu, Chunxiao; Wang, Shu
2012-01-01
Binding to heparan sulfate is essential for baculovirus transduction of mammalian cells. Our previous study shows that gp64, the major glycoprotein on the virus surface, binds to heparin in a pH-dependent way, with a stronger binding at pH 6.2 than at 7.4. Using fluorescently labeled peptides, we mapped the pH-dependent heparin-binding sequence of gp64 to a 22-amino-acid region between residues 271 and 292. Binding of this region to the cell surface was also pH dependent, and peptides containing this sequence could efficiently inhibit baculovirus transduction of mammalian cells at pH 6.2. When the heparin-binding peptide was immobilized onto the bead surface to mimic the high local concentration of gp64 on the virus surface, the peptide-coated magnetic beads could efficiently pull down cells expressing heparan sulfate but not cells pretreated with heparinase or cells not expressing heparan sulfate. Interestingly, although this heparin-binding function is essential for baculovirus transduction of mammalian cells, it is dispensable for infection of Sf9 insect cells. Virus infectivity on Sf9 cells was not reduced by the presence of heparin or the identified heparin-binding peptide, even though the peptide could bind to Sf9 cell surface and be efficiently internalized. Thus, our data suggest that, depending on the availability of the target molecules on the cell surface, baculoviruses can use two different methods, electrostatic interaction with heparan sulfate and more specific receptor binding, for cell attachment.
Snigireva, A V; Vrublevskaya, V V; Skarga, Y Y; Morenkov, O S
2016-01-01
Heat shock protein Hsp90, detected in the extracellular space and on the membrane of cells, plays an important role in cell motility, migration, invasion and metastasis of tumor cells. At present, the functional role and molecular mechanisms of Hsp90 binding to plasma membrane are not elucidated. Using isoform-specific antibodies against Hsp90, Hsp9α and Hsp90β, we showed that membrane-bound Hsp90α and Hsp90β play a significant role in migration of human fibrosarcoma (HT1080) and glioblastoma (A-172) cells in vitro. Disorders of sulfonation of cell heparan sulfates, cleavage of cell heparan. sulfates by heparinase I/III as well as treatment of cells with heparin lead to an abrupt reduction in the expression level of Hsp90 isoforms. Furthermore, heparin significantly inhibits tumor cell migration. The results obtained demonstrate that two isoforms of membrane-bound Hsp90 are involved in migration of tumor cells in vitro and that cell surface heparan sulfate proteoglycans play a pivotal role in the "anchoring" of Hsp90α and Hsp90β to the plasma membrane.
Hayashi, K; Hayashi, M; Jalkanen, M; Firestone, J H; Trelstad, R L; Bernfield, M
1987-10-01
The core protein of the proteoglycan at the cell surface of NMuMG mouse mammary epithelial cells bears both heparan and chondroitin sulfate chains and is recognized by the monoclonal antibody 281-2. Using this antibody and the peroxidase-antiperoxidase staining technique in adult mouse tissues, we found that the antibody recognizes the antigen in a highly restricted distribution, staining a variety of epithelial cells but no cells derived from embryonic mesoderm or neural crest. The antibody fails to stain any stromal (mesenchymal) or neuronal cells, with the exception of plasma cells and Leydig cells. Squamous and transitional epithelia stain intensely over their entire surfaces, whereas cuboidal and columnar epithelia stain moderately and only at the lateral surface of the basal cells. Within squamous and transitional epithelial tissues that undergo physiological regeneration (e.g., epidermis), the most superficial and differentiated cell types fail to stain. Within glandular and branched epithelia (e.g., pancreas), the secretory alveolar cells fail to stain. When evaluated by electron microscopy, granular deposits of stain are seen on the plasma membrane, especially on lateral surfaces, but none are noted within the cells or the basement membrane. These results indicate that in adult tissues the core protein of this heparan sulfate-rich proteoglycan is expressed almost exclusively at epithelial cell surfaces. Expression appears to be lost as the cells become either mature or highly differentiated.
Genetic epistasis between heparan sulfate and FGF-Ras signaling controls lens development
Qu, Xiuxia; Hertzler, Kristina; Pan, Yi; Grobe, Kay; Robinson, Michael L.; Zhang, Xin
2011-01-01
Vertebrate lens development depends on a complex network of signaling molecules to coordinate cell proliferation, migration and differentiation. In this study, we have studied the role of heparan sulfate in lens specific signaling by generating a conditional ablation of heparan sulfate modification genes, Ndst1 and Ndst2. In this mutant, N-sulfation of heparan sulfate was disrupted after the lens induction stage, resulting in reduced lens cell proliferation, increased cell death and defective lens fiber differentiation in later lens development. The loss of Ndst function also prevented the assembly of Fgf/Fgfr complexes on the lens cell surface and disrupted ERK signaling within the lens. We further demonstrated that Ndst mutation completely inhibited the FGF1 and Fgf3 overexpression phenotypes, but Kras reactivation was sufficient to reverse the Ndst deficient lens differentiation defect. The epistatic relationship between Ndst and FGF-Ras signaling demonstrates that FGF signaling is the predominant signaling pathway controlled by Ndst in lens development. PMID:21536023
Li, Xiulian; Lan, Ying; He, Yanli; Liu, Yong; Luo, Heng; Yu, Haibo; Song, Ni; Ren, Sumei; Liu, Tianwei; Hao, Cui; Guo, Yunliang; Zhang, Lijuan
2017-01-01
Bleomycin is a clinically used anti-cancer drug that produces DNA breaks once inside of cells. However, bleomycin is a positively charged molecule and cannot get inside of cells by free diffusion. We previously reported that the cell surface negatively charged glycosaminoglycans (GAGs) may be involved in the cellular uptake of bleomycin. We also observed that a class of positively charged small molecules has Golgi localization once inside of the cells. We therefore hypothesized that bleomycin might perturb Golgi-operated GAG biosynthesis. We used stable isotope labeling coupled with LC/MS analysis of GAG disaccharides simultaneously from bleomycin-treated and non-treated cancer cells. To further understand the cytotoxicity of bleomycin and its relationship to GAGs, we used sodium chlorate to inhibit GAG sulfation and commercially available GAGs to compete for cell surface GAG/bleomycin interactions in seven cell lines including CHO745 defective in both heparan sulfate and chondroitin sulfate biosynthesis. we discovered that heparan sulfate GAG was significantly undersulfated and the quantity and disaccharide compositions of GAGs were changed in bleomycin-treated cells in a concentration- and time-dependent manner. We revealed that bleomycin-induced cytotoxicity was directly related to cell surface GAGs. GAGs were targeted by bleomycin both at cell surface and at Golgi. Thus, GAGs might be the biological relevant molecules that might be related to the bleomycin-induced fibrosis in certain cancer patients, a severe side effect with largely unknown molecular mechanism. © 2017 The Author(s). Published by S. Karger AG, Basel.
Adeno-associated virus type 2 binding study on model heparan sulfate surface
NASA Astrophysics Data System (ADS)
Negishi, Atsuko; Liu, Jian; McCarty, Douglas; Samulski, Jude; Superfine, Richard
2003-11-01
Understanding the mechanisms involved in virus infections is useful in its application in areas such as gene therapy, drug development and delivery, and biosensors. In collaboration with UNC Gene Therapy Center and School of Pharmacy, we are specifically looking at the interaction between human parvovirus adeno-associated virus type 2 (AAV2), a potential viral vector, and heparan sulfate proteoglycan (HSPG), a known cell surface receptor for AAV2. Recent development in glycobiology has shown that some protein-polysaccharide binding is sugar sequence dependent. Heparan sulfate (HS) is a polysaccharide chain of sulfated iduronic/glucuronic and sulfate glucosamine residues and can be differentiated into sequence specific structures by enzymes. These enzymatic modifications, known as heparan sulfate sulfotransferase modified modifications, have been shown to change the biological nature of heparan sulfate such as specific binding to proteins and viruses. For understanding HS-assisted viral infection mechanisms, we are interested in investigating the binding affinity and stability of AAV to different HS structures. We have developed a model heparan sulfate surface in which AAV adsorption studies are done and analyzed using the atomic force microscope (AFM). In addition, a miniArray assay has been created to facilitate to this study. Adsorption studies are done in 4 white LED wells with approximately 3 mm2 reaction areas which minimize sample use and waste.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tiwari, Vaibhav; Department of Microbiology and Immunology, University of Illinois at Chicago, Chicago, IL 60612; Department of Basic Medical Sciences, College of Osteopathic Medicine of the Pacific and College of Optometry, Western University of Health Sciences, Pomona, CA 91766
2009-12-18
Human herpesvirus-8 (HHV-8) is known to interact with cell surface heparan sulfate (HS) for entry into a target cell. Here we investigated the role of HS during HHV-8 glycoproteins-induced cell fusion. Interestingly, the observed fusion demonstrated an unusual dependence on HS as evident from following lines of evidence: (1) a significant reduction in cell-to-cell fusion occurred when target cells were treated with heparinase; (2) in a competition assay, when the effector cells expressing HHV-8 glycoproteins were challenged with soluble HS, cell-to-cell fusion was reduced; and, (3) co-expression of HHV-8 glycoproteins gH-gL on target cells resulted in inhibition of cell surfacemore » HS expression. Taken together, our results indicate that cell surface HS can play an additional role during HHV-8 pathogenesis.« less
Cagno, Valeria; Donalisio, Manuela; Bugatti, Antonella; Civra, Andrea; Cavalli, Roberta; Ranucci, Elisabetta; Ferruti, Paolo; Rusnati, Marco; Lembo, David
2015-09-01
The agmatine-containing poly(amidoamine) polymer AGMA1 was recently shown to inhibit the infectivity of several viruses, including human papillomavirus 16 (HPV-16), that exploit cell surface heparan sulfate proteoglycans (HSPGs) as attachment receptors. The aim of this work was to assess the antiviral activity of AGMA1 and its spectrum of activity against a panel of low-risk and high-risk HPVs and to elucidate its mechanism of action. AGMA1 was found to be a potent inhibitor of mucosal HPV types (i.e., types 16, 31, 45, and 6) in pseudovirus-based neutralization assays. The 50% inhibitory concentration was between 0.34 μg/ml and 0.73 μg/ml, and no evidence of cytotoxicity was observed. AGMA1 interacted with immobilized heparin and with cellular heparan sulfates, exerting its antiviral action by preventing virus attachment to the cell surface. The findings from this study indicate that AGMA1 is a leading candidate compound for further development as an active ingredient of a topical microbicide against HPV and other sexually transmitted viral infections. Copyright © 2015, American Society for Microbiology. All Rights Reserved.
Klimyte, Edita M.; Smith, Stacy E.; Oreste, Pasqua; Lembo, David
2016-01-01
ABSTRACT Human metapneumovirus (HMPV), a recently discovered paramyxovirus, infects nearly 100% of the world population and causes severe respiratory disease in infants, the elderly, and immunocompromised patients. We previously showed that HMPV binds heparan sulfate proteoglycans (HSPGs) and that HMPV binding requires only the viral fusion (F) protein. To characterize the features of this interaction critical for HMPV binding and the role of this interaction in infection in relevant models, we utilized sulfated polysaccharides, heparan sulfate mimetics, and occluding compounds. Iota-carrageenan demonstrated potent anti-HMPV activity by inhibiting binding to lung cells mediated by the F protein. Furthermore, analysis of a minilibrary of variably sulfated derivatives of Escherichia coli K5 polysaccharide mimicking the HS structure revealed that the highly O-sulfated K5 polysaccharides inhibited HMPV infection, identifying a potential feature of HS critical for HMPV binding. The peptide dendrimer SB105-A10, which binds HS, reduced binding and infection in an F-dependent manner, suggesting that occlusion of HS at the target cell surface is sufficient to prevent infection. HMPV infection was also inhibited by these compounds during apical infection of polarized airway tissues, suggesting that these interactions take place during HMPV infection in a physiologically relevant model. These results reveal key features of the interaction between HMPV and HS, supporting the hypothesis that apical HS in the airway serves as a binding factor during infection, and HS modulating compounds may serve as a platform for potential antiviral development. IMPORTANCE Human metapneumovirus (HMPV) is a paramyxovirus that causes respiratory disease worldwide. It has been previously shown that HMPV requires binding to heparan sulfate on the surfaces of target cells for attachment and infection. In this study, we characterize the key features of this binding interaction using heparan sulfate mimetics, identify an important sulfate modification, and demonstrate that these interactions occur at the apical surface of polarized airway tissues. These findings provide insights into the initial binding step of HMPV infection that has potential for antiviral development. PMID:27489270
Horiguchi, Kotaro; Syaidah, Rahimi; Fujiwara, Ken; Tsukada, Takehiro; Ramadhani, Dini; Jindatip, Depicha; Kikuchi, Motoshi; Yashiro, Takashi
2013-09-01
In the anterior pituitary gland, folliculo-stellate cells and five types of hormone-producing cells are surrounded by an extracellular matrix (ECM) essential for these cells to perform their respective roles. Syndecans-type I transmembrane cell-surface heparan sulfate proteoglycans act as major ECM coreceptors via their respective heparan sulfate chains and efficiently transduce intracellular signals through the convergent action of their transmembrane and cytoplasmic domains. The syndecans comprise four family members in vertebrates: syndecan-1, -2, -3 and -4. However, whether syndecans are produced in the pituitary gland or whether they have a role as a coreceptor is not known. We therefore used (1) reverse transcription plus the polymerase chain reaction to analyze the expression of syndecan genes and (2) immunohistochemical techniques to identify the cells that produce the syndecans in the anterior pituitary gland of adult rat. Syndecan-2 mRNA expression was clearly detected in the corticotropes of the anterior pituitary gland. Moreover, the expression of syndecan-2 in the developing pituitary gland had a distinct temporospatial pattern. To identify the cells expressing syndecan-2 in the developing pituitary gland, we used double-immunohistochemistry for syndecan-2 and the cell markers E-cadherin (immature cells) and Ki-67 (proliferating cells). Some E-cadherin- and Ki-67-immunopositive cells expressed syndecan-2. Therefore, syndecan-2 expression occurs in developmentally regulated patterns and syndecan-2 probably has different roles in adult and developing anterior pituitary glands.
van Det, N F; van den Born, J; Tamsma, J T; Verhagen, N A; Berden, J H; Bruijn, J A; Daha, M R; van der Woude, F J
1996-04-01
Changes in heparan sulfate metabolism may be important in the pathogenesis of diabetic nephropathy. Recent studies performed on renal biopsies from patients with diabetic nephropathy revealed a decrease in heparan sulfate glycosaminoglycan staining in the glomerular basement membrane without changes in staining for heparan sulfate proteoglycan-core protein. To understand this phenomenon at the cellular level, we investigated the effect of high glucose conditions on the synthesis of heparan sulfate proteoglycan by glomerular cells in vitro. Human adult mesangial and glomerular visceral epithelial cells were cultured under normal (5 mM) and high glucose (25 mM) conditions. Immunofluorescence performed on cells cultured in 25 mM glucose confirmed and extended the in vivo histological observations. Using metabolic labeling we observed an altered proteoglycan production under high glucose conditions, with predominantly a decrease in heparan sulfate compared to dermatan sulfate or chondroitin sulfate proteoglycan. N-sulfation analysis of heparan sulfate proteoglycan produced under high glucose conditions revealed less di- and tetrasaccharides compared to larger oligosaccharides, indicating an altered sulfation pattern. Furthermore, with quantification of glomerular basement membrane heparan sulfate by ELISA, a significant decrease was observed when mesangial and visceral epithelial cells were cultured in high glucose conditions. We conclude that high glucose concentration induces a significant alteration of heparan sulfate production by mesangial cells and visceral epithelial cells. Changes in sulfation and changes in absolute quantities are both observed and may explain the earlier in vivo observations. These changes may be of importance for the altered integrity of the glomerular charge-dependent filtration barrier and growth-factor matrix interactions in diabetic nephropathy.
Meade, Kate A.; White, Kathryn J.; Pickford, Claire E.; Holley, Rebecca J.; Marson, Andrew; Tillotson, Donna; van Kuppevelt, Toin H.; Whittle, Jason D.; Day, Anthony J.; Merry, Catherine L. R.
2013-01-01
As our understanding of what guides the behavior of multi- and pluripotent stem cells deepens, so too does our ability to utilize certain cues to manipulate their behavior and maximize their therapeutic potential. Engineered, biologically functionalized materials have the capacity to influence stem cell behavior through a powerful combination of biological, mechanical, and topographical cues. Here, we present the development of a novel electrospun scaffold, functionalized with glycosaminoglycans (GAGs) ionically immobilized onto the fiber surface. Bound GAGs retained the ability to interact with GAG-binding molecules and, crucially, presented GAG sulfation motifs fundamental to mediating stem cell behavior. Bound GAG proved to be biologically active, rescuing the neural differentiation capacity of heparan sulfate-deficient mouse embryonic stem cells and functioning in concert with FGF4 to facilitate the formation of extensive neural processes across the scaffold surface. The combination of GAGs with electrospun scaffolds creates a biomaterial with potent applicability for the propagation and effective differentiation of pluripotent stem cells. PMID:23235146
Meade, Kate A; White, Kathryn J; Pickford, Claire E; Holley, Rebecca J; Marson, Andrew; Tillotson, Donna; van Kuppevelt, Toin H; Whittle, Jason D; Day, Anthony J; Merry, Catherine L R
2013-02-22
As our understanding of what guides the behavior of multi- and pluripotent stem cells deepens, so too does our ability to utilize certain cues to manipulate their behavior and maximize their therapeutic potential. Engineered, biologically functionalized materials have the capacity to influence stem cell behavior through a powerful combination of biological, mechanical, and topographical cues. Here, we present the development of a novel electrospun scaffold, functionalized with glycosaminoglycans (GAGs) ionically immobilized onto the fiber surface. Bound GAGs retained the ability to interact with GAG-binding molecules and, crucially, presented GAG sulfation motifs fundamental to mediating stem cell behavior. Bound GAG proved to be biologically active, rescuing the neural differentiation capacity of heparan sulfate-deficient mouse embryonic stem cells and functioning in concert with FGF4 to facilitate the formation of extensive neural processes across the scaffold surface. The combination of GAGs with electrospun scaffolds creates a biomaterial with potent applicability for the propagation and effective differentiation of pluripotent stem cells.
Handa, A; Muramatsu, S; Qiu, J; Mizukami, H; Brown, K E
2000-08-01
Although adeno-associated virus (AAV)-2 has a broad tissue-host range and can transduce a wide variety of tissue types, some cells, such as erythro-megakaryoblastoid cells, are non-permissive and appear to lack the AAV-2 receptor. However, limited studies have been reported with the related dependovirus AAV-3. We have previously cloned this virus, characterized its genome and produced an infectious clone. In this study, the gene for green fluorescent protein (GFP) was inserted into AAV-2- and AAV-3-based plasmids and recombinant viruses were produced. These viruses were then used to transduce haematopoietic cells and the transduction efficiencies were compared. In contrast to recombinant (r) AAV-2, rAAV-3 successfully transduced erythroid and megakaryoblastoid cells, although rAAV-2 was superior in transduction of lymphocyte-derived cell lines. Recently, it was reported that heparan sulphate can act as a receptor of AAV-2. The infectivity of rAAV-2 and rAAV-3 was tested with mutant cell lines of Chinese hamster ovary cells that were defective for heparin or heparan sulphate expression on the cell surface. There was no correlation between the ability of rAAV-2 or rAAV-3 to infect cells and the cell surface expression of heparan sulphate and, although heparin blocked both rAAV-2 and rAAV-3 transduction, the ID(50) of rAAV-3 was higher than that of rAAV-2. In addition, virus-binding overlay assays indicated that AAV-2 and AAV-3 bound different membrane proteins. These results suggest not only that there are different cellular receptors for AAV-2 and AAV-3, but that rAAV-3 vectors may be preferred for transduction of some haematopoietic cell types.
Ram, Narendra; Aroui, Sonia; Jaumain, Emilie; Bichraoui, Hicham; Mabrouk, Kamel; Ronjat, Michel; Lortat-Jacob, Hugues; De Waard, Michel
2008-01-01
Maurocalcine (MCa), initially identified from a tunisian scorpion venom, defines a new member of the family of cell penetrating peptides by its ability to efficiently cross the plasma membrane. The initiating mechanistic step required for the cell translocation of a cell penetrating peptide implicates its binding onto cell surface components such as membrane lipids and/or heparan sulfate proteoglycans. Here we characterized the interaction of wild-type MCa and MCa K20A, a mutant analogue with reduced cell-penetration efficiency, with heparin (HP) and heparan sulfates (HS) through surface plasma resonance. HP and HS bind both to MCa, indicating that heparan sulfate proteoglycans may represent an important entry route of the peptide. This is confirmed by the fact that (i) both compounds bind with reduced affinity to MCa K20A and (ii) the cell penetration of wild-type or mutant MCa coupled to fluorescent streptavidin is reduced by about 50% in mutant Chinese hamster ovary cell lines lacking either all glycosaminoglycans (GAGs) or just HS. Incubating MCa with soluble HS, HP, or chondroitin sulfates also inhibits the cell penetration of MCa-streptavidin complexes. Analyses of the cell distributions of MCa/streptavidin in several Chinese hamster ovary cell lines show that the distribution of the complex coincides with the endosomal marker Lyso-Tracker red and is not affected by the absence of GAGs. The distribution of MCa/streptavidin is not coincident with that of transferrin receptors nor affected by a dominant-negative dynamin 2 K44A mutant, an inhibitor of clathrin-mediated endocytosis. However, entry of the complex is greatly diminished by amiloride, indicating the importance of macropinocytosis in MCa/streptavidin entry. It is concluded that (i) interaction of MCa with GAGs quantitatively improves the cell penetration of MCa, and (ii) GAG-dependent and -independent MCa penetration rely similarly on the macropinocytosis pathway. PMID:18603532
Autism-like socio-communicative deficits and stereotypies in mice lacking heparan sulfate.
Irie, Fumitoshi; Badie-Mahdavi, Hedieh; Yamaguchi, Yu
2012-03-27
Heparan sulfate regulates diverse cell-surface signaling events, and its roles in the development of the nervous system recently have been increasingly uncovered by studies using genetic models carrying mutations of genes encoding enzymes for its synthesis. On the other hand, the role of heparan sulfate in the physiological function of the adult brain has been poorly characterized, despite several pieces of evidence suggesting its role in the regulation of synaptic function. To address this issue, we eliminated heparan sulfate from postnatal neurons by conditionally inactivating Ext1, the gene encoding an enzyme essential for heparan sulfate synthesis. Resultant conditional mutant mice show no detectable morphological defects in the cytoarchitecture of the brain. Remarkably, these mutant mice recapitulate almost the full range of autistic symptoms, including impairments in social interaction, expression of stereotyped, repetitive behavior, and impairments in ultrasonic vocalization, as well as some associated features. Mapping of neuronal activation by c-Fos immunohistochemistry demonstrates that neuronal activation in response to social stimulation is attenuated in the amygdala in these mice. Electrophysiology in amygdala pyramidal neurons shows an attenuation of excitatory synaptic transmission, presumably because of the reduction in the level of synaptically localized AMPA-type glutamate receptors. Our results demonstrate that heparan sulfate is critical for normal functioning of glutamatergic synapses and that its deficiency mediates socio-communicative deficits and stereotypies characteristic for autism.
Autism-like socio-communicative deficits and stereotypies in mice lacking heparan sulfate
Irie, Fumitoshi; Badie-Mahdavi, Hedieh; Yamaguchi, Yu
2012-01-01
Heparan sulfate regulates diverse cell-surface signaling events, and its roles in the development of the nervous system recently have been increasingly uncovered by studies using genetic models carrying mutations of genes encoding enzymes for its synthesis. On the other hand, the role of heparan sulfate in the physiological function of the adult brain has been poorly characterized, despite several pieces of evidence suggesting its role in the regulation of synaptic function. To address this issue, we eliminated heparan sulfate from postnatal neurons by conditionally inactivating Ext1, the gene encoding an enzyme essential for heparan sulfate synthesis. Resultant conditional mutant mice show no detectable morphological defects in the cytoarchitecture of the brain. Remarkably, these mutant mice recapitulate almost the full range of autistic symptoms, including impairments in social interaction, expression of stereotyped, repetitive behavior, and impairments in ultrasonic vocalization, as well as some associated features. Mapping of neuronal activation by c-Fos immunohistochemistry demonstrates that neuronal activation in response to social stimulation is attenuated in the amygdala in these mice. Electrophysiology in amygdala pyramidal neurons shows an attenuation of excitatory synaptic transmission, presumably because of the reduction in the level of synaptically localized AMPA-type glutamate receptors. Our results demonstrate that heparan sulfate is critical for normal functioning of glutamatergic synapses and that its deficiency mediates socio-communicative deficits and stereotypies characteristic for autism. PMID:22411800
2009-01-01
Background Cationic antimicrobial peptides (CAPs) with antitumor activity constitute a promising group of novel anticancer agents. These peptides induce lysis of cancer cells through interactions with the plasma membrane. It is not known which cancer cell membrane components influence their susceptibility to CAPs. We have previously shown that CAPs interact with the two glycosaminoglycans (GAGs), heparan sulfate (HS) and chondroitin sulfate (CS), which are present on the surface of most cells. The purpose of this study was to investigate the role of the two GAGs in the cytotoxic activity of CAPs. Methods Various cell lines, expressing different levels of cell surface GAGs, were exposed to bovine lactoferricin (LfcinB) and the designer peptide, KW5. The cytotoxic effect of the peptides was investigated by use of the colorimetric MTT viability assay. The cytotoxic effect on wild type CHO cells, expressing normal amounts of GAGs on the cell surface, and the mutant pgsA-745, that has no expression of GAGs on the cell surface, was also investigated. Results We show that cells not expressing HS were more susceptible to CAPs than cells expressing HS at the cell surface. Further, exogenously added heparin inhibited the cytotoxic effect of the peptides. Chondroitin sulfate had no effect on the cytotoxic activity of KW5 and only minor effects on LfcinB cytotoxicity. Conclusion Our results show for the first time that negatively charged molecules at the surface of cancer cells inhibit the cytotoxic activity of CAPs. Our results indicate that HS at the surface of cancer cells sequesters CAPs away from the phospholipid bilayer and thereby impede their ability to induce cytolysis. PMID:19527490
Structural Aspects of N-Glycosylations and the C-terminal Region in Human Glypican-1*
Awad, Wael; Adamczyk, Barbara; Örnros, Jessica; Karlsson, Niclas G.; Mani, Katrin; Logan, Derek T.
2015-01-01
Glypicans are multifunctional cell surface proteoglycans involved in several important cellular signaling pathways. Glypican-1 (Gpc1) is the predominant heparan sulfate proteoglycan in the developing and adult human brain. The two N-linked glycans and the C-terminal domain that attach the core protein to the cell membrane are not resolved in the Gpc1 crystal structure. Therefore, we have studied Gpc1 using crystallography, small angle x-ray scattering, and chromatographic approaches to elucidate the composition, structure, and function of the N-glycans and the C terminus and also the topology of Gpc1 with respect to the membrane. The C terminus is shown to be highly flexible in solution, but it orients the core protein transverse to the membrane, directing a surface evolutionarily conserved in Gpc1 orthologs toward the membrane, where it may interact with signaling molecules and/or membrane receptors on the cell surface, or even the enzymes involved in heparan sulfate substitution in the Golgi apparatus. Furthermore, the N-glycans are shown to extend the protein stability and lifetime by protection against proteolysis and aggregation. PMID:26203194
Mucin (MUC1) Expression and Function in Prostate Cancer Cells
2001-09-01
Interactions at the Cell Surface of Mouse Uterine Epithelial Cells and Periimplantation -Stage Embryos. Trophoblast Res., 4:211-241, 1990. 37. Dutt...and Julian, J. Heparan Sulfate Proteoglycan Expression by Periimplantation Stage Embryos. Dev. Biol. 155:97-106,1993. 56. Rohde, L.H., and Carson...Modulators of Embryo-Uterine Epithelial Cell Attachment. In: S.K. Dey (ed.), Molecular and Cellular Aspects of Periimplantation Processes, Springer
The role of heparins and nano-heparins as therapeutic tool in breast cancer.
Afratis, Nikos A; Karamanou, Konstantina; Piperigkou, Zoi; Vynios, Demitrios H; Theocharis, Achilleas D
2017-06-01
Glycosaminoglycans are integral part of the dynamic extracellular matrix (ECM) network that control crucial biochemical and biomechanical signals required for tissue morphogenesis, differentiation, homeostasis and cancer development. Breast cancer cells communicate with stromal ones to modulate ECM mainly through release of soluble effectors during cancer progression. The intracellular cross-talk between cell surface receptors and estrogen receptors is important for the regulation of breast cancer cell properties and production of ECM molecules. In turn, reorganized ECM-cell surface interface modulates signaling cascades, which regulate almost all aspects of breast cell behavior. Heparan sulfate chains present on cell surface and matrix proteoglycans are involved in regulation of breast cancer functions since they are capable of binding numerous matrix molecules, growth factors and inflammatory mediators thus modulating their signaling. In addition to its anticoagulant activity, there is accumulating evidence highlighting various anticancer activities of heparin and nano-heparin derivatives in numerous types of cancer. Importantly, heparin derivatives significantly reduce breast cancer cell proliferation and metastasis in vitro and in vivo models as well as regulates the expression profile of major ECM macromolecules, providing strong evidence for therapeutic targeting. Nano-formulations of the glycosaminoglycan heparin are possibly novel tools for targeting tumor microenvironment. In this review, the role of heparan sulfate/heparin and its nano-formulations in breast cancer biology are presented and discussed in terms of future pharmacological targeting.
A role for Heparan Sulfate in Viral Surfing
Oh, Myung-Jin; Akhtar, Jihan; Desai, Prashant; Shukla, Deepak
2009-01-01
Heparan sulfate (HS) moieties on cell surfaces are known to provide attachment sites for many viruses including herpes simplex virus type-1 (HSV-1). Here we demonstrate that cells respond to HSV-1 infection by promoting filopodia formation. Filopodia express HS and are subsequently utilized for the transport of HSV-1 virions to cell bodies in a surfing-like phenomenon, which is facilitated by the underlying actin cytoskeleton and is regulated by transient activation of a small Rho GTPase, Cdc42. We also demonstrate that interaction between a highly conserved herpesvirus envelope glycoprotein B (gB) and HS is required for surfing. A HSV-1 mutant that lacks gB fails to surf and quantum-dots conjugated with gB demonstrate surfing-like movements. Our data demonstrates a novel use of a common receptor, HS, which could also be exploited by multiple viruses and quite possibly, many additional ligands for transport along the plasma membrane. PMID:19909728
Roles of Heparan Sulfate Sulfation in Dentinogenesis*
Hayano, Satoru; Kurosaka, Hiroshi; Yanagita, Takeshi; Kalus, Ina; Milz, Fabian; Ishihara, Yoshihito; Islam, Md. Nurul; Kawanabe, Noriaki; Saito, Masahiro; Kamioka, Hiroshi; Adachi, Taiji; Dierks, Thomas; Yamashiro, Takashi
2012-01-01
Cell surface heparan sulfate (HS) is an essential regulator of cell signaling and development. HS traps signaling molecules, like Wnt in the glycosaminoglycan side chains of HS proteoglycans (HSPGs), and regulates their functions. Endosulfatases Sulf1 and Sulf2 are secreted at the cell surface to selectively remove 6-O-sulfate groups from HSPGs, thereby modifying the affinity of cell surface HSPGs for its ligands. This study provides molecular evidence for the functional roles of HSPG sulfation and desulfation in dentinogenesis. We show that odontogenic cells are highly sulfated on the cell surface and become desulfated during their differentiation to odontoblasts, which produce tooth dentin. Sulf1/Sulf2 double null mutant mice exhibit a thin dentin matrix and short roots combined with reduced expression of dentin sialophosphoprotein (Dspp) mRNA, encoding a dentin-specific extracellular matrix precursor protein, whereas single Sulf mutants do not show such defective phenotypes. In odontoblast cell lines, Dspp mRNA expression is potentiated by the activation of the Wnt canonical signaling pathway. In addition, pharmacological interference with HS sulfation promotes Dspp mRNA expression through activation of Wnt signaling. On the contrary, the silencing of Sulf suppresses the Wnt signaling pathway and subsequently Dspp mRNA expression. We also show that Wnt10a protein binds to cell surface HSPGs in odontoblasts, and interference with HS sulfation decreases the binding affinity of Wnt10a for HSPGs, which facilitates the binding of Wnt10a to its receptor and potentiates the Wnt signaling pathway, thereby up-regulating Dspp mRNA expression. These results demonstrate that Sulf-mediated desulfation of cellular HSPGs is an important modification that is critical for the activation of the Wnt signaling in odontoblasts and for production of the dentin matrix. PMID:22351753
7-Day Biodefense: Engineered Nanoparticle for Virus Elimination by Opsonization (ENVELOP)
2013-12-10
spectrum for LSTc, specifically the identity of the four distinct monosaccharides and the presence of 2→6 sialic acid at stoichimetric levels. 7-Day...A. Previous studies definitively demonstrated that cell surface heparan sulfate, a complex highly charged polysaccharide , plays an important role in
Heparan sulfate proteoglycans mediate renal carcinoma metastasis.
Qazi, Henry; Shi, Zhong-Dong; Song, Jonathan W; Cancel, Limary M; Huang, Peigen; Zeng, Ye; Roberge, Sylvie; Munn, Lance L; Tarbell, John M
2016-12-15
The surface proteoglycan/glycoprotein layer (glycocalyx) on tumor cells has been associated with cellular functions that can potentially enable invasion and metastasis. In addition, aggressive tumor cells with high metastatic potential have enhanced invasion rates in response to interstitial flow stimuli in vitro. Our previous studies suggest that heparan sulfate (HS) in the glycocalyx plays an important role in this flow mediated mechanostransduction and upregulation of invasive and metastatic potential. In this study, highly metastatic renal cell carcinoma cells were genetically modified to suppress HS production by knocking down its synthetic enzyme NDST1. Using modified Boyden chamber and microfluidic assays, we show that flow-enhanced invasion is suppressed in HS deficient cells. To assess the ability of these cells to metastasize in vivo, parental or knockdown cells expressing fluorescence reporters were injected into kidney capsules in SCID mice. Histological analysis confirmed that there was a large reduction (95%) in metastasis to distant organs by tumors formed from the NDST1 knockdown cells compared to control cells with intact HS. The ability of these cells to invade surrounding tissue was also impaired. The substantial inhibition of metastasis and invasion upon reduction of HS suggests an active role for the tumor cell glycocalyx in tumor progression. © 2016 UICC.
Viola, Manuela; Brüggemann, Kathrin; Karousou, Evgenia; Caon, Ilaria; Caravà, Elena; Vigetti, Davide; Greve, Burkhard; Stock, Christian; De Luca, Giancarlo; Passi, Alberto; Götte, Martin
2017-06-01
Proteoglycans and glycosaminoglycans modulate numerous cellular processes relevant to tumour progression, including cell proliferation, cell-matrix interactions, cell motility and invasive growth. Among the glycosaminoglycans with a well-documented role in tumour progression are heparan sulphate, chondroitin/dermatan sulphate and hyaluronic acid/hyaluronan. While the mode of biosynthesis differs for sulphated glycosaminoglycans, which are synthesised in the ER and Golgi compartments, and hyaluronan, which is synthesized at the plasma membrane, these polysaccharides partially compete for common substrates. In this study, we employed a siRNA knockdown approach for heparan sulphate (EXT1) and heparan/chondroitin/dermatan sulphate-biosynthetic enzymes (β4GalT7) in the aggressive human breast cancer cell line MDA-MB-231 to study the impact on cell behaviour and hyaluronan biosynthesis. Knockdown of β4GalT7 expression resulted in a decrease in cell viability, motility and adhesion to fibronectin, while these parameters were unchanged in EXT1-silenced cells. Importantly, these changes were associated with a decreased expression of syndecan-1, decreased signalling response to HGF and an increase in the synthesis of hyaluronan, due to an upregulation of the hyaluronan synthases HAS2 and HAS3. Interestingly, EXT1-depleted cells showed a downregulation of the UDP-sugar transporter SLC35D1, whereas SLC35D2 was downregulated in β4GalT7-depleted cells, indicating an intricate regulatory network that connects all glycosaminoglycans synthesis. The results of our in vitro study suggest that a modulation of breast cancer cell behaviour via interference with heparan sulphate biosynthesis may result in a compensatory upregulation of hyaluronan biosynthesis. These findings have important implications for the development of glycosaminoglycan-targeted therapeutic approaches for malignant diseases.
1994-01-01
Heparan sulfate proteoglycans (HSPGs) are found on the surface of all adherent cells and participate in the binding of growth factors, extracellular matrix glycoproteins, cell adhesion molecules, and proteases and antiproteases. We report here the cloning and pattern of expression of cerebroglycan, a glycosylphosphatidylinositol (GPI)- anchored HSPG that is found in the developing rat brain (previously referred to as HSPG M13; Herndon, M. E., and A. D. Lander. 1990. Neuron. 4:949-961). The cerebroglycan core protein has a predicted molecular mass of 58.6 kD and five potential heparan sulfate attachment sites. Together with glypican (David, G., V. Lories, B. Decock, P. Marynen, J.-J. Cassiman, and H. Van den Berghe. 1990. J. Cell Biol. 111:3165-3176), it defines a family of integral membrane HSPGs characterized by GPI linkage and conserved structural motifs, including a pattern of 14 cysteine residues that is absolutely conserved. Unlike other known integral membrane HSPGs, including glypican and members of the syndecan family of transmembrane proteoglycans, cerebroglycan is expressed in only one tissue: the nervous system. In situ hybridization experiments at several developmental stages strongly suggest that cerebroglycan message is widely and transiently expressed by immature neurons, appearing around the time of final mitosis and disappearing after cell migration and axon outgrowth have been completed. These results suggest that cerebroglycan may fulfill a function related to the motile behaviors of developing neurons. PMID:8294498
A role for heparan sulfate in viral surfing
DOE Office of Scientific and Technical Information (OSTI.GOV)
Oh, Myung-Jin; Akhtar, Jihan; Desai, Prashant
2010-01-01
Heparan sulfate (HS) moieties on cell surfaces are known to provide attachment sites for many viruses including herpes simplex virus type-1 (HSV-1). Here, we demonstrate that cells respond to HSV-1 infection by enhancing filopodia formation. Filopodia express HS and are subsequently utilized for the transport of HSV-1 virions to cell bodies in a surfing-like phenomenon, which is facilitated by the underlying actin cytoskeleton and is regulated by transient activation of a small Rho GTPase, Cdc42. We also demonstrate that interaction between a highly conserved herpesvirus envelope glycoprotein B (gB) and HS is required for surfing. A HSV-1 mutant that lacksmore » gB fails to surf and quantum dots conjugated with gB demonstrate surfing-like movements. Our data demonstrates a novel use of a common receptor, HS, which could also be exploited by multiple viruses and quite possibly, many additional ligands for transport along the plasma membrane.« less
Genetics Home Reference: hereditary multiple osteochondromas
... exostosin-2 complex modifies a protein called heparan sulfate so it can be used by the cell. ... mutation in exostosin-1 or exostosin-2, heparan sulfate cannot be processed correctly and is nonfunctional. Although ...
Williamson, Kate A; Hamilton, Andrew; Reynolds, John A; Sipos, Peter; Crocker, Ian; Stringer, Sally E; Alexander, Yvonne M
2013-02-01
Aging poses one of the largest risk factors for the development of cardiovascular disease. The increased propensity toward vascular pathology with advancing age maybe explained, in part, by a reduction in the ability of circulating endothelial progenitor cells to contribute to vascular repair and regeneration. Although there is evidence to suggest that colony forming unit-Hill cells and circulating angiogenic cells are subject to age-associated changes that impair their function, the impact of aging on human outgrowth endothelial cell (OEC) function has been less studied. We demonstrate that OECs isolated from cord blood or peripheral blood samples from young and old individuals exhibit different characteristics in terms of their migratory capacity. In addition, age-related structural changes were discovered in OEC heparan sulfate (HS), a glycocalyx component that is essential in many signalling pathways. An age-associated decline in the migratory response of OECs toward a gradient of VEGF significantly correlated with a reduction in the relative percentage of the trisulfated disaccharide, 2-O-sulfated-uronic acid, N, 6-O-sulfated-glucosamine (UA[2S]-GlcNS[6S]), within OEC cell surface HS polysaccharide chains. Furthermore, disruption of cell surface HS reduced the migratory response of peripheral blood-derived OECs isolated from young subjects to levels similar to that observed for OECs from older individuals. Together these findings suggest that aging is associated with alterations in the fine structure of HS on the cell surface of OECs. Such changes may modulate the migration, homing, and engraftment capacity of these repair cells, thereby contributing to the progression of endothelial dysfunction and age-related vascular pathologies. © 2012 The Authors Aging Cell © 2012 Blackwell Publishing Ltd/Anatomical Society of Great Britain and Ireland.
Beccati, Daniela; Lech, Miroslaw; Ozug, Jennifer; Gunay, Nur Sibel; Wang, Jing; Sun, Elaine Y; Pradines, Joël R; Farutin, Victor; Shriver, Zachary; Kaundinya, Ganesh V; Capila, Ishan
2017-02-01
Heparan sulfate (HS), a glycosaminoglycan present on the surface of cells, has been postulated to have important roles in driving both normal and pathological physiologies. The chemical structure and sulfation pattern (domain structure) of HS is believed to determine its biological function, to vary across tissue types, and to be modified in the context of disease. Characterization of HS requires isolation and purification of cell surface HS as a complex mixture. This process may introduce additional chemical modification of the native residues. In this study, we describe an approach towards thorough characterization of bovine kidney heparan sulfate (BKHS) that utilizes a variety of orthogonal analytical techniques (e.g. NMR, IP-RPHPLC, LC-MS). These techniques are applied to characterize this mixture at various levels including composition, fragment level, and overall chain properties. The combination of these techniques in many instances provides orthogonal views into the fine structure of HS, and in other instances provides overlapping / confirmatory information from different perspectives. Specifically, this approach enables quantitative determination of natural and modified saccharide residues in the HS chains, and identifies unusual structures. Analysis of partially digested HS chains allows for a better understanding of the domain structures within this mixture, and yields specific insights into the non-reducing end and reducing end structures of the chains. This approach outlines a useful framework that can be applied to elucidate HS structure and thereby provides means to advance understanding of its biological role and potential involvement in disease progression. In addition, the techniques described here can be applied to characterization of heparin from different sources.
Kaur, Sukhbir; Kuznetsova, Svetlana A.; Pendrak, Michael L.; Sipes, John M.; Romeo, Martin J.; Li, Zhuqing; Zhang, Lijuan; Roberts, David D.
2011-01-01
Cell surface proteoglycans on T cells contribute to retroviral infection, binding of chemokines and other proteins, and are necessary for some T cell responses to the matricellular glycoprotein thrombospondin-1. The major cell surface proteoglycans expressed by primary T cells and Jurkat T cells have an apparent Mr > 200,000 and are modified with chondroitin sulfate and heparan sulfate chains. Thrombospondin-1 bound in a heparin-inhibitable manner to this proteoglycan and to a soluble form released into the medium. Based on mass spectrometry, knockdown, and immunochemical analyses, the proteoglycan contains two major core proteins as follows: amyloid precursor-like protein-2 (APLP2, apparent Mr 230,000) and CD47 (apparent Mr > 250,000). CD47 is a known thrombospondin-1 receptor but was not previously reported to be a proteoglycan. This proteoglycan isoform of CD47 is widely expressed on vascular cells. Mutagenesis identified glycosaminoglycan modification of CD47 at Ser64 and Ser79. Inhibition of T cell receptor signaling by thrombospondin-1 was lost in CD47-deficient T cells that express the proteoglycan isoform of APLP2, indicating that binding to APLP2 is not sufficient. Inhibition of CD69 induction was restored in CD47-deficient cells by re-expressing CD47 or an S79A mutant but not by the S64A mutant. Therefore, inhibition of T cell receptor signaling by thrombospondin-1 is mediated by CD47 and requires its modification at Ser64. PMID:21343308
Sadir, Rabia; Imberty, Anne; Baleux, Françoise; Lortat-Jacob, Hugues
2004-10-15
Stromal cell-derived factor-1 (SDF-1) is a CXC chemokine that is constitutively expressed in most tissues and displayed on the cell surface in association with heparan sulfate (HS). Its numerous biological effects are mediated by a specific G protein-coupled receptor, CXCR4. A number of cells inactivate SDF-1 by specific processing of the N-terminal domain of the chemokine. In particular, CD26/dipeptidyl peptidase IV (DPP IV), a serine protease that co-distributes with CXCR4 at the cell surface, mediates the selective removal of the N-terminal dipeptide of SDF-1. We report here that heparin and HS specifically prevent the processing of SDF-1 by DPP IV expressed by Caco-2 cells. The level of processing increases with the level of differentiation of these cells, which correlates with an increase of DPP IV activity. A mutant SDF-1 that does not interact with HS is readily cleaved by DPP IV, a process that is not inhibited by HS, demonstrating that a productive interaction between HS and SDF-1 is required for the protection to take place. Moreover, we found that protection depends on the degree of polymerization of the HS sulfated S-domains. Finally a structural model of SDF-1, in complex with HS oligosaccharides of defined length, rationalizes the experimental data. The mechanisms by which HS regulates SDF-1 may thus include, in addition to its ability to locally concentrate the chemokine at the cell surface, a control of selective protease cleavage events that directly affect the chemokine activity.
[Heparan sulphates, amyloidosis and neurodegeneration].
Vera, C; Alvarez-Orozco, J A; Maiza, A; Chantepie, S; Chehin, R N; Ouidja, M O; Papy-Garcia, D
2017-11-16
A number of neurodegenerative disorders have been linked directly to the accumulation of amyloid fibres. These fibres are made up of proteins or peptides with altered structures and which join together in vivo in association with heparan sulphate-type polysaccharides. To examine the most recent concepts in the biology of heparan sulphates and their role in the aggregation of the peptide Abeta, of tau protein, of alpha-synuclein and of prions. The study also seeks to analyse their implications in neurodegenerative disorders such as Alzheimer's and Parkinson's disease and prion diseases. In vitro, heparan sulphates have played an important role in the process of oligomerisation and fibrillation of amyloidogenic proteins or peptides, in the stabilisation of these bodies and their resistance to proteolysis, thereby participating in the formation of a wide range of amyloid fibres. Heparan sulphates have also been related to the internalisation of pro-amyloid fibres during the process of intercellular propagation (spreading), which is considered to be crucial in the development of proteinopathies, the best example of which is Alzheimer's disease. This study suggests that the fine structures of heparan sulphates, their localisation in cells and tissues, together with their local concentration, may regulate the amyloidosis processes. The advances made in the understanding of this area of glyconeurobiology will make it possible to improve the understanding of the cell and molecular mechanisms underlying the neurodegenerative process.
Huang, Teng-Yi; Irene, Deli; Zulueta, Medel Manuel L; Tai, Tzu-Jui; Lain, Shih-Han; Cheng, Cheng-Po; Tsai, Ping-Xi; Lin, Shu-Yi; Chen, Zhi-Geng; Ku, Chiao-Chu; Hsiao, Chwan-Deng; Chyan, Chia-Lin; Hung, Shang-Cheng
2017-04-03
Heparin-binding hemagglutinin (HBHA) is a 199 amino acid virulence factor at the envelope of Mycobacterium tuberculosis that contributes to latent tuberculosis. The binding of HBHA to respiratory epithelial cells, which leads to extrapulmonary dissemination of the pathogen, is mediated by cell-surface heparan sulfate (HS). We report the structural characterization of the HBHA/HS complex by NMR spectroscopy. To develop a model for the molecular recognition, the first chemically synthesized uniformly 13 C- and 15 N-labeled HS octasaccharide and a uniformly 13 C- and 15 N-labeled form of HBHA were prepared. Residues 180-195 at the C-terminal region of HBHA show large chemical shift perturbation upon association with the octasaccharide. Molecular dynamics simulations conforming to the multidimensional NMR data revealed key electrostatic and even hydrophobic interactions between the binding partners that may aid in the development of agents targeting the binding event. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Chang, Andres; Masante, Cyril; Buchholz, Ursula J.
2012-01-01
Human metapneumovirus (HMPV) is a major worldwide respiratory pathogen that causes acute upper and lower respiratory tract disease. The mechanism by which this virus recognizes and gains access to its target cell is still largely unknown. In this study, we addressed the initial steps in virus binding and infection and found that the first binding partner for HMPV is heparan sulfate (HS). While wild-type CHO-K1 cells are permissive to HMPV infection, mutant cell lines lacking the ability to synthesize glycosaminoglycans (GAGs), specifically, heparan sulfate proteoglycans (HSPGs), were resistant to binding and infection by HMPV. The permissiveness to HMPV infection was also abolished when CHO-K1 cells were treated with heparinases. Importantly, using recombinant HMPV lacking both the G and small hydrophobic (SH) proteins, we report that this first virus-cell binding interaction is driven primarily by the fusion protein (HMPV F) and that this interaction is needed to establish a productive infection. Finally, HMPV binding to cells did not require β1 integrin expression, and RGD-mediated interactions were not essential in promoting HMPV F-mediated cell-to-cell membrane fusion. Cells lacking β1 integrin, however, were less permissive to HMPV infection, indicating that while β1 integrins play an important role in promoting HMPV infection, the interaction between integrins and HMPV occurs after the initial binding of HMPV F to heparan sulfate proteoglycans. PMID:22238303
Differential expression of syndecan isoforms during mouse incisor amelogenesis.
Muto, Taro; Miyoshi, Keiko; Munesue, Seiichi; Nakada, Hiroshi; Okayama, Minoru; Matsuo, Takashi; Noma, Takafumi
2007-08-01
Syndecans are transmembranous heparan sulfate proteoglycans (HSPGs) with covalently attached glycosaminoglycan side-chains located on the cell surface. The mammalian syndecan family is composed of four types of syndecans (syndecan-1 to -4). Syndecans interact with the intracellular cytoskeleton through the cytoplasmic domains of their core proteins and membrane proteins, extracellular enzymes, growth factors, and matrix components, through their heparan-sulfate chains, to regulate developmental processes.Here, as a first step to assess the possible roles of syndecan proteins in amelogenesis, we examined the expression patterns of all syndecan isoforms in continuously growing mouse incisors, in which we can overview major differentiation stages of amelogenesis at a glance. Understanding the expression domain of each syndecan isoform during specific developmental stages seems useful for investigating their physiological roles in amelogenesis. Immunohistochemical analysis of syndecan core proteins in the lower incisors from postnatal day 1 mice revealed spatially and temporally specific expression patterns, with syndecan-1 expressed in undifferentiated epithelial and mesenchymal cells, and syndecan-2, -3, and -4 in more differentiated cells. These findings suggest that each syndecan isoform functions distinctly during the amelogenesis of the incisors of mice.
Epithelial heparan sulfate regulates Sonic Hedgehog signaling in lung development.
He, Hua; Huang, Meina; Sun, Shenfei; Wu, Yihui; Lin, Xinhua
2017-08-01
The tree-like structure of the mammalian lung is generated from branching morphogenesis, a reiterative process that is precisely regulated by numerous factors. How the cell surface and extra cellular matrix (ECM) molecules regulate this process is still poorly understood. Herein, we show that epithelial deletion of Heparan Sulfate (HS) synthetase Ext1 resulted in expanded branching tips and reduced branching number, associated with several mesenchymal developmental defects. We further demonstrate an expanded Fgf10 expression and increased FGF signaling activity in Ext1 mutant lungs, suggesting a cell non-autonomous mechanism. Consistent with this, we observed reduced levels of SHH signaling which is responsible for suppressing Fgf10 expression. Moreover, reactivating SHH signaling in mutant lungs rescued the tip dilation phenotype and attenuated FGF signaling. Importantly, the reduced SHH signaling activity did not appear to be caused by decreased Shh expression or protein stability; instead, biologically active form of SHH proteins were reduced in both the Ext1 mutant epithelium and surrounding wild type mesenchymal cells. Together, our study highlights the epithelial HS as a key player for dictating SHH signaling critical for lung morphogenesis.
NASA Astrophysics Data System (ADS)
Zhao, Yuejie; Singh, Arunima; Xu, Yongmei; Zong, Chengli; Zhang, Fuming; Boons, Geert-Jan; Liu, Jian; Linhardt, Robert J.; Woods, Robert J.; Amster, I. Jonathan
2017-01-01
Fibroblast growth factors (FGFs) regulate several cellular developmental processes by interacting with cell surface heparan proteoglycans and transmembrane cell surface receptors (FGFR). The interaction of FGF with heparan sulfate (HS) is known to induce protein oligomerization, increase the affinity of FGF towards its receptor FGFR, promoting the formation of the HS-FGF-FGFR signaling complex. Although the role of HS in the signaling pathways is well recognized, the details of FGF oligomerization and formation of the ternary signaling complex are still not clear, with several conflicting models proposed in literature. Here, we examine the effect of size and sulfation pattern of HS upon FGF1 oligomerization, binding stoichiometry and conformational stability, through a combination of ion mobility (IM) and theoretical modeling approaches. Ion mobility-mass spectrometry (IMMS) of FGF1 in the presence of several HS fragments ranging from tetrasaccharide (dp4) to dodecasaccharide (dp12) in length was performed. A comparison of the binding stoichiometry of variably sulfated dp4 HS to FGF1 confirmed the significance of the previously known high-affinity binding motif in FGF1 dimerization, and demonstrated that certain tetrasaccharide-length fragments are also capable of inducing dimerization of FGF1. The degree of oligomerization was found to increase in the presence of dp12 HS, and a general lack of specificity for longer HS was observed. Additionally, collision cross-sections (CCSs) of several FGF1-HS complexes were calculated, and were found to be in close agreement with experimental results. Based on the (CCSs) a number of plausible binding modes of 2:1 and 3:1 FGF1-HS are proposed.
Antiretroviral Activity Of a Novel Pyrimidyl-Di(Diazaspiroalkane) Derivative.
Novoselova, E A; Riabova, O B; Leneva, I A; Nesterenko, V G; Bolgarin, R N; Makarov, V A
2017-01-01
A novel compound, 3,3'-(5-nitropyrimidine-4,6-diyl)bis-3,12-diaza-6,9-diazoniadispiro[5.2.5.2]hexadecane tetrachloride dihydrochloride, was synthesized. The compound was found to inhibit the replication of various viral families by blocking specific heparan sulfate receptors on the host cell's surface. In experiments, the compound was found to be highly effective against several strains of HIV retroviruses.
Takemura, Masahiko; Nakato, Hiroshi
2017-01-15
Stem cell division is activated to trigger regeneration in response to tissue damage. The molecular mechanisms by which this stem cell mitotic activity is properly repressed at the end of regeneration are poorly understood. Here, we show that a specific modification of heparan sulfate is crucial for regulating Drosophila intestinal stem cell (ISC) division during normal midgut homeostasis and regeneration. Loss of the extracellular heparan sulfate endosulfatase Sulf1 resulted in increased ISC division during normal homeostasis, which was caused by upregulation of mitogenic signaling including the JAK-STAT, EGFR and Hedgehog pathways. Using a regeneration model, we found that ISCs failed to properly halt division at the termination stage in Sulf1 mutants, showing that Sulf1 is required for terminating ISC division at the end of regeneration. We propose that post-transcriptional regulation of mitogen signaling by heparan sulfate structural modifications provides a new regulatory step for precise temporal control of stem cell activity during regeneration. © 2017. Published by The Company of Biologists Ltd.
2017-01-01
ABSTRACT Stem cell division is activated to trigger regeneration in response to tissue damage. The molecular mechanisms by which this stem cell mitotic activity is properly repressed at the end of regeneration are poorly understood. Here, we show that a specific modification of heparan sulfate is crucial for regulating Drosophila intestinal stem cell (ISC) division during normal midgut homeostasis and regeneration. Loss of the extracellular heparan sulfate endosulfatase Sulf1 resulted in increased ISC division during normal homeostasis, which was caused by upregulation of mitogenic signaling including the JAK-STAT, EGFR and Hedgehog pathways. Using a regeneration model, we found that ISCs failed to properly halt division at the termination stage in Sulf1 mutants, showing that Sulf1 is required for terminating ISC division at the end of regeneration. We propose that post-transcriptional regulation of mitogen signaling by heparan sulfate structural modifications provides a new regulatory step for precise temporal control of stem cell activity during regeneration. PMID:27888216
Propagation of classical swine fever virus in vitro circumventing heparan sulfate-adaptation.
Eymann-Häni, Rita; Leifer, Immanuel; McCullough, Kenneth C; Summerfield, Artur; Ruggli, Nicolas
2011-09-01
Amplification of natural virus isolates in permanent cell lines can result in adaptation, in particular enhanced binding to heparan sulfate (HS)-containing glycosaminoglycans present on most vertebrate cells. This has been reported for several viruses, including the pestivirus classical swine fever virus (CSFV), the causative agent of a highly contagious hemorrhagic disease in pigs. Propagation of CSFV in cell culture is essential in virus diagnostics and research. Adaptation of CSFV to HS-binding has been related to amino acid changes in the viral E(rns) glycoprotein, resulting in viruses with altered replication characteristics in vitro and in vivo. Consequently, a compound blocking the HS-containing structures on cell surfaces was employed to monitor conversion from HS-independency to HS-dependency. It was shown that the porcine PEDSV.15 cell line permitted propagation of CSFV within a limited number of passages without adaptation to HS-binding. The selection of HS-dependent CSFV mutants was also prevented by propagation of the virus in the presence of DSTP 27. The importance of these findings can be seen from the altered ratio of cell-associated to secreted virus upon acquisition of enhanced HS-binding affinity, a phenotype proposed previously to be related to virulence in the natural host. Copyright © 2011 Elsevier B.V. All rights reserved.
The heparanome--the enigma of encoding and decoding heparan sulfate sulfation.
Lamanna, William C; Kalus, Ina; Padva, Michael; Baldwin, Rebecca J; Merry, Catherine L R; Dierks, Thomas
2007-04-30
Heparan sulfate (HS) is a cell surface carbohydrate polymer modified with sulfate moieties whose highly ordered composition is central to directing specific cell signaling events. The ability of the cell to generate these information rich glycans with such specificity has opened up a new field of "heparanomics" which seeks to understand the systems involved in generating these cell type and developmental stage specific HS sulfation patterns. Unlike other instances where biological information is encrypted as linear sequences in molecules such as DNA, HS sulfation patterns are generated through a non-template driven process. Thus, deciphering the sulfation code and the dynamic nature of its generation has posed a new challenge to system biologists. The recent discovery of two sulfatases, Sulf1 and Sulf2, with the unique ability to edit sulfation patterns at the cell surface, has opened up a new dimension as to how we understand the regulation of HS sulfation patterning and pattern-dependent cell signaling events. This review will focus on the functional relationship between HS sulfation patterning and biological processes. Special attention will be given to Sulf1 and Sulf2 and how these key editing enzymes might act in concert with the HS biosynthetic enzymes to generate and regulate specific HS sulfation patterns in vivo. We will further explore the use of knock out mice as biological models for understanding the dynamic systems involved in generating HS sulfation patterns and their biological relevance. A brief overview of new technologies and innovations summarizes advances in the systems biology field for understanding non-template molecular networks and their influence on the "heparanome".
Small lytic peptides escape the inhibitory effect of heparan sulfate on the surface of cancer cells
2011-01-01
Background Several naturally occurring cationic antimicrobial peptides (CAPs), including bovine lactoferricin (LfcinB), display promising anticancer activities. These peptides are unaffected by multidrug resistance mechanisms and have been shown to induce a protective immune response against solid tumors, thus making them interesting candidates for developing novel lead structures for anticancer treatment. Recently, we showed that the anticancer activity by LfcinB was inhibited by the presence of heparan sulfate (HS) on the surface of tumor cells. Based on extensive structure-activity relationship studies performed on LfcinB, shorter and more potent peptides have been constructed. In the present study, we have investigated the anticancer activity of three chemically modified 9-mer peptides and the influence of HS and chondroitin sulfate (CS) on their cytotoxic activity. Methods Various cell lines and red blood cells were used to investigate the anticancer activity and selectivity of the peptides. The cytotoxic effect of the peptides against the different cell lines was measured by use of a colorimetric MTT viability assay. The influence of HS and CS on their cytotoxic activity was evaluated by using HS/CS expressing and HS/CS deficient cell lines. The ability of soluble HS and CS to inhibit the cytotoxic activity of the peptides and the peptides' affinity for HS and CS were also investigated. Results The 9-mer peptides displayed selective anticancer activity. Cells expressing HS/CS were equally or more susceptible to the peptides than cells not expressing HS/CS. The peptides displayed a higher affinity for HS compared to CS, and exogenously added HS inhibited the cytotoxic effect of the peptides. Conclusions In contrast to the previously reported inhibitory effect of HS on LfcinB, the present study shows that the cytotoxic activity of small lytic peptides was increased or not affected by cell surface HS. PMID:21453492
Chang, Yung-Heng; Sun, Yi Henry
2014-01-01
Morphogens are signaling molecules that regulate growth and patterning during development by forming a gradient and activating different target genes at different concentrations. The extracellular distribution of morphogens is tightly regulated, with the Drosophila morphogen Wingless (Wg) relying on Dally-like (Dlp) and transcytosis for its distribution. However, in the absence of Dlp or endocytic activity, Wg can still move across cells along the apical (Ap) surface. We identified a novel secreted heparan sulfate proteoglycan (HSPG) that binds to Wg and promotes its extracellular distribution by increasing Wg mobility, which was thus named Carrier of Wg (Cow). Cow promotes the Ap transport of Wg, independent of Dlp and endocytosis, and this function addresses a previous gap in the understanding of Wg movement. This is the first example of a diffusible HSPG acting as a carrier to promote the extracellular movement of a morphogen. PMID:25360738
Heparan sulfate C5-epimerase is essential for heparin biosynthesis in mast cells.
Feyerabend, Thorsten B; Li, Jin-Ping; Lindahl, Ulf; Rodewald, Hans-Reimer
2006-04-01
Biosynthesis of heparin, a mast cell-derived glycosaminoglycan with widespread importance in medicine, has not been fully elucidated. In biosynthesis of heparan sulfate (HS), a structurally related polysaccharide, HS glucuronyl C5-epimerase (Hsepi) converts D-glucuronic acid (GlcA) to L-iduronic acid (IdoA) residues. We have generated Hsepi-null mouse mutant mast cells, and we show that the same enzyme catalyzes the generation of IdoA in heparin and that 'heparin' lacking IdoA shows a distorted O-sulfation pattern.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dahms, Sven O., E-mail: sdahms@fli-leibniz.de; Mayer, Magnus C.; Miltenyi Biotec GmbH, Robert-Koch-Strasse 1, 17166 Teterow
2015-03-01
Two X-ray structures of APLP1 E2 with and without a heparin dodecasaccharide are presented, revealing two distinct binding modes of the protein to heparan sulfate. The data provide a mechanistic explanation of how APP-like proteins bind to heparan sulfates and how they specifically recognize nonreducing structures of heparan sulfates. Beyond the pathology of Alzheimer’s disease, the members of the amyloid precursor protein (APP) family are essential for neuronal development and cell homeostasis in mammals. APP and its paralogues APP-like protein 1 (APLP1) and APP-like protein 2 (APLP2) contain the highly conserved heparan sulfate (HS) binding domain E2, which effects variousmore » (patho)physiological functions. Here, two crystal structures of the E2 domain of APLP1 are presented in the apo form and in complex with a heparin dodecasaccharide at 2.5 Å resolution. The apo structure of APLP1 E2 revealed an unfolded and hence flexible N-terminal helix αA. The (APLP1 E2){sub 2}–(heparin){sub 2} complex structure revealed two distinct binding modes, with APLP1 E2 explicitly recognizing the heparin terminus but also interacting with a continuous heparin chain. The latter only requires a certain register of the sugar moieties that fits to a positively charged surface patch and contributes to the general heparin-binding capability of APP-family proteins. Terminal binding of APLP1 E2 to heparin specifically involves a structure of the nonreducing end that is very similar to heparanase-processed HS chains. These data reveal a conserved mechanism for the binding of APP-family proteins to HS and imply a specific regulatory role of HS modifications in the biology of APP and APP-like proteins.« less
Blanchette, Cassandra R; Thackeray, Andrea; Perrat, Paola N; Hekimi, Siegfried; Bénard, Claire Y
2017-01-01
The regulation of cell migration is essential to animal development and physiology. Heparan sulfate proteoglycans shape the interactions of morphogens and guidance cues with their respective receptors to elicit appropriate cellular responses. Heparan sulfate proteoglycans consist of a protein core with attached heparan sulfate glycosaminoglycan chains, which are synthesized by glycosyltransferases of the exostosin (EXT) family. Abnormal HS chain synthesis results in pleiotropic consequences, including abnormal development and tumor formation. In humans, mutations in either of the exostosin genes EXT1 and EXT2 lead to osteosarcomas or multiple exostoses. Complete loss of any of the exostosin glycosyltransferases in mouse, fish, flies and worms leads to drastic morphogenetic defects and embryonic lethality. Here we identify and study previously unavailable viable hypomorphic mutations in the two C. elegans exostosin glycosyltransferases genes, rib-1 and rib-2. These partial loss-of-function mutations lead to a severe reduction of HS levels and result in profound but specific developmental defects, including abnormal cell and axonal migrations. We find that the expression pattern of the HS copolymerase is dynamic during embryonic and larval morphogenesis, and is sustained throughout life in specific cell types, consistent with HSPGs playing both developmental and post-developmental roles. Cell-type specific expression of the HS copolymerase shows that HS elongation is required in both the migrating neuron and neighboring cells to coordinate migration guidance. Our findings provide insights into general principles underlying HSPG function in development.
Oshima, Kaori; Haeger, Sarah M.; Hippensteel, Joseph A.; Herson, Paco S.
2017-01-01
Advances in tissue fixation and imaging techniques have yielded increasing appreciation for the glycosaminoglycan-rich endothelial glycocalyx and its in vivo manifestation, the endothelial surface layer (ESL). Pathological loss of the ESL during critical illness promotes local endothelial dysfunction and, consequently, organ injury. Glycosaminoglycan fragments, such as heparan sulfate, are released into the plasma of animals and humans after ESL degradation and have thus served as a biomarker of endothelial injury. The development of state-of-the-art glycomic techniques, however, has revealed that these circulating heparan sulfate fragments are capable of influencing growth factor and other signaling pathways distant to the site of ESL injury. This review summarizes the current state of knowledge concerning the local (i.e. endothelial injury) and systemic (i.e. para- or endocrine) consequences of ESL degradation and identifies opportunities for future, novel investigations. PMID:29199903
Heparan sulfate proteoglycans regulate autophagy in Drosophila.
Reynolds-Peterson, Claire E; Zhao, Na; Xu, Jie; Serman, Taryn M; Xu, Jielin; Selleck, Scott B
2017-08-03
Heparan sulfate-modified proteoglycans (HSPGs) are important regulators of signaling and molecular recognition at the cell surface and in the extracellular space. Disruption of HSPG core proteins, HS-synthesis, or HS-degradation can have profound effects on growth, patterning, and cell survival. The Drosophila neuromuscular junction provides a tractable model for understanding the activities of HSPGs at a synapse that displays developmental and activity-dependent plasticity. Muscle cell-specific knockdown of HS biosynthesis disrupted the organization of a specialized postsynaptic membrane, the subsynaptic reticulum (SSR), and affected the number and morphology of mitochondria. We provide evidence that these changes result from a dysregulation of macroautophagy (hereafter referred to as autophagy). Cellular and molecular markers of autophagy are all consistent with an increase in the levels of autophagy in the absence of normal HS-chain biosynthesis and modification. HS production is also required for normal levels of autophagy in the fat body, the central energy storage and nutritional sensing organ in Drosophila. Genetic mosaic analysis indicates that HS-dependent regulation of autophagy occurs non-cell autonomously, consistent with HSPGs influencing this cellular process via signaling in the extracellular space. These findings demonstrate that HS biosynthesis has important regulatory effects on autophagy and that autophagy is critical for normal assembly of postsynaptic membrane specializations.
Zhang, Fang; Sodroski, Catherine; Cha, Helen; Li, Qisheng; Liang, T Jake
2017-01-01
The signaling molecule and transcriptional regulator SMAD6, which inhibits the transforming growth factor β signaling pathway, is required for infection of hepatocytes by hepatitis C virus (HCV). We investigated the mechanisms by which SMAD6 and another inhibitory SMAD (SMAD7) promote HCV infection in human hepatoma cells and hepatocytes. We infected Huh7 and Huh7.5.1 cells and primary human hepatocytes with Japanese fulminant hepatitis-1 (JFH1) HCV cell culture system (HCVcc). We then measured HCV binding, intracellular levels of HCV RNA, and expression of target genes. We examined HCV entry in HepG2/microRNA (miR) 122/CD81 cells, which support entry and replication of HCV, were transfected these cells with small interfering RNAs targeting inhibitory SMADs to analyze gene expression profiles. Uptake of labeled low-density lipoprotein (LDL) and cholesterol was measured. Cell surface proteins were quantified by flow cytometry. We obtained liver biopsy samples from 69 patients with chronic HCV infection and 19 uninfected individuals (controls) and measured levels of syndecan 1 (SDC1), SMAD7, and SMAD6 messenger RNAs (mRNAs). Small interfering RNA knockdown of SMAD6 blocked the binding and infection of hepatoma cell lines and primary human hepatocytes by HCV, whereas SMAD6 overexpression increased HCV infection. We found levels of mRNAs encoding heparan sulfate proteoglycans (HSPGs), particularly SDC1 mRNA, and cell surface levels of heparan sulfate to be reduced in cells after SMAD6 knockdown. SMAD6 knockdown also reduced transcription of genes encoding lipoprotein and cholesterol uptake receptors, including the LDL receptor (LDLR), the very LDLR, and the scavenger receptor class B member 1 in hepatocytes; knockdown of SMAD6 also inhibited cell uptake of cholesterol and lipoprotein. Overexpression of SMAD6 increased the expression of these genes. Similar effects were observed with knockdown and overexpression of SMAD7. In addition, HCV infection of cells increased the expression of SMAD6, which required the activity of nuclear factor-κB, but not transforming growth factor β. Liver tissues from patients with chronic HCV infection had significantly higher levels of SMAD6, SMAD7, and HSPG mRNAs than controls. In studies of hepatoma cell lines and primary human hepatocytes, we found that infection with HCV leads to activation of nuclear factor-κB, resulting in increased expression of SMAD6 and SMAD7. Up-regulation of SMAD6 and SMAD7 induces the expression of HSPGs, such as SDC1, as well as LDLR, very LDLR, and the scavenger receptor class B member 1, which promote HCV entry and propagation, as well as cellular uptake of cholesterol and lipoprotein. Copyright © 2017 AGA Institute. Published by Elsevier Inc. All rights reserved.
Hammond, Edward; Khurana, Ashwani; Shridhar, Viji; Dredge, Keith
2014-01-01
Heparan sulfate proteoglycans (HSPGs) are an integral and dynamic part of normal tissue architecture at the cell surface and within the extracellular matrix. The modification of HSPGs in the tumor microenvironment is known to result not just in structural but also functional consequences, which significantly impact cancer progression. As substrates for the key enzymes sulfatases and heparanase, the modification of HSPGs is typically characterized by the degradation of heparan sulfate (HS) chains/sulfation patterns via the endo-6-O-sulfatases (Sulf1 and Sulf2) or by heparanase, an endo-glycosidase that cleaves the HS polymers releasing smaller fragments from HSPG complexes. Numerous studies have demonstrated how these enzymes actively influence cancer cell proliferation, signaling, invasion, and metastasis. The activity or expression of these enzymes has been reported to be modified in a variety of cancers. Such observations are consistent with the degradation of normal architecture and basement membranes, which are typically compromised in metastatic disease. Moreover, recent studies elucidating the requirements for these proteins in tumor initiation and progression exemplify their importance in the development and progression of cancer. Thus, as the influence of the tumor microenvironment in cancer progression becomes more apparent, the focus on targeting enzymes that degrade HSPGs highlights one approach to maintain normal tissue architecture, inhibit tumor progression, and block metastasis. This review discusses the role of these enzymes in the context of the tumor microenvironment and their promise as therapeutic targets for the treatment of cancer. PMID:25105093
Role of heparan sulfate in sexually transmitted infections
Tiwari, Vaibhav; Maus, Erika; Sigar, Ira M; Ramsey, Kyle H; Shukla, Deepak
2012-01-01
Cell surface heparan sulfate (HS), a polysaccharide composed of alternating uronic acid and glucosamine residues, represents a common link that many sexually transmitted infections (STIs) require for infection. Variable modifications within the monomeric units of HS chains together with their unique structural conformations generate heterogeneity, which expands the ability of HS to bind a diverse array of host and microbial proteins. Recent advances made in the field of glycobiology have critically enhanced our understanding of HS and its interactions with microbes and their significance in important human diseases. The role of HS has been elaborated for several STIs to include those caused by herpes simplex virus, human immunodeficiency virus, human papillomavirus, and Chlamydia. In addition, gonorrhea, syphilis, and yeast infections are also dependent on the presence of HS on human target cells. Critical steps such as pathogen adhesion or binding to host cells followed by internalization to enhance intracellular survival and possible spread to other cells are mediated by HS. In addition, HS guided cell signaling plays a role in the development of angiogenesis and inflammation associated with many STIs. Past and ongoing investigations are providing new push for the development of HS-mimetics and analogs as novel prevention strategies against many different STIs. This review article summarizes the significance of HS in STIs and describes how emerging new products that target HS can be used to control the spread of STIs. PMID:22773448
Hanoulle, Xavier; Melchior, Aurélie; Sibille, Nathalie; Parent, Benjamin; Denys, Agnès; Wieruszeski, Jean-Michel; Horvath, Dragos; Allain, Fabrice; Lippens, Guy; Landrieu, Isabelle
2007-11-23
The chemotaxis and integrin-mediated adhesion of T lymphocytes triggered by secreted cyclophilin B (CypB) depend on interactions with both cell surface heparan sulfate proteoglycans (HSPG) and the extracellular domain of the CD147 membrane receptor. Here, we use NMR spectroscopy to characterize the interaction of CypB with heparin-derived oligosaccharides. Chemical shift perturbation experiments allowed the precise definition of the heparan sulfate (HS) binding site of CypB. The N-terminal extremity of CypB, which contains a consensus sequence for heparin-binding proteins was modeled on the basis of our experimental NMR data. Because the HS binding site extends toward the CypB catalytic pocket, we measured its peptidyl-prolyl cis-trans isomerase (PPIase) activity in the absence or presence of a HS oligosaccharide toward a CD147-derived peptide. We report the first direct evidence that CypB is enzymatically active on CD147, as it is able to accelerate the cis/trans isomerization of the Asp(179)-Pro(180) bond in a CD147-derived peptide. However, HS binding has no significant influence on this PPIase activity. We thus conclude that the glycanic moiety of HSPG serves as anchor for CypB at the cell surface, and that the signal could be transduced by CypB via its PPIase activity toward CD147.
Grassot, Vincent; Bouchatal, Amel; Da Silva, Anne; Chantepie, Sandrine; Papy-Garcia, Dulce; Maftah, Abderrahman; Gallet, Paul-François; Petit, Jean-Michel
In vitro, extracted muscle satellite cells, called myogenic progenitor cells, can differentiate either in myotubes or preadipocytes, depending on environmental factors and the medium. Transcriptomic analyses on glycosylation genes during satellite cells differentiation into myotubes showed that 31 genes present a significant variation of expression at the early stages of murine myogenic progenitor cells (MPC) differentiation. In the present study, we analyzed the expression of 383 glycosylation related genes during murine MPC differentiation into preadipocytes and compared the data to those previously obtained during their differentiation into myotubes. Fifty-six glycosylation related genes are specifically modified in their expression during early adipogenesis. The variations correspond mainly to: a decrease of N-glycans, and of alpha (2,3) and (2,6) linked sialic acids, and to a high level of heparan sulfates. A high amount of TGF-β1 in extracellular media during early adipogenesis was also observed. It seems that the increases of heparan sulfates and TGF-β1 favor pre-adipogenic differentition of MPC and possibly prevent their myogenic differentiation. Copyright © 2016 International Society of Differentiation. Published by Elsevier B.V. All rights reserved.
Wang, Xiangming; Liu, Jianhong; Zhu, Zhiwen; Ou, Guangshuo
2015-03-15
Directional cell migration is fundamental for neural development, and extracellular factors are pivotal for this process. Heparan sulfate proteoglycans (HSPGs) that carry long chains of differentially modified sugar residues contribute to extracellular matrix; however, the functions of HSPG in guiding cell migration remain elusive. Here, we used the Caenorhabditis elegans mutant pool from the Million Mutation Project and isolated a mutant allele of the heparan sulfate-modifying enzyme glucuronyl C5-epimerase HSE-5. Loss-of-function of this enzyme resulted in defective Q neuroblast migration. We showed that hse-5 controlled Q cell migration in a cell non-autonomous manner. By performing live cell imaging in hse-5 mutant animals, we found that hse-5 controlled initial polarization during Q neuroblast migration. Furthermore, our genetic epistasis analysis demonstrated that lon-2 might act downstream of hse-5. Finally, rescue of the hse-5 mutant phenotype by expression of human and mouse hse-5 homologs suggested a conserved function for this gene in neural development. Taken together, our results indicated that proper HSPG modification in the extracellular matrix by HSE-5 is essential for neuroblast polarity during migration. Copyright © 2015 Elsevier Inc. All rights reserved.
Phan, Anne Q; Lee, Jangwoo; Oei, Michelle; Flath, Craig; Hwe, Caitlyn; Mariano, Rachele; Vu, Tiffany; Shu, Cynthia; Dinh, Andrew; Simkin, Jennifer; Muneoka, Ken; Bryant, Susan V; Gardiner, David M
2015-08-01
Urodele amphibians are unique among adult vertebrates in their ability to regenerate complex body structures after traumatic injury. In salamander regeneration, the cells maintain a memory of their original position and use this positional information to recreate the missing pattern. We used an in vivo gain-of-function assay to determine whether components of the extracellular matrix (ECM) have positional information required to induce formation of new limb pattern during regeneration. We discovered that salamander limb ECM has a position-specific ability to either inhibit regeneration or induce de novo limb structure, and that this difference is dependent on heparan sulfates that are associated with differential expression of heparan sulfate sulfotransferases. We also discovered that an artificial ECM containing only heparan sulfate was sufficient to induce de novo limb pattern in salamander limb regeneration. Finally, ECM from mouse limbs is capable of inducing limb pattern in axolotl blastemas in a position-specific, developmental-stage-specific, and heparan sulfate-dependent manner. This study demonstrates a mechanism for positional information in regeneration and establishes a crucial functional link between salamander regeneration and mammals.
Phan, Anne Q.; Lee, Jangwoo; Oei, Michelle; Flath, Craig; Hwe, Caitlyn; Mariano, Rachele; Vu, Tiffany; Shu, Cynthia; Dinh, Andrew; Simkin, Jennifer; Muneoka, Ken; Bryant, Susan V.
2015-01-01
Abstract Urodele amphibians are unique among adult vertebrates in their ability to regenerate complex body structures after traumatic injury. In salamander regeneration, the cells maintain a memory of their original position and use this positional information to recreate the missing pattern. We used an in vivo gain‐of‐function assay to determine whether components of the extracellular matrix (ECM) have positional information required to induce formation of new limb pattern during regeneration. We discovered that salamander limb ECM has a position‐specific ability to either inhibit regeneration or induce de novo limb structure, and that this difference is dependent on heparan sulfates that are associated with differential expression of heparan sulfate sulfotransferases. We also discovered that an artificial ECM containing only heparan sulfate was sufficient to induce de novo limb pattern in salamander limb regeneration. Finally, ECM from mouse limbs is capable of inducing limb pattern in axolotl blastemas in a position‐specific, developmental‐stage‐specific, and heparan sulfate‐dependent manner. This study demonstrates a mechanism for positional information in regeneration and establishes a crucial functional link between salamander regeneration and mammals. PMID:27499874
Sharthiya, Harsh; Seng, Chanmoly; Van Kuppevelt, T H; Tiwari, Vaibhav; Fornaro, Michele
2017-06-01
The molecular mechanism of herpes simplex virus (HSV) entry and the associated inflammatory response in the nervous system remain poorly understood. Using mouse-derived ex vivo dorsal root ganglia (DRG) explant model and single cell neurons (SCNs), in this study, we provided a visual evidence for the expression of heparan sulfate (HS) and 3-O-sulfated heparan sulfate (3-OS HS) followed by their interactions with HSV-1 glycoprotein B (gB) and glycoprotein D (gD) during cell entry. Upon heparanase treatment of DRG-derived SCN, a significant inhibition of HSV-1 entry was observed suggesting the involvement of HS role during viral entry. Finally, a cytokine array profile generated during HSV-1 infection in DRG explant indicated an enhanced expression of chemokines (LIX, TIMP-2, and M-CSF)-known regulators of HS. Taken together, these results highlight the significance of HS during HSV-1 entry in DRG explant. Further investigation is needed to understand which isoforms of 3-O-sulfotransferase (3-OST)-generated HS contributed during HSV-1 infection and associated cell damage.
Schittny, J C; Timpl, R; Engel, J
1988-10-01
Thin and ultrathin cryosections of mouse cornea were labeled with affinity-purified antibodies directed against either laminin, its central segments (domain 1), the end of its long arm (domain 3), the end of one of its short arms (domain 4), nidogen, or low density heparan sulfate proteoglycan. All basement membrane proteins are detected by indirect immunofluorescence exclusively in the epithelial basement membrane, in Descemet's membrane, and in small amorphous plaques located in the stroma. Immunoelectron microscopy using the protein A-gold technique demonstrated laminin domain 1 and nidogen in a narrow segment of the lamina densa at the junction to the lamina lucida within the epithelial basement membrane. Domain 3 shows three preferred locations at both the cellular and stromal boundaries of the epithelial basement membrane and in its center. Domain 4 is located predominantly in the lamina lucida and the adjacent half of the lamina densa. The low density heparan sulfate proteoglycan is found all across the basement membrane showing a similar uniform distribution as with antibodies against the whole laminin molecule. In Descemet's membrane an even distribution was found with all these antibodies. It is concluded that within the epithelial basement membrane the center of the laminin molecule is located near the lamina densa/lamina lucida junction and that its long arm favors three major orientations. One is close to the cell surface indicating binding to a cell receptor, while the other two are directed to internal matrix structures. The apparent codistribution of laminin domain 1 and nidogen agrees with biochemical evidence that nidogen binds to this domain.
Billings, Paul C; Pacifici, Maurizio
2015-01-01
Heparan sulfate (HS) is a component of cell surface and matrix-associated proteoglycans (HSPGs) that, collectively, play crucial roles in many physiologic processes including cell differentiation, organ morphogenesis and cancer. A key function of HS is to bind and interact with signaling proteins, growth factors, plasma proteins, immune-modulators and other factors. In doing so, the HS chains and HSPGs are able to regulate protein distribution, bio-availability and action on target cells and can also serve as cell surface co-receptors, facilitating ligand-receptor interactions. These proteins contain an HS/heparin-binding domain (HBD) that mediates their association and contacts with HS. HBDs are highly diverse in sequence and predicted structure, contain clusters of basic amino acids (Lys and Arg) and possess an overall net positive charge, most often within a consensus Cardin-Weintraub (CW) motif. Interestingly, other domains and residues are now known to influence protein-HS interactions, as well as interactions with other glycosaminoglycans, such as chondroitin sulfate. In this review, we provide a description and analysis of HBDs in proteins including amphiregulin, fibroblast growth factor family members, heparanase, sclerostin and hedgehog protein family members. We discuss HBD structural and functional features and important roles carried out by other protein domains, and also provide novel conformational insights into the diversity of CW motifs present in Sonic, Indian and Desert hedgehogs. Finally, we review progress in understanding the pathogenesis of a rare pediatric skeletal disorder, Hereditary Multiple Exostoses (HME), characterized by HS deficiency and cartilage tumor formation. Advances in understanding protein-HS interactions will have broad implications for basic biology and translational medicine as well as for the development of HS-based therapeutics.
Inhibition of HSV cell-to-cell spread by lactoferrin and lactoferricin.
Jenssen, Håvard; Sandvik, Kjersti; Andersen, Jeanette H; Hancock, Robert E W; Gutteberg, Tore J
2008-09-01
The milk protein lactoferrin (Lf) has multiple functions, including immune stimulation and antiviral activity towards herpes simplex virus 1 and 2 (HSV-1 and HSV-2); antiviral activity has also been reported for the N-terminal pepsin-derived fragment lactoferricin (Lfcin). The anti-HSV mode of action of Lf and Lfcin is assumed to involve, in part, their interaction with the cell surface glycosaminoglycan heparan sulfate, thereby blocking of viral entry. In this study we investigated the ability of human and bovine Lf and Lfcin to inhibit viral cell-to-cell spread as well as the involvement of cell surface glycosaminoglycans during viral cell-to-cell spread. Lf and Lfcin from both human and bovine origin, inhibited cell-to-cell spread of both HSV-1 and HSV-2. Inhibition of cell-to-cell spread by bovine Lfcin involved cell surface chondroitin sulfate. Based on transmission electron microscopy studies, human Lfcin, like bovine Lfcin, was randomly distributed intracellularly, thus differences in their antiviral activity could not be explained by differences in their distribution. In contrast, the cellular localization of iron-saturated (holo)-Lf appeared to differ from that of apo-Lf, indicating that holo- and apo-Lf may exhibit different antiviral mechanisms.
Reduced Sulfation of Chondroitin Sulfate but Not Heparan Sulfate in Kidneys of Diabetic db/db Mice
Reine, Trine M.; Grøndahl, Frøy; Jenssen, Trond G.; Hadler-Olsen, Elin; Prydz, Kristian
2013-01-01
Heparan sulfate proteoglycans are hypothesized to contribute to the filtration barrier in kidney glomeruli and the glycocalyx of endothelial cells. To investigate potential changes in proteoglycans in diabetic kidney, we isolated glycosaminoglycans from kidney cortex from healthy db/+ and diabetic db/db mice. Disaccharide analysis of chondroitin sulfate revealed a significant decrease in the 4-O-sulfated disaccharides (D0a4) from 65% to 40%, whereas 6-O-sulfated disaccharides (D0a6) were reduced from 11% to 6%, with a corresponding increase in unsulfated disaccharides. In contrast, no structural differences were observed in heparan sulfate. Furthermore, no difference was found in the molar amount of glycosaminoglycans, or in the ratio of hyaluronan/heparan sulfate/chondroitin sulfate. Immunohistochemical staining for the heparan sulfate proteoglycan perlecan was similar in both types of material but reduced staining of 4-O-sulfated chondroitin and dermatan was observed in kidney sections from diabetic mice. In support of this, using qRT-PCR, a 53.5% decrease in the expression level of Chst-11 (chondroitin 4-O sulfotransferase) was demonstrated in diabetic kidney. These results suggest that changes in the sulfation of chondroitin need to be addressed in future studies on proteoglycans and kidney function in diabetes. PMID:23757342
Reduced sulfation of chondroitin sulfate but not heparan sulfate in kidneys of diabetic db/db mice.
Reine, Trine M; Grøndahl, Frøy; Jenssen, Trond G; Hadler-Olsen, Elin; Prydz, Kristian; Kolset, Svein O
2013-08-01
Heparan sulfate proteoglycans are hypothesized to contribute to the filtration barrier in kidney glomeruli and the glycocalyx of endothelial cells. To investigate potential changes in proteoglycans in diabetic kidney, we isolated glycosaminoglycans from kidney cortex from healthy db/+ and diabetic db/db mice. Disaccharide analysis of chondroitin sulfate revealed a significant decrease in the 4-O-sulfated disaccharides (D0a4) from 65% to 40%, whereas 6-O-sulfated disaccharides (D0a6) were reduced from 11% to 6%, with a corresponding increase in unsulfated disaccharides. In contrast, no structural differences were observed in heparan sulfate. Furthermore, no difference was found in the molar amount of glycosaminoglycans, or in the ratio of hyaluronan/heparan sulfate/chondroitin sulfate. Immunohistochemical staining for the heparan sulfate proteoglycan perlecan was similar in both types of material but reduced staining of 4-O-sulfated chondroitin and dermatan was observed in kidney sections from diabetic mice. In support of this, using qRT-PCR, a 53.5% decrease in the expression level of Chst-11 (chondroitin 4-O sulfotransferase) was demonstrated in diabetic kidney. These results suggest that changes in the sulfation of chondroitin need to be addressed in future studies on proteoglycans and kidney function in diabetes.
Jacques, Alexandre; Bleau, Christian; Turbide, Claire; Beauchemin, Nicole; Lamontagne, Lucie
2009-01-01
A rapid antiviral immune response may be related to viral interaction with the host cell leading to activation of macrophages via pattern recognition receptors (PPRs) or specific viral receptors. Carcinoembryonic cell adhesion antigen 1a (CEACAM1a) is the specific receptor for the mouse hepatitis virus (MHV), a coronavirus known to induce acute viral hepatitis in mice. The objective of this study was to understand the mechanisms responsible for the secretion of high-pathogenic MHV3-induced inflammatory cytokines. We report that the induction of the pro-inflammatory cytokines interleukin (IL)-6 and tumour necrosis factor (TNF)-α in peritoneal macrophages does not depend on CEACAM1a, as demonstrated in cells isolated from Ceacam1a−/− mice. The induction of IL-6 and TNF-α production was related rather to the fixation of the spike (S) protein of MHV3 on Toll-like receptor 2 (TLR2) in regions enriched in heparan sulphate and did not rely on viral replication, as demonstrated with denatured S protein and UV-inactivated virus. High levels of IL-6 and TNF-α were produced in livers from infected C57BL/6 mice but not in livers from Tlr2−/− mice. The histopathological observations were correlated with the levels of those inflammatory cytokines. Depending on mouse strain, the viral fixation to heparan sulfate/TLR2 stimulated differently the p38 mitogen-activated protein kinase (MAPK) and nuclear factor (NF)-κB in the induction of IL-6 and TNF-α. These results suggest that TLR2 and heparan sulphate receptors can act as new viral PPRs involved in inflammatory responses. PMID:19740307
Brusilovsky, Michael; Cordoba, Moti; Rosental, Benyamin; Hershkovitz, Oren; Andrake, Mark D.; Pecherskaya, Anna; Einarson, Margret B.; Zhou, Yan; Braiman, Alex
2013-01-01
KIR2DL4 (CD158d) is a distinct member of the killer cell Ig-like receptor (KIR) family in human NK cells that can induce cytokine production and cytolytic activity in resting NK cells. Soluble HLA-G, normally expressed only by fetal-derived trophoblast cells, was reported to be a ligand for KIR2DL4; however, KIR2DL4 expression is not restricted to the placenta and can be found in CD56high subset of peripheral blood NK cells. We demonstrated that KIR2DL4 can interact with alternative ligand(s), expressed by cells of epithelial or fibroblast origin. A genome-wide high-throughput siRNA screen revealed that KIR2DL4 recognition of cells surface ligand(s) is directly regulated by heparan sulfate (HS) glucosamine 3-O-sulfotransferase 3B1 (HS3ST3B1). KIR2DL4 was found to directly interact with HS/heparin, and the D0-domain of KIR2DL4 was essential for this interaction. Accordingly, exogenous HS/heparin can regulate cytokine production by KIR2DL4-expressing NK cells and HEK293T cells (HEK293T-2DL4) and induces differential localization of KIR2DL4 to rab5+ and rab7+ endosomes, thus leading to down-regulation of cytokine production and degradation of the receptor. Furthermore, we showed that intimate interaction of syndecan-4 (SDC4) HS Proteo-Glycan (HSPG) and KIR2DL4 directly affects receptor endocytosis and membrane trafficking. PMID:24127555
Hirano, Kazumi; Sasaki, Norihiko; Ichimiya, Tomomi; Miura, Taichi; Van Kuppevelt, Toin H; Nishihara, Shoko
2012-01-01
Maintenance of self-renewal and pluripotency in mouse embryonic stem cells (mESCs) is regulated by the balance between several extrinsic signaling pathways. Recently, we demonstrated that heparan sulfate (HS) chains play important roles in the maintenance and differentiation of mESCs by regulating extrinsic signaling. Sulfated HS structures are modified by various sulfotransferases during development. However, the significance of specific HS structures during development remains unclear. Here, we show that 3-O-sulfated HS structures synthesized by HS 3-O-sulfotransferases (3OSTs) and recognized by the antibody HS4C3 increase during differentiation of mESCs. Furthermore, expression of Fas on the cell surface of the differentiated cells also increased. Overexpression of the HS4C3-binding epitope in mESCs induced apoptosis and spontaneous differentiation even in the presence of LIF and serum. These data showed that the HS4C3-binding epitope was required for differentiation of mESCs. Up-regulation of the HS4C3-binding epitope resulted in the recruitment of Fas from the cytoplasm to lipid rafts on the cell surface followed by activation of Fas signaling. Indeed, the HS4C3-binding epitope interacted with a region that included the heparin-binding domain (KLRRRVH) of Fas. Reduced self-renewal capability in cells overexpressing 3OST resulted from the degradation of Nanog by activated caspase-3, which is downstream of Fas signaling, and was rescued by the inhibition of Fas signaling. We also found that knockdown of 3OST and inhibition of Fas signaling reduced the potential for differentiation into the three germ layers during embryoid body formation. This is the first demonstration that activation of Fas signaling is mediated by an increase in the HS4C3-binding epitope and indicates a novel signaling pathway for differentiation in mESCs.
Hirano, Kazumi; Sasaki, Norihiko; Ichimiya, Tomomi; Miura, Taichi; Van Kuppevelt, Toin H.; Nishihara, Shoko
2012-01-01
Maintenance of self-renewal and pluripotency in mouse embryonic stem cells (mESCs) is regulated by the balance between several extrinsic signaling pathways. Recently, we demonstrated that heparan sulfate (HS) chains play important roles in the maintenance and differentiation of mESCs by regulating extrinsic signaling. Sulfated HS structures are modified by various sulfotransferases during development. However, the significance of specific HS structures during development remains unclear. Here, we show that 3-O-sulfated HS structures synthesized by HS 3-O-sulfotransferases (3OSTs) and recognized by the antibody HS4C3 increase during differentiation of mESCs. Furthermore, expression of Fas on the cell surface of the differentiated cells also increased. Overexpression of the HS4C3-binding epitope in mESCs induced apoptosis and spontaneous differentiation even in the presence of LIF and serum. These data showed that the HS4C3-binding epitope was required for differentiation of mESCs. Up-regulation of the HS4C3-binding epitope resulted in the recruitment of Fas from the cytoplasm to lipid rafts on the cell surface followed by activation of Fas signaling. Indeed, the HS4C3-binding epitope interacted with a region that included the heparin-binding domain (KLRRRVH) of Fas. Reduced self-renewal capability in cells overexpressing 3OST resulted from the degradation of Nanog by activated caspase-3, which is downstream of Fas signaling, and was rescued by the inhibition of Fas signaling. We also found that knockdown of 3OST and inhibition of Fas signaling reduced the potential for differentiation into the three germ layers during embryoid body formation. This is the first demonstration that activation of Fas signaling is mediated by an increase in the HS4C3-binding epitope and indicates a novel signaling pathway for differentiation in mESCs. PMID:22916262
Usage of heparan sulfate, integrins, and FAK in HPV16 infection
Abban, Cynthia Y.; Meneses, Patricio I.
2010-01-01
Human Papillomavirus Type 16 (HPV16) is the major causative agent of cervical cancer. Studies regarding the early binding and signaling molecules that play a significant role in infection are still lacking. The current study analyses the role of heparan sulfate, integrins, and the signaling molecule FAK in HPV16 infection of human adult keratinocytes cell line (HaCaTs). Our data demonstrate that infection requires the binding of viral particles to heparan sulfate followed by activation of focal adhesion kinase through an integrin. Infections were reduced in the presence of the FAK inhibitor, TAE226. TAE226 was observed to inhibit viral entry to the early endosome a known infectious route. These findings suggest that FAK can serve as a novel target for antiviral therapy. PMID:20441998
Chan, Wai Kit; Howe, Katherine; Clegg, James M.; Guimond, Scott E.; Price, David J.; Turnbull, Jeremy E.; Pratt, Thomas
2015-01-01
Heparan sulfate (HS) is a linear carbohydrate composed of polymerized uronate-glucosamine disaccharide units that decorates cell surface and secreted glycoproteins in the extracellular matrix. In mammals HS is subjected to differential sulfation by fifteen different heparan sulfotransferase (HST) enzymes of which Hs2st uniquely catalyzes the sulfation of the 2-O position of the uronate in HS. HS sulfation is postulated to be important for regulation of signaling pathways by facilitating the interaction of HS with signaling proteins including those of the Fibroblast Growth Factor (Fgf) family which signal through phosphorylation of extracellular signal-regulated kinases Erk1/2. In the developing mouse telencephalon Fgf2 signaling regulates proliferation and neurogenesis. Loss of Hs2st function phenocopies the thinned cerebral cortex of mutant mice in which Fgf2 or Erk1/2 function are abrogated, suggesting the hypothesis that 2-O-sulfated HS structures play a specific role in Fgf2/Erk signaling pathway in this context in vivo. This study investigated the molecular role of 2-O sulfation in Fgf2/Erk signaling in the developing telencephalic midline midway through mouse embryogenesis at E12.5. We examined the expression of Hs2st, Fgf2, and Erk1/2 activity in wild-type and Hs2st-/- mice. We found that Hs2st is expressed at high levels at the midline correlating with high levels of Erk1/2 activation and Erk1/2 activation was drastically reduced in the Hs2st-/- mutant at the rostral telencephalic midline. We also found that 2-O sulfation is specifically required for the binding of Fgf2 protein to Fgfr1, its major cell-surface receptor at the rostral telencephalic midline. We conclude that 2-O sulfated HS structures generated by Hs2st are needed to form productive signaling complexes between HS, Fgf2 and Fgfr1 that activate Erk1/2 at the midline. Overall, our data suggest the interesting possibility that differential expression of Hs2st targets the rostral telencephalic midline for high levels of Erk signaling by increasing the sensitivity of cells to an Fgf2 signal that is rather more widespread. PMID:26075383
Fernández-Vega, Iván; García-Suárez, Olivia; García, Beatriz; Crespo, Ainara; Astudillo, Aurora; Quirós, Luis M
2015-10-20
Heparan sulfate proteoglycans (HSPGs) are complex molecules involved in the growth, invasion and metastatic properties of cancerous cells. This study analyses the alterations in the expression patterns of these molecules in right sided colorectal cancer (CRC), both metastatic and non-metastatic. Twenty right sided CRCs were studied. A transcriptomic approach was used, employing qPCR to analyze both the expression of the enzymes involved in heparan sulfate (HS) chains biosynthesis, as well as the proteoglycan core proteins. Since some of these proteoglycans can also carry chondroitin sulfate (CS) chains, we include the study of the genes involved in the biosynthesis of these glycosaminoglycans. Immunohistochemical techniques were also used to analyze tissue expression of particular genes showing significant expression differences, of potential interest. Changes in proteoglycan core proteins differ depending on their location; those located intracellularly or in the extracellular matrix show very similar alteration patterns, while those located on the cell surface vary greatly depending on the nature of the tumor: glypicans 1, 3, 6 and betaglycan are affected in the non-metastatic tumors, whereas in the metastatic, only glypican-1 and syndecan-1 are modified, the latter showing opposing alterations in levels of RNA and of protein, suggesting post-transcriptional regulation in these tumors. Furthermore, in non-metastatic tumors, polymerization of glycosaminoglycan chains is modified, particularly affecting the synthesis of the tetrasaccharide linker and the initiation and elongation of CS chains, HS chains being less affected. Regarding the enzymes responsible for the modificaton of the HS chains, alterations were only found in non-metastatic tumors, affecting N-sulfation and the isoforms HS6ST1, HS3ST3B and HS3ST5. In contrast, synthesis of the CS chains suggests changes in epimerization and sulfation of the C4 and C2 in both types of tumor. Right sided CRCs show alterations in the expression of HSPGs, including the expression of the cell surface core proteins, many glycosiltransferases and some enzymes that modify the HS chains depending on the metastatic nature of the tumor, resulting more affected in non-metastatic ones. However, matrix proteoglycans and enzymes involved in CS fine structure synthesis are extensively modified independetly of the presence of lymph node metastasis.
Rees, Martin D; Pattison, David I; Davies, Michael J
2005-10-01
Activated phagocytes release the haem enzyme MPO (myeloperoxidase) and produce superoxide radicals and H2O2 via an oxidative burst. MPO uses H2O2 and Cl- to form HOCl, the physiological mixture of hypochlorous acid and its anion present at pH 7.4. As MPO binds to glycosaminoglycans, oxidation of extracellular matrix and cell surfaces by HOCl may be localized to these materials. However, the reactions of HOCl with glycosaminoglycans are poorly characterized. The GlcNAc (N-acetylglucosamine), GlcNSO3 (glucosamine-N-sulphate) and GlcNH2 [(N-unsubstituted) glucosamine] residues of heparan sulphate are potential targets for HOCl. It is shown here that HOCl reacts with each of these residues to generate N-chloro derivatives, and the absolute rate constants for these reactions have been determined. Reaction at GlcNH2 residues yields chloramines and, subsequently, dichloramines with markedly slower rates, k2 approximately 3.1x10(5) and 9 M(-1) x s(-1) (at 37 degrees C) respectively. Reaction at GlcNSO3 and GlcNAc residues yields N-chlorosulphonamides and chloramides with k2 approximately 0.05 and 0.01 M(-1) x s(-1) (at 37 degrees C) respectively. The corresponding monosaccharides display a similar pattern of reactivity. Decay of the polymer-derived chloramines, N-chlorosulphonamides and chloramides is slow at 37 degrees C and does not result in major structural changes. In contrast, dichloramine decay is rapid at 37 degrees C and results in fragmentation of the polymer backbone. Computational modelling of the reaction of HOCl with heparan sulphate proteoglycans (glypican-1 and perlecan) predicts that the GlcNH2 residues of heparan sulphate are major sites of attack. These results suggest that HOCl may be an important mediator of damage to glycosaminoglycans and proteoglycans at inflammatory foci.
Rees, Martin D.; Pattison, David I.; Davies, Michael J.
2005-01-01
Activated phagocytes release the haem enzyme MPO (myeloperoxidase) and produce superoxide radicals and H2O2 via an oxidative burst. MPO uses H2O2 and Cl− to form HOCl, the physiological mixture of hypochlorous acid and its anion present at pH 7.4. As MPO binds to glycosaminoglycans, oxidation of extracellular matrix and cell surfaces by HOCl may be localized to these materials. However, the reactions of HOCl with glycosaminoglycans are poorly characterized. The GlcNAc (N-acetylglucosamine), GlcNSO3 (glucosamine-N-sulphate) and GlcNH2 [(N-unsubstituted) glucosamine] residues of heparan sulphate are potential targets for HOCl. It is shown here that HOCl reacts with each of these residues to generate N-chloro derivatives, and the absolute rate constants for these reactions have been determined. Reaction at GlcNH2 residues yields chloramines and, subsequently, dichloramines with markedly slower rates, k2∼3.1×105 and 9 M−1·s−1 (at 37 °C) respectively. Reaction at GlcNSO3 and GlcNAc residues yields N-chlorosulphonamides and chloramides with k2∼0.05 and 0.01 M−1·s−1 (at 37 °C) respectively. The corresponding monosaccharides display a similar pattern of reactivity. Decay of the polymer-derived chloramines, N-chlorosulphonamides and chloramides is slow at 37 °C and does not result in major structural changes. In contrast, dichloramine decay is rapid at 37 °C and results in fragmentation of the polymer backbone. Computational modelling of the reaction of HOCl with heparan sulphate proteoglycans (glypican-1 and perlecan) predicts that the GlcNH2 residues of heparan sulphate are major sites of attack. These results suggest that HOCl may be an important mediator of damage to glycosaminoglycans and proteoglycans at inflammatory foci. PMID:15932347
Horiguchi, Ikki; Urabe, Yusuke; Kimura, Keiichi; Sakai, Yasuyuki
2018-01-01
Pluripotent stem cells (PSCs) are one of the promising cell sources for tissue engineering and drug screening. However, mass production of induced pluripotent stem cells (iPSCs) is still developing. Especially, a huge amount of culture medium usage causes expensive cost in the mass production process. In this report, we reduced culture medium usage by extending interval of changing culture medium. In parallel, we also increased glucose concentration and supplied heparan sulfate to avoid depletion of glucose and bFGF, respectively. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) analyses showed that reducing medium change frequency increased differentiation marker expressions but high glucose concentration downregulated these expressions. In contrast, heparan sulfate did not prevent differentiation marker expressions. According to analyses of growth rate, cell growth with extended medium change interval was decreased in later stage of log growth phase despite the existence of high glucose concentration and heparan sulfate. This result and culturing iPSCs with lactate showed that the accumulation of excreted lactate decreased the growth rate regardless of pH control. Conclusively, these experiments show that adding glucose and removing lactate are important to expand iPSCs with reduced culture medium usage. This knowledge should be useful to design economical iPSC mass production and differentiation system. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.
Lin, Liang-Tzung; Chen, Ting-Ying; Chung, Chueh-Yao; Noyce, Ryan S; Grindley, T Bruce; McCormick, Craig; Lin, Ta-Chen; Wang, Guey-Horng; Lin, Chun-Ching; Richardson, Christopher D
2011-05-01
Herpes simplex virus 1 (HSV-1) is a common human pathogen that causes lifelong latent infection of sensory neurons. Non-nucleoside inhibitors that can limit HSV-1 recurrence are particularly useful in treating immunocompromised individuals or cases of emerging acyclovir-resistant strains of herpesvirus. We report that chebulagic acid (CHLA) and punicalagin (PUG), two hydrolyzable tannins isolated from the dried fruits of Terminalia chebula Retz. (Combretaceae), inhibit HSV-1 entry at noncytotoxic doses in A549 human lung cells. Experiments revealed that both tannins targeted and inactivated HSV-1 viral particles and could prevent binding, penetration, and cell-to-cell spread, as well as secondary infection. The antiviral effect from either of the tannins was not associated with induction of type I interferon-mediated responses, nor was pretreatment of the host cell protective against HSV-1. Their inhibitory activities targeted HSV-1 glycoproteins since both natural compounds were able to block polykaryocyte formation mediated by expression of recombinant viral glycoproteins involved in attachment and membrane fusion. Our results indicated that CHLA and PUG blocked interactions between cell surface glycosaminoglycans and HSV-1 glycoproteins. Furthermore, the antiviral activities from the two tannins were significantly diminished in mutant cell lines unable to produce heparan sulfate and chondroitin sulfate and could be rescued upon reconstitution of heparan sulfate biosynthesis. We suggest that the hydrolyzable tannins CHLA and PUG may be useful as competitors for glycosaminoglycans in the management of HSV-1 infections and that they may help reduce the risk for development of viral drug resistance during therapy with nucleoside analogues.
Lin, Liang-Tzung; Chen, Ting-Ying; Chung, Chueh-Yao; Noyce, Ryan S.; Grindley, T. Bruce; McCormick, Craig; Lin, Ta-Chen; Wang, Guey-Horng; Lin, Chun-Ching; Richardson, Christopher D.
2011-01-01
Herpes simplex virus 1 (HSV-1) is a common human pathogen that causes lifelong latent infection of sensory neurons. Non-nucleoside inhibitors that can limit HSV-1 recurrence are particularly useful in treating immunocompromised individuals or cases of emerging acyclovir-resistant strains of herpesvirus. We report that chebulagic acid (CHLA) and punicalagin (PUG), two hydrolyzable tannins isolated from the dried fruits of Terminalia chebula Retz. (Combretaceae), inhibit HSV-1 entry at noncytotoxic doses in A549 human lung cells. Experiments revealed that both tannins targeted and inactivated HSV-1 viral particles and could prevent binding, penetration, and cell-to-cell spread, as well as secondary infection. The antiviral effect from either of the tannins was not associated with induction of type I interferon-mediated responses, nor was pretreatment of the host cell protective against HSV-1. Their inhibitory activities targeted HSV-1 glycoproteins since both natural compounds were able to block polykaryocyte formation mediated by expression of recombinant viral glycoproteins involved in attachment and membrane fusion. Our results indicated that CHLA and PUG blocked interactions between cell surface glycosaminoglycans and HSV-1 glycoproteins. Furthermore, the antiviral activities from the two tannins were significantly diminished in mutant cell lines unable to produce heparan sulfate and chondroitin sulfate and could be rescued upon reconstitution of heparan sulfate biosynthesis. We suggest that the hydrolyzable tannins CHLA and PUG may be useful as competitors for glycosaminoglycans in the management of HSV-1 infections and that they may help reduce the risk for development of viral drug resistance during therapy with nucleoside analogues. PMID:21307190
Yadin, David A.; Robertson, Ian B.; McNaught-Davis, Joanne; Evans, Paul; Stoddart, David; Handford, Penny A.; Jensen, Sacha A.; Redfield, Christina
2013-01-01
Summary The human extracellular matrix glycoprotein fibrillin-1 is the primary component of the 10- to 12-nm-diameter microfibrils, which perform key structural and regulatory roles in connective tissues. Relatively little is known about the molecular mechanisms of fibrillin assembly into microfibrils. Studies using recombinant fibrillin fragments indicate that an interaction between the N- and C-terminal regions drives head-to-tail assembly. Here, we present the structure of a fibrillin N-terminal fragment comprising the fibrillin unique N-terminal (FUN) and the first three epidermal growth factor (EGF)-like domains (FUN-EGF3). Two rod-like domain pairs are separated by a short, flexible linker between the EGF1 and EGF2 domains. We also show that the binding site for the C-terminal region spans multiple domains and overlaps with a heparin interaction site. These data suggest that heparan sulfate may sequester fibrillin at the cell surface via FUN-EGF3 prior to aggregation of the C terminus, thereby regulating microfibril assembly. PMID:24035709
Mechanisms of Heparanase Inhibitors in Cancer Therapy
Heyman, Benjamin; Yang, Yiping
2016-01-01
Heparanase is an endo-β-D-glucuronidase capable of cleaving heparan sulfate (HS) side chains contributing to break down of the extracellular matrix. Increased expression of heparanase has been found in numerous malignancies, and is associated with a poor prognosis. It has generated significant interest as a potential anti-neoplastic target because of the multiple roles it plays in tumor growth and metastasis. The pro-tumorigenic effects of heparanase are enhanced by the release of HS side chains, with subsequent increase in bioactive fragments and increased cytokine levels; both promoting tumor invasion, angiogenesis and metastasis. Preclinical experiments have shown heparanase inhibitors to substantially reduce tumor growth and metastasis leading to clinical trials with heparan sulfate mimetics. In this review we will examine heparanase’s role in tumor biology, its interaction with heparan surface proteoglycans, specifically syndecan-1; as well as the mechanism of action for heparanase inhibitors developed as anti-neoplastic therapeutics. PMID:27576132
Favretto, M E; Krieg, A; Schubert, S; Schubert, U S; Brock, R
2015-07-10
Polymer-based gene delivery systems have enormous potential in biomedicine, but their efficiency is often limited by poor biocompatibility. Poly(methacrylate)s (PMAs) are an interesting class of polymers which allow to explore structure-activity relationships of polymer functionalities for polyplex formation in oligonucleotide delivery. Here, we synthesized and tested a library of PMA polymers, containing functional groups contributing to the different steps of gene delivery, from oligonucleotide complexation to cellular internalization and endosomal escape. By variation of the molar ratios of the individual building blocks, the physicochemical properties of the polymers and polyplexes were fine-tuned to reduce toxicity as well as to increase activity of the polyplexes. To further enhance transfection efficiency, a cell-penetrating peptide (CPP)-like functionality was introduced on the polymeric backbone. With the ability to synthesize large libraries of polymers in parallel we also developed a workflow for a mid-to-high throughput screening, focusing first on safety parameters that are accessible by high-throughput approaches such as blood compatibility and toxicity towards host cells and only at a later stage on more laborious tests for the ability to deliver oligonucleotides. To arrive at a better understanding of the molecular basis of activity, furthermore, the effect of the presence of heparan sulfates on the surface of host cells was assessed and the mechanism of cell entry and intracellular trafficking investigated for those polymers that showed a suitable pharmacological profile. Following endocytic uptake, rapid endosomal release occurred. Interestingly, the presence of heparan sulfates on the cell surface had a negative impact on the activity of those polyplexes that were sensitive to decomplexation by heparin in solution. In summary, the screening approach identified two polymers, which form polyplexes with high stability and transfection capacity exceeding the one of poly(ethylene imine) also in the presence of serum. Copyright © 2015 Elsevier B.V. All rights reserved.
Vanpouille, Christophe; Denys, Agnès; Carpentier, Mathieu; Pakula, Rachel; Mazurier, Joël; Allain, Fabrice
2004-09-01
Cyclophilin B (CyPB) is a heparin-binding protein first identified as a receptor for cyclosporin A. In previous studies, we reported that CyPB triggers chemotaxis and integrin-mediated adhesion of T-lymphocytes by way of interaction with two types of binding sites. The first site corresponds to a signalling receptor; the second site has been identified as heparan sulphate (HS) and appears crucial to induce cell adhesion. Characterization of the HS-binding unit is critical to understand the requirement of HS in pro-adhesive activity of CyPB. By using a strategy based on gel mobility shift assays with fluorophore-labelled oligosaccharides, we demonstrated that the minimal heparin unit required for efficient binding of CyPB is an octasaccharide. The mutants CyPB(KKK-) [where KKK- refers to the substitutions K3A(Lys3-->Ala)/K4A/K5A] and CyPB(DeltaYFD) (where Tyr14-Phe-Asp16 has been deleted) failed to interact with octasaccharides, confirming that the Y14FD16 and K3KK5 clusters are required for CyPB binding. Molecular modelling revealed that both clusters are spatially arranged so that they may act synergistically to form a binding site for the octasaccharide. We then demonstrated that heparin-derived octasaccharides and higher degree of polymerization oligosaccharides inhibited the interaction between CyPB and fluorophore-labelled HS chains purified from T-lymphocytes, and strongly reduced the HS-dependent pro-adhesive activity of CyPB. However, oligosaccharides or heparin were unable to restore adhesion of heparinase-treated T-lymphocytes, indicating that HS has to be present on the cell membrane to support the pro-adhesive activity of CyPB. Altogether, these results demonstrate that the octasaccharide is likely to be the minimal length unit required for efficient binding of CyPB to cell surface HS and consequent HS-dependent cell responses.
2004-01-01
Cyclophilin B (CyPB) is a heparin-binding protein first identified as a receptor for cyclosporin A. In previous studies, we reported that CyPB triggers chemotaxis and integrin-mediated adhesion of T-lymphocytes by way of interaction with two types of binding sites. The first site corresponds to a signalling receptor; the second site has been identified as heparan sulphate (HS) and appears crucial to induce cell adhesion. Characterization of the HS-binding unit is critical to understand the requirement of HS in pro-adhesive activity of CyPB. By using a strategy based on gel mobility shift assays with fluorophore-labelled oligosaccharides, we demonstrated that the minimal heparin unit required for efficient binding of CyPB is an octasaccharide. The mutants CyPBKKK− [where KKK− refers to the substitutions K3A(Lys3→Ala)/K4A/K5A] and CyPBΔYFD (where Tyr14-Phe-Asp16 has been deleted) failed to interact with octasaccharides, confirming that the Y14FD16 and K3KK5 clusters are required for CyPB binding. Molecular modelling revealed that both clusters are spatially arranged so that they may act synergistically to form a binding site for the octasaccharide. We then demonstrated that heparin-derived octasaccharides and higher degree of polymerization oligosaccharides inhibited the interaction between CyPB and fluorophore-labelled HS chains purified from T-lymphocytes, and strongly reduced the HS-dependent pro-adhesive activity of CyPB. However, oligosaccharides or heparin were unable to restore adhesion of heparinase-treated T-lymphocytes, indicating that HS has to be present on the cell membrane to support the pro-adhesive activity of CyPB. Altogether, these results demonstrate that the octasaccharide is likely to be the minimal length unit required for efficient binding of CyPB to cell surface HS and consequent HS-dependent cell responses. PMID:15109301
Interaction of Human Tumor Viruses with Host Cell Surface Receptors and Cell Entry
Schäfer, Georgia; Blumenthal, Melissa J.; Katz, Arieh A.
2015-01-01
Currently, seven viruses, namely Epstein-Barr virus (EBV), Kaposi’s sarcoma-associated herpes virus (KSHV), high-risk human papillomaviruses (HPVs), Merkel cell polyomavirus (MCPyV), hepatitis B virus (HBV), hepatitis C virus (HCV) and human T cell lymphotropic virus type 1 (HTLV-1), have been described to be consistently associated with different types of human cancer. These oncogenic viruses belong to distinct viral families, display diverse cell tropism and cause different malignancies. A key to their pathogenicity is attachment to the host cell and entry in order to replicate and complete their life cycle. Interaction with the host cell during viral entry is characterized by a sequence of events, involving viral envelope and/or capsid molecules as well as cellular entry factors that are critical in target cell recognition, thereby determining cell tropism. Most oncogenic viruses initially attach to cell surface heparan sulfate proteoglycans, followed by conformational change and transfer of the viral particle to secondary high-affinity cell- and virus-specific receptors. This review summarizes the current knowledge of the host cell surface factors and molecular mechanisms underlying oncogenic virus binding and uptake by their cognate host cell(s) with the aim to provide a concise overview of potential target molecules for prevention and/or treatment of oncogenic virus infection. PMID:26008702
The Heparan and Heparin Metabolism Pathway is Involved in Regulation of Fatty Acid Composition
USDA-ARS?s Scientific Manuscript database
Six genes involved in the heparan sulfate and heparin metabolism pathway, DSEL (dermatan sulfate epimerase-like), EXTL1 (exostoses (multiple)-like 1), HS6ST1 (heparan sulfate 6-O-sulfotransferase 1), HS6ST3 (heparan sulfate 6-O-sulfotransferase 3), NDST3 (N-deacetylase/N-sulfotransferase (heparan gl...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Roehrig, John T., E-mail: jtr1@cdc.gov; Butrapet, Siritorn; Liss, Nathan M.
Using an infectious cDNA clone we engineered seven mutations in the putative heparan sulfate- and receptor-binding motifs of the envelope protein of dengue virus serotype 2, strain 16681. Four mutant viruses, KK122/123EE, E202K, G304K, and KKK305/307/310EEE, were recovered following transfection of C6/36 cells. A fifth mutant, KK291/295EE, was recovered from C6/36 cells with a compensatory E295V mutation. All mutants grew in and mediated fusion of virus-infected C6/36 cells, but three of the mutants, KK122/123EE, E202K, G304K, did not grow in Vero cells without further modification. Two Vero cell lethal mutants, KK291/295EV and KKK307/307/310EEE, failed to replicate in DC-SIGN-transformed Raji cellsmore » and did not react with monoclonal antibodies known to block DENV attachment to Vero cells. Additionally, both mutants were unable to initiate negative-strand vRNA synthesis in Vero cells by 72 h post-infection, suggesting that the replication block occurred prior to virus-mediated membrane fusion. - Highlights: • Heparan sulfate- and receptor-binding motifs of DENV2 envelope protein were mutated. • Four mutant viruses were isolated—all could fuse C6/36 cells. • Two of these mutants were lethal in Vero cells without further modification. • Lethal mutations were KK291/295EV and KKK305/307/310EEE. • Cell attachment was implicated as the replication block for both mutants.« less
Toh, Yi-Chin; Voldman, Joel
2011-01-01
Shear stress is a ubiquitous environmental cue experienced by stem cells when they are being differentiated or expanded in perfusion cultures. However, its role in modulating self-renewing stem cell phenotypes is unclear, since shear is usually only studied in the context of cardiovascular differentiation. We used a multiplex microfluidic array, which overcomes the limitations of macroperfusion systems in shear application throughput and precision, to initiate a comprehensive, quantitative study of shear effects on self-renewing mouse embryonic stem cells (mESCs), where shear stresses varying by >1000 times (0.016–16 dyn/cm2) are applied simultaneously. When compared with static controls in the presence or absence of a saturated soluble environment (i.e., mESC-conditioned medium), we ascertained that flow-induced shear stress specifically up-regulates the epiblast marker Fgf5. Epiblast-state transition in mESCs involves heparan sulfate proteoglycans (HSPGs), which have also been shown to transduce shear stress in endothelial cells. By disrupting (with sulfation inhibitors and heparinase) and partially reconstituting (with heparin) HSPG function, we show that mESCs also mechanically sense shear stress via HSPGs to modulate Fgf5 expression. This study demonstrates that self-renewing mESCs possess the molecular machinery to sense shear stress and provides quantitative shear application benchmarks for future scalable stem cell culture systems.—Toh, Y.-C., Voldman, J. Fluid shear stress primes mouse embryonic stem cells for differentiation in a self-renewing environment via heparan sulfate proteoglycans transduction. PMID:21183594
Zhang, Rui; Cao, Peijuan; Yang, Zhongzhou; Wang, Zhenzhen; Wu, Jiu-Lin; Chen, Yan; Pan, Yi
2015-01-01
Glycosaminoglycans are important regulators of multiple signaling pathways. As a major constituent of the heart extracellular matrix, glycosaminoglycans are implicated in cardiac morphogenesis through interactions with different signaling morphogens. Ext1 is a glycosyltransferase responsible for heparan sulfate synthesis. Here, we evaluate the function of Ext1 in heart development by analyzing Ext1 hypomorphic mutant and conditional knockout mice. Outflow tract alignment is sensitive to the dosage of Ext1. Deletion of Ext1 in the mesoderm induces a cardiac phenotype similar to that of a mutant with conditional deletion of UDP-glucose dehydrogenase, a key enzyme responsible for synthesis of all glycosaminoglycans. The outflow tract defect in conditional Ext1 knockout(Ext1f/f:Mesp1Cre) mice is attributable to the reduced contribution of second heart field and neural crest cells. Ext1 deletion leads to downregulation of FGF signaling in the pharyngeal mesoderm. Exogenous FGF8 ameliorates the defects in the outflow tract and pharyngeal explants. In addition, Ext1 expression in second heart field and neural crest cells is required for outflow tract remodeling. Our results collectively indicate that Ext1 is crucial for outflow tract formation in distinct progenitor cells, and heparan sulfate modulates FGF signaling during early heart development.
Characteristics of Mitochondrial Transformation into Human Cells
Kesner, E. E.; Saada-Reich, A.; Lorberboum-Galski, H.
2016-01-01
Mitochondria can be incorporated into mammalian cells by simple co-incubation of isolated mitochondria with cells, without the need of transfection reagents or any other type of intervention. This phenomenon was termed mitochondrial transformation, and although it was discovered in 1982, currently little is known regarding its mechanism(s). Here we demonstrate that mitochondria can be transformed into recipient cells very quickly, and co-localize with endogenous mitochondria. The isolated mitochondria interact directly with cells, which engulf the mitochondria with cellular extensions in a way, which may suggest the involvement of macropinocytosis or macropinocytosis-like mechanisms in mitochondrial transformation. Indeed, macropinocytosis inhibitors but not clathrin-mediated endocytosis inhibition-treatments, blocks mitochondria transformation. The integrity of the mitochondrial outer membrane and its proteins is essential for the transformation of the mitochondria into cells; cells can distinguish mitochondria from similar particles and transform only intact mitochondria. Mitochondrial transformation is blocked in the presence of the heparan sulfate molecules pentosan polysulfate and heparin, which indicate crucial involvement of cellular heparan sulfate proteoglycans in the mitochondrial transformation process. PMID:27184109
Surface glycosaminoglycans mediate adherence between HeLa cells and Lactobacillus salivarius Lv72.
Martín, Rebeca; Martín, Carla; Escobedo, Susana; Suárez, Juan E; Quirós, Luis M
2013-09-17
The adhesion of lactobacilli to the vaginal surface is of paramount importance to develop their probiotic functions. For this reason, the role of HeLa cell surface proteoglycans in the attachment of Lactobacillus salivarius Lv72, a mutualistic strain of vaginal origin, was investigated. Incubation of cultures with a variety of glycosaminoglycans (chondroitin sulfate A and C, heparin and heparan sulfate) resulted in marked binding interference. However, no single glycosaminoglycan was able to completely abolish cell binding, the sum of all having an additive effect that suggests cooperation between them and recognition of specific adhesins on the bacterial surface. In contrast, chondroitin sulfate B enhanced cell to cell attachment, showing the relevance of the stereochemistry of the uronic acid and the sulfation pattern on binding. Elimination of the HeLa surface glycosaminoglycans with lyases also resulted in severe adherence impairment. Advantage was taken of the Lactobacillus-glycosaminoglycans interaction to identify an adhesin from the bacterial surface. This protein, identify as a soluble binding protein of an ABC transporter system (OppA) by MALDI-TOF/(MS), was overproduced in Escherichia coli, purified and shown to interfere with L. salivarius Lv72 adhesion to HeLa cells. These data suggest that glycosaminoglycans play a fundamental role in attachment of mutualistic bacteria to the epithelium that lines the cavities where the normal microbiota thrives, OppA being a bacterial adhesin involved in the process.
Megakaryocytopoiesis in Stem Cell Transplantation
1997-10-01
megakaryocyte production by at least 3-fold by a still unknown mechanism. We were able to rule out any role of stromal concentrations of thrombopoietin, interleukins 3 and 6, stem cell factor and heparan sulfates on this enhancing effect.
Préchoux, Aurélie; Halimi, Célia; Simorre, Jean-Pierre; Lortat-Jacob, Hugues; Laguri, Cédric
2015-04-17
Heparan sulfate (HS), a complex polysaccharide of the cell surface, is endowed with the remarkable ability to bind numerous proteins and, as such, regulates a large variety of biological processes. Protein binding depends on HS structure; however, in the absence of a template driving its biosynthesis, the mechanism by which protein binding sequences are assembled remains poorly known. Here, we developed a chemically defined 13C-labeled substrate and NMR based experiments to simultaneously follow in real time the activity of HS biosynthetic enzymes and characterize the reaction products. Using this new approach, we report that the association of C5-epimerase and 2-O-sulfotransferase, which catalyze the production of iduronic acid and its 2-O-sulfation, respectively, is necessary to processively generate extended sequences of contiguous IdoA2S-containing disaccharides, whereas modifications are randomly introduced when the enzymes are uncoupled. These data shed light on the mechanisms by which HS motifs are generated during biosynthesis. They support the view that HS structure assembly is controlled not only by the availability of the biosynthetic enzymes but also by their physical association, which in the case of the C5-epimerase and 2-O-sulfotransferase was characterized by an affinity of 80 nM as demonstrated by surface plasmon resonance experiments.
Studies of proteoglycan involvement in CPP-mediated delivery.
Wittrup, Anders; Zhang, Si-He; Belting, Mattias
2011-01-01
Cell-penetrating peptides (CPPs) are widely used to deliver macromolecular cargoes to intracellular sites of action. Many CPPs have been demonstrated to rely on cell surface heparan sulfate proteoglycans (HSPGs) for efficient cellular entry and delivery. In this chapter, we describe methods for the study of PG involvement in CPP uptake. We provide descriptions of how to determine whether uptake of a CPP of interest is dependent on PGs. We also provide detailed protocols for the purification of PGs by anion-exchange chromatography as well as the characterization of the HSPG core protein composition of a cell line of interest. Finally, we present methods for modulating the expression level of specific HSPG core proteins as a means to determine the core protein specificity in the uptake of a particular CPP.
Important role of heparan sulfate in postnatal islet growth and insulin secretion
DOE Office of Scientific and Technical Information (OSTI.GOV)
Takahashi, Iwao; Noguchi, Naoya; Nata, Koji
2009-05-22
Heparan sulfate (HS) binds with several signaling molecules and regulates ligand-receptor interactions, playing an essential role in embryonic development. Here we showed that HS was intensively expressed in pancreatic islet {beta}-cells after 1 week of age in mice. The enzymatic removal of HS in isolated islets resulted in attenuated glucose-induced insulin secretion with a concomitant reduction in gene expression of several key components in the insulin secretion machinery. We further depleted islet HS by inactivating the exostosin tumor-like 3 gene specifically in {beta}-cells. These mice exhibited abnormal islet morphology with reduced {beta}-cell proliferation after 1 week of age and glucosemore » intolerance due to defective insulin secretion. These results demonstrate that islet HS is involved in the regulation of postnatal islet maturation and required to ensure normal insulin secretion.« less
Target cell cyclophilins facilitate human papillomavirus type 16 infection.
Bienkowska-Haba, Malgorzata; Patel, Hetalkumar D; Sapp, Martin
2009-07-01
Following attachment to primary receptor heparan sulfate proteoglycans (HSPG), human papillomavirus type 16 (HPV16) particles undergo conformational changes affecting the major and minor capsid proteins, L1 and L2, respectively. This results in exposure of the L2 N-terminus, transfer to uptake receptors, and infectious internalization. Here, we report that target cell cyclophilins, peptidyl-prolyl cis/trans isomerases, are required for efficient HPV16 infection. Cell surface cyclophilin B (CyPB) facilitates conformational changes in capsid proteins, resulting in exposure of the L2 N-terminus. Inhibition of CyPB blocked HPV16 infection by inducing noninfectious internalization. Mutation of a putative CyP binding site present in HPV16 L2 yielded exposed L2 N-terminus in the absence of active CyP and bypassed the need for cell surface CyPB. However, this mutant was still sensitive to CyP inhibition and required CyP for completion of infection, probably after internalization. Taken together, these data suggest that CyP is required during two distinct steps of HPV16 infection. Identification of cell surface CyPB will facilitate the study of the complex events preceding internalization and adds a putative drug target for prevention of HPV-induced diseases.
Epithelial-mesenchymal status influences how cells deposit fibrillin microfibrils.
Baldwin, Andrew K; Cain, Stuart A; Lennon, Rachel; Godwin, Alan; Merry, Catherine L R; Kielty, Cay M
2014-01-01
Here, we show that epithelial-mesenchymal status influences how cells deposit extracellular matrix. Retinal pigmented epithelial (RPE) cells that expressed high levels of E-cadherin and had cell-cell junctions rich in zona occludens (ZO)-1, β-catenin and heparan sulfate, required syndecan-4 but not fibronectin or protein kinase C α (PKCα) to assemble extracellular matrix (fibrillin microfibrils and perlecan). In contrast, RPE cells that strongly expressed mesenchymal smooth muscle α-actin but little ZO-1 or E-cadherin, required fibronectin (like fibroblasts) and PKCα, but not syndecan-4. Integrins α5β1 and/or α8β1 and actomyosin tension were common requirements for microfibril deposition, as was heparan sulfate biosynthesis. TGFβ, which stimulates epithelial-mesenchymal transition, altered gene expression and overcame the dependency on syndecan-4 for microfibril deposition in epithelial RPE cells, whereas blocking cadherin interactions disrupted microfibril deposition. Renal podocytes had a transitional phenotype with pericellular β-catenin but little ZO-1; they required syndecan-4 and fibronectin for efficient microfibril deposition. Thus, epithelial-mesenchymal status modulates microfibril deposition.
Interaction of herpes simplex virus glycoprotein gC with mammalian cell surface molecules.
Tal-Singer, R; Peng, C; Ponce De Leon, M; Abrams, W R; Banfield, B W; Tufaro, F; Cohen, G H; Eisenberg, R J
1995-01-01
The entry of herpes simplex virus (HSV) into mammalian cells is a multistep process beginning with an attachment step involving glycoproteins gC and gB. A second step requires the interaction of glycoprotein gD with a cell surface molecule. We explored the interaction between gC and the cell surface by using purified proteins in the absence of detergent. Truncated forms of gC and gD, gC1(457t), gC2(426t), and gD1(306t), lacking the transmembrane and carboxyl regions were expressed in the baculovirus system. We studied the ability of these proteins to bind to mammalian cells, to bind to immobilized heparin, to block HSV type 1 (HSV-1) attachment to cells, and to inhibit plaque formation by HSV-1. Each of these gC proteins bound to conformation-dependent monoclonal antibodies and to human complement component C3b, indicating that they maintained the same conformation of gC proteins expressed in mammalian cells. Biotinylated gC1(457t) and gC2(426t) each bind to several cell lines. Binding was inhibited by an excess of unlabeled gC but not by gD, indicating specificity. The attachment of gC to cells involves primarily heparan sulfate proteoglycans, since heparitinase treatment of cells reduced gC binding by 50% but had no effect on gD binding. Moreover, binding of gC to two heparan sulfate-deficient L-cell lines, gro2C and sog9, both of which are mostly resistant to HSV infection, was markedly reduced. Purified gD1 (306t), however, bound equally well to the two mutant cell lines. In contrast, saturating amounts of gC1(457t) interfered with HSV-1 attachment to cells but failed to block plaque formation, suggesting a role for gC in attachment but not penetration. A mutant form of gC lacking residues 33 to 123, gC1(delta 33-123t), expressed in the baculovirus system, bound significantly less well to cells than did gC1(457t) and competed poorly with biotinylated gC1(457t) for binding. These results suggest that residues 33 to 123 are important for gC attachment to cells. In contrast, both the mutant and wild-type forms of gC bound to immobilized heparin, indicating that binding of these proteins to the cell surface involves more than a simple interaction with heparin. To determine that the contribution of the N-terminal region of gC is important for HSV attachment, we compared several properties of a mutant HSV-1 which contains gC lacking amino acids 33 to 123 to those of its parental virus, which contains full-length gC. The mutant bound less well to cells than the parental virus but exhibited normal growth properties.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:7769707
Artemin Crystal Structure Reveals Insights into Heparan Sulfate Binding
DOE Office of Scientific and Technical Information (OSTI.GOV)
Silvian,L.; Jin, P.; Carmillo, P.
2006-01-01
Artemin (ART) promotes the growth of developing peripheral neurons by signaling through a multicomponent receptor complex comprised of a transmembrane tyrosine kinase receptor (cRET) and a specific glycosylphosphatidylinositol-linked co-receptor (GFR{alpha}3). Glial cell line-derived neurotrophic factor (GDNF) signals through a similar ternary complex but requires heparan sulfate proteoglycans (HSPGs) for full activity. HSPG has not been demonstrated as a requirement for ART signaling. We crystallized ART in the presence of sulfate and solved its structure by isomorphous replacement. The structure reveals ordered sulfate anions bound to arginine residues in the pre-helix and amino-terminal regions that were organized in a triad arrangementmore » characteristic of heparan sulfate. Three residues in the pre-helix were singly or triply substituted with glutamic acid, and the resulting proteins were shown to have reduced heparin-binding affinity that is partly reflected in their ability to activate cRET. This study suggests that ART binds HSPGs and identifies residues that may be involved in HSPG binding.« less
Factor h and properdin recognize different epitopes on renal tubular epithelial heparan sulfate.
Zaferani, Azadeh; Vivès, Romain R; van der Pol, Pieter; Navis, Gerjan J; Daha, Mohamed R; van Kooten, Cees; Lortat-Jacob, Hugues; Seelen, Marc A; van den Born, Jacob
2012-09-07
During proteinuria, renal tubular epithelial cells become exposed to ultrafiltrate-derived serum proteins, including complement factors. Recently, we showed that properdin binds to tubular heparan sulfates (HS). We now document that factor H also binds to tubular HS, although to a different epitope than properdin. Factor H was present on the urinary side of renal tubular cells in proteinuric, but not in normal renal tissues and colocalized with properdin in proteinuric kidneys. Factor H dose-dependently bound to proximal tubular epithelial cells (PTEC) in vitro. Preincubation of factor H with exogenous heparin and pretreatment of PTECs with heparitinase abolished the binding to PTECs. Surface plasmon resonance experiments showed high affinity of factor H for heparin and HS (K(D) values of 32 and 93 nm, respectively). Using a library of HS-like polysaccharides, we showed that chain length and high sulfation density are the most important determinants for glycosaminoglycan-factor H interaction and clearly differ from properdin-heparinoid interaction. Coincubation of properdin and factor H did not hamper HS/heparin binding of one another, indicating recognition of different nonoverlapping epitopes on HS/heparin by factor H and properdin. Finally we showed that certain low anticoagulant heparinoids can inhibit properdin binding to tubular HS, with a minor effect on factor H binding to tubular HS. As a result, these heparinoids can control the alternative complement pathway. In conclusion, factor H and properdin interact with different HS epitopes of PTECs. These interactions can be manipulated with some low anticoagulant heparinoids, which can be important for preventing complement-derived tubular injury in proteinuric renal diseases.
Anti-Tumor Activity of a Novel HS-Mimetic-Vascular Endothelial Growth Factor Binding Small Molecule
Sugahara, Kazuyuki; Thimmaiah, Kuntebommanahalli N.; Bid, Hemant K.; Houghton, Peter J.; Rangappa, Kanchugarakoppal S.
2012-01-01
The angiogenic process is controlled by variety of factors of which the vascular endothelial growth factor (VEGF) pathway plays a major role. A series of heparan sulfate mimetic small molecules targeting VEGF/VEGFR pathway has been synthesized. Among them, compound 8 (2-butyl-5-chloro-3-(4-nitro-benzyl)-3H-imidazole-4-carbaldehyde) was identified as a significant binding molecule for the heparin-binding domain of VEGF, determined by high-throughput-surface plasmon resonance assay. The data predicted strong binding of compound 8 with VEGF which may prevent the binding of VEGF to its receptor. We compared the structure of compound 8 with heparan sulfate (HS), which have in common the functional ionic groups such as sulfate, nitro and carbaldehyde that can be located in similar positions of the disaccharide structure of HS. Molecular docking studies predicted that compound 8 binds at the heparin binding domain of VEGF through strong hydrogen bonding with Lys-30 and Gln-20 amino acid residues, and consistent with the prediction, compound 8 inhibited binding of VEGF to immobilized heparin. In vitro studies showed that compound 8 inhibits the VEGF-induced proliferation migration and tube formation of mouse vascular endothelial cells, and finally the invasion of a murine osteosarcoma cell line (LM8G7) which secrets high levels of VEGF. In vivo, these effects produce significant decrease of tumor burden in an experimental model of liver metastasis. Collectively, these data indicate that compound 8 may prevent tumor growth through a direct effect on tumor cell proliferation and by inhibition of endothelial cell migration and angiogenesis mediated by VEGF. In conclusion, compound 8 may normalize the tumor vasculature and microenvironment in tumors probably by inhibiting the binding of VEGF to its receptor. PMID:22916091
Transmembrane proteoglycans control stretch-activated channels to set cytosolic calcium levels
Gopal, Sandeep; Søgaard, Pernille; Multhaupt, Hinke A.B.; Pataki, Csilla; Okina, Elena; Xian, Xiaojie; Pedersen, Mikael E.; Stevens, Troy; Griesbeck, Oliver; Park, Pyong Woo; Pocock, Roger
2015-01-01
Transmembrane heparan sulfate proteoglycans regulate multiple aspects of cell behavior, but the molecular basis of their signaling is unresolved. The major family of transmembrane proteoglycans is the syndecans, present in virtually all nucleated cells, but with mostly unknown functions. Here, we show that syndecans regulate transient receptor potential canonical (TRPCs) channels to control cytosolic calcium equilibria and consequent cell behavior. In fibroblasts, ligand interactions with heparan sulfate of syndecan-4 recruit cytoplasmic protein kinase C to target serine714 of TRPC7 with subsequent control of the cytoskeleton and the myofibroblast phenotype. In epidermal keratinocytes a syndecan–TRPC4 complex controls adhesion, adherens junction composition, and early differentiation in vivo and in vitro. In Caenorhabditis elegans, the TRPC orthologues TRP-1 and -2 genetically complement the loss of syndecan by suppressing neuronal guidance and locomotory defects related to increases in neuronal calcium levels. The widespread and conserved syndecan–TRPC axis therefore fine tunes cytoskeletal organization and cell behavior. PMID:26391658
Martins, Carla; Hůlková, Helena; Dridi, Larbi; Dormoy-Raclet, Virginie; Grigoryeva, Lubov; Choi, Yoo; Langford-Smith, Alexander; Wilkinson, Fiona L.; Ohmi, Kazuhiro; DiCristo, Graziella; Hamel, Edith; Ausseil, Jerôme; Cheillan, David; Moreau, Alain; Svobodová, Eva; Hájková, Zuzana; Tesařová, Markéta; Hansíková, Hana; Bigger, Brian W.; Hrebícek, Martin
2015-01-01
Severe progressive neurological paediatric disease mucopolysaccharidosis III type C is caused by mutations in the HGSNAT gene leading to deficiency of acetyl-CoA: α-glucosaminide N-acetyltransferase involved in the lysosomal catabolism of heparan sulphate. To understand the pathophysiology of the disease we generated a mouse model of mucopolysaccharidosis III type C by germline inactivation of the Hgsnat gene. At 6–8 months mice showed hyperactivity, and reduced anxiety. Cognitive memory decline was detected at 10 months and at 12–13 months mice showed signs of unbalanced hesitant walk and urinary retention. Lysosomal accumulation of heparan sulphate was observed in hepatocytes, splenic sinus endothelium, cerebral microglia, liver Kupffer cells, fibroblasts and pericytes. Starting from 5 months, brain neurons showed enlarged, structurally abnormal mitochondria, impaired mitochondrial energy metabolism, and storage of densely packed autofluorescent material, gangliosides, lysozyme, phosphorylated tau, and amyloid-β. Taken together, our data demonstrate for the first time that deficiency of acetyl-CoA: α-glucosaminide N-acetyltransferase causes lysosomal accumulation of heparan sulphate in microglial cells followed by their activation and cytokine release. They also show mitochondrial dysfunction in the neurons and neuronal loss explaining why mucopolysaccharidosis III type C manifests primarily as a neurodegenerative disease. PMID:25567323
Genetics Home Reference: mucopolysaccharidosis type III
... breakdown of a subset of GAGs called heparan sulfate. MPS IIIA is caused by mutations in the ... of these enzymes disrupts the breakdown of heparan sulfate. As a result, partially broken down heparan sulfate ...
Vivès, R R; Goodger, S; Pye, D A
2001-02-15
Heparan sulphates are highly sulphated linear polysaccharides involved in many cellular functions. Their biological properties stem from their ability to interact with a wide range of proteins. An increasing number of studies, using heparan sulphate-derived oligosaccharides, suggest that specific structural features within the polysaccharide are responsible for ligand recognition and regulation. In the present study, we show that strong anion-exchange HPLC alone, a commonly used technique for purification of heparan sulphate-derived oligosaccharides, may not permit the isolation of highly pure heparan sulphate oligosaccharide species. This was determined by PAGE analysis of hexa-, octa- and decasaccharide samples deemed to be pure by strong anion-exchange HPLC. In addition, subtle differences in the positioning of sulphate groups within heparan sulphate hexasaccharides were impossible to detect by strong anion-exchange HPLC. PAGE analysis on the other hand afforded excellent resolution of these structural isomers. The precise positioning of specific sulphate groups has been implicated in determining the specificity of heparan sulphate interactions and biological activities; hence, the purification of oligosaccharide species that differ in this way becomes an important issue. In this study, we have used strong anion-exchange HPLC and PAGE techniques to allow production of the homogeneous heparan sulphate oligosaccharide species that will be required for the detailed study of structure/activity relationships.
Iwamoto, Ryo; Mine, Naoki; Kawaguchi, Taichiro; Minami, Seigo; Saeki, Kazuko; Mekada, Eisuke
2010-07-01
HB-EGF, a member of the EGF family of growth factors, plays an important role in cardiac valve development by suppressing mesenchymal cell proliferation. Here, we show that HB-EGF must interact with heparan sulfate proteoglycans (HSPGs) to properly function in this process. In developing valves, HB-EGF is synthesized in endocardial cells but accumulates in the mesenchyme by interacting with HSPGs. Disrupting the interaction between HB-EGF and HSPGs in an ex vivo model of endocardial cushion explants resulted in increased mesenchymal cell proliferation. Moreover, homozygous knock-in mice (HB(Delta)(hb/)(Delta)(hb)) expressing a mutant HB-EGF that cannot bind to HSPGs developed enlarged cardiac valves with hyperproliferation of mesenchymal cells; this resulted in a phenotype that resembled that of Hbegf-null mice. Interestingly, although Hbegf-null mice had abnormal heart chambers and lung alveoli, HB(Delta)(hb/)(Delta)(hb) mice did not exhibit these defects. These results indicate that interactions with HSPGs are essential for the function of HB-EGF, especially in cardiac valve development, in which HB-EGF suppresses mesenchymal cell proliferation.
Paquet, Sophie; Daude, Nathalie; Courageot, Marie-Pierre; Chapuis, Jérôme; Laude, Hubert; Vilette, Didier
2007-01-01
We have studied the interactions of exogenous prions with an epithelial cell line inducibly expressing PrPc protein and permissive to infection by a sheep scrapie agent. We demonstrate that abnormal PrP (PrPSc) and prion infectivity are efficiently internalized in Rov cells, whether or not PrPc is expressed. At odds with earlier studies implicating cellular heparan sulfates in PrPSc internalization, we failed to find any involvement of such molecules in Rov cells, indicating that prions can enter target cells by several routes. We further show that PrPSc taken up in the absence of PrPc was unable to promote efficient prion multiplication once PrPc expression was restored in the cells. This observation argues that interaction of PrPSc with PrPc has to occur early, in a specific subcellular compartment(s), and is consistent with the view that the first prion multiplication events may occur at the cell surface. PMID:17626095
Simeonovic, Charmaine J; Popp, Sarah K; Starrs, Lora M; Brown, Debra J; Ziolkowski, Andrew F; Ludwig, Barbara; Bornstein, Stefan R; Wilson, J Dennis; Pugliese, Alberto; Kay, Thomas W H; Thomas, Helen E; Loudovaris, Thomas; Choong, Fui Jiun; Freeman, Craig; Parish, Christopher R
2018-01-01
Type 1 diabetes (T1D) is an autoimmune disease in which insulin-producing beta cells in pancreatic islets are progressively destroyed. Clinical trials of immunotherapies in recently diagnosed T1D patients have only transiently and partially impacted the disease course, suggesting that other approaches are required. Our previous studies have demonstrated that heparan sulfate (HS), a glycosaminoglycan conventionally expressed in extracellular matrix, is present at high levels inside normal mouse beta cells. Intracellular HS was shown to be critical for beta cell survival and protection from oxidative damage. T1D development in Non-Obese Diabetic (NOD) mice correlated with loss of islet HS and was prevented by inhibiting HS degradation by the endoglycosidase, heparanase. In this study we investigated the distribution of HS and heparan sulfate proteoglycan (HSPG) core proteins in normal human islets, a role for HS in human beta cell viability and the clinical relevance of intra-islet HS and HSPG levels, compared to insulin, in human T1D. In normal human islets, HS (identified by 10E4 mAb) co-localized with insulin but not glucagon and correlated with the HSPG core proteins for collagen type XVIII (Col18) and syndecan-1 (Sdc1). Insulin-positive islets of T1D pancreases showed significant loss of HS, Col18 and Sdc1 and heparanase was strongly expressed by islet-infiltrating leukocytes. Human beta cells cultured with HS mimetics showed significantly improved survival and protection against hydrogen peroxide-induced death, suggesting that loss of HS could contribute to beta cell death in T1D. We conclude that HS depletion in beta cells, possibly due to heparanase produced by insulitis leukocytes, may function as an important mechanism in the pathogenesis of human T1D. Our findings raise the possibility that intervention therapy with dual activity HS replacers/heparanase inhibitors could help to protect the residual beta cell mass in patients recently diagnosed with T1D.
2012-01-01
Background Overcoming platinum resistance is a major obstacle in the treatment of Epithelial Ovarian Cancer (EOC). In our previous work Decoy Receptor 3 (DcR3) was found to be related to platinum resistance. The major objective of this work was to define the cellular interaction of DcR3 with EOC and to explore its effects on platinum responsiveness. Methods We studied cell lines and primary cultures for the expression of and the cells ability to bind DcR3. Cells were cultured with DcR3 and then exposed to platinum. Cell viability was determined by MTT assay. Finally, the cells molecular response to DcR3 was studied using real time RT-PCR based differential expression arrays, standard RT-PCR, and Western blot. Results High DcR3 in the peritoneal cavity of women with EOC is associated with significantly shorter time to first recurrence after platinum based therapy (p = 0.02). None-malignant cells contribute DcR3 in the peritoneal cavity. The cell lines studied do not secrete DcR3; however they all bind exogenous DcR3 to their surface implying that they can be effected by DcR3 from other sources. DcR3s protein binding partners are minimally expressed or negative, however, all cells expressed the DcR3 binding Heparan Sulfate Proteoglycans (HSPGs) Syndecans-2, and CD44v3. DcR3 binding was inhibited by heparin and heparinase. After DcR3 exposure both SKOV-3 and OVCAR-3 became more resistant to platinum with 15% more cells surviving at high doses. On the contrary CaOV3 became more sensitive to platinum with 20–25% more cell death. PCR array analysis showed increase expression of BRCA1 mRNA in SKOV-3 and OVCAR-3 and decreased BRCA1 expression in CaOV-3 after exposure to DcR3. This was confirmed by gene specific real time PCR and Western blot analysis. Conclusions Non-malignant cells contribute to the high levels of DcR3 in ovarian cancer. DcR3 binds readily to EOC cells via HSPGs and alter their responsiveness to platinum chemotherapy. The paradoxical responses seen were related to the expression pattern of HSPGs available on the cells surface to interact with. Although the mechanism behind this is not completely known alterations in DNA repair pathways including the expression of BRCA1 appear to be involved. PMID:22583667
Cell-Surface Bound Nonreceptors and Signaling Morphogen Gradients
Wan, Frederic Y.M.
2013-01-01
The patterning of many developing tissues is orchestrated by gradients of signaling morphogens. Included among the molecular events that drive the formation of morphogen gradients are a variety of elaborate regulatory interactions. Such interactions are thought to make gradients robust, i.e. insensitive to change in the face of genetic or environmental perturbations. But just how this is accomplished is a major unanswered question. Recently extensive numerical simulations suggest that robustness of signaling gradients can be achieved through morphogen degradation mediated by cell surface bound non-signaling receptor molecules (or nonreceptors for short) such as heparan sulfate proteoglycans (HSPG). The present paper provides a mathematical validation of the results from the aforementioned numerical experiments. Extension of a basic extracellular model to include reversible binding with nonreceptors synthesized at a prescribed rate and mediated morphogen degradation shows that the signaling gradient diminishes with increasing concentration of cell-surface nonreceptors. Perturbation and asymptotic solutions obtained for i) low (receptor and nonreceptor) occupancy, and ii) high nonreceptor concntration permit more explicit delineation of the effects of nonreceptors on signaling gradients and facilitate the identification of scenarios in which the presence of nonreceptors may or may not be effective in promoting robustness. PMID:25232201
Makoveichuk, Elena; Castel, Susanna; Vilaró, Senen; Olivecrona, Gunilla
2004-11-08
Lipoprotein lipase (LPL) is produced by cells in the artery wall and can mediate binding of lipoproteins to cell surface heparan sulfate proteoglycans (HSPG), resulting in endocytosis (the bridging function). Active, dimeric LPL may dissociate to inactive monomers, the main form found in plasma. We have studied binding/internalization of human low density lipoprotein (LDL), mediated by bovine LPL, using THP-1 monocytes and macrophages. Uptake of (125)I-LDL was similar in monocytes and macrophages and was not affected by the LDL-receptor family antagonist receptor-associated protein (RAP) or by the phagocytosis inhibitor cytochalasin D. In contrast, uptake depended on HSPG and on membrane cholesterol. Incubation in the presence of dexamethasone increased the endogenous production of LPL by the cells and also increased LPL-mediated binding of LDL to the cell surfaces. Monomeric LPL was bound to the cells mostly in a heparin-resistant fashion. We conclude that the uptake of LDL mediated by LPL dimers is receptor-independent and involves cholesterol-enriched membrane areas (lipid rafts). Dimeric and monomeric LPL differ in their ability to mediate binding/uptake of LDL, probably due to different mechanisms for binding/internalization.
NASA Astrophysics Data System (ADS)
Izumikawa, Tomomi; Sato, Ban; Kitagawa, Hiroshi
2014-01-01
Chondroitin sulfate (CS) proteoglycans are present on the surfaces of virtually all cells and in the extracellular matrix and are required for cytokinesis at early developmental stages. Studies have shown that heparan sulfate (HS) is essential for maintaining mouse embryonic stem cells (ESCs) that are primed for differentiation, whereas the function of CS has not yet been elucidated. To clarify the role of CS, we generated glucuronyltransferase-I-knockout ESCs lacking CS. We found that CS was required to maintain the pluripotency of ESCs and promoted initial ESC commitment to differentiation compared with HS. In addition, CS-A and CS-E polysaccharides, but not CS-C polysaccharides, bound to E-cadherin and enhanced ESC differentiation. Multiple-lineage differentiation was inhibited in chondroitinase ABC-digested wild-type ESCs. Collectively, these results suggest that CS is a novel determinant in controlling the functional integrity of ESCs via binding to E-cadherin.
Doncel-Pérez, Ernesto; Aranaz, Inmaculada; Bastida, Agatha; Revuelta, Julia; Camacho, Celia; Acosta, Niuris; Garrido, Leoncio; Civera, Concepción; García-Junceda, Eduardo; Heras, Angeles; Fernández-Mayoralas, Alfonso
2018-07-01
Despite the relevant biological functions of heparan sulfate (HS) glycosaminoglycans, their limited availability and the chemical heterogeneity from natural sources hamper their use for biomedical applications. Chitosan sulfates (ChS) exhibit structural similarity to HSs and may mimic their biological functions. We prepared a variety of ChS with different degree of sulfation to evaluate their ability to mimic HS in protein binding and to promote neural cell division and differentiation. The structure of the products was characterized using various spectroscopic and analytical methods. The study of their interaction with different growth factors showed that ChS bound to the proteins similarly or even better than heparin. In cell cultures, a transition effect on cell number was observed as a function of ChS concentration. Differences in promoting the expression of the differentiation markers were also found depending on the degree of sulfation and modification in the chitosan. Copyright © 2018 Elsevier Ltd. All rights reserved.
Vanpouille, Christophe; Deligny, Audrey; Delehedde, Maryse; Denys, Agnès; Melchior, Aurélie; Liénard, Xavier; Lyon, Malcolm; Mazurier, Joël; Fernig, David G; Allain, Fabrice
2007-08-17
Many of the biological functions of heparan sulfate (HS) proteoglycans can be attributed to specialized structures within HS moieties, which are thought to modulate binding and function of various effector proteins. Cyclophilin B (CyPB), which was initially identified as a cyclosporin A-binding protein, triggers migration and integrin-mediated adhesion of peripheral blood T lymphocytes by a mechanism dependent on interaction with cell surface HS. Here we determined the structural features of HS that are responsible for the specific binding of CyPB. In addition to the involvement of 2-O,6-O, and N-sulfate groups, we also demonstrated that binding of CyPB was dependent on the presence of N-unsubstituted glucosamine residues (GlcNH2), which have been reported to be precursors for sulfation by 3-O-sulfotransferases-3 (3-OST-3). Interestingly, 3-OST-3B isoform was found to be the main 3-OST isoenzyme expressed in peripheral blood T lymphocytes and Jurkat T cells. Moreover, down-regulation of the expression of 3-OST-3 by RNA interference potently reduced CyPB binding and consequent activation of p44/42 mitogen-activated protein kinases. Altogether, our results strongly support the hypothesis that 3-O-sulfation of GlcNH2 residues could be a key modification that provides specialized HS structures for CyPB binding to responsive cells. Given that 3-O-sulfation of GlcNH2-containing HS by 3-OST-3 also provides binding sites for glycoprotein gD of herpes simplex virus type I, these findings suggest an intriguing structural linkage between the HS sequences involved in CyPB binding and viral infection.
A Small Molecule Inhibits Virion Attachment to Heparan Sulfate- or Sialic Acid-Containing Glycans
Colpitts, Che C.
2014-01-01
ABSTRACT Primary attachment to cellular glycans is a critical entry step for most human viruses. Some viruses, such as herpes simplex virus type 1 (HSV-1) and hepatitis C virus (HCV), bind to heparan sulfate, whereas others, such as influenza A virus (IAV), bind to sialic acid. Receptor mimetics that interfere with these interactions are active against viruses that bind to either heparan sulfate or to sialic acid. However, no molecule that inhibits the attachment of viruses in both groups has yet been identified. Epigallocatechin gallate (EGCG), a green tea catechin, is active against many unrelated viruses, including several that bind to heparan sulfate or to sialic acid. We sought to identify the basis for the broad-spectrum activity of EGCG. Here, we show that EGCG inhibits the infectivity of a diverse group of enveloped and nonenveloped human viruses. EGCG acts directly on the virions, without affecting the fluidity or integrity of the virion envelopes. Instead, EGCG interacts with virion surface proteins to inhibit the attachment of HSV-1, HCV, IAV, vaccinia virus, adenovirus, reovirus, and vesicular stomatitis virus (VSV) virions. We further show that EGCG competes with heparan sulfate for binding of HSV-1 and HCV virions and with sialic acid for binding of IAV virions. Therefore, EGCG inhibits unrelated viruses by a common mechanism. Most importantly, we have identified EGCG as the first broad-spectrum attachment inhibitor. Our results open the possibility for the development of small molecule broad-spectrum antivirals targeting virion attachment. IMPORTANCE This study shows that it is possible to develop a small molecule antiviral or microbicide active against the two largest groups of human viruses: those that bind to glycosaminoglycans and those that bind to sialoglycans. This group includes the vast majority of human viruses, including herpes simplex viruses, cytomegalovirus, influenza virus, poxvirus, hepatitis C virus, HIV, and many others. PMID:24789779
Cancer Cell Glycocalyx Mediates Mechanostransduction and Flow-Regulated Invasion
Qazi, Henry; Palomino, Rocio; Shi, Zhong-Dong; Munn, Lance L.; Tarbell, John M.
2014-01-01
Mammalian cells are covered by a surface proteoglycan (glycocalyx) layer, and it is known that blood vessel-lining endothelial cells use the glycocalyx to sense and transduce the shearing forces of blood flow into intracellular signals. Tumor cells in vivo are exposed to forces from interstitial fluid flow that may affect metastatic potential but are not reproduced by most in vitro cell motility assays. We hypothesized that glycocalyx-mediated mechanotransduction of interstitial flow shear stress is an un-recognized factor that can significantly enhance metastatic cell motility and play a role in augmentation of invasion. Involvement of MMP levels, cell adhesion molecules (CD44, α3 integrin), and glycocalyx components (heparan sulfate and hyaluronan) were investigated in a cell/collagen gel suspension model designed to mimic the interstitial flow microenvironment. Physiologic levels of flow upregulated MMP levels and enhanced the motility of metastatic cells. Blocking the flow-enhanced expression of MMP actvity or adhesion molecules (CD44 and integrins) resulted in blocking the flow-enhanced migratory activity. The presence of a glycocalyx-like layer was verified around tumor cells, and the degradation of this layer by hyaluronidase and heparinase blocked the flow-regulated invasion. This study shows for the first time that interstitial flow enhancement of metastatic cell motility can be mediated by the cell surface glycocalyx – a potential target for therapeutics. PMID:24077103
Changes in cat urinary glycosaminoglycans with age and in feline urologic syndrome.
Pereira, Daionety A; Aguiar, Jair A K; Hagiwara, Mitika K; Michelacci, Yara M
2004-04-07
The aim of the present study was to characterize the urinary excretion of glycosaminoglycans in kittens and adult healthy cats, as well as in cats with a low urinary tract disease, the feline urologic syndrome (FUS). The main urinary glycosaminoglycan in cats was found to be chondroitin sulfate, with smaller amounts of dermatan sulfate and heparan sulfate. There was no difference in the urinary glycosaminoglycan concentration with sex, but a marked decrease occurred with age, due to chondroitin sulfate. Trace amounts of keratan sulfate were also detected in the urine of kittens, but not of healthy adult cats. Dermatan sulfate and heparan sulfate were the only glycosaminoglycans found in the urinary tract and kidney, and chondroitin sulfate was the only glycosaminoglycan found in the plasma. These data suggest that the main urinary glycosaminoglycan chondroitin sulfate is of systemic origin and filtered in the kidney, while the minor components dermatan sulfate and heparan sulfate may come from the urinary tract. The urinary glycosaminoglycan concentration was greatly decreased in animals with FUS, as compared to normal adults. We hypothesize that these low glycosaminoglycan levels reflect a damage to the bladder surface, resulting in absorption and/or degradation of the endogenous urinary glycosaminoglycans.
Perturbation of the endothelial glycocalyx in post cardiac arrest syndrome.
Grundmann, Sebastian; Fink, Katrin; Rabadzhieva, Lyubomira; Bourgeois, Natascha; Schwab, Tilmann; Moser, Martin; Bode, Christoph; Busch, Hans-Joerg
2012-06-01
The prognosis of immediate survivors of cardiac arrest remains poor, as the majority of these patients develops an inflammatory disorder known as the post-cardiac arrest syndrome (PCAS). Recently, the endothelial glycocalyx has been shown to be a key modulator of vascular permeability and inflammation, but its role in PCAS remains unknown. Plasma levels of the glycocalyx components syndecan-1, heparan sulfate and hyaluronic acid were measured in 25 patients after immediate survival of cardiac arrest during different phases of PCAS. Twelve hemodynamically stable patients with acute coronary syndrome served as controls. Cardiac arrest resulted in a significant increase in syndecan-1, heparan sulfate and hyaluronic acid levels compared to controls, indicating a shedding of the endothelial glycocalyx as a pathophysiological component of the post cardiac arrest syndrome. The time course differed between the individual glycocalyx components, with a higher increase of syndecan-1 in the early phase of PCAS (2.8-fold increase vs. controls) and a later peak of heparan sulfate (1.7-fold increase) and hyaluronic acid (2-fold increase) in the intermediate phase. Only the plasma levels of syndecan-1 correlated positively with the duration of CPR and negatively with the glycocalyx-protective protease inhibitor antithrombin III. Plasma levels of both syndecan-1 and heparan sulfate were higher in eventual non-survivors than in survivors of cardiac arrest. Our data for the first time demonstrates a perturbation of the endothelial glycocalyx in immediate survivors of cardiac arrest and indicate a potential important role of this endothelial surface layer in the development of post-cardiac arrest syndrome. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.
Yasen, Aizezi; Herrera, Rossana; Rosbe, Kristina; Lien, Kathy; Tugizov, Sharof M.
2018-01-01
Recently, we showed that HIV-1 is sequestered, i.e., trapped, in the intracellular vesicles of oral and genital epithelial cells. Here, we investigated the mechanisms of HIV-1 sequestration in vesicles of polarized tonsil, foreskin and cervical epithelial cells. HIV-1 internalization into epithelial cells is initiated by multiple entry pathways, including clathrin-, caveolin/lipid raft-associated endocytosis and macropinocytosis. Inhibition of HIV-1 attachment to galactosylceramide and heparan sulfate proteoglycans, and virus endocytosis and macropinocytosis reduced HIV-1 sequestration by 30–40%. T-cell immunoglobulin and mucin domain 1 (TIM-1) were expressed on the apical surface of polarized tonsil, cervical and foreskin epithelial cells. However, TIM-1-associated HIV-1 macropinocytosis and sequestration were detected mostly in tonsil epithelial cells. Sequestered HIV-1 was resistant to trypsin, pronase, and soluble CD4, indicating that the sequestered virus was intracellular. Inhibition of HIV-1 intraepithelial sequestration and elimination of vesicles containing virus in the mucosal epithelium may help in the prevention of HIV-1 mucosal transmission. PMID:29277006
MacArthur, Jennifer M.; Bishop, Joseph R.; Stanford, Kristin I.; Wang, Lianchun; Bensadoun, André; Witztum, Joseph L.; Esko, Jeffrey D.
2007-01-01
We examined the role of hepatic heparan sulfate in triglyceride-rich lipoprotein metabolism by inactivating the biosynthetic gene GlcNAc N-deacetylase/N-sulfotransferase 1 (Ndst1) in hepatocytes using the Cre-loxP system, which resulted in an approximately 50% reduction in sulfation of liver heparan sulfate. Mice were viable and healthy, but they accumulated triglyceride-rich lipoprotein particles containing apoB-100, apoB-48, apoE, and apoCI-IV. Compounding the mutation with LDL receptor deficiency caused enhanced accumulation of both cholesterol- and triglyceride-rich particles compared with mice lacking only LDL receptors, suggesting that heparan sulfate participates in the clearance of cholesterol-rich lipoproteins as well. Mutant mice synthesized VLDL normally but showed reduced plasma clearance of human VLDL and a corresponding reduction in hepatic VLDL uptake. Retinyl ester excursion studies revealed that clearance of intestinally derived lipoproteins also depended on hepatocyte heparan sulfate. These findings show that under normal physiological conditions, hepatic heparan sulfate proteoglycans play a crucial role in the clearance of both intestinally derived and hepatic lipoprotein particles. PMID:17200715
Simon-Assmann, P; Bouziges, F; Daviaud, D; Haffen, K; Kedinger, M
1987-08-15
Among the extracellular matrix components which have been suggested to be involved in developmental and neoplastic changes are glycosaminoglycans (GAGs). To try to correlate their amount and nature with the process of enterocytic differentiation, we studied glycosaminoglycan synthesis of human colonic adenocarcinoma cells (HT29 cell line) by [3H]glucosamine and [35S]sulfate incorporation. Enterocytic differentiation of the cells obtained in a sugar-free medium (for review, see A. Zweibaum et al. In: Handbook of Physiology. Intestinal Transport of the Gastrointestinal System, in press, 1987) resulted in a marked increase in total incorporation of labeled precursors (20-fold for [3H]glucosamine, 4.5-fold for [35S]sulfate) as well as in uronic acid content (5-fold); most of the synthesized GAGs were found associated with the cell pellet. Chromatographic and electrophoretic analysis of the labeled GAGs revealed that undifferentiated cells synthesized and secreted hyaluronic acid, heparan sulfate, and one class of chondroitin sulfate. Differentiation of HT29 cells because associated with the synthesis of an additional class of chondroitin sulfate (CS4) concomitant to a decrease in heparan sulfate which is no longer found secreted in the medium. Furthermore, the charge density of this latter GAG component varied as assessed by a shift of its affinity on ion-exchange chromatography.
Early events in herpes simplex virus lifecycle with implications for an infection of lifetime.
Salameh, Sarah; Sheth, Urmi; Shukla, Deepak
2012-01-01
Affecting a large percentage of human population herpes simplex virus (HSV) types -1 and -2 mainly cause oral, ocular, and genital diseases. Infection begins with viral entry into a host cell, which may be preceded by viral "surfing" along filopodia. Viral glycoproteins then bind to one or more of several cell surface receptors, such as herpesvirus entry mediator (HVEM), nectin-1, 3-O sulfated heparan sulfate (3-OS HS), paired immunoglobulin-like receptor α, and non-muscle myosin-IIA. At least five viral envelope glycoproteins participate in entry and these include gB, gC, gD and gH-gL. Post-entry, these glycoproteins may also facilitate cell-to-cell spread of the virus, which helps in the evasion of physical barriers as well as several components of the innate and adaptive immune responses. The spread may be facilitated by membrane fusion, movement across tight junctions, transfer across neuronal synapses, or the recruitment of actin-containing structures. This review summarizes some of the recent advances in our understanding of HSV entry and cell-to-cell spread.
Becker, Maria; Benromano, Tali; Shahar, Abraham; Nevo, Zvi; Pick, Chaim G
2014-12-01
Peripheral neuropathy is one of the main complications of diabetes mellitus. The current study demonstrated the bimodal pattern of diabetic peripheral neuropathy found in the behavioral study of pain perception in parallel to the histopathological findings in dorsal root ganglia (DRGs) neurons and satellite Schwann cell basement membranes. A gradual decrease in heparan sulfate content, with a reciprocal increase in deposited laminin in the basement membranes of dorsal root ganglia Schwann cells, was shown in streptozotocin-treated rats. In addition, the characteristic biphasic pain profiles were demonstrated in diabetic rats, as shown by hypersensitivity at the third week and hyposensitivity at the tenth week post-streptozotocin injection, accompanied by a continuous decrease in the sciatic nerve conduction velocity. It appears that these basal membrane abnormalities in content of heparan sulfate and laminin, noticed in diabetic rats, may underline the primary damage in dorsal ganglion sensory neurons, simultaneously with the bimodal painful profile in diabetic peripheral neuropathy, simulating the scenario of filtration rate in diabetic kidney.
Takegawa, Yasuhiro; Araki, Kayo; Fujitani, Naoki; Furukawa, Jun-ichi; Sugiyama, Hiroaki; Sakai, Hideaki; Shinohara, Yasuro
2011-12-15
Glycosaminoglycans (GAGs) play important roles in cell adhesion and growth, maintenance of extracellular matrix (ECM) integrity, and signal transduction. To fully understand the biological functions of GAGs, there is a growing need for sensitive, rapid, and quantitative analysis of GAGs. The present work describes a novel analytical technique that enables high throughput cellular/tissue glycosaminoglycomics for all three families of uronic acid-containing GAGs, hyaluronan (HA), chondroitin sulfate (CS)/dermatan sulfate (DS), and heparan sulfate (HS). A one-pot purification and labeling procedure for GAG Δ-disaccharides was established by chemo-selective ligation of disaccharides onto high density hydrazide beads (glycoblotting) and subsequent labeling by fluorescence. The 17 most common disaccharides (eight comprising HS, eight CS/DS, and one comprising HA) could be separated with a single chromatography for the first time by employing a zwitter-ionic type of hydrophilic-interaction chromatography column. These novel analytical techniques were able to precisely characterize the glycosaminoglycome in various cell types including embryonal carcinoma cells and ocular epithelial tissues (cornea, conjunctiva, and limbus).
Heparan Sulfate Differences in Rheumatoid Arthritis versus Healthy Sera
López-Hoyos, Marcos; Seo, Youjin; Andaya, Armann; Leary, Julie A.
2015-01-01
Heparan sulfate (HS) is a complex and highly variable polysaccharide, expressed ubiquitously on the cell surface as HS proteoglycans (HSPGs), and found in the extracellular matrix as free HS fragments. Its heterogeneity due to various acetylation and sulfation patterns endows a multitude of functions. In animal tissues, HS interacts with a wide range of proteins to mediate numerous biological activities; given its multiple roles in inflammation processes, characterization of HS in human serum has significant potential for elucidating disease mechanisms. Historically, investigation of HS was limited by its low concentration in human serum, together with the complexity of the serum matrix. In this study, we used a modified mass spectrometry method to examine HS disaccharide profiles in the serum of 50 women with rheumatoid arthritis (RA), and compared our results to 51 sera from healthy women. Using various purification methods and online LC-MS/MS, we discovered statistically significant differences in the sulfation and acetylation patterns between populations. Since early diagnosis of RA is considered important in decelerating the disease's progression, identification of specific biomolecule characterizations may provide crucial information towards developing new therapies for suppressing the disease in its early stages. This is the first report of potential glycosaminoglycan biomarkers for RA found in human sera, while acknowledging the obvious fact that a larger population set, and more stringent collection parameters, will need to be investigated in the future. PMID:25217862
Riblett, Amber M; Blomen, Vincent A; Jae, Lucas T; Altamura, Louis A; Doms, Robert W; Brummelkamp, Thijn R; Wojcechowskyj, Jason A
2016-02-01
Rift Valley fever virus (RVFV) causes recurrent insect-borne epizootics throughout the African continent, and infection of humans can lead to a lethal hemorrhagic fever syndrome. Deep mutagenesis of haploid human cells was used to identify host factors required for RVFV infection. This screen identified a suite of enzymes involved in glycosaminoglycan (GAG) biogenesis and transport, including several components of the cis-oligomeric Golgi (COG) complex, one of the central components of Golgi complex trafficking. In addition, disruption of PTAR1 led to RVFV resistance as well as reduced heparan sulfate surface levels, consistent with recent observations that PTAR1-deficient cells exhibit altered Golgi complex morphology and glycosylation defects. A variety of biochemical and genetic approaches were utilized to show that both pathogenic and attenuated RVFV strains require GAGs for efficient infection on some, but not all, cell types, with the block to infection being at the level of virion attachment. Examination of other members of the Bunyaviridae family for GAG-dependent infection suggested that the interaction with GAGs is not universal among bunyaviruses, indicating that these viruses, as well as RVFV on certain cell types, employ additional unidentified virion attachment factors and/or receptors. Rift Valley fever virus (RVFV) is an emerging pathogen that can cause severe disease in humans and animals. Epizootics among livestock populations lead to high mortality rates and can be economically devastating. Human epidemics of Rift Valley fever, often initiated by contact with infected animals, are characterized by a febrile disease that sometimes leads to encephalitis or hemorrhagic fever. The global burden of the pathogen is increasing because it has recently disseminated beyond Africa, which is of particular concern because the virus can be transmitted by widely distributed mosquito species. There are no FDA-licensed vaccines or antiviral agents with activity against RVFV, and details of its life cycle and interaction with host cells are not well characterized. We used the power of genetic screening in human cells and found that RVFV utilizes glycosaminoglycans to attach to host cells. This furthers our understanding of the virus and informs the development of antiviral therapeutics. Copyright © 2016, American Society for Microbiology. All Rights Reserved.
Baxter, M A; Wynn, R F; Schyma, L; Holmes, D K; Wraith, J E; Fairbairn, L J; Bellantuono, I
2005-01-01
Bone marrow transplantation is the therapy of choice in patients affected by MPS I (Hurler syndrome), but a high incidence of rejection limits the success of this treatment. The deficiency of alpha-L-iduronidase (EC 1.2.3.76), one of the enzymes responsible for the degradation of glycosaminoglycans, results in accumulation of heparan and dermatan sulphate in these patients. Heparan sulphate and dermatan sulphate are known to be important components of the bone marrow microenvironment and critical for haematopoietic cell development. In this study we compared the ability of marrow stromal cells from MPS I patients and healthy donors to support normal haematopoiesis in Dexter-type long term culture. We found an inverse stroma/supernatant ratio in the number of clonogenic progenitors, particularly the colony-forming unit granulocyte-machrophage in MPS I cultures when compared to normal controls. No alteration in the adhesion of haematopoietic cells to the stroma of MPS I patients was found, suggesting that the altered distribution in the number of clonogenic progenitors is probably the result of an accelerated process of differentiation and maturation. The use of alpha-L-iduronidase gene-corrected marrow stromal cells re-established normal haematopoiesis in culture, suggesting that correction of the bone marrow microenvironment with competent enzyme prior to transplantation might help establishment of donor haematopoiesis.
Byrne, Dominic P; Li, Yong; Ramakrishnan, Krithika; Barsukov, Igor L; Yates, Edwin A; Eyers, Claire E; Papy-Garcia, Dulcé; Chantepie, Sandrine; Pagadala, Vijayakanth; Lu, Jian; Wells, Carrow; Drewry, David H; Zuercher, William J; Berry, Neil G; Fernig, David G; Eyers, Patrick A
2018-06-22
Sulphation of carbohydrate residues occurs on a variety of glycans destined for secretion, and this modification is essential for efficient matrix-based signal transduction. Heparan sulphate (HS) glycosaminoglycans control physiological functions ranging from blood coagulation to cell proliferation. HS biosynthesis involves membrane-bound Golgi sulphotransferases, including heparan sulphate 2- O -sulphotransferase (HS2ST), which transfers sulphate from the co-factor PAPS (3'-phosphoadenosine 5'-phosphosulphate) to the 2- O position of a-L-iduronate in the maturing polysaccharide chain. The current lack of simple non-radioactive enzyme assays that can be used to quantify the levels of carbohydrate sulphation hampers kinetic analysis of this process and the discovery of HS2ST inhibitors. In this paper, we describe a new procedure for thermal shift analysis of purified HS2ST. Using this approach, we quantify HS2ST-catalyzed oligosaccharide sulphation using a novel synthetic fluorescent substrate and screen the Published Kinase Inhibitor Set (PKIS), to evaluate compounds that inhibit catalysis. We report the susceptibility of HS2ST to a variety of cell permeable compounds in vitro , including polyanionic polar molecules, the protein kinase inhibitor rottlerin and oxindole-based RAF kinase inhibitors. In a related study, published back-to-back with this article, we demonstrate that Tyrosyl Protein Sulpho Tranferases (TPSTs) are also inhibited by a variety of protein kinase inhibitors. We propose that appropriately validated small molecule compounds could become new tools for rapid inhibition of glycan (and protein) sulphation in cells, and that protein kinase inhibitors might be repurposed or redesigned for the specific inhibition of HS2ST. ©2018 The Author(s).
Synaptogenesis Is Modulated by Heparan Sulfate in Caenorhabditis elegans
Lázaro-Peña, María I.; Díaz-Balzac, Carlos A.; Bülow, Hannes E.; Emmons, Scott W.
2018-01-01
The nervous system regulates complex behaviors through a network of neurons interconnected by synapses. How specific synaptic connections are genetically determined is still unclear. Male mating is the most complex behavior in Caenorhabditis elegans. It is composed of sequential steps that are governed by > 3000 chemical connections. Here, we show that heparan sulfates (HS) play a role in the formation and function of the male neural network. HS, sulfated in position 3 by the HS modification enzyme HST-3.1/HS 3-O-sulfotransferase and attached to the HS proteoglycan glypicans LON-2/glypican and GPN-1/glypican, functions cell-autonomously and nonautonomously for response to hermaphrodite contact during mating. Loss of 3-O sulfation resulted in the presynaptic accumulation of RAB-3, a molecule that localizes to synaptic vesicles, and disrupted the formation of synapses in a component of the mating circuits. We also show that the neural cell adhesion protein NRX-1/neurexin promotes and the neural cell adhesion protein NLG-1/neuroligin inhibits the formation of the same set of synapses in a parallel pathway. Thus, neural cell adhesion proteins and extracellular matrix components act together in the formation of synaptic connections. PMID:29559501
DOE Office of Scientific and Technical Information (OSTI.GOV)
O'Donnell, Christopher D.; Department of Ophthalmology and Visual Sciences, College of Medicine, University of Illinois at Chicago, Chicago, IL 60612; Tiwari, Vaibhav
2006-03-15
Heparan sulfate (HS) 3-O-sulfotransferase isoform-2 (3-OST-2), which belongs to a family of enzymes capable of generating herpes simplex virus type-1 (HSV-1) entry and spread receptors, is predominantly expressed in human brain. Despite its unique expression pattern, the ability of 3-OST-2 to mediate HSV-1 entry and cell-to-cell fusion is not known. Our results demonstrate that expression of 3-OST-2 can render Chinese hamster ovary K1 (CHO-K1) cells susceptible to entry of wild-type and mutant strains of HSV-1. Evidence for generation of gD receptors by 3-OST-2 were suggested by gD-mediated interference assay and the ability of 3-OST-2-expressing CHO-K1 cells to preferentially bind HSV-1more » gD, which could be reversed by prior treatment of cells with HS lyases (heparinases II/III). In addition, 3-OST-2-expressing CHO-K1 cells acquired the ability to fuse with cells-expressing HSV-1 glycoproteins, a phenomenon that mimics a way of viral spread in vivo. Demonstrating specificity, the cell fusion was inhibited by soluble 3-O-sulfated forms of HS, but not unmodified HS. Taken together, our results raise the possibility of a role of 3-OST-2 in the spread of HSV-1 infection in the brain.« less
Proteoglycans in polarized epithelial Madin-Darby canine kidney cells.
Svennevig, K; Prydz, K; Kolset, S O
1995-01-01
Madin-Darby canine kidney (MDCK) cells were cultured on polycarbonate filters to study the synthesis and sorting of proteoglycans in polarized epithelial cells. Two strains of MDCK cells were used. MDCK I cells resemble distal tubule epithelial cells, and MDCK II cells share some characteristics with proximal tubule cells. Both strains were grown to confluency and labelled with [35S]sulphate for 24 h. The apical and basolateral media and the cell fractions were harvested and analysed by DEAE ion-exchange chromatography. A large portion of the [35S]sulphate-labelled macromolecules bound strongly to the ion-exchange columns, and could be eluted in three distinct peaks. The latest eluting peak was demonstrated to contain almost exclusively chondroitin sulphate, whereas peak 2 contained mostly heparan sulphate, demonstrated by using chondroitinase ABC and nitrous acid (pH 1.5) respectively to depolymerize the [35S]glycosaminoglycan chains. Peak 1 contained negligible amounts of proteoglycans. Large differences could be observed in proteoglycan sorting in MDCK I and II cells. Strain I secreted approx. 67% of the proteoglycans to the apical side and 17% to the basolateral side. The cell fraction contained 17% of the proteoglycans after 24 h of labelling. In contrast, 19% of the proteoglycans were sorted to the apical side of MDCK II cells and 61% to the basolateral side, whereas the cell fraction contained 20%. Furthermore, the level of [35S]proteoglycan biosynthesis (apical and basolateral media and cell fraction total) was higher in MDCK I cells than in strain II. Based on the amount of material degraded by chondroitinase ABC and nitrous acid respectively, and the total amounts of [35S]proteoglycans recovered from the cells, it was calculated that the MDCK I strain synthesized approx. 56% chondroitin sulphate and 44% heparan sulphate. In contrast, the MDCK II strain synthesized 69% heparan sulphate and 31% chondroitin sulphate. To further identify the [35S]proteoglycans synthesized by MDCK I and II cells, antibodies against perlecan, versican and syndecan were used. The antibody against mouse syndecan did not cross-react with any of the proteoglycans produced in MDCK I or II cells. Both MDCK I and II cells expressed perlecan; 57-61% could be recovered from the basolateral fractions and 18-34% from the apical medium. Versican was also found in both MDCK I and II cells. Compared with perlecan, a larger percentage of versican (43-53%) was found in the cell fractions. Images Figure 3 Figure 4 Figure 5 Figure 6 PMID:7487945
Shannon-Lowe, Claire; Rowe, Martin
2011-01-01
Epstein Barr virus (EBV) exhibits a distinct tropism for both B cells and epithelial cells. The virus persists as a latent infection of memory B cells in healthy individuals, but a role for infection of normal epithelial is also likely. Infection of B cells is initiated by the interaction of the major EBV glycoprotein gp350 with CD21 on the B cell surface. Fusion is triggered by the interaction of the EBV glycoprotein, gp42 with HLA class II, and is thereafter mediated by the core fusion complex, gH/gL/gp42. In contrast, direct infection of CD21-negative epithelial cells is inefficient, but efficient infection can be achieved by a process called transfer infection. In this study, we characterise the molecular interactions involved in the three stages of transfer infection of epithelial cells: (i) CD21-mediated co-capping of EBV and integrins on B cells, and activation of the adhesion molecules, (ii) conjugate formation between EBV-loaded B cells and epithelial cells via the capped adhesion molecules, and (iii) interaction of EBV glycoproteins with epithelial cells, with subsequent fusion and uptake of virions. Infection of epithelial cells required the EBV gH and gL glycoproteins, but not gp42. Using an in vitro model of normal polarized epithelia, we demonstrated that polarization of the EBV receptor(s) and adhesion molecules restricted transfer infection to the basolateral surface. Furthermore, the adhesions between EBV-loaded B cells and the basolateral surface of epithelial cells included CD11b on the B cell interacting with heparan sulphate moieties of CD44v3 and LEEP-CAM on epithelial cells. Consequently, transfer infection was efficiently mediated via CD11b-positive memory B cells but not by CD11b–negative naïve B cells. Together, these findings have important implications for understanding the mechanisms of EBV infection of normal and pre-malignant epithelial cells in vivo. PMID:21573183
Ziraksaz, Zarrintaj; Nomani, Alireza; Ruponen, Marika; Soleimani, Masoud; Tabbakhian, Majid; Haririan, Ismaeil
2013-01-23
Interaction of cell-surface glycosaminoglycans (GAGs) with non-viral vectors seems to be an important factor which modifies the intracellular destination of the gene complexes. Intracellular kinetics of polyamidoamine (PAMAM) dendrimer as a non-viral vector in cellular uptake, intranuclear delivery and transgene expression of plasmid DNA with regard to the cell-surface GAGs has not been investigated until now. The physicochemical properties of the PAMAM-pDNA complexes were characterized by photon correlation spectroscopy, atomic force microscopy, zeta measurement and agarose gel electrophoresis. The transfection efficiency and toxicity of the complexes at different nitrogen to phosphate (N:P) ratios were determined using various in vitro cell models such as human embryonic kidney cells, chinese hamster ovary cells and its mutants lacking cell-surface GAGs or heparan sulphate proteoglycans (HSPGs). Cellular uptake, nuclear uptake and transfection efficiency of the complexes were determined using flow cytometry and optimized cell-nuclei isolation with quantitative real-time PCR and luciferase assay. Physicochemical studies showed that PAMAM dendrimer binds pDNA efficiently, forms small complexes with high positive zeta potential and transfects cells properly at N:P ratios around 5 and higher. The cytotoxicity could be a problem at N:Ps higher than 10. GAGs elimination caused nearly one order of magnitude higher pDNA nuclear uptake and more than 2.6-fold higher transfection efficiency than CHO parent cells. However, neither AUC of nuclear uptake, nor AUC of transfection affected significantly by only cell-surface HSPGs elimination and interesting data related to the effect of GAGs on intranuclear pDNA using PAMAM as delivery vector have been reported in this study. Presented data shows that the rate-limiting step of PAMAM-pDNA complexes transfection is located after delivery to the cell nucleus and GAGs are regarded as an inhibitor of the intranuclear delivery step, while slightly promotes transgene expression. Copyright © 2012 Elsevier B.V. All rights reserved.
Gopinath, Subash C B; Hayashi, Kyoko; Lee, Jung-Bum; Kamori, Akiko; Dong, Cai-Xia; Hayashi, Toshimitsu; Kumar, Penmetcha K R
2013-11-05
The entry of herpes simplex virus into host cells involves a complex series of events that require concerted inputs from multiple HSV glycoproteins. Among these glycoproteins, the gD protein of HSV-1 and HSV-2 plays an important role for host receptor binding and membrane fusion. In the present study, we evaluated the ability of different sulfated saccharides to interfere with gD-host receptor (HVEM) interactions using our recently reported molecular assay (Gopinath, S. C. B.; Hayashi, K.; Kumar, P. K. R. J. Virol. 2012, 86, 6732-6744). Initially, we tested the ability of heparan sulfate to interfere with the HVEM-HSV-1 gD interaction and found that heparan sulfate is able to interfere efficiently, with an apparent EC50 of 2.1 μM. In addition, we tested different synthetic sulfated polysaccharides and natural sulfated polysaccharides from an edible alga, Sargassum horneri , after fractionation into different sizes and sulfate and uronic acid contents. Six polysaccharides isolated from S. horneri were found to efficiently interfere with the HVEM-gD interaction. Three others caused moderate interference, and five caused weak interference. These results were confirmed with plaque assays, and good agreement was found with the results of the SPR assay for the identification of compounds that interfere with HVEM-HSV-1 gD binding. These studies suggest that our molecular assay based on surface plasmon resonance is not only useful for the analysis of viral-host protein interactions but is also applicable for the routine screening of compounds to identify those that interfere with the first step of viral entry, thus facilitating the rapid development of novel antiviral compounds that target HSV.
Mozley, Olivia L; Thompson, Ben C; Fernandez-Martell, Alejandro; James, David C
2014-01-01
In this study, we examine the molecular and cellular interactions that underpin efficient internalization and utilization of polyethylenimine (PEI):DNA complexes (polyplexes) by Chinese Hamster Ovary (CHO) cells. Cell surface polyplex binding and internalization was a biphasic process, consisting of an initial rapid Phase (I), lasting approximately 15 min, followed by a slower second Phase (II), saturating at approximately 240 min post transfection. The second Phase accounted for the majority (60-70%) of polyplex internalization. While cell surface heparan sulphate proteoglycans (HSPGs) were rapidly cointernalized with polyplexes during Phase I, cell surface polyplex binding was not dependent on HSPGs. However, Phase II polyplex internalization and HSPG regeneration onto the surface of trypsinized cells occurred at similar rates, suggesting that the rate of recycling of HSPG-containing membrane to the plasma membrane limits Phase II internalization rate. Under optimal transfection conditions, polyplexes had a near neutral surface charge (zeta potential) and cell surface binding was dependent on hydrophobic interactions, being significantly inhibited by both chemical sequestration of cholesterol from the plasma membrane and addition of nonionic surfactant. Induced alterations in polyplex zeta potential, using ferric (III) citrate to decrease surface charge and varying PEI:DNA ratio to increase surface charge, served to inhibit polyplex binding or reduce secreted alkaline phosphatase reporter expression and cell viability, respectively. To increase polyplex hydrophobicity and internalization an alkylated derivative of PEI, propyl-PEI, was chemically synthesized. Using Design of Experiments-Response Surface Modeling to optimize the transfection process, the function of propyl-PEI was compared to that of unmodified PEI in both parental CHO-S cells and a subclone (Clone 4), which exhibited superior transgene expression via an increased resistance to polyplex cytotoxicity. The combination of propyl-PEI and Clone 4 doubled the efficiency of recombinant DNA utilization and reporter protein production. These data show that for maximal efficacy, strategies to increase polyplex internalization into cells must be used in concert with strategies to offset the inherent cytotoxicity of this process. © 2014 American Institute of Chemical Engineers.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Osawa, Sho; Department of Molecular and Cellular Neurobiology, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi, Gunma 371-8511; Kurachi, Masashi
We previously reported transplantation of brain microvascular endothelial cells (MVECs) into cerebral white matter infarction model improved the animal's behavioral outcome by increasing the number of oligodendrocyte precursor cells (OPCs). We also revealed extracellular vesicles (EVs) derived from MVECs promoted survival and proliferation of OPCs in vitro. In this study, we investigated the mechanism how EVs derived from MVECs contribute to OPC survival and proliferation. Protein mass spectrometry and enzyme-linked immunosorbent assay revealed fibronectin was abundant on the surface of EVs from MVECs. As fibronectin has been reported to promote OPC survival and proliferation via integrin signaling pathway, we blocked themore » binding between fibronectin and integrins using RGD sequence mimics. Blocking the binding, however, did not attenuate the survival and proliferation promoting effect of EVs on OPCs. Flow cytometric and imaging analyses revealed fibronectin on EVs mediates their internalization into OPCs by its binding to heparan sulfate proteoglycan on OPCs. OPC survival and proliferation promoted by EVs were attenuated by blocking the internalization of EVs into OPCs. These lines of evidence suggest that fibronectin on EVs mediates their internalization into OPCs, and the cargo of EVs promotes survival and proliferation of OPCs, independent of integrin signaling pathway. - Highlights: • Fibronectin exists on the surface of extracellular vesicles from endothelial cells. • Integrin signaling is not involved in effects of extracellular vesicles on OPCs. • Fibronectin on the surface of extracellular vesicles mediates their uptake into OPCs.« less
Zcharia, Eyal; Jia, Juan; Zhang, Xiao; Baraz, Lea; Lindahl, Ulf; Peretz, Tamar; Vlodavsky, Israel; Li, Jin-Ping
2009-01-01
Heparanase, a mammalian endo-beta-D-glucuronidase, specifically degrades heparan sulfate proteoglycans ubiquitously associated with the cell surface and extracellular matrix. This single gene encoded enzyme is over-expressed in most human cancers, promoting tumor metastasis and angiogenesis. We report that targeted disruption of the murine heparanase gene eliminated heparanase enzymatic activity, resulting in accumulation of long heparan sulfate chains. Unexpectedly, the heparanase knockout (Hpse-KO) mice were fertile, exhibited a normal life span and did not show prominent pathological alterations. The lack of major abnormalities is attributed to a marked elevation in the expression of matrix metalloproteinases, for example, MMP2 and MMP14 in the Hpse-KO liver and kidney. Co-regulation of heparanase and MMPs was also noted by a marked decrease in MMP (primarily MMP-2,-9 and 14) expression following transfection and over-expression of the heparanase gene in cultured human mammary carcinoma (MDA-MB-231) cells. Immunostaining (kidney tissue) and chromatin immunoprecipitation (ChIP) analysis (Hpse-KO mouse embryonic fibroblasts) suggest that the newly discovered co-regulation of heparanase and MMPs is mediated by stabilization and transcriptional activity of beta-catenin. The lack of heparanase expression and activity was accompanied by alterations in the expression level of MMP family members, primarily MMP-2 and MMP-14. It is conceivable that MMP-2 and MMP-14, which exert some of the effects elicited by heparanase (i.e., over branching of mammary glands, enhanced angiogenic response) can compensate for its absence, in spite of their different enzymatic substrate. Generation of viable Hpse-KO mice lacking significant abnormalities may provide a promising indication for the use of heparanase as a target for drug development.
Divergent Synthesis of Heparan Sulfate Oligosaccharides
2015-01-01
Heparan sulfates are implicated in a wide range of biological processes. A major challenge in deciphering their structure and activity relationship is the synthetic difficulties to access diverse heparan sulfate oligosaccharides with well-defined sulfation patterns. In order to expedite the synthesis, a divergent synthetic strategy was developed. By integrating chemical synthesis and two types of O-sulfo transferases, seven different hexasaccharides were obtained from a single hexasaccharide precursor. This approach combined the flexibility of chemical synthesis with the selectivity of enzyme-catalyzed sulfations, thus simplifying the overall synthetic operations. In an attempt to establish structure activity relationships of heparan sulfate binding with its receptor, the synthesized oligosaccharides were incorporated onto a glycan microarray, and their bindings with a growth factor FGF-2 were examined. The unique combination of chemical and enzymatic approaches expanded the capability of oligosaccharide synthesis. In addition, the well-defined heparan sulfate structures helped shine light on the fine substrate specificities of biosynthetic enzymes and confirm the potential sequence of enzymatic reactions in biosynthesis. PMID:26574650
Xuan, X; Maeda, K; Mikami, T; Otsuka, H
1996-12-01
The gene encoding the canine herpesvirus (CHV) glycoprotein C (gC) homologue has been identified by sequence homology analyses with other well studied herpesviruses. Previously, we have identified three CHV glycoproteins, gp145/112, gp80 and gp47 using a panel of monoclonal antibodies (MAbs). To determine which CHV glycoprotein corresponds to gC, a recombinant baculovirus which contains the putative CHV gC structural gene under the baculovirus polyhedrin promoter was constructed. The recombinant baculovirus expressed gC-related polypeptides (44-62 kDa), which reacted only with MAbs against CHV gp80, indicating that the previously identified CHV gp80 is the translation product of the gC gene. The baculovirus expressed gC was glycosylated and transported to the surface of infected cells. At least seven neutralizing epitopes were conserved on the gC produced in insect cells. It was found that the recombinant baculovirus infected cells adsorbed murine erythrocytes as is the case for CHV-infected cells. The hemadsorption activity was inhibited by heparin, indicating that the CHV gC binds to heparan sulfate on the surface of murine erythrocytes. Mice immunized with the recombinant gC produced strong neutralizing antibodies. Our results suggest that CHV gC produced in insect cells may be useful as a subunit vaccine to control CHV infections.
Kinnunen, Tarja K.
2014-01-01
Heparan sulfate proteoglycans (HSPGs) play critical roles in the development and adult physiology of all metazoan organisms. Most of the known molecular interactions of HSPGs are attributed to the structurally highly complex heparan sulfate (HS) glycans. However, whether a specific HSPG (such as syndecan) contains HS modifications that differ from another HSPG (such as glypican) has remained largely unresolved. Here, a neural model in C. elegans is used to demonstrate for the first time the relationship between specific HSPGs and HS modifications in a defined biological process in vivo. HSPGs are critical for the migration of hermaphrodite specific neurons (HSNs) as genetic elimination of multiple HSPGs leads to 80% defect of HSN migration. The effects of genetic elimination of HSPGs are additive, suggesting that multiple HSPGs, present in the migrating neuron and in the matrix, act in parallel to support neuron migration. Genetic analyses suggest that syndecan/sdn-1 and HS 6-O-sulfotransferase, hst-6, function in a linear signaling pathway and glypican/lon-2 and HS 2-O-sulfotransferase, hst-2, function together in a pathway that is parallel to sdn-1 and hst-6. These results suggest core protein specific HS modifications that are critical for HSN migration. In C. elegans, the core protein specificity of distinct HS modifications may be in part regulated at the level of tissue specific expression of genes encoding for HSPGs and HS modifying enzymes. Genetic analysis reveals that there is a delicate balance of HS modifications and eliminating one HS modifying enzyme in a compromised genetic background leads to significant changes in the overall phenotype. These findings are of importance with the view of HS as a critical regulator of cell signaling in normal development and disease. PMID:25054285
AMP; Dermatan sulfate - urine; Urine heparan sulfate; Urine dermatan sulfate; Heparan sulfate - urine ... the smaller special container and then transfer that urine into the other larger container. On day 1, ...
Bix, Gregory; Fu, Jian; Gonzalez, Eva M.; Macro, Laura; Barker, Amy; Campbell, Shelly; Zutter, Mary M.; Santoro, Samuel A.; Kim, Jiyeun K.; Höök, Magnus; Reed, Charles C.; Iozzo, Renato V.
2004-01-01
Endorepellin, the COOH-terminal domain of the heparan sulfate proteoglycan perlecan, inhibits several aspects of angiogenesis. We provide evidence for a novel biological axis that links a soluble fragment of perlecan protein core to the major cell surface receptor for collagen I, α2β1 integrin, and provide an initial investigation of the intracellular signaling events that lead to endorepellin antiangiogenic activity. The interaction between endorepellin and α2β1 integrin triggers a unique signaling pathway that causes an increase in the second messenger cAMP; activation of two proximal kinases, protein kinase A and focal adhesion kinase; transient activation of p38 mitogen-activated protein kinase and heat shock protein 27, followed by a rapid down-regulation of the latter two proteins; and ultimately disassembly of actin stress fibers and focal adhesions. The end result is a profound block of endothelial cell migration and angiogenesis. Because perlecan is present in both endothelial and smooth muscle cell basement membranes, proteolytic activity during the initial stages of angiogenesis could liberate antiangiogenic fragments from blood vessels' walls, including endorepellin. PMID:15240572
Kim, Aeyung; Shin, Tae-Hwan; Shin, Seung-Min; Pham, Chuong D; Choi, Dong-Ki; Kwon, Myung-Hee; Kim, Yong-Sung
2012-01-01
Cellular internalization of bacteriophage by surface-displayed cell penetrating peptides has been reported, though the underlying mechanism remains elusive. Here we describe in detail the internalization mechanism and intracellular trafficking and stability of filamentous M13 phages, the cellular entry of which is mediated by surface-displayed cell-penetrating light chain variable domain 3D8 VL transbody (3D8 VL-M13) or TAT peptide (TAT-M13). Recombinant 3D8 VL-M13 and TAT-M13 phages were efficiently internalized into living mammalian cells via physiologically relevant, energy-dependent endocytosis and were recovered from the cells in their infective form with the yield of 3D8 VL-M13 being higher (0.005 ≈ 0.01%) than that of TAT-M13 (0.001 ≈ 0.005%). Biochemical and genetic studies revealed that 3D8 VL-M13 was internalized principally by caveolae-mediated endocytosis via interaction with heparan sulfate proteoglycans as cell surface receptors, whereas TAT-M13 was internalized by clathrin- and caveolae-mediated endocytosis utilizing chondroitin sulfate proteoglycans as cell surface receptors, suggesting that phage internalization occurs by physiological endocytotic mechanism through specific cell surface receptors rather than non-specific transcytotic pathways. Internalized 3D8 VL-M13 phages routed to the cytosol and remained stable for more than 18 h without further trafficking to other subcellular compartments, whereas TAT-M13 phages routed to several subcellular compartments before being degraded in lysosomes even after 2 h of internalization. Our results suggest that the internalizing mechanism and intracellular trafficking of filamentous M13 bacteriophages largely follow the attributes of the displayed cell-penetrating moiety. Efficient internalization and cytosolic localization of 3D8 VL transbody-displayed phages will provide a useful tool for intracellular delivery of polar macromolecules such as proteins, peptides, and siRNAs.
Shin, Seung-Min; Pham, Chuong D.; Choi, Dong-Ki; Kwon, Myung-Hee; Kim, Yong-Sung
2012-01-01
Cellular internalization of bacteriophage by surface-displayed cell penetrating peptides has been reported, though the underlying mechanism remains elusive. Here we describe in detail the internalization mechanism and intracellular trafficking and stability of filamentous M13 phages, the cellular entry of which is mediated by surface-displayed cell-penetrating light chain variable domain 3D8 VL transbody (3D8 VL-M13) or TAT peptide (TAT-M13). Recombinant 3D8 VL-M13 and TAT-M13 phages were efficiently internalized into living mammalian cells via physiologically relevant, energy-dependent endocytosis and were recovered from the cells in their infective form with the yield of 3D8 VL-M13 being higher (0.005∼0.01%) than that of TAT-M13 (0.001∼0.005%). Biochemical and genetic studies revealed that 3D8 VL-M13 was internalized principally by caveolae-mediated endocytosis via interaction with heparan sulfate proteoglycans as cell surface receptors, whereas TAT-M13 was internalized by clathrin- and caveolae-mediated endocytosis utilizing chondroitin sulfate proteoglycans as cell surface receptors, suggesting that phage internalization occurs by physiological endocytotic mechanism through specific cell surface receptors rather than non-specific transcytotic pathways. Internalized 3D8 VL-M13 phages routed to the cytosol and remained stable for more than 18 h without further trafficking to other subcellular compartments, whereas TAT-M13 phages routed to several subcellular compartments before being degraded in lysosomes even after 2 h of internalization. Our results suggest that the internalizing mechanism and intracellular trafficking of filamentous M13 bacteriophages largely follow the attributes of the displayed cell-penetrating moiety. Efficient internalization and cytosolic localization of 3D8 VL transbody-displayed phages will provide a useful tool for intracellular delivery of polar macromolecules such as proteins, peptides, and siRNAs. PMID:23251631
Mizumoto, Shuji; Takahashi, Jun; Sugahara, Kazuyuki
2012-06-01
Altered expression of chondroitin sulfate (CS) and heparan sulfate (HS) at the surfaces of tumor cells plays a key role in malignant transformation and tumor metastasis. Previously we demonstrated that a Lewis lung carcinoma (LLC)-derived tumor cell line with high metastatic potential had a higher proportion of E-disaccharide units, GlcUA-GalNAc(4,6-O-disulfate), in CS chains than low metastatic LLC cells and that such CS chains are involved in the metastatic process. The metastasis was markedly inhibited by the pre-administration of CS-E from squid cartilage rich in E units or by preincubation with a phage display antibody specific for CS-E. However, the molecular mechanism of the inhibition remains to be investigated. In this study the receptor molecule for CS chains containing E-disaccharides expressed on LLC cells was revealed to be receptor for advanced glycation end products (RAGE), which is a member of the immunoglobulin superfamily predominantly expressed in the lung. Interestingly, RAGE bound strongly to not only E-disaccharide, but also HS-expressing LLC cells. Furthermore, the colonization of the lungs by LLC cells was effectively inhibited by the blocking of CS or HS chains at the tumor cell surface with an anti-RAGE antibody through intravenous injections in a dose-dependent manner. These results provide the clear evidence that RAGE is at least one of the critical receptors for CS and HS chains expressed at the tumor cell surface and involved in experimental lung metastasis and that CS/HS and RAGE are potential molecular targets in the treatment of pulmonary metastasis.
Dos Santos, Morgan; Michopoulou, Anna; André‐Frei, Valérie; Boulesteix, Sophie; Guicher, Christine; Dayan, Guila; Whitelock, John; Damour, Odile; Rousselle, Patricia
2016-01-01
The epidermis is continuously renewed by stem cell proliferation and differentiation. Basal keratinocytes append the dermal‐epidermal junction, a cell surface‐associated, extracellular matrix that provides structural support and influences their behaviour. It consists of laminins, type IV collagen, nidogens, and perlecan, which are necessary for tissue organization and structural integrity. Perlecan is a heparan sulfate proteoglycan known to be involved in keratinocyte survival and differentiation. Aging affects the dermal epidermal junction resulting in decreased contact with keratinocytes, thus impacting epidermal renewal and homeostasis. We found that perlecan expression decreased during chronological skin aging. Our in vitro studies revealed reduced perlecan transcript levels in aged keratinocytes. The production of in vitro skin models revealed that aged keratinocytes formed a thin and poorly organized epidermis. Supplementing these models with purified perlecan reversed the phenomenon allowing restoration of a well‐differentiated multi‐layered epithelium. Perlecan down‐regulation in cultured keratinocytes caused depletion of the cell population that expressed keratin 15. This phenomenon depended on the perlecan heparan sulphate moieties, which suggested the involvement of a growth factor. Finally, we found defects in keratin 15 expression in the epidermis of aging skin. This study highlighted a new role for perlecan in maintaining the self‐renewal capacity of basal keratinocytes. PMID:26996820
NASA Astrophysics Data System (ADS)
McCrea, Keith R.; Ward, Robert S.
2016-06-01
Removal of several drug-resistant bacteria from blood by affinity adsorption onto a heparin-functional media is reported. Heparin is a chemical analogue of heparan sulfate (HS) proteoglycans, found on transmembrane proteins of endothelial cells. Many blood-borne human pathogens, including bacteria, viruses, parasites, and fungi have been reported to target HS as an initial step in their pathogenesis. Here, we demonstrate the binding and removal of Methicillin-resistant Staphylococcus aureus (MRSA), Extended-Spectrum Betalactamase Klebsiella pneumoniae (ESBL), and two Carbapenem-resistant Enterobacteriaceae (both CRE Escherichia coli and CRE K. pneumoniae) using 300 μm polyethylene beads surface modified with end-point-attached heparin. Depending on the specific bacteria, the amount removed ranged between 39% (ESBL) and 99.9% (CRE). The total amount of bacteria adsorbed ranged between 2.8 × 105 and 8.6 × 105 colony forming units (CFU) per gram of adsorption media. Based on a polymicrobial challenge which showed no competitive binding, MRSA and CRE apparently utilize different binding sequences on the immobilized heparin ligand. Since the total circulating bacterial load during bacteremia seldom exceeds 5 × 105 CFUs, it appears possible to significantly reduce bacterial concentration in infected patients by multi-pass recirculation of their blood through a small extracorporeal affinity filter containing the heparin-functional adsorption media. This 'dialysis-like therapy' is expected to improve patient outcomes and reduce the cost of care, particularly when there are no anti-infective drugs available to treat the infection.
Mucopolysaccharidosis type III
... the enzymes needed to break down the heparan sulfate sugar chain are missing or defective. There are ... a large amount of a mucopolysaccharide called heparan sulfate in the urine. Other tests may include: Blood ...
Glypican Is a Modulator of Netrin-Mediated Axon Guidance
Blanchette, Cassandra R.; Perrat, Paola N.; Thackeray, Andrea; Bénard, Claire Y.
2015-01-01
Netrin is a key axon guidance cue that orients axon growth during neural circuit formation. However, the mechanisms regulating netrin and its receptors in the extracellular milieu are largely unknown. Here we demonstrate that in Caenorhabditis elegans, LON-2/glypican, a heparan sulfate proteoglycan, modulates UNC-6/netrin signaling and may do this through interactions with the UNC-40/DCC receptor. We show that developing axons misorient in the absence of LON-2/glypican when the SLT-1/slit guidance pathway is compromised and that LON-2/glypican functions in both the attractive and repulsive UNC-6/netrin pathways. We find that the core LON-2/glypican protein, lacking its heparan sulfate chains, and secreted forms of LON-2/glypican are functional in axon guidance. We also find that LON-2/glypican functions from the epidermal substrate cells to guide axons, and we provide evidence that LON-2/glypican associates with UNC-40/DCC receptor–expressing cells. We propose that LON-2/glypican acts as a modulator of UNC-40/DCC-mediated guidance to fine-tune axonal responses to UNC-6/netrin signals during migration. PMID:26148345
Heparan Sulfate Expression in the Neural Crest is Essential for Mouse Cardiogenesis
Pan, Yi; Carbe, Christian; Pickhinke, Ute; Kupich, Sabine; Ohlig, Stefanie; Frye, Maike; Seelige, Ruth; Pallerla, Srinivas R.; Moon, Anne M.; Lawrence, Roger; Esko, Jeffrey D.; Zhang, Xin; Grobe, Kay
2015-01-01
Impaired heparan sulfate (HS) synthesis in vertebrate development causes complex malformations due to the functional disruption of multiple HS-binding growth factors and morphogens. Here, we report developmental heart defects in mice bearing a targeted disruption of the HS-generating enzyme GlcNAc N-Deacetylase/GlcN N-Sulfotransferase 1 (NDST1), including ventricular septal defects (VSD), persistent truncus arteriosus (PTA), double outlet right ventricle (DORV), and retroesophageal right subclavian artery (RERSC). These defects closely resemble cardiac anomalies observed in mice made deficient in the cardiogenic regulator fibroblast growth factor 8 (FGF8). Consistent with this, we show that HS-dependent FGF8/FGF-receptor2C assembly and FGF8-dependent ERK-phosphorylation are strongly reduced in NDST1−/− embryonic cells and tissues. Moreover, WNT1-Cre/LoxP-mediated conditional targeting of NDST function in neural crest cells (NCCs) revealed that their impaired HS-dependent development contributes strongly to the observed cardiac defects. These findings raise the possibility that defects in HS biosynthesis may contribute to congenital heart defects in humans that represent the most common type of birth defect. PMID:24200809
Douet, V; Kerever, A; Arikawa-Hirasawa, E; Mercier, F
2013-04-01
Fractones are extracellular matrix structures that form a niche for neural stem cells and their immediate progeny in the subventricular zone of the lateral ventricle (SVZa), the primary neurogenic zone in the adult brain. We have previously shown that heparan sulphates (HS) associated with fractones bind fibroblast growth factor-2 (FGF-2), a powerful mitotic growth factor in the SVZa. Here, our objective was to determine whether the binding of FGF-2 to fractone-HS is implicated in the mechanism leading to cell proliferation in the SVZa. Heparitinase-1 was intracerebroventricularly injected with FGF-2 to N-desulfate HS proteoglycans and determine whether the loss of HS and of FGF-2 binding to fractones modifies FGF-2 effect on cell proliferation. We also examined in vivo the binding of Alexa-Fluor-FGF-2 in relationship with the location of HS immunoreactivity in the SVZa. Heparatinase-1 drastically reduced the stimulatory effect of FGF-2 on cell proliferation in the SVZa. Alexa-Fluor-FGF-2 binding was strictly co-localized with HS immunoreactivity in fractones and adjacent vascular basement membranes in the SVZa. Our results demonstrate that FGF-2 requires HS to stimulate cell proliferation in the SVZa and suggest that HS associated with fractones and vascular basement membranes are responsible for activating FGF-2. Therefore, fractones and vascular basement membranes may function as a HS niche to drive cell proliferation in the adult neurogenic zone. © 2013 Blackwell Publishing Ltd.
Proteoglycans and neuronal migration in the cerebral cortex during development and disease
Maeda, Nobuaki
2015-01-01
Chondroitin sulfate proteoglycans and heparan sulfate proteoglycans are major constituents of the extracellular matrix and the cell surface in the brain. Proteoglycans bind with many proteins including growth factors, chemokines, axon guidance molecules, and cell adhesion molecules through both the glycosaminoglycan and the core protein portions. The functions of proteoglycans are flexibly regulated due to the structural variability of glycosaminoglycans, which are generated by multiple glycosaminoglycan synthesis and modifying enzymes. Neuronal cell surface proteoglycans such as PTPζ, neuroglycan C and syndecan-3 function as direct receptors for heparin-binding growth factors that induce neuronal migration. The lectican family, secreted chondroitin sulfate proteoglycans, forms large aggregates with hyaluronic acid and tenascins, in which many signaling molecules and enzymes including matrix proteases are preserved. In the developing cerebrum, secreted chondroitin sulfate proteoglycans such as neurocan, versican and phosphacan are richly expressed in the areas that are strategically important for neuronal migration such as the striatum, marginal zone, subplate and subventricular zone in the neocortex. These proteoglycans may anchor various attractive and/or repulsive cues, regulating the migration routes of inhibitory neurons. Recent studies demonstrated that the genes encoding proteoglycan core proteins and glycosaminoglycan synthesis and modifying enzymes are associated with various psychiatric and intellectual disorders, which may be related to the defects of neuronal migration. PMID:25852466
Expanding the role of 3-O sulfated heparan sulfate in herpes simplex virus type-1 entry
DOE Office of Scientific and Technical Information (OSTI.GOV)
O'Donnell, Christopher D., E-mail: codonn3@uic.ed; Department of Microbiology and Immunology, College of Medicine, University of Illinois at Chicago, Chicago, IL 60612; Kovacs, Maria, E-mail: marcsika101@yahoo.co
2010-02-20
Heparan sulfate (HS) proteoglycans are commonly exploited by multiple viruses for initial attachment to host cells. Herpes simplex virus-1 (HSV-1) is unique because it can use HS for both attachment and penetration, provided specific binding sites for HSV-1 envelope glycoprotein gD are present. The interaction with gD is mediated by specific HS moieties or 3-O sulfated HS (3-OS HS), which are generated by all but one of the seven isoforms of 3-O sulfotransferases (3-OSTs). Here we demonstrate that several common experimental cell lines express unique sets of 3-OST isoforms. While the isoforms 3-OST-3, -5 and -6 were most commonly expressed,more » isoforms 3-OST-2 and -4 were undetectable in the cell lines examined. Since most cell lines expressed multiple 3-OST isoforms, we addressed the significance of 3-OS HS in HSV-1 entry by down-regulating 2-O-sulfation, a prerequisite for 3-OS HS formation, by knocking down 2-OST expression by RNA interference (RNAi). 2-OST knockdown was verified by reverse-transcriptase PCR and Western blot analysis, while 3-OS HS knockdown was verified by immunofluorescence. Cells showed a significant decrease in viral entry, suggesting an important role for 3-OS HS. Implicating 3-OS HS further, cells knocked down for 2-OST expression also demonstrated decreased cell-cell fusion when cocultivated with effector cells transfected with HSV-1 glycoproteins. Our findings suggest that 3-OS HS may play an important role in HSV-1 entry into many different cell lines.« less
Lanzi, Cinzia; Zaffaroni, Nadia; Cassinelli, Giuliana
2017-01-01
Targeting heparan sulfate proteoglycans (HSPGs) and enzymes involved in heparan sulfate (HS) chain editing is emerging as a new anticancer strategy. The involvement of HSPGs in tumor cell signaling, inflammation, angiogenesis and metastasis indicates that agents able to inhibit aberrant HSPG functions can potentially act as multitarget drugs affecting both tumor cell growth and the supportive boost provided by the microenvironment. Moreover, accumulating evidence supports that an altered expression or function of HSPGs, or of the complex enzyme system regulating their activities, can also depress the tumor response to anticancer treatments in several tumor types. Thereby, targeting HSPGs or HSPG modifying enzymes appears an appealing approach to enhance chemotherapy efficacy. A great deal of effort from academia and industry has led to the development of agents mimicking HS, and/or inhibiting HSPG modifying enzymes. Inhibitors of Sulf-2, an endosulfatase that edits the HS sulfation pattern, and inhibitors of heparanase, the endoglycosidase that produces functional HS fragments, appear particularly promising. In fact, a Sulf-2 inhibitor (OKN-007), and two heparanase inhibitors/HS mimics (roneparstat, PG545) are currently under early clinical investigation. In this review, we summarized preclinical studies in experimental tumor models of the main chemical classes of Sulf-2 and heparanase inhibitors. We described examples of different mechanisms through which heparanase and HSPGs, often in cooperation, may impact tumor sensitivity to various antitumor agents. Finally, we reported a few preclinical studies showing increased antitumor efficacy obtained with the use of candidate clinical HS mimics in combination regimens. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.
Yu, K C; Chen, W; Cooper, A D
2001-06-01
It has been proposed that in the liver, chylomicron remnants (lipoproteins carrying dietary lipid) may be sequestered before being internalized by hepatocytes. To study this, chylomicron remnants labeled with a fluorescent dye were perfused into isolated livers of LDL receptor-deficient (LDLR-deficient) mice (Ldlr(-/-)) and examined by confocal microscopy. In contrast to livers from normal mice, there was clustering of the chylomicron remnants on the cell surface in the space of DISSE: These remnant clusters colocalized with clusters of LDLR-related protein (LRP) and could be eliminated by low concentrations of receptor-associated protein, an inhibitor of LRP. When competed with ligands of heparan sulfate proteoglycans (HSPGs), the remnant clusters still appeared but were fewer in number, although syndecans (membrane HSPGs) colocalized with the remnant clusters. This suggests that the clustering of remnants is not dependent on syndecans but that the syndecans may modify the binding of remnants. These results establish that sequestration is a novel process, the clustering of remnants in the space of DISSE: The clustering involves remnants binding to the LRP, and this may be stabilized by binding with syndecans, eventually followed by endocytosis.
Lishko, Valeryi K.; Moreno, Benjamin; Podolnikova, Nataly P.; Ugarova, Tatiana P.
2016-01-01
LL-37, a cationic antimicrobial peptide, has numerous immune-modulating effects. However, the identity of a receptor(s) mediating the responses in immune cells remains uncertain. We have recently demonstrated that LL-37 interacts with the αMI-domain of integrin αMβ2 (Mac-1), a major receptor on the surface of myeloid cells, and induces a migratory response in Mac-1-expressing monocyte/macrophages as well as activation of Mac-1 on neutrophils. Here, we show that LL-37 and its C-terminal derivative supported strong adhesion of various Mac-1-expressing cells, including HEK293 cells stably transfected with Mac-1, human U937 monocytic cells and murine IC-21 macrophages. The cell adhesion to LL-37 was partially inhibited by specific Mac-1 antagonists, including mAb against the αM integrin subunit and neutrophil inhibitory factor, and completely blocked when anti-Mac-1 antibodies were combined with heparin, suggesting that cell surface heparan sulfate proteoglycans act cooperatively with integrin Mac-1. Coating both Gram-negative and Gram-positive bacteria with LL-37 significantly potentiated their phagocytosis by macrophages, and this process was blocked by a combination of anti-Mac-1 mAb and heparin. Furthermore, phagocytosis by wild-type murine peritoneal macrophages of LL-37-coated latex beads, a model of foreign surfaces, was several fold higher than that of untreated beads. By contrast, LL-37 failed to augment phagocytosis of beads by Mac-1-deficient macrophages. These results identify LL-37 as a novel ligand for integrin Mac-1 and demonstrate that the interaction between Mac-1 on macrophages and bacteria-bound LL-37 promotes phagocytosis. PMID:27990411
Identification of the heparin binding site on adeno-associated virus serotype 3B (AAV-3B)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lerch, Thomas F.; Chapman, Michael S., E-mail: chapmami@ohsu.edu
2012-02-05
Adeno-associated virus is a promising vector for gene therapy. In the current study, the binding site on AAV serotype 3B for the heparan sulfate proteoglycan (HSPG) receptor has been characterized. X-ray diffraction identified a disaccharide binding site at the most positively charged region on the virus surface. The contributions of basic amino acids at this and other sites were characterized using site-directed mutagenesis. Both heparin and cell binding are correlated to positive charge at the disaccharide binding site, and transduction is significantly decreased in AAV-3B vectors mutated at this site to reduce heparin binding. While the receptor attachment sites ofmore » AAV-3B and AAV-2 are both in the general vicinity of the viral spikes, the exact amino acids that participate in electrostatic interactions are distinct. Diversity in the mechanisms of cell attachment by AAV serotypes will be an important consideration for the rational design of improved gene therapy vectors.« less
Identification of the heparin binding site on adeno-associated virus serotype 3B (AAV-3B)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lerch, Thomas F.; Chapman, Michael S.
2012-05-24
Adeno-associated virus is a promising vector for gene therapy. In the current study, the binding site on AAV serotype 3B for the heparan sulfate proteoglycan (HSPG) receptor has been characterized. X-ray diffraction identified a disaccharide binding site at the most positively charged region on the virus surface. The contributions of basic amino acids at this and other sites were characterized using site-directed mutagenesis. Both heparin and cell binding are correlated to positive charge at the disaccharide binding site, and transduction is significantly decreased in AAV-3B vectors mutated at this site to reduce heparin binding. While the receptor attachment sites ofmore » AAV-3B and AAV-2 are both in the general vicinity of the viral spikes, the exact amino acids that participate in electrostatic interactions are distinct. Diversity in the mechanisms of cell attachment by AAV serotypes will be an important consideration for the rational design of improved gene therapy vectors.« less
Lopez-Quintero, Sandra V; Cancel, Limary M; Pierides, Alexis; Antonetti, David; Spray, David C; Tarbell, John M
2013-01-01
Diabetes mellitus is a risk factor for cardiovascular disease; however, the mechanisms through which diabetes impairs homeostasis of the vasculature have not been completely elucidated. The endothelium interacts with circulating blood through the surface glycocalyx layer, which serves as a mechanosensor/transducer of fluid shear forces leading to biomolecular responses. Atherosclerosis localizes typically in regions of low or disturbed shear stress, but in diabetics, the distribution is more diffuse, suggesting that there is a fundamental difference in the way cells sense shear forces. In the present study, we examined the effect of hyperglycemia on mechanotranduction in bovine aortic endothelial cells (BAEC). After six days in high glucose media, we observed a decrease in heparan sulfate content coincident with a significant attenuation of the shear-induced hydraulic conductivity response, lower activation of eNOS after exposure to shear, and reduced cell alignment with shear stress. These studies are consistent with a diabetes-induced change to the glycocalyx altering endothelial response to shear stress that could affect the distribution of atherosclerotic plaques.
Lopez-Quintero, Sandra V.; Cancel, Limary M.; Pierides, Alexis; Antonetti, David; Spray, David C.; Tarbell, John M.
2013-01-01
Diabetes mellitus is a risk factor for cardiovascular disease; however, the mechanisms through which diabetes impairs homeostasis of the vasculature have not been completely elucidated. The endothelium interacts with circulating blood through the surface glycocalyx layer, which serves as a mechanosensor/transducer of fluid shear forces leading to biomolecular responses. Atherosclerosis localizes typically in regions of low or disturbed shear stress, but in diabetics, the distribution is more diffuse, suggesting that there is a fundamental difference in the way cells sense shear forces. In the present study, we examined the effect of hyperglycemia on mechanotranduction in bovine aortic endothelial cells (BAEC). After six days in high glucose media, we observed a decrease in heparan sulfate content coincident with a significant attenuation of the shear-induced hydraulic conductivity response, lower activation of eNOS after exposure to shear, and reduced cell alignment with shear stress. These studies are consistent with a diabetes-induced change to the glycocalyx altering endothelial response to shear stress that could affect the distribution of atherosclerotic plaques. PMID:24260138
Astudillo, Pablo; Carrasco, Héctor; Larraín, Juan
2014-01-01
Regulation of Wnt signaling is crucial for embryonic development and adult homeostasis. Here we study the role of Syndecan-4 (SDC4), a cell-surface heparan sulphate proteoglycan, and Fibronectin (FN), in Wnt/β-catenin signaling. Gain- and loss-of-function experiments in mammalian cell lines and Xenopus embryos demonstrate that SDC4 and FN inhibit Wnt/β-catenin signaling. Epistatic and biochemical experiments show that this inhibition occurs at the cell membrane level through regulation of LRP6. R-spondin 3, a ligand that promotes canonical and non-canonical Wnt signaling, is more prone to potentiate Wnt/β-catenin signaling when SDC4 levels are reduced, suggesting a model whereby SDC4 tunes the ability of R-spondin to modulate the different Wnt signaling pathways. Since SDC4 has been previously related to non-canonical Wnt signaling, our results also suggest that this proteoglycan can be a key component in the regulation of Wnt signaling. Copyright © 2013 Elsevier Ltd. All rights reserved.
Specific PET Imaging Probes for Early Detection of Prostate Cancer Metastases
2012-05-01
protamin sulfate and pentosan sulfate are more potent than heparan sulfate and chondroitin sulfates to inhibit FITC-R11 uptake. 2. In vitro and in...GAGs) on the uptake of FITC-R9, FITC- R11 and FITC-R13 have been evaluated in four prostate cancer cell lines. The results show that dextran sulfate
Persson, Andrea; Tykesson, Emil; Westergren-Thorsson, Gunilla; Malmström, Anders; Ellervik, Ulf; Mani, Katrin
2016-07-08
We previously reported that the xyloside 2-(6-hydroxynaphthyl) β-d-xylopyranoside (XylNapOH), in contrast to 2-naphthyl β-d-xylopyranoside (XylNap), specifically reduces tumor growth both in vitro and in vivo Although there are indications that this could be mediated by the xyloside-primed glycosaminoglycans (GAGs) and that these differ in composition depending on xyloside and cell type, detailed knowledge regarding a structure-function relationship is lacking. In this study we isolated XylNapOH- and XylNap-primed GAGs from a breast carcinoma cell line, HCC70, and a breast fibroblast cell line, CCD-1095Sk, and demonstrated that both XylNapOH- and XylNap-primed chondroitin sulfate/dermatan sulfate GAGs derived from HCC70 cells had a cytotoxic effect on HCC70 cells and CCD-1095Sk cells. The cytotoxic effect appeared to be mediated by induction of apoptosis and was inhibited in a concentration-dependent manner by the XylNap-primed heparan sulfate GAGs. In contrast, neither the chondroitin sulfate/dermatan sulfate nor the heparan sulfate derived from CCD-1095Sk cells primed on XylNapOH or XylNap had any effect on the growth of HCC70 cells or CCD-105Sk cells. These observations were related to the disaccharide composition of the XylNapOH- and XylNap-primed GAGs, which differed between the two cell lines but was similar when the GAGs were derived from the same cell line. To our knowledge this is the first report on cytotoxic effects mediated by chondroitin sulfate/dermatan sulfate. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.
Pre-clinical and clinical significance of heparanase in Ewing’s sarcoma
Shafat, Itay; Ben-Arush, Myriam Weyl; Issakov, Josephine; Meller, Isaac; Naroditsky, Inna; Tortoreto, Monica; Cassinelli, Giuliana; Lanzi, Cinzia; Pisano, Claudio; Ilan, Neta; Vlodavsky, Israel; Zunino, Franco
2011-01-01
Abstract Heparanase is an endoglycosidase that specifically cleaves heparan sulphate side chains of heparan sulphate proteoglycans, activity that is strongly implicated in cell migration and invasion associated with tumour metastasis, angiogenesis and inflammation. Heparanase up-regulation was documented in an increasing number of human carcinomas, correlating with reduced post-operative survival rate and enhanced tumour angiogenesis. Expression and significance of heparanase in human sarcomas has not been so far reported. Here, we applied the Ewing’s sarcoma cell line TC71 and demonstrated a potent inhibition of cell invasion in vitro and tumour xenograft growth in vivo upon treatment with a specific inhibitor of heparanase enzymatic activity (compound SST0001, non-anticoagulant N-acetylated, glycol split heparin). Next, we examined heparanase expression and cellular localization by immunostaining of a cohort of 69 patients diagnosed with Ewing’s sarcoma. Heparanase staining was noted in all patients. Notably, heparanase staining intensity correlated with increased tumour size (P = 0.04) and with patients’ age (P = 0.03), two prognostic factors associated with a worse outcome. Our study indicates that heparanase expression is induced in Ewing’s sarcoma and associates with poor prognosis. Moreover, it encourages the inclusion of heparanase inhibitors (i.e. SST0001) in newly developed therapeutic modalities directed against Ewing’s sarcoma and likely other malignancies. PMID:21029368
Gleitz, Hélène Fe; Liao, Ai Yin; Cook, James R; Rowlston, Samuel F; Forte, Gabriella Ma; D'Souza, Zelpha; O'Leary, Claire; Holley, Rebecca J; Bigger, Brian W
2018-06-08
The pediatric lysosomal storage disorder mucopolysaccharidosis type II is caused by mutations in IDS, resulting in accumulation of heparan and dermatan sulfate, causing severe neurodegeneration, skeletal disease, and cardiorespiratory disease. Most patients manifest with cognitive symptoms, which cannot be treated with enzyme replacement therapy, as native IDS does not cross the blood-brain barrier. We tested a brain-targeted hematopoietic stem cell gene therapy approach using lentiviral IDS fused to ApoEII (IDS.ApoEII) compared to a lentivirus expressing normal IDS or a normal bone marrow transplant. In mucopolysaccharidosis II mice, all treatments corrected peripheral disease, but only IDS.ApoEII mediated complete normalization of brain pathology and behavior, providing significantly enhanced correction compared to IDS. A normal bone marrow transplant achieved no brain correction. Whilst corrected macrophages traffic to the brain, secreting IDS/IDS.ApoEII enzyme for cross-correction, IDS.ApoEII was additionally more active in plasma and was taken up and transcytosed across brain endothelia significantly better than IDS via both heparan sulfate/ApoE-dependent receptors and mannose-6-phosphate receptors. Brain-targeted hematopoietic stem cell gene therapy provides a promising therapy for MPS II patients. © 2018 The Authors. Published under the terms of the CC BY 4.0 license.
Iwao, Keiichiro; Inatani, Masaru; Matsumoto, Yoshihiro; Ogata-Iwao, Minako; Takihara, Yuji; Irie, Fumitoshi; Yamaguchi, Yu; Okinami, Satoshi; Tanihara, Hidenobu
2009-01-01
During human embryogenesis, neural crest cells migrate to the anterior chamber of the eye and then differentiate into the inner layers of the cornea, the iridocorneal angle, and the anterior portion of the iris. When proper development does not occur, this causes iridocorneal angle dysgenesis and intraocular pressure (IOP) elevation, which ultimately results in developmental glaucoma. Here, we show that heparan sulfate (HS) deficiency in mouse neural crest cells causes anterior chamber dysgenesis, including corneal endothelium defects, corneal stroma hypoplasia, and iridocorneal angle dysgenesis. These dysfunctions are phenotypes of the human developmental glaucoma, Peters anomaly. In the neural crest cells of mice embryos, disruption of the gene encoding exostosin 1 (Ext1), which is an indispensable enzyme for HS synthesis, resulted in disturbed TGF-β2 signaling. This led to reduced phosphorylation of Smad2 and downregulated expression of forkhead box C1 (Foxc1) and paired-like homeodomain transcription factor 2 (Pitx2), transcription factors that have been identified as the causative genes for developmental glaucoma. Furthermore, impaired interactions between HS and TGF-β2 induced developmental glaucoma, which was manifested as an IOP elevation caused by iridocorneal angle dysgenesis. These findings suggest that HS is necessary for neural crest cells to form the anterior chamber via TGF-β2 signaling. Disturbances of HS synthesis might therefore contribute to the pathology of developmental glaucoma. PMID:19509472
Salton, S R; Margolis, R U; Margolis, R K
1983-10-01
Cultured PC12 pheochromocytoma cells were labeled with [3H]glucosamine, and the glycoproteins and proteoglycans released following potassium-induced depolarization were fractionated and characterized. Exposure of PC12 cells for 20 min to a high concentration of potassium (51.5 mM in Krebs-Ringers-HEPES buffer) results in an approximately sixfold increase in the release of labeled glycoproteins and proteoglycans, compared to incubation in physiological levels of potassium (6 mM). The released complex carbohydrates include chromogranins, dopamine beta-hydroxylase, and two chondroitin sulfate/heparan sulfate proteoglycan fractions, which together account for 7.4% of the soluble cell radioactivity. The chromogranins contained galactosyl(beta 1 leads to 3)N-acetylgalactosamine, as well as several mono- and disialyl O-glycosidically-linked oligosaccharides, and the tetrasaccharide AcNeu(alpha 2 leads to 3)Gal(beta 1 leads to 3)[AcNeu(alpha 2 leads to 6)] GalNAcol, obtained by alkaline borohydride treatment of the chromogranin glycopeptides, accounted for almost half of the total chromogranin labeling. The proteoglycan fractions varied in their relative proportions of chondroitin sulfate (23-68%), heparan sulfate (16-23%), and glycoprotein oligosaccharides (16-54%), which are of the tri- and tetraantennary and O-glycosidic types. As previously found in the case of proteoglycans from bovine chromaffin granules, the more acidic species has a considerably higher proportion of carbohydrate in the form of sulfated glycosaminoglycans.
Nucleolin is a nuclear target of heparan sulfate derived from glypican-1
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cheng, Fang; Belting, Mattias; Fransson, Lars-Åke
The recycling, S-nitrosylated heparan sulfate (HS) proteoglycan glypican-1 releases anhydromannose (anMan)-containing HS chains by a nitrosothiol-catalyzed cleavage in endosomes that can be constitutive or induced by ascorbate. The HS-anMan chains are then transported to the nucleus. A specific nuclear target for HS-anMan has not been identified. We have monitored endosome-to-nucleus trafficking of HS-anMan by deconvolution and confocal immunofluorescence microscopy using an anMan-specific monoclonal antibody in non-growing, ascorbate-treated, and growing, untreated, wild-type mouse embryonic fibroblasts and hypoxia-exposed Alzheimer mouse Tg2576 fibroblasts and human U87 glioblastoma cells. In all cells, nuclear HS-anMan targeted a limited number of sites of variable size wheremore » it colocalized with DNA and nucleolin, an established marker for nucleoli. HS-anMan also colocalized with ethynyl uridine-tagged nascent RNA and two acetylated forms of histone H3. Acute hypoxia increased the formation of HS-anMan in both Tg2576 and U87 cells. A portion of HS-anMan colocalized with nucleolin at small discrete sites, while most of the nucleolin and nascent RNA was dispersed. In U87 cells, HS-anMan, nucleolin and nascent RNA reassembled after prolonged hypoxia. Nucleolar HS may modulate synthesis and/or release of rRNA.« less
Papakonstantinou, Eleni; Klagas, Ioannis; Roth, Michael; Tamm, Michael; Stolz, Daiana
2016-03-01
Acute exacerbations of COPD (AECOPDs) are associated with accelerated aggravation of clinical symptoms and deterioration of pulmonary function. The mechanisms by which exacerbations may contribute to airway remodeling and declined lung function are poorly understood. We investigated whether AECOPDs are associated with differential expression of glycosaminoglycans in BAL in a cohort of 97 patients with COPD. Patients with COPD with either stable disease (n = 53) or AECOPD (n = 44) and undergoing diagnostic bronchoscopy were matched for demographics and lung function parameters. Levels of heparan sulfate, chondroitin sulfate, dermatan sulfate, and matrix metalloproteinases (MMPs) in BAL were measured by enzyme-linked immunosorbent assay. Heparan sulfate and chondroitin sulfate were significantly increased in BAL of patients during exacerbations. Levels of heparan sulfate were higher in the BAL of patients with microbial infections. Chondroitin sulfate was negatively correlated with FEV1 % predicted but not with diffusing capacity of lung for carbon monoxide % predicted, indicating that chondroitin sulfate is associated with airway remodeling, leading to obstruction rather than to emphysema. Furthermore, heparan sulfate and chondroitin sulfate were significantly correlated with MMP-9, MMP-2, and MMP-12 in BAL, indicating that they were cleaved from their respective proteoglycans by MMPs and subsequently washed out in BAL. During AECOPD, there is increased expression of heparan sulfate and chondroitin sulfate in BAL. These molecules are significantly correlated with MMPs in BAL, indicating that they may be associated with airway remodeling and may lead to lung function decline during exacerbations of COPD. Copyright © 2016 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.
Evaluation of glycosaminoglycans and heparanase in placentas of women with preeclampsia.
Famá, Eduardo Augusto Brosco; Souza, Renan Salvioni; Melo, Carina Mucciolo; Melo Pompei, Luciano; Pinhal, Maria Aparecida Silva
2014-11-01
Preeclampsia is a multisystem disorder whose etiology remains unclear. It is already known that circulation of soluble fms-like tyrosine kinase-1 (sFlt-1) is directly involved in pre-eclampsia development. However, the molecular mechanisms involved with sFlt-1 shedding are still unidentified. We identified, quantified glycosaminoglycans and determined the enzymatic activity of heparanase in placentas of women with preeclampsia, in order to possibly explain if these compounds could be related to cellular processes involved with preeclampsia. A total of 45 samples collected from placentas, 15 samples from placentas of preeclampsia women and 30 samples from non-affected women. Heparan sulfate and dermatan sulfate were identified and quantified by agarose gel electrophoresis, whilst hyaluronic acid was quantified by an ELISA like assay. Heparanase activity was determined using biotynilated heparan sulfate as substrate. The results showed that dermatan sulfate (P=0.019), heparan sulfate levels (P=0.015) and heparanase activity (P=0.006) in preeclampsia were significantly higher than in the control group. There was no significant difference between the groups for hyaluronic acid expression in placentas (P=0.110). The present study is the first to demonstrate directly the increase of heparan sulfate in human placentas from patients with preeclampsia, suggesting that endogenous heparan sulfate could be involved in the release of sFlt-1 from placenta, increasing the level of circulating sFlt-1. Alterations of extracellular matrix components in placentas with preeclampsia raise the possibility that heparan sulfate released by heparanase is involved in mechanisms of preeclampsia development. Published by Elsevier B.V.
van der Voort, R; Keehnen, R M; Beuling, E A; Spaargaren, M; Pals, S T
2000-10-16
Recently, biochemical, cell biological, and genetic studies have converged to reveal that integral membrane heparan sulfate proteoglycans (HSPGs) are critical regulators of growth and differentiation of epithelial and connective tissues. As a large number of cytokines involved in lymphoid tissue homeostasis or inflammation contain potential HS-binding domains, HSPGs presumably also play important roles in the regulation of the immune response. In this report, we explored the expression, regulation, and function of HSPGs on B lymphocytes. We demonstrate that activation of the B cell antigen receptor (BCR) and/or CD40 induces a strong transient expression of HSPGs on human tonsillar B cells. By means of these HSPGs, the activated B cells can bind hepatocyte growth factor (HGF), a cytokine that regulates integrin-mediated B cell adhesion and migration. This interaction with HGF is highly selective since the HSPGs did not bind the chemokine stromal cell-derived factor (SDF)-1 alpha, even though the affinities of HGF and SDF-1alpha for heparin are similar. On the activated B cells, we observed induction of a specific HSPG isoform of CD44 (CD44-HS), but not of other HSPGs such as syndecans or glypican-1. Interestingly, the expression of CD44-HS on B cells strongly promotes HGF-induced signaling, resulting in an HS-dependent enhanced phosphorylation of Met, the receptor tyrosine kinase for HGF, as well as downstream signaling molecules including Grb2-associated binder 1 (Gab1) and Akt/protein kinase B (PKB). Our results demonstrate that the BCR and CD40 control the expression of HSPGs, specifically CD44-HS. These HSPGs act as functional coreceptors that selectively promote cytokine signaling in B cells, suggesting a dynamic role for HSPGs in antigen-specific B cell differentiation.
El Najjar, Farah; Cifuentes-Muñoz, Nicolás; Zhu, Haining; Buchholz, Ursula J.; Moncman, Carole L.; Dutch, Rebecca Ellis
2016-01-01
Paramyxovirus spread generally involves assembly of individual viral particles which then infect target cells. We show that infection of human bronchial airway cells with human metapneumovirus (HMPV), a recently identified paramyxovirus which causes significant respiratory disease, results in formation of intercellular extensions and extensive networks of branched cell-associated filaments. Formation of these structures is dependent on actin, but not microtubule, polymerization. Interestingly, using a co-culture assay we show that conditions which block regular infection by HMPV particles, including addition of neutralizing antibodies or removal of cell surface heparan sulfate, did not prevent viral spread from infected to new target cells. In contrast, inhibition of actin polymerization or alterations to Rho GTPase signaling pathways significantly decreased cell-to-cell spread. Furthermore, viral proteins and viral RNA were detected in intercellular extensions, suggesting direct transfer of viral genetic material to new target cells. While roles for paramyxovirus matrix and fusion proteins in membrane deformation have been previously demonstrated, we show that the HMPV phosphoprotein extensively co-localized with actin and induced formation of cellular extensions when transiently expressed, supporting a new model in which a paramyxovirus phosphoprotein is a key player in assembly and spread. Our results reveal a novel mechanism for HMPV direct cell-to-cell spread and provide insights into dissemination of respiratory viruses. PMID:27683250
ROBUSTNESS OF SIGNALING GRADIENT IN DROSOPHILA WING IMAGINAL DISC
Lei, Jinzhi; Wan, Frederic Y. M.; Lander, Arthur D.; Nie, Qing
2012-01-01
Quasi-stable gradients of signaling protein molecules (known as morphogens or ligands) bound to cell receptors are known to be responsible for differential cell signaling and gene expressions. From these follow different stable cell fates and visually patterned tissues in biological development. Recent studies have shown that the relevant basic biological processes yield gradients that are sensitive to small changes in system characteristics (such as expression level of morphogens or receptors) or environmental conditions (such as temperature changes). Additional biological activities must play an important role in the high level of robustness observed in embryonic patterning for example. It is natural to attribute observed robustness to various type of feedback control mechanisms. However, our own simulation studies have shown that feedback control is neither necessary nor sufficient for robustness of the morphogen decapentaplegic (Dpp) gradient in wing imaginal disc of Drosophilas. Furthermore, robustness can be achieved by substantial binding of the signaling morphogen Dpp with nonsignaling cell surface bound molecules (such as heparan sulfate proteoglygans) and degrading the resulting complexes at a sufficiently rapid rate. The present work provides a theoretical basis for the results of our numerical simulation studies. PMID:24098092
Vanhaverbeke, Cécile; Simorre, Jean-Pierre; Sadir, Rabia; Gans, Pierre; Lortat-Jacob, Hugues
2004-01-01
Interferons are cytokines that play a complex role in the resistance of mammalian hosts to pathogens. IFNγ (interferon-γ) is secreted by activated T-cells and natural killer cells. IFNγ is involved in a wide range of physiological processes, including antiviral activity, immune response, cell proliferation and apoptosis, as well as the stimulation and repression of a variety of genes. IFNγ activity is modulated by the binding of its C-terminal domain to HS (heparan sulphate), a glycosaminoglycan found in the extracellular matrix and at the cell surface. In the present study, we analysed the interaction of isolated heparin-derived oligosaccharides with the C-terminal peptide of IFNγ by NMR, in aqueous solution. We observed marked changes in the chemical shifts of both peptide and oligosaccharide compared with the free state. Our results provide evidence of a binding through electrostatic interactions between the charged side chains of the protein and the sulphate groups of heparin that does not induce specific conformation of the C-terminal part of IFNγ. Our data also indicate that an oligosaccharide size of at least eight residues displays the most efficient binding. PMID:15270718
García, Beatriz; Merayo-Lloves, Jesús; Rodríguez, David; Alcalde, Ignacio; García-Suárez, Olivia; Alfonso, José F.; Baamonde, Begoña; Fernández-Vega, Andrés; Vazquez, Fernando; Quirós, Luis M.
2016-01-01
The epithelium of the cornea is continuously exposed to pathogens, and adhesion to epithelial cells is regarded as an essential first step in bacterial pathogenesis. In this article, the involvement of glycosaminoglycans in the adhesion of various pathogenic bacteria to corneal epithelial cells is analyzed. All microorganisms use glycosaminoglycans as receptors, but arranged in different patterns depending on the Gram-type of the bacterium. The heparan sulfate chains of syndecans are the main receptors, though other molecular species also seem to be involved, particularly in Gram-negative bacteria. Adherence is inhibited differentially by peptides, including heparin binding sequences, indicating the participation of various groups of Gram-positive, and -negative adhesins. The length of the saccharides produces a major effect, and low molecular weight chains inhibit the binding of Gram-negative microorganisms but increase the adherence of Gram-positives. Pathogen adhesion appears to occur preferentially through sulfated domains, and is very dependent on N- and 6-O-sulfation of the glucosamine residue and, to a lesser extent, 2-O sulfation of uronic acid. These data show the differential use of corneal receptors, which could facilitate the development of new anti-infective strategies. PMID:27965938
Ramnath, Raina; Foster, Rebecca R; Qiu, Yan; Cope, George; Butler, Matthew J; Salmon, Andrew H; Mathieson, Peter W; Coward, Richard J; Welsh, Gavin I; Satchell, Simon C
2014-11-01
The endothelial surface glycocalyx is a hydrated mesh in which proteoglycans are prominent. It is damaged in diseases associated with elevated levels of tumor necrosis factor α (TNF-α). We investigated the mechanism of TNF-α-induced disruption of the glomerular endothelial glycocalyx. We used conditionally immortalized human glomerular endothelial cells (GEnCs), quantitative PCR arrays, Western blotting, immunoprecipitation, immunofluorescence, and dot blots to examine the effects of TNF-α. TNF-α induced syndecan 4 (SDC4) mRNA up-regulation by 2.5-fold, whereas cell surface SDC4 and heparan sulfate (HS) were reduced by 36 and 30%, respectively, and SDC4 and sulfated glycosaminoglycan in the culture medium were increased by 52 and 65%, respectively, indicating TNF-α-induced shedding. Small interfering (siRNA) knockdown of SDC4 (by 52%) caused a corresponding loss of cell surface HS of similar magnitude (38%), and immunoprecipitation demonstrated that SDC4 and HS are shed as intact proteoglycan ectodomains. All of the effects of TNF-α on SDC4 and HS were abrogated by the metalloproteinase (MMP) inhibitor batimastat. Also abrogated was the associated 37% increase in albumin passage across GEnC monolayers. Specific MMP9 knockdown by siRNA similarly blocked TNF-α effects. SDC4 is the predominant HS proteoglycan in the GEnC glycocalyx. TNF-α-induced MMP9-mediated shedding of SDC4 is likely to contribute to the endothelial glycocalyx disruption observed in diabetes and inflammatory states. © FASEB.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wijk, Xander M.R. van; Oosterhof, Arie; Broek, Sebastiaan A.M.W. van den
2010-09-10
Heparan sulphate (HS) is a long, linear polysaccharide, which has a basic backbone of -{beta}1-4GlcA-{alpha}1-4GlcNAc- units. The involvement of HS in many steps of tumourigenesis, including growth and angiogenesis, makes it an appealing target for cancer therapy. To target the biosynthesis of HS by interfering with its chain elongation, a 4-deoxy analogue of N-acetyl-D-glucosamine (4-deoxy-GlcNAc) was synthesized. Using immunocytochemistry and agarose gel electrophoresis it was shown that incubation with the 4-deoxysugar resulted in a dose dependent reduction of HS expression of MV3 melanoma cells, 1 mM resulting in an almost nullified HS expression. The parent sugar GlcNAc had no effect.more » 4-deoxysugar treated cells were viable and proliferated at the same rate as control cells. Other glycan structures appeared to be only mildly affected, as staining by various lectins was generally not or only modestly inhibited. At 1 mM of the 4-deoxysugar, the capacity of cells to bind the HS-dependent pro-angiogenic growth factors FGF-2 and VEGF was greatly compromised. Using an in vitro angiogenesis assay, 4-deoxysugar treated endothelial cells showed a sharp reduction of FGF-2-induced sprout formation. Combined, these data indicate that an inexpensive, easily synthesized, water-soluble monosaccharide analogue can interfere with HS expression and pro-angiogenic growth factor binding.« less
NASA Astrophysics Data System (ADS)
Kundu, Soumi; Xiong, Anqi; Forsberg-Nilsson, Karin
2016-04-01
Heparan sulfate (HS) proteoglycans (HSPG) are major components of the extracellular matrix. They interact with a plethora of macromolecules that are of physiological importance. The pattern of sulfation of the HS chain determines the specificity of these interactions. The enzymes that synthesize and degrade HS are thus key regulators of processes ranging from embryonic development to tissue homeostasis and tumor development. Formation of the nervous system is also critically dependent on appropriate HSPGs as shown by several studies on the role of HS in neural induction from embryonic stem cells. High-grade glioma is the most common primary malignant brain tumor among adults, and the prognosis is poor. Neural and glioma stem cells share several traits, including sustained proliferation and highly efficient migration in the brain. There are also similarities between the neurogenic niche where adult neural stem cells reside and the tumorigenic niche, including their interactions with components of the extracellular matrix (ECM). The levels of many of these components, for example HSPGs and enzymes involved in the biosynthesis and modification of HS are attenuated in gliomas. In this paper, HS regulation of pathways involved in neural differentiation and how these may be of importance for brain development are discussed. The literature suggesting that modifications of HS could regulate glioma growth and invasion is reviewed. Targeting the invasiveness of glioma cells by modulating HS may improve upon present therapeutic options, which only marginally enhance the survival of glioma patients.
Cheng, Shi-Bin; Graeber, Carl T; Quinn, Jeffrey A; Filardo, Edward J
2011-08-01
G-protein-coupled receptor 30 (GPR30/GPER) belongs to the seven transmembrane receptor (7TMR) superfamily, the most common class of surface receptor with approximately 800 known members. GPER promotes estrogen binding and rapid signaling via membrane-associated enzymes resulting in increased cAMP and release of heparan bound epidermal growth factor (proHB-EGF) from breast cancer cells. However, GPER is predominately localized intracellularly in breast cancer cells with minor amounts of receptor on the cell surface, an observation that has caused some controversy regarding its potential role as a plasma membrane estrogen receptor. Using the widely employed approach of tracking recombinant 7TMRs by surface labeling live cells, we have begun to characterize and compare the endocytic fate of GPER to other similarly labeled 7TMRs. Upon ectopic expression in human embryonic kidney HEK-293 cells, functional GPER is generated as these cells acquire the capacity to stimulate cAMP and activate cyclic AMP responsive binding protein in response to estradiol-17 beta stimulation. GPER is detectable on the cell surface by immunofluorescent analysis using HA-specific antibodies, albeit the bulk of the receptor is located intracellularly. Like β1AR (beta 1 adrenergic receptor) and CXCR4 (C-X-C chemokine receptor 4), GPER exits the plasma membrane via clathrin-coated pits and enters early endosomes. Interestingly, GPER has a destination that is uncommon among 7TMRs, as it accumulates in a perinuclear compartment. Like many 7TMRs (approximately one-third), GPER trafficking from the plasma membrane is constitutive (occurs in the absence of agonist). However, its route of intracellular trafficking is highly unusual, as 7TMRs typically recycle to the plasma membrane (e.g. β1AR) or are degraded in lysosomes (e.g. CXCR4). The accumulation of GPER in the perinuclear space and its possible significance for attenuating estrogen action via this newly recognized membrane estrogen receptor is discussed herein. Published by Elsevier Inc.
Blackhall, Fiona H; Merry, Catherine L R; Lyon, Malcolm; Jayson, Gordon C; Folkman, Judah; Javaherian, Kashi; Gallagher, John T
2003-10-01
Endostatin is a naturally occurring proteolytic fragment of the C-terminal domain of collagen XVIII. It inhibits angiogenesis by a mechanism that appears to involve binding to HS (heparan sulphate). We have examined the molecular interaction between endostatin and HS from micro- and macrovessel endothelial cells. Two discrete panels of oligosaccharides were prepared from metabolically radiolabelled HS, using digestion with either heparinase I or III, and then examined for their endostatin affinity using a sensitive filter-binding assay. Two types of endostatin-binding regions were identified: one comprising sulphated domains of five or more disaccharides in length, enriched in 6-O-sulphate groups, and the other contained long heparinase I-resistant fragments. In the latter case, evidence from the present study suggests that the binding region encompasses a sulphated domain fragment and a transition zone of intermediate sulphation. The contribution to binding of specific O-sulphate groups was determined using selectively desulphated HS species, namely HS from Hs2st-/- mutant cells, and by comparing the compositions of endostatin-binding and non-binding oligosaccharides. The results indicate that 6-O-sulphates play a dominant role in site selectivity and 2-O-sulphates are not strictly essential.
Blackhall, Fiona H; Merry, Catherine L R; Lyon, Malcolm; Jayson, Gordon C; Folkman, Judah; Javaherian, Kashi; Gallagher, John T
2003-01-01
Endostatin is a naturally occurring proteolytic fragment of the C-terminal domain of collagen XVIII. It inhibits angiogenesis by a mechanism that appears to involve binding to HS (heparan sulphate). We have examined the molecular interaction between endostatin and HS from micro- and macrovessel endothelial cells. Two discrete panels of oligosaccharides were prepared from metabolically radiolabelled HS, using digestion with either heparinase I or III, and then examined for their endostatin affinity using a sensitive filter-binding assay. Two types of endostatin-binding regions were identified: one comprising sulphated domains of five or more disaccharides in length, enriched in 6-O-sulphate groups, and the other contained long heparinase I-resistant fragments. In the latter case, evidence from the present study suggests that the binding region encompasses a sulphated domain fragment and a transition zone of intermediate sulphation. The contribution to binding of specific O-sulphate groups was determined using selectively desulphated HS species, namely HS from Hs2st-/- mutant cells, and by comparing the compositions of endostatin-binding and non-binding oligosaccharides. The results indicate that 6-O-sulphates play a dominant role in site selectivity and 2-O-sulphates are not strictly essential. PMID:12812520
Heparan sulfate niche for cell proliferation in the adult brain.
Mercier, Frederic; Arikawa-Hirasawa, Eri
2012-02-29
In adulthood, new neurons and glial cells are generated from stem cells in restricted zones of the brain, namely the olfactory bulb (OB), rostral migratory stream (RMS), subventricular zone (SVZ) of the lateral ventricle, sub-callosum zone (SCZ) and sub-granular layer (SGL) of the dentate gyrus. What makes these zones germinal? We previously reported that N-sulfated heparan sulfates (N-sulfated HS) present in specialized extracellular matrix structures (fractones) and vascular basement membranes bind the neurogenic factor FGF-2 (fibroblast growth factor-2) next to stem cells in the anterior SVZ of the lateral ventricle, the most neurogenic zone in adulthood. To determine to which extent cell proliferation is associated with N-sulfated HS, we mapped N-sulfated HS and proliferating cells by immunohistochemistry throughout the adult mouse brain. We found that cell proliferation is associated with N-sulfated HS in the OB, RMS, the whole germinal SVZ, and the SCZ. Cell proliferation was weakly associated with N-sulfated HS in the SGL, but the SGL was directly connected to a sub-cortical N-sulfated HS+ extension of the meninges. The NS-sulfated HS+ structures were blood vessels in the OB, RMS and SCZ, and primarily fractones in the SVZ. N-sulfated HS+ fractones, blood vessels and meninges formed a continuum that coursed along the OB, SVZ, RMS, SCZ and SGL, challenging the view that these structures are independent germinal entities. These results support the possibility that a single anatomical system might be globally responsible for mitogenesis and ultimately the production of new neurons and glial cells in the adult brain. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.
Antiretroviral Activity Of a Novel Pyrimidyl-Di(Diazaspiroalkane) Derivative
Novoselova, E.A.; Riabova, O.B.; Leneva, I.A.; Nesterenko, V.G.; Bolgarin, R.N.; Makarov, V.A.
2017-01-01
A novel compound, 3,3’-(5-nitropyrimidine-4,6-diyl)bis-3,12-diaza-6,9-diazoniadispiro[5.2.5.2]hexadecane tetrachloride dihydrochloride, was synthesized. The compound was found to inhibit the replication of various viral families by blocking specific heparan sulfate receptors on the host cell’s surface. In experiments, the compound was found to be highly effective against several strains of HIV retroviruses. PMID:28461981
Click-coated, heparinized, decellularized vascular grafts
Dimitrievska, Sashka; Cai, Chao; Weyers, Amanda; Balestrini, Jenna L.; Lin, Tylee; Sundaram, Sumati; Hatachi, Go; Spiegel, David A.; Kyriakides, Themis R.; Miao, Jianjun; Li, Guoyun; Niklason, Laura; Linhardt, Robert J.
2014-01-01
A novel method enabling the engineering of a dense and appropriately oriented heparin-containing layer on decellularized aortas has been developed. Amino groups of decellularized aortas were first modified to azido groups using 3-azidobenzoic acid. Azide-clickable dendrons were attached onto the azido groups through “alkyne-azide” click chemistry, affording a ten-fold amplification of adhesions sites. Dendron end groups were finally decorated with end-on modified heparin chains. Heparin chains were oriented like heparan sulfate groups on native endothelial cells surface. XPS, NMR, MS and FTIR were used to characterize the synthesis steps, building the final heparin layered coatings. Continuity of the heparin coating was verified using fluorescent microscopy and histological analysis. Efficacy of heparin linkage was demonstrated with factor Xa antithrombogenic assay and platelet adhesion studies. The results suggest that oriented heparin immobilization to decellularized aortas may improve the in vivo blood compatibility of decellularized aortas and vessels. PMID:25463496
Weyland, M; Griveau, A; Bejaud, J; Benoit, J-P; Coursaget, P; Garcion, E
2013-10-01
Plasmid DNA (pDNA) and small interfering RNAs (siRNAs) are very useful tools for the treatment of cancer. However, pDNA and siRNAs efficacy is restricted by their negative charge and susceptibility to degradation by endonucleases that prevent them penetrating tissue and cellular barriers such as the plasma and endolysosomal membranes. Viral vectors have some advantages but their use is largely limited by their immunogenicity. On the other hand, synthetic nanoparticles have advantage of being relatively non-immunogenic but their ability to deliver nucleic acids remains less efficient than their viral counterparts. The present study is focussed on the development and evaluation of biomimetic lipid nanocapsules (LNCs) functionalized with a L1 papillomavirus type-16 capsid-derived lipopeptide on their surface, for transfection of U87MG glioma cells and Caco-2 colorectal adenocarcinoma cells with pDNA or siRNAs. Since the L1-peptide has been described as a nuclear localization signal able to complex with nucleic acids and bind to heparan sulfate on the cell surface, the structure and function of L1-peptide bound to LNCs (L1-LNCs) were investigated. Although L1-LNCs were shown to complex with both pDNA and siRNAs, the pDNA-L1-LNC complexes showed only weak transfection efficiency. In contrast, siRNA-L1-LNC complexes appeared as effective repressors of targeted messengers. Copyright © 2013 Elsevier B.V. All rights reserved.
Minge, Daniel; Senkov, Oleg; Kaushik, Rahul; Herde, Michel K.; Tikhobrazova, Olga; Wulff, Andreas B.; Mironov, Andrey; van Kuppevelt, Toin H.; Oosterhof, Arie; Kochlamazashvili, Gaga
2017-01-01
Abstract Heparan sulfate (HS) proteoglycans represent a major component of the extracellular matrix and are critical for brain development. However, their function in the mature brain remains to be characterized. Here, acute enzymatic digestion of HS side chains was used to uncover how HSs support hippocampal function in vitro and in vivo. We found that long-term potentiation (LTP) of synaptic transmission at CA3–CA1 Schaffer collateral synapses was impaired after removal of highly sulfated HSs with heparinase 1. This reduction was associated with decreased Ca2+ influx during LTP induction, which was the consequence of a reduced excitability of CA1 pyramidal neurons. At the subcellular level, heparinase treatment resulted in reorganization of the distal axon initial segment, as detected by a reduction in ankyrin G expression. In vivo, digestion of HSs impaired context discrimination in a fear conditioning paradigm and oscillatory network activity in the low theta band after fear conditioning. Thus, HSs maintain neuronal excitability and, as a consequence, support synaptic plasticity and learning. PMID:28119345
The 2.3-Angstrom Structure of Porcine Circovirus 2
DOE Office of Scientific and Technical Information (OSTI.GOV)
Khayat, Reza; Brunn, Nicholas; Speir, Jeffrey A.
Porcine circovirus 2 (PCV2) is a T = 1 nonenveloped icosahedral virus that has had severe impact on the swine industry. Here we report the crystal structure of an N-terminally truncated PCV2 virus-like particle at 2.3-{angstrom} resolution, and the cryo-electron microscopy (cryo-EM) image reconstruction of a full-length PCV2 virus-like particle at 9.6-{angstrom} resolution. This is the first atomic structure of a circovirus. The crystal structure revealed that the capsid protein fold is a canonical viral jelly roll. The loops connecting the strands of the jelly roll define the limited features of the surface. Sulfate ions interacting with the surface andmore » electrostatic potential calculations strongly suggest a heparan sulfate binding site that allows PCV2 to gain entry into the cell. The crystal structure also allowed previously determined epitopes of the capsid to be visualized. The cryo-EM image reconstruction showed that the location of the N terminus, absent in the crystal structure, is inside the capsid. As the N terminus was previously shown to be antigenic, it may externalize through viral 'breathing'.« less
Di Noto, Giuseppe; Bugatti, Antonella; Zendrini, Andrea; Mazzoldi, Elena Laura; Montanelli, Alessandro; Caimi, Luigi; Rusnati, Marco; Ricotta, Doris; Bergese, Paolo
2016-03-15
A novel approach for sorting exosomes from multiple myeloma (MM), monoclonal gammopathy of undetermined significance (MGUS) and healthy individuals is presented. The method is based on the combination of colloidal gold nanoplasmonics and surface plasmon resonance (SPR) biosensing and probes distinctive colloidal properties of MM-derived exosomes, such as molar concentration and cell membrane binding preferences. It allowed to discover that MM patients produce about four folds more exosomes than MGUS and healthy individuals. In addition, it showed that among the analyzed exosomes, only the MM-derived ones bind heparin - a structural analog of heparan sulfate proteoglycans known to mediate exosome endocytosis - with an apparent dissociation constant (Kd) equal to about 1 nM, indicating a high affinity binding. This plasmonic method complements the classical biochemical profiling approach to exosomes, expanding the MM biomarker panel and adding biosensors to the toolbox to diagnose MM. It may find applications for other diseases and has wider interest for fundamental and translational research involving exosomes. Copyright © 2015 Elsevier B.V. All rights reserved.
Metabolic engineering of Chinese hamster ovary cells: Towards a bioengineered heparin
Baik, Jong Youn; Gasimli, Leyla; Yang, Bo; Datta, Payel; Zhang, Fuming; Glass, Charles A.; Esko, Jeffrey D.; Linhardt, Robert J.; Sharfstein, Susan T.
2012-01-01
Heparin is the most widely used pharmaceutical to control blood coagulation in modern medicine. A health crisis that took place in 2008 led to a demand for production of heparin from non-animal sources. Chinese hamster ovary (CHO) cells, commonly used mammalian host cells for production of foreign pharmaceutical proteins in the biopharmaceutical industry, are capable of producing heparan sulfate (HS), a related polysaccharide naturally. Since heparin and HS share the same biosynthetic pathway, we hypothesized that heparin could be produced in CHO cells by metabolic engineering. Based on the expression of endogenous enzymes in the HS / heparin pathways of CHO-S cells, human N-deacetylase/N-sulfotransferase (NDST2) and mouse heparan sulfate 3-O-sulfotransferase 1 (Hs3st1) genes were transfected sequentially into CHO host cells growing in suspension culture. Transfectants were screened using quantitative RT-PCR and Western blotting. Out of 120 clones expressing NDST2 and Hs3st1, 2 clones, Dual-3 and Dual-29, were selected for further analysis. An antithrombin III (ATIII) binding assay using flow cytometry, designed to recognize a key sugar structure characteristic of heparin, indicated that Hs3st1 transfection was capable of increasing ATIII binding. An anti-factor Xa assay, which affords a measure of anticoagulant activity, showed a significant increase in activity in the dual-expressing cell lines. Disaccharide analysis of the engineered HS showed a substantial increase in N-sulfo groups, but did not show a pattern consistent with pharmacological heparin, suggesting that further balancing the expression of transgenes with the expression levels of endogenous enzymes involved in HS / heparin biosynthesis might be necessary. PMID:22326251
Metabolic engineering of Chinese hamster ovary cells: towards a bioengineered heparin.
Baik, Jong Youn; Gasimli, Leyla; Yang, Bo; Datta, Payel; Zhang, Fuming; Glass, Charles A; Esko, Jeffrey D; Linhardt, Robert J; Sharfstein, Susan T
2012-03-01
Heparin is the most widely used pharmaceutical to control blood coagulation in modern medicine. A health crisis that took place in 2008 led to a demand for production of heparin from non-animal sources. Chinese hamster ovary (CHO) cells, commonly used mammalian host cells for production of foreign pharmaceutical proteins in the biopharmaceutical industry, are capable of producing heparan sulfate (HS), a related polysaccharide naturally. Since heparin and HS share the same biosynthetic pathway, we hypothesized that heparin could be produced in CHO cells by metabolic engineering. Based on the expression of endogenous enzymes in the HS/heparin pathways of CHO-S cells, human N-deacetylase/N-sulfotransferase (NDST2) and mouse heparan sulfate 3-O-sulfotransferase 1 (Hs3st1) genes were transfected sequentially into CHO host cells growing in suspension culture. Transfectants were screened using quantitative RT-PCR and Western blotting. Out of 120 clones expressing NDST2 and Hs3st1, 2 clones, Dual-3 and Dual-29, were selected for further analysis. An antithrombin III (ATIII) binding assay using flow cytometry, designed to recognize a key sugar structure characteristic of heparin, indicated that Hs3st1 transfection was capable of increasing ATIII binding. An anti-factor Xa assay, which affords a measure of anticoagulant activity, showed a significant increase in activity in the dual-expressing cell lines. Disaccharide analysis of the engineered HS showed a substantial increase in N-sulfo groups, but did not show a pattern consistent with pharmacological heparin, suggesting that further balancing the expression of transgenes with the expression levels of endogenous enzymes involved in HS/heparin biosynthesis might be necessary. Copyright © 2012 Elsevier Inc. All rights reserved.
Human Mucosal Mast Cells Capture HIV-1 and Mediate Viral trans-Infection of CD4+ T Cells.
Jiang, Ai-Ping; Jiang, Jin-Feng; Wei, Ji-Fu; Guo, Ming-Gao; Qin, Yan; Guo, Qian-Qian; Ma, Li; Liu, Bao-Chi; Wang, Xiaolei; Veazey, Ronald S; Ding, Yong-Bing; Wang, Jian-Hua
2015-12-30
The gastrointestinal mucosa is the primary site where human immunodeficiency virus type 1 (HIV-1) invades, amplifies, and becomes persistently established, and cell-to-cell transmission of HIV-1 plays a pivotal role in mucosal viral dissemination. Mast cells are widely distributed in the gastrointestinal tract and are early targets for invasive pathogens, and they have been shown to have increased density in the genital mucosa in HIV-infected women. Intestinal mast cells express numerous pathogen-associated molecular patterns (PAMPs) and have been shown to combat various viral, parasitic, and bacterial infections. However, the role of mast cells in HIV-1 infection is poorly defined. In this study, we investigated their potential contributions to HIV-1 transmission. Mast cells isolated from gut mucosal tissues were found to express a variety of HIV-1 attachment factors (HAFs), such as DC-SIGN, heparan sulfate proteoglycan (HSPG), and α4β7 integrin, which mediate capture of HIV-1 on the cell surface. Intriguingly, following coculture with CD4(+) T cells, mast cell surface-bound viruses were efficiently transferred to target T cells. Prior blocking with anti-HAF antibody or mannan before coculture impaired viral trans-infection. Cell-cell conjunctions formed between mast cells and T cells, to which viral particles were recruited, and these were required for efficient cell-to-cell HIV-1 transmission. Our results reveal a potential function of gut mucosal mast cells in HIV-1 dissemination in tissues. Strategies aimed at preventing viral capture and transfer mediated by mast cells could be beneficial in combating primary HIV-1 infection. In this study, we demonstrate the role of human mast cells isolated from mucosal tissues in mediating HIV-1 trans-infection of CD4(+) T cells. This finding facilitates our understanding of HIV-1 mucosal infection and will benefit the development of strategies to combat primary HIV-1 dissemination. Copyright © 2016, American Society for Microbiology. All Rights Reserved.
Harthan, Laura B; McFarland, Douglas C; Velleman, Sandra G
2014-01-01
Posthatch satellite cell mitotic activity is a critical component of muscle development and growth. Satellite cells are myogenic stem cells that can be induced by nutrition to follow other cellular developmental pathways, and whose mitotic activity declines with age. The objective of the current study was to determine the effect of restricting protein synthesis on the proliferation and differentiation, expression of myogenic transcriptional regulatory factors myogenic determination factor 1, myogenin, and myogenic regulatory factor 4, and expression of the heparan sulfate proteoglycans syndecan-4 and glypican-1 in satellite cells isolated from 1-d-, 7-wk-, and 16-wk-old turkey pectoralis major muscle (1 d, 7 wk, and 16 wk cells, respectively) by using variable concentrations of Met and Cys. Four Met concentrations-30 (control), 7.5, 3, or 0 mg/L with 3.2 mg/L of Cys per 1 mg/L of Met-were used for culture of satellite cells to determine the effect of nutrition and age on satellite cell behavior during proliferation and differentiation. Proliferation was reduced by lower Met and Cys concentrations in all ages at 96 h of proliferation. Differentiation was increased in the 1 d Met-restricted cells, whereas the 7 wk cells treated with 3 mg/L of Met had decreased differentiation. Reduced Met and Cys levels from the control did not significantly affect the 16 wk cells at 72 h of differentiation. However, medium with no Met or Cys suppressed differentiation at all ages. The expression of myogenic determination factor 1, myogenin, myogenic regulatory factor 4, syndecan-4, and glypican-1 was differentially affected by age and Met or Cys treatment. These data demonstrate the age-specific manner in which turkey pectoralis major muscle satellite cells respond to nutritional availability and the importance of defining optimal nutrition to maximize satellite cell proliferation and differentiation for subsequent muscle mass accretion.
Miyazaki, Tatsuya; Miyauchi, Satoshi; Anada, Takahisa; Tawada, Akira; Suzuki, Osamu
2015-10-01
Integrins and their ligands have been suggested to be associated with osteoclast-mediated bone resorption. The present study was designed to investigate whether chondroitin sulfate E (CS-E), which is one of the sulfated glycosaminoglycans (GAGs), is involved in osteoactivin (OA) activity, and osteoclast differentiation. The binding affinity of sulfated GAGs to integrin and its ligand was measured using biotin-labeled CS-E, and the osteoclast differentiation was evaluated by tartrate-resistant acid phosphatase staining and a pit formation assay. CS-E as well as CS-B, synthetic chondroitin polysulfate, and heparin inhibited osteoclast differentiation of bone marrow-derived macrophages. Pre-coating of OA to synthetic calcium phosphate-coated plates enhanced the osteoclastic differentiation of RAW264 cells, and addition of a neutralizing antibody to OA inhibited its differentiation. CS-E bound not only to OA, fibronectin, and vitronectin, but also to its receptor integrin αVβ3, and inhibited the direct binding of OA to integrin αVβ3. Furthermore, CS-E blocked the binding of OA to cells and inhibited OA-induced osteoclastic differentiation. On the other hand, heparinase treatment of RAW264 cells inhibited osteoclastic differentiation. Since binding of OA to the cells was inhibited by the presence of heparan sulfate or heparinase treatment of cells, heparan sulfate proteoglycan (HSPG) was also considered to be an OA receptor. Taken together, the present results suggest that CS-E is capable of inhibiting OA-induced osteoclast differentiation by blocking the interaction of OA to integrin αVβ3 and HSPG. © 2015 Wiley Periodicals, Inc.
Mundy, Christina; Yasuda, Tadashi; Kinumatsu, Takashi; Yamaguchi, Yu; Iwamoto, Masahiro; Enomoto-Iwamoto, Motomi; Koyama, Eiki; Pacifici, Maurizio
2011-03-01
Heparan sulfate proteoglycans (HSPGs) regulate a number of major developmental processes, but their roles in synovial joint formation remain unknown. Here we created conditional mouse embryo mutants lacking Ext1 in developing joints by mating Ext1(f/f) and Gdf5-Cre mice. Ext1 encodes a subunit of the Ext1/Ext2 Golgi-associated protein complex responsible for heparan sulfate (HS) synthesis. The proximal limb joints did form in the Gdf5-Cre;Ext1(f/f) mutants, but contained an uneven articulating superficial zone that expressed very low lubricin levels. The underlying cartilaginous epiphysis was deranged as well and displayed random patterns of cell proliferation and matrillin-1 and collagen IIA expression, indicative of an aberrant phenotypic definition of the epiphysis itself. Digit joints were even more affected, lacked a distinct mesenchymal interzone and were often fused likely as a result of local abnormal BMP and hedgehog activity and signaling. Interestingly, overall growth and lengthening of long bones were also delayed in the mutants. To test whether Ext1 function is needed for joint formation at other sites, we examined the spine. Indeed, entire intervertebral discs, normally composed by nucleus pulposus surrounded by the annulus fibrosus, were often missing in Gdf5-Cre;Ext1(f/f) mice. When disc remnants were present, they displayed aberrant organization and defective joint marker expression. Similar intervertebral joint defects and fusions occurred in Col2-Cre;β-catenin(f/f) mutants. The study provides novel evidence that local Ext1 expression and HS production are needed to maintain the phenotype and function of joint-forming cells and coordinate local signaling by BMP, hedgehog and Wnt/β-catenin pathways. The data indicate also that defects in joint formation reverberate on, and delay, overall long bone growth. Copyright © 2011 Elsevier Inc. All rights reserved.
Shaik, Sadiq S; Soltau, Thomas D; Chaturvedi, Gaurav; Totapally, Balagangadhar; Hagood, James S; Andrews, William W; Athar, Mohammad; Voitenok, Nikolai N; Killingsworth, Cheryl R; Patel, Rakesh P; Fallon, Michael B; Maheshwari, Akhil
2009-02-27
CXC chemokines with a glutamate-leucine-arginine (ELR) tripeptide motif (ELR(+) CXC chemokines) play an important role in leukocyte trafficking into the tissues. For reasons that are not well elucidated, circulating leukocytes are recruited into the tissues mainly in small vessels such as capillaries and venules. Because ELR(+) CXC chemokines are important mediators of endothelial-leukocyte interaction, we compared chemokine expression by microvascular and aortic endothelium to investigate whether differences in chemokine expression by various endothelial types could, at least partially, explain the microvascular localization of endothelial-leukocyte interaction. Both in vitro and in vivo models indicate that ELR(+) CXC chemokine expression is higher in microvascular endothelium than in aortic endothelial cells. These differences can be explained on the basis of the preferential activation of endothelial chemokine production by low intensity shear stress. Low shear activated endothelial ELR(+) CXC chemokine production via cell surface heparan sulfates, beta(3)-integrins, focal adhesion kinase, the mitogen-activated protein kinase p38beta, mitogen- and stress-associated protein kinase-1, and the transcription factor.
Sulfated Hexasaccharides Attenuate Metastasis by Inhibition of P-selectin and Heparanase1
Borsig, Lubor; Vlodavsky, Israel; Ishai-Michaeli, Rivka; Torri, Giangiacomo; Vismara, Elena
2011-01-01
Development of compounds that target both heparanase and selectins is emerging as a promising approach for cancer therapy. Selectins are vascular cell adhesion molecules that mediate tumor cell interactions with platelets, leukocytes, and the vascular endothelium. Heparanase is an endoglycosidase that degrades heparan sulfate in the tumor microenvironment, cell surfaces, and vessel wall. Acting together, these molecules facilitate tumor cell arrest, extravasation, and metastasis. Here, we report the preparation of novel semisynthetic sulfated tri mannose C-C-linked dimers (STMCs) endowed with heparanase and selectin inhibitory activity. The P-selectin specificity of the STMC was defined by the anomeric linkage of the C-C bond. This STMC hexasaccharide is an effective inhibitor of P-selectin in vivo. We show that selective inhibition of heparanase attenuates metastasis in B16-BL6 melanoma cells, expressing high levels of this endoglycosidase, but has no effect on the metastasis of MC-38 carcinoma cells that express little or no heparanase activity. P-selectin-specific STMC attenuated metastasis in both animal models, indicating that inhibition of tumor cell interaction with the vascular endothelium is critical for cancer dissemination. Thus, the small size, the stability of the C-C bond, and the chemically defined structure of the newly generated STMCs make them superior to heparin derivatives and signify STMCs as valuable candidates for further evaluation. PMID:21532885
Xiong, Anqi; Kundu, Soumi; Forsberg, Maud; Xiong, Yuyuan; Bergström, Tobias; Paavilainen, Tanja; Kjellén, Lena; Li, Jin-Ping; Forsberg-Nilsson, Karin
2017-10-01
Heparan sulfate proteoglycans (HSPGs), ubiquitous components of mammalian cells, play important roles in development and homeostasis. These molecules are located primarily on the cell surface and in the pericellular matrix, where they interact with a multitude of macromolecules, including many growth factors. Manipulation of the enzymes involved in biosynthesis and modification of HSPG structures alters the properties of stem cells. Here, we focus on the involvement of heparanase (HPSE), the sole endo-glucuronidase capable of cleaving of HS, in differentiation of embryonic stem cells into the cells of the neural lineage. Embryonic stem (ES) cells overexpressing HPSE (Hpse-Tg) proliferated more rapidly than WT ES cells in culture and formed larger teratomas in vivo. In addition, differentiating Hpse-Tg ES cells also had a higher growth rate, and overexpression of HPSE in NSPCs enhanced Erk and Akt phosphorylation. Employing a two-step, monolayer differentiation, we observed an increase in HPSE as wild-type (WT) ES cells differentiated into neural stem and progenitor cells followed by down-regulation of HPSE as these NSPCs differentiated into mature cells of the neural lineage. Furthermore, NSPCs overexpressing HPSE gave rise to more oligodendrocytes than WT cultures, with a concomitant reduction in the number of neurons. Our present findings emphasize the importance of HS, in neural differentiation and suggest that by regulating the availability of growth factors and, or other macromolecules, HPSE promotes differentiation into oligodendrocytes. Copyright © 2016 Elsevier B.V. All rights reserved.
Thompson, Sophie M; Connell, Marilyn G; van Kuppevelt, Toin H; Xu, Ruoyan; Turnbull, Jeremy E; Losty, Paul D; Fernig, David G; Jesudason, Edwin C
2011-06-14
Heparan sulfate (HS) is present on the surface of virtually all mammalian cells and is a major component of the extracellular matrix (ECM), where it plays a pivotal role in cell-cell and cell-matrix cross-talk through its large interactome. Disruption of HS biosynthesis in mice results in neonatal death as a consequence of malformed lungs, indicating that HS is crucial for airway morphogenesis. Neonatal mortality (~50%) in newborns with congenital diaphragmatic hernia (CDH) is principally associated with lung hypoplasia and pulmonary hypertension. Given the importance of HS for lung morphogenesis, we investigated developmental changes in HS structure in normal and hypoplastic lungs using the nitrofen rat model of CDH and semi-synthetic bacteriophage ('phage) display antibodies, which identify distinct HS structures. The pulmonary pattern of elaborated HS structures is developmentally regulated. For example, the HS4E4V epitope is highly expressed in sub-epithelial mesenchyme of E15.5 - E17.5 lungs and at a lower level in more distal mesenchyme. However, by E19.5, this epitope is expressed similarly throughout the lung mesenchyme.We also reveal abnormalities in HS fine structure and spatiotemporal distribution of HS epitopes in hypoplastic CDH lungs. These changes involve structures recognised by key growth factors, FGF2 and FGF9. For example, the EV3C3V epitope, which was abnormally distributed in the mesenchyme of hypoplastic lungs, is recognised by FGF2. The observed spatiotemporal changes in HS structure during normal lung development will likely reflect altered activities of many HS-binding proteins regulating lung morphogenesis. Abnormalities in HS structure and distribution in hypoplastic lungs can be expected to perturb HS:protein interactions, ECM microenvironments and crucial epithelial-mesenchyme communication, which may contribute to lung dysmorphogenesis. Indeed, a number of epitopes correlate with structures recognised by FGFs, suggesting a functional consequence of the observed changes in HS in these lungs. These results identify a novel, significant molecular defect in hypoplastic lungs and reveals HS as a potential contributor to hypoplastic lung development in CDH. Finally, these results afford the prospect that HS-mimetic therapeutics could repair defective signalling in hypoplastic lungs, improve lung growth, and reduce CDH mortality.
2011-01-01
Background Heparan sulfate (HS) is present on the surface of virtually all mammalian cells and is a major component of the extracellular matrix (ECM), where it plays a pivotal role in cell-cell and cell-matrix cross-talk through its large interactome. Disruption of HS biosynthesis in mice results in neonatal death as a consequence of malformed lungs, indicating that HS is crucial for airway morphogenesis. Neonatal mortality (~50%) in newborns with congenital diaphragmatic hernia (CDH) is principally associated with lung hypoplasia and pulmonary hypertension. Given the importance of HS for lung morphogenesis, we investigated developmental changes in HS structure in normal and hypoplastic lungs using the nitrofen rat model of CDH and semi-synthetic bacteriophage ('phage) display antibodies, which identify distinct HS structures. Results The pulmonary pattern of elaborated HS structures is developmentally regulated. For example, the HS4E4V epitope is highly expressed in sub-epithelial mesenchyme of E15.5 - E17.5 lungs and at a lower level in more distal mesenchyme. However, by E19.5, this epitope is expressed similarly throughout the lung mesenchyme. We also reveal abnormalities in HS fine structure and spatiotemporal distribution of HS epitopes in hypoplastic CDH lungs. These changes involve structures recognised by key growth factors, FGF2 and FGF9. For example, the EV3C3V epitope, which was abnormally distributed in the mesenchyme of hypoplastic lungs, is recognised by FGF2. Conclusions The observed spatiotemporal changes in HS structure during normal lung development will likely reflect altered activities of many HS-binding proteins regulating lung morphogenesis. Abnormalities in HS structure and distribution in hypoplastic lungs can be expected to perturb HS:protein interactions, ECM microenvironments and crucial epithelial-mesenchyme communication, which may contribute to lung dysmorphogenesis. Indeed, a number of epitopes correlate with structures recognised by FGFs, suggesting a functional consequence of the observed changes in HS in these lungs. These results identify a novel, significant molecular defect in hypoplastic lungs and reveals HS as a potential contributor to hypoplastic lung development in CDH. Finally, these results afford the prospect that HS-mimetic therapeutics could repair defective signalling in hypoplastic lungs, improve lung growth, and reduce CDH mortality. PMID:21672206
Sterner, Eric; Masuko, Sayaka; Li, Guoyun; Li, Lingyun; Green, Dixy E.; Otto, Nigel J.; Xu, Yongmei; DeAngelis, Paul L.; Liu, Jian; Dordick, Jonathan S.; Linhardt, Robert J.
2014-01-01
Four well-defined heparan sulfate (HS) block copolymers containing S-domains (high sulfo group content) placed adjacent to N-domains (low sulfo group content) were chemoenzymatically synthesized and characterized. The domain lengths in these HS block co-polymers were ∼40 saccharide units. Microtiter 96-well and three-dimensional cell-based microarray assays utilizing murine immortalized bone marrow (BaF3) cells were developed to evaluate the activity of these HS block co-polymers. Each recombinant BaF3 cell line expresses only a single type of fibroblast growth factor receptor (FGFR) but produces neither HS nor fibroblast growth factors (FGFs). In the presence of different FGFs, BaF3 cell proliferation showed clear differences for the four HS block co-polymers examined. These data were used to examine the two proposed signaling models, the symmetric FGF2-HS2-FGFR2 ternary complex model and the asymmetric FGF2-HS1-FGFR2 ternary complex model. In the symmetric FGF2-HS2-FGFR2 model, two acidic HS chains bind in a basic canyon located on the top face of the FGF2-FGFR2 protein complex. In this model the S-domains at the non-reducing ends of the two HS proteoglycan chains are proposed to interact with the FGF2-FGFR2 protein complex. In contrast, in the asymmetric FGF2-HS1-FGFR2 model, a single HS chain interacts with the FGF2-FGFR2 protein complex through a single S-domain that can be located at any position within an HS chain. Our data comparing a series of synthetically prepared HS block copolymers support a preference for the symmetric FGF2-HS2-FGFR2 ternary complex model. PMID:24563485
Okolicsanyi, Rachel K; Oikari, Lotta E; Yu, Chieh; Griffiths, Lyn R; Haupt, Larisa M
2018-01-01
Background: Due to their relative ease of isolation and their high ex vivo and in vitro expansive potential, human mesenchymal stem cells (hMSCs) are an attractive candidate for therapeutic applications in the treatment of brain injury and neurological diseases. Heparan sulfate proteoglycans (HSPGs) are a family of ubiquitous proteins involved in a number of vital cellular processes including proliferation and stem cell lineage differentiation. Methods: Following the determination that hMSCs maintain neural potential throughout extended in vitro expansion, we examined the role of HSPGs in mediating the neural potential of hMSCs. hMSCs cultured in basal conditions (undifferentiated monolayer cultures) were found to co-express neural markers and HSPGs throughout expansion with modulation of the in vitro niche through the addition of exogenous HS influencing cellular HSPG and neural marker expression. Results: Conversion of hMSCs into hMSC Induced Neurospheres (hMSC IN) identified distinctly localized HSPG staining within the spheres along with altered gene expression of HSPG core protein and biosynthetic enzymes when compared to undifferentiated hMSCs. Conclusion: Comparison of markers of pluripotency, neural self-renewal and neural lineage specification between hMSC IN, hMSC and human neural stem cell (hNSC H9) cultures suggest that in vitro generated hMSC IN may represent an intermediary neurogenic cell type, similar to a common neural progenitor cell. In addition, this data demonstrates HSPGs and their biosynthesis machinery, are associated with hMSC IN formation. The identification of specific HSPGs driving hMSC lineage-specification will likely provide new markers to allow better use of hMSCs in therapeutic applications and improve our understanding of human neurogenesis.
A Novel Approach for Preventing HIV Infection and Reducing Risk to U.S. Military Personnel
2012-09-01
polymers suchaschondroitin sulfate , inhibit the ability of semen to enhance HIV infection. Oversulfation of chondroitin sulfate converted this polymer...Deficient in Enhancing HIV Infection We previously demonstrated that the anionic polymers heparin and dextran sulfate , but not less negatively charged...2009). Spermatozoa capture HIV-1 through heparan sulfate and efficiently transmit the virus to dendritic cells. J. Exp. Med. 206, 2717– 2733. de
Sanderson, Patience; Stickney, Morgan; Leach, Franklin E; Xia, Qiangwei; Yu, Yanlei; Zhang, Fuming; Linhardt, Robert J; Amster, I Jonathan
2018-04-13
Reverse polarity capillary zone electrophoresis coupled to negative ion mode mass spectrometry (CZE-MS) is shown to be an effective and sensitive tool for the analysis of glycosaminoglycan mixtures. Covalent modification of the inner wall of the separation capillary with neutral or cationic reagents produces a stable and durable surface that provides reproducible separations. By combining CZE-MS with a cation-coated capillary and a sheath flow interface, a rapid and reliable method has been developed for the analysis of sulfated oligosaccharides from dp4 to dp12. Several different mixtures have been separated and detected by mass spectrometry. The mixtures were selected to test the capability of this approach to resolve subtle differences in structure, such as sulfation position and epimeric variation of the uronic acid. The system was applied to a complex mixture of heparin/heparan sulfate oligosaccharides varying in chain length from dp3 to dp12 and more than 80 molecular compositions were identified by accurate mass measurement. Copyright © 2018 Elsevier B.V. All rights reserved.
Normal levels of anticoagulant heparan sulfate are not essential for normal hemostasis
HajMohammadi, Sassan; Enjyoji, Keiichi; Princivalle, Marc; Christi, Patricia; Lech, Miroslav; Beeler, David; Rayburn, Helen; Schwartz, John J.; Barzegar, Samad; de Agostini, Ariane I.; Post, Mark J.; Rosenberg, Robert D.; Shworak, Nicholas W.
2003-01-01
Endothelial cell production of anticoagulant heparan sulfate (HSact) is controlled by the Hs3st1 gene, which encodes the rate-limiting enzyme heparan sulfate 3-O-sulfotransferase-1 (3-OST-1). In vitro, HSact dramatically enhances the neutralization of coagulation proteases by antithrombin. The in vivo role of HSact was evaluated by generating Hs3st1–/– knockout mice. Hs3st1–/– animals were devoid of 3-OST-1 enzyme activity in plasma and tissue extracts. Nulls showed dramatic reductions in tissue levels of HSact but maintained wild-type levels of tissue fibrin accumulation under both normoxic and hypoxic conditions. Given that vascular HSact predominantly occurs in the subendothelial matrix, mice were subjected to a carotid artery injury assay in which ferric chloride administration induces de-endothelialization and occlusive thrombosis. Hs3st1–/– and Hs3st1+/+ mice yielded indistinguishable occlusion times and comparable levels of thrombin•antithrombin complexes. Thus, Hs3st1–/– mice did not show an obvious procoagulant phenotype. Instead, Hs3st1–/– mice exhibited genetic background–specific lethality and intrauterine growth retardation, without evidence of a gross coagulopathy. Our results demonstrate that the 3-OST-1 enzyme produces the majority of tissue HSact. Surprisingly, this bulk of HSact is not essential for normal hemostasis in mice. Instead, 3-OST-1–deficient mice exhibited unanticipated phenotypes suggesting that HSact or additional 3-OST-1–derived structures may serve alternate biologic roles. PMID:12671048
Cluff, Mark; Kingston, Joseph; Hill, Denzil; Chen, Haiyan; Hoehne, Soeren; Malleske, Daniel T.; Kaur, Rajwinederjit
2012-01-01
Lung endothelial cells respond to changes in vascular pressure through mechanotransduction pathways that alter barrier function via non-Starling mechanism(s). Components of the endothelial glycocalyx have been shown to participate in mechanotransduction in vitro and in systemic vessels, but the glycocalyx's role in mechanosensing and pulmonary barrier function has not been characterized. Mechanotransduction pathways may represent novel targets for therapeutic intervention during states of elevated pulmonary pressure such as acute heart failure, fluid overload, and mechanical ventilation. Our objective was to assess the effects of increasing vascular pressure on whole lung filtration coefficient (Kfc) and characterize the role of endothelial heparan sulfates in mediating mechanotransduction and associated increases in Kfc. Isolated perfused rat lung preparation was used to measure Kfc in response to changes in vascular pressure in combination with superimposed changes in airway pressure. The roles of heparan sulfates, nitric oxide, and reactive oxygen species were investigated. Increases in capillary pressure altered Kfc in a nonlinear relationship, suggesting non-Starling mechanism(s). nitro-l-arginine methyl ester and heparanase III attenuated the effects of increased capillary pressure on Kfc, demonstrating active mechanotransduction leading to barrier dysfunction. The nitric oxide (NO) donor S-nitrosoglutathione exacerbated pressure-mediated increase in Kfc. Ventilation strategies altered lung NO concentration and the Kfc response to increases in vascular pressure. This is the first study to demonstrate a role for the glycocalyx in whole lung mechanotransduction and has important implications in understanding the regulation of vascular permeability in the context of vascular pressure, fluid status, and ventilation strategies. PMID:22160307
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gladwin, A.J.; Dixon, J.; Loftus, S.K.
Heparan sulfate-N-deacetylase/N-sulfotransferase (HSST) catalyzes both the N-deacetylation and the N-sulfation of heparan sulfate. Previous studies have resulted in the isolation of the human HSST gene from within the Treacher Collins syndrome locus (TCOF1) critical region on 5q. In the present study, the genomic organization of the HSST gene has been elucidated, and the 14 exons identified have been tested for TCOF1-specific mutations. As a result of these studies, mutations within the coding sequence and adjacent splice junctions of HSST can be excluded from a causative role in the pathogenesis of Treacher Collins syndrome. 13 refs., 1 fig., 2 tabs.
Fatoux-Ardore, Marie; Peysselon, Franck; Weiss, Anthony; Bastien, Patrick; Pratlong, Francine; Ricard-Blum, Sylvie
2014-02-01
We have set up an assay to study the interactions of live pathogens with their hosts by using protein and glycosaminoglycan arrays probed by surface plasmon resonance imaging. We have used this assay to characterize the interactions of Leishmania promastigotes with ~70 mammalian host biomolecules (extracellular proteins, glycosaminoglycans, growth factors, cell surface receptors). We have identified, in total, 27 new partners (23 proteins, 4 glycosaminoglycans) of procyclic promastigotes of six Leishmania species and 18 partners (15 proteins, 3 glycosaminoglycans) of three species of stationary-phase promastigotes for all the strains tested. The diversity of the interaction repertoires of Leishmania parasites reflects their dynamic and complex interplay with their mammalian hosts, which depends mostly on the species and strains of Leishmania. Stationary-phase Leishmania parasites target extracellular matrix proteins and glycosaminoglycans, which are highly connected in the extracellular interaction network. Heparin and heparan sulfate bind to most Leishmania strains tested, and 6-O-sulfate groups play a crucial role in these interactions. Numerous Leishmania strains bind to tropoelastin, and some strains are even able to degrade it. Several strains interact with collagen VI, which is expressed by macrophages. Most Leishmania promastigotes interact with several regulators of angiogenesis, including antiangiogenic factors (endostatin, anastellin) and proangiogenic factors (ECM-1, VEGF, and TEM8 [also known as anthrax toxin receptor 1]), which are regulated by hypoxia. Since hypoxia modulates the infection of macrophages by the parasites, these interactions might influence the infection of host cells by Leishmania.
Fatoux-Ardore, Marie; Peysselon, Franck; Weiss, Anthony; Bastien, Patrick; Pratlong, Francine
2014-01-01
We have set up an assay to study the interactions of live pathogens with their hosts by using protein and glycosaminoglycan arrays probed by surface plasmon resonance imaging. We have used this assay to characterize the interactions of Leishmania promastigotes with ∼70 mammalian host biomolecules (extracellular proteins, glycosaminoglycans, growth factors, cell surface receptors). We have identified, in total, 27 new partners (23 proteins, 4 glycosaminoglycans) of procyclic promastigotes of six Leishmania species and 18 partners (15 proteins, 3 glycosaminoglycans) of three species of stationary-phase promastigotes for all the strains tested. The diversity of the interaction repertoires of Leishmania parasites reflects their dynamic and complex interplay with their mammalian hosts, which depends mostly on the species and strains of Leishmania. Stationary-phase Leishmania parasites target extracellular matrix proteins and glycosaminoglycans, which are highly connected in the extracellular interaction network. Heparin and heparan sulfate bind to most Leishmania strains tested, and 6-O-sulfate groups play a crucial role in these interactions. Numerous Leishmania strains bind to tropoelastin, and some strains are even able to degrade it. Several strains interact with collagen VI, which is expressed by macrophages. Most Leishmania promastigotes interact with several regulators of angiogenesis, including antiangiogenic factors (endostatin, anastellin) and proangiogenic factors (ECM-1, VEGF, and TEM8 [also known as anthrax toxin receptor 1]), which are regulated by hypoxia. Since hypoxia modulates the infection of macrophages by the parasites, these interactions might influence the infection of host cells by Leishmania. PMID:24478075
Role of the endothelial surface layer in neutrophil recruitment.
Marki, Alex; Esko, Jeffrey D; Pries, Axel R; Ley, Klaus
2015-10-01
Neutrophil recruitment in most tissues is limited to postcapillary venules, where E- and P-selectins are inducibly expressed by venular endothelial cells. These molecules support neutrophil rolling via binding of PSGL-1 and other ligands on neutrophils. Selectins extend ≤ 38 nm above the endothelial plasma membrane, and PSGL-1 extends to 50 nm above the neutrophil plasma membrane. However, endothelial cells are covered with an ESL composed of glycosaminoglycans that is ≥ 500 nm thick and has measurable resistance against compression. The neutrophil surface is also covered with a surface layer. These surface layers would be expected to completely shield adhesion molecules; thus, neutrophils should not be able to roll and adhere. However, in the cremaster muscle and in many other models investigated using intravital microscopy, neutrophils clearly roll, and their rolling is easily and quickly induced. This conundrum was thought to be resolved by the observation that the induction of selectins is accompanied by ESL shedding; however, ESL shedding only partially reduces the ESL thickness (to 200 nm) and thus is insufficient to expose adhesion molecules. In addition to its antiadhesive functions, the ESL also presents neutrophil arrest-inducing chemokines. ESL heparan sulfate can also bind L-selectin expressed by the neutrophils, which contributes to rolling and arrest. We conclude that ESL has both proadhesive and antiadhesive functions. However, most previous studies considered either only the proadhesive or only the antiadhesive effects of the ESL. An integrated model for the role of the ESL in neutrophil rolling, arrest, and transmigration is needed. © Society for Leukocyte Biology.
Role of the endothelial surface layer in neutrophil recruitment
Marki, Alex; Esko, Jeffrey D.; Pries, Axel R.; Ley, Klaus
2015-01-01
Neutrophil recruitment in most tissues is limited to postcapillary venules, where E- and P-selectins are inducibly expressed by venular endothelial cells. These molecules support neutrophil rolling via binding of PSGL-1 and other ligands on neutrophils. Selectins extend ≤38 nm above the endothelial plasma membrane, and PSGL-1 extends to 50 nm above the neutrophil plasma membrane. However, endothelial cells are covered with an ESL composed of glycosaminoglycans that is ≥500 nm thick and has measurable resistance against compression. The neutrophil surface is also covered with a surface layer. These surface layers would be expected to completely shield adhesion molecules; thus, neutrophils should not be able to roll and adhere. However, in the cremaster muscle and in many other models investigated using intravital microscopy, neutrophils clearly roll, and their rolling is easily and quickly induced. This conundrum was thought to be resolved by the observation that the induction of selectins is accompanied by ESL shedding; however, ESL shedding only partially reduces the ESL thickness (to 200 nm) and thus is insufficient to expose adhesion molecules. In addition to its antiadhesive functions, the ESL also presents neutrophil arrest-inducing chemokines. ESL heparan sulfate can also bind L-selectin expressed by the neutrophils, which contributes to rolling and arrest. We conclude that ESL has both proadhesive and antiadhesive functions. However, most previous studies considered either only the proadhesive or only the antiadhesive effects of the ESL. An integrated model for the role of the ESL in neutrophil rolling, arrest, and transmigration is needed. PMID:25979432
Targeting of adhesion molecules as a therapeutic strategy in multiple myeloma.
Neri, Paola; Bahlis, Nizar J
2012-09-01
Multiple myeloma (MM) is a clonal disorder of plasma cells that remains, for the most part, incurable despite the advent of several novel therapeutic agents. Tumor cells in this disease are cradled within the bone marrow (BM) microenvironment by an array of adhesive interactions between the BM cellular residents, the surrounding extracellular matrix (ECM) components such as fibronectin (FN), laminin, vascular cell adhesion molecule-1 (VCAM-1), proteoglycans, collagens and hyaluronan, and a variety of adhesion molecules on the surface of MM cells including integrins, hyaluronan receptors (CD44 and RHAMM) and heparan sulfate proteoglycans. Several signaling responses are activated by these interactions, affecting the survival, proliferation and migration of MM cells. An important consequence of these direct adhesive interactions between the BM/ECM and MM cells is the development of drug resistance. This phenomenon is termed "cell adhesion-mediated drug resistance" (CAM-DR) and it is thought to be one of the major mechanisms by which MM cells escape the cytotoxic effects of therapeutic agents. This review will focus on the adhesion molecules involved in the cross-talk between MM cells and components of the BM microenvironment. The complex signaling networks downstream of these adhesive molecules mediated by direct ligand binding or inside-out soluble factors signaling will also be reviewed. Finally, novel therapeutic strategies targeting these molecules will be discussed. Identification of the mediators of MM-BM interaction is essential to understand MM biology and to elucidate novel therapeutic targets for this disease.
The dependence of chemokine–glycosaminoglycan interactions on chemokine oligomerization
Dyer, Douglas P; Salanga, Catherina L; Volkman, Brian F; Kawamura, Tetsuya; Handel, Tracy M
2016-01-01
Both chemokine oligomerization and binding to glycosaminoglycans (GAGs) are required for their function in cell recruitment. Interactions with GAGs facilitate the formation of chemokine gradients, which provide directional cues for migrating cells. In contrast, chemokine oligomerization is thought to contribute to the affinity of GAG interactions by providing a more extensive binding surface than single subunits alone. However, the importance of chemokine oligomerization to GAG binding has not been extensively quantified. Additionally, the ability of chemokines to form different oligomers has been suggested to impart specificity to GAG interactions, but most studies have been limited to heparin. In this study, several differentially oligomerizing chemokines (CCL2, CCL3, CCL5, CCL7, CXCL4, CXCL8, CXCL11 and CXCL12) and select oligomerization-deficient mutants were systematically characterized by surface plasmon resonance to determine their relative affinities for heparin, heparan sulfate (HS) and chondroitin sulfate-A (CS-A). Wild-type chemokines demonstrated a hierarchy of binding affinities for heparin and HS that was markedly dependent on oligomerization. These results were corroborated by their relative propensity to accumulate on cells and the critical role of oligomerization in cell presentation. CS-A was found to exhibit greater chemokine selectivity than heparin or HS, as it only bound a subset of chemokines; moreover, binding to CS-A was ablated with oligomerization-deficient mutants. Overall, this study definitively demonstrates the importance of oligomerization for chemokine–GAG interactions, and demonstrates diversity in the affinity and specificity of different chemokines for GAGs. These data support the idea that GAG interactions provide a mechanism for fine-tuning chemokine function. PMID:26582609
Hwang, Jung-Ah; Kim, Yujin; Hong, Seung-Hyun; Lee, Jieun; Cho, Yong Gu; Han, Ji-Youn; Kim, Young-Ho; Han, Joungho; Shim, Young Mog; Lee, Yeon-Su; Kim, Duk-Hwan
2013-01-01
Background This study was aimed at investigating the functional significance of heparan sulfate (glucosamine) 3-O-sulfotransferase 2 (HS3ST2) hypermethylation in non-small cell lung cancer (NSCLC). Methodology/ Principal Findings HS3ST2 hypermethylation was characterized in six lung cancer cell lines, and its clinical significance was analyzed using 298 formalin-fixed paraffin-embedded tissues and 26 fresh-frozen tissues from 324 NSCLC patients. MS-HRM (methylation-specific high-resolution melting) and EpiTYPERTM assays showed substantial hypermethylation of CpG island at the promoter region of HS3ST2 in six lung cancer cell lines. The silenced gene was demethylated and re-expressed by treatment with 5-aza-2′-deoxycytidine (5-Aza-dC). A promoter assay also showed the core promoter activity of HS3ST2 was regulated by methylation. Exogenous expression of HS3ST2 in lung cancer cells H460 and H23 inhibited cell migration, invasion, cell proliferation and whereas knockdown of HS3ST2 in NHBE cells induced cell migration, invasion, and cell proliferation in vitro. A negative correlation was observed between mRNA and methylation levels of HS3ST2 in 26 fresh-frozen tumors tissues (ρ = -0.51, P = 0.009; Spearman’s rank correlation). HS3ST2 hypermethylation was found in 95 (32%) of 298 primary NSCLCs. Patients with HS3ST2 hypermethylation in 193 node-negative stage I-II NSCLCs with a median follow-up period of 5.8 years had poor overall survival (hazard ratio = 2.12, 95% confidence interval = 1.25–3.58, P = 0.005) compared to those without HS3ST2 hypermethylation, after adjusting for age, sex, tumor size, adjuvant therapy, recurrence, and differentiation. Conclusions/ Significance The present study suggests that HS3ST2 hypermethylation may be an independent prognostic indicator for overall survival in node-negative stage I-II NSCLC. PMID:24265783
Sánchez, Juana; Bonet, M Luisa; Keijer, Jaap; van Schothorst, Evert M; Mölller, Ingrid; Chetrit, Carles; Martinez-Puig, Daniel; Palou, Andreu
2014-09-01
The aim of the study was to explore peripheral blood gene expression as a source of biomarkers of joint health improvement related to glycosaminoglycan (GAG) intake in humans. Healthy individuals with joint discomfort were enrolled in a randomized, double-blind, placebo-controlled intervention study in humans. Subjects ate control yoghurt or yoghurt supplemented with a recently authorized novel food in Europe containing hyaluronic acid (65 %) from rooster comb (Mobilee™ as commercial name) for 90 days. Effects on functional quality-of-life parameters related to joint health were assessed. Whole-genome microarray analysis of peripheral blood samples from a subset of 20 subjects (10 placebo and 10 supplemented) collected pre- and post-intervention was performed. Mobilee™ supplementation reduced articular pain intensity and synovial effusion and improved knee muscular strength indicators as compared to placebo. About 157 coding genes were differentially expressed in blood cells between supplemented and placebo groups post-intervention, but not pre-intervention (p < 0.05; fold change ≥1.2). Among them, a reduced gene expression of glucuronidase-beta (GUSB), matrix metallopeptidase 23B (MMP23B), xylosyltransferase II (XYLT2), and heparan sulfate 6-O-sulfotransferase 1 (HS6ST1) was found in the supplemented group. Correlation analysis indicated a direct relationship between blood cell gene expression of MMP23B, involved in the breakdown of the extracellular matrix, and pain intensity, and an inverse relationship between blood cell gene expression of HS6ST1, responsible for 6-O-sulfation of heparan sulfate, and indicators of knee muscular strength. Expression levels of specific genes in blood cells, in particular genes related to GAG metabolism and extracellular matrix dynamics, are potential biomarkers of beneficial effects on articular health.
Tran-Lundmark, Karin; Tran, Phan-Kiet; Paulsson-Berne, Gabrielle; Fridén, Vincent; Soininen, Raija; Tryggvason, Karl; Wight, Thomas N; Kinsella, Michael G; Borén, Jan; Hedin, Ulf
2009-01-01
Heparan sulfate (HS) has been proposed to be anti-atherogenic through inhibition of lipoprotein retention, inflammation, and smooth muscle cell proliferation. Perlecan is the predominant HS proteoglycan in the artery wall. Here, we investigated the role of perlecan HS chains using apoE null (ApoE0) mice that were cross-bred with mice expressing HS-deficient perlecan (Hspg2Δ3/Δ3). Morphometry of cross-sections from aortic roots and en face preparations of whole aortas revealed a significant decrease in lesion formation in ApoE0/Hspg2Δ3/Δ3 mice at both 15 and 33 weeks. In vitro, binding of labeled mouse triglyceride-rich lipoproteins and human LDL to total extracellular matrix, as well as to purified proteoglycans, prepared from ApoE0/Hspg2Δ3/Δ3 smooth muscle cells was reduced. In vivo, at 20 min influx of human 125I-LDL or mouse triglyceride-rich lipoproteins into the aortic wall was increased in ApoE0/Hspg2Δ3/Δ3 mice compared to ApoE0 mice. However, at 72 hours accumulation of 125I-LDL was similar in ApoE0/Hspg2Δ3/Δ3 and ApoE0 mice. Immunohistochemistry of lesions from ApoE0/Hspg2Δ3/Δ3 mice showed decreased staining for apoB and increased smooth muscle α-actin content, whereas accumulation of CD68-positive inflammatory cells was unchanged. We conclude that the perlecan HS chains are pro-atherogenic in mice, possibly through increased lipoprotein retention, altered vascular permeability, or other mechanisms. The ability of HS to inhibit smooth muscle cell growth may also influence development as well as instability of lesions. PMID:18596265
Tran-Lundmark, Karin; Tran, Phan-Kiet; Paulsson-Berne, Gabrielle; Fridén, Vincent; Soininen, Raija; Tryggvason, Karl; Wight, Thomas N; Kinsella, Michael G; Borén, Jan; Hedin, Ulf
2008-07-03
Heparan sulfate (HS) has been proposed to be antiatherogenic through inhibition of lipoprotein retention, inflammation, and smooth muscle cell proliferation. Perlecan is the predominant HS proteoglycan in the artery wall. Here, we investigated the role of perlecan HS chains using apoE null (ApoE0) mice that were cross-bred with mice expressing HS-deficient perlecan (Hspg2(Delta3/Delta3)). Morphometry of cross-sections from aortic roots and en face preparations of whole aortas revealed a significant decrease in lesion formation in ApoE0/Hspg2(Delta3/Delta3) mice at both 15 and 33 weeks. In vitro, binding of labeled mouse triglyceride-rich lipoproteins and human LDL to total extracellular matrix, as well as to purified proteoglycans, prepared from ApoE0/Hspg2(Delta3/Delta3) smooth muscle cells was reduced. In vivo, at 20 minutes influx of human (125)I-LDL or mouse triglyceride-rich lipoproteins into the aortic wall was increased in ApoE0/Hspg2(Delta3/Delta3) mice compared to ApoE0 mice. However, at 72 hours accumulation of (125)I-LDL was similar in ApoE0/Hspg2(Delta3/Delta3) and ApoE0 mice. Immunohistochemistry of lesions from ApoE0/Hspg2(Delta3/Delta3) mice showed decreased staining for apoB and increased smooth muscle alpha-actin content, whereas accumulation of CD68-positive inflammatory cells was unchanged. We conclude that the perlecan HS chains are proatherogenic in mice, possibly through increased lipoprotein retention, altered vascular permeability, or other mechanisms. The ability of HS to inhibit smooth muscle cell growth may also influence development as well as instability of lesions.
Minge, Daniel; Senkov, Oleg; Kaushik, Rahul; Herde, Michel K; Tikhobrazova, Olga; Wulff, Andreas B; Mironov, Andrey; van Kuppevelt, Toin H; Oosterhof, Arie; Kochlamazashvili, Gaga; Dityatev, Alexander; Henneberger, Christian
2017-02-01
Heparan sulfate (HS) proteoglycans represent a major component of the extracellular matrix and are critical for brain development. However, their function in the mature brain remains to be characterized. Here, acute enzymatic digestion of HS side chains was used to uncover how HSs support hippocampal function in vitro and in vivo. We found that long-term potentiation (LTP) of synaptic transmission at CA3-CA1 Schaffer collateral synapses was impaired after removal of highly sulfated HSs with heparinase 1. This reduction was associated with decreased Ca2+ influx during LTP induction, which was the consequence of a reduced excitability of CA1 pyramidal neurons. At the subcellular level, heparinase treatment resulted in reorganization of the distal axon initial segment, as detected by a reduction in ankyrin G expression. In vivo, digestion of HSs impaired context discrimination in a fear conditioning paradigm and oscillatory network activity in the low theta band after fear conditioning. Thus, HSs maintain neuronal excitability and, as a consequence, support synaptic plasticity and learning. © The Author 2017. Published by Oxford University Press.
Wu, Zhengliang L.; Lech, Miroslaw
2005-01-01
Chemical modification of biological molecules is a general mechanism for cellular regulation. A quantitative approach has been developed to measure the extent of modification on HS (heparan sulphates). Sulphation on HS by sulphotransferases leads to variable sulphation levels, which allows cells to tune their affinities to various extracellular proteins, including growth factors. With stable isotope labelling and HPLC-coupled MS, modification degrees at various O-sulphation sites could be determined. A bovine kidney HS sample was first saturated in vitro with 34S by an OST (O-sulphotransferase), then digested with nitrous acid and analysed with HPLC-coupled MS. The 34S-labelled oligosaccharides were identified based on their unique isotope clusters. The modification degrees at the sulphotransferase recognition sites were obtained by calculating the intensities of isotopic peaks in the isotope clusters. The modification degrees at 3-OST-1 and 6-OST-1 sites were examined in detail. This approach can also be used to study other types of chemical modifications on biological molecules. PMID:15743272
The Laminin Receptor Is a Cellular Attachment Receptor for Classical Swine Fever Virus
Chen, Jianing; He, Wen-Rui; Shen, Liang; Dong, Hong; Yu, Jiahui; Wang, Xiao; Yu, Shaoxiong; Li, Yongfeng; Li, Su; Luo, Yuzi; Sun, Yuan
2015-01-01
ABSTRACT Classical swine fever virus (CSFV) is the causative agent of classical swine fever (CSF), a highly contagious, economically important viral disease in many countries. The Erns and E2 envelope glycoproteins are responsible for the binding to and entry into the host cell by CSFV. To date, only one cellular receptor, heparan sulfate (HS), has been identified as being involved in CSFV attachment. HS is also present on the surface of various cells that are nonpermissive to CSFV. Hence, there must be another receptor(s) that has been unidentified to date. In this study, we used a set of small interfering RNAs (siRNAs) against a number of porcine cell membrane protein genes to screen cellular proteins involved in CSFV infection. This approach resulted in the identification of several proteins, and of these, the laminin receptor (LamR) has been demonstrated to be a cellular receptor for several viruses. Confocal analysis showed that LamR is colocalized with CSFV virions on the membrane, and a coimmunoprecipitation assay indicated that LamR interacts with the CSFV Erns protein. In inhibition assays, anti-LamR antibodies, soluble laminin, or LamR protein significantly inhibited CSFV infection in a dose-dependent manner. Transduction of PK-15 cells with a recombinant lentivirus expressing LamR yielded higher viral titers. Moreover, an attachment assay demonstrated that LamR functions during virus attachment. We also demonstrate that LamR acts as an alternative attachment receptor, especially in SK6 cells. These results indicate that LamR is a cellular attachment receptor for CSFV. IMPORTANCE Classical swine fever virus (CSFV) is the causative agent of classical swine fever (CSF), an economically important viral disease affecting the pig industry in many countries. To date, only heparan sulfate (HS) has been identified to be an attachment receptor for CSFV. Here, using RNA interference screening with small interfering RNAs (siRNAs) against a number of porcine membrane protein genes, we identified the laminin receptor (LamR) to be another attachment receptor. We demonstrate the involvement of LamR together with HS in virus attachment, and we elucidate the relationship between LamR and HS. LamR also serves as an attachment receptor for many viral pathogens, including dengue virus, a fatal human flavivirus. The study will help to enhance our understanding of the life cycle of flaviviruses and the development of antiviral strategies for flaviviruses. PMID:25694590
Vimentin Modulates Infectious Internalization of Human Papillomavirus 16 Pseudovirions.
Schäfer, Georgia; Graham, Lisa M; Lang, Dirk M; Blumenthal, Melissa J; Bergant Marušič, Martina; Katz, Arieh A
2017-08-15
Human papillomavirus (HPV) infection is the most common viral infection of the reproductive tract, with virtually all cases of cervical cancer being attributable to infection by oncogenic HPVs. However, the exact mechanism and receptors used by HPV to infect epithelial cells are controversial. The current entry model suggests that HPV initially attaches to heparan sulfate proteoglycans (HSPGs) at the cell surface, followed by conformational changes, cleavage by furin convertase, and subsequent transfer of the virus to an as-yet-unidentified high-affinity receptor. In line with this model, we established an in vitro infection system using the HSPG-deficient cell line pgsD677 together with HPV16 pseudovirions (HPV16-PsVs). While pgsD677 cells were nonpermissive for untreated HPV16-PsVs, furin cleavage of the particles led to a substantial increase in infection. Biochemical pulldown assays followed by mass spectrometry analysis showed that furin-precleaved HPV16-PsVs specifically interacted with surface-expressed vimentin on pgsD677 cells. We further demonstrated that both furin-precleaved and uncleaved HPV16-PsVs colocalized with surface-expressed vimentin on pgsD677, HeLa, HaCaT, and NIKS cells, while binding of incoming viral particles to soluble vimentin protein before infection led to a substantial decrease in viral uptake. Interestingly, decreasing cell surface vimentin by small interfering RNA (siRNA) knockdown in HeLa and NIKS cells significantly increased HPV16-PsV infectious internalization, while overexpression of vimentin had the opposite effect. The identification of vimentin as an HPV restriction factor enhances our understanding of the initial steps of HPV-host interaction and may lay the basis for the design of novel antiviral drugs preventing HPV internalization into epithelial cells. IMPORTANCE Despite HPV being a highly prevalent sexually transmitted virus causing significant disease burden worldwide, particularly cancer of the cervix, cell surface events preceding oncogenic HPV internalization are poorly understood. We herein describe the identification of surface-expressed vimentin as a novel molecule not previously implicated in the infectious internalization of HPV16. Contrary to our expectations, vimentin was found to act not as a receptor but rather as a restriction factor dampening the initial steps of HPV16 infection. These results importantly contribute to our current understanding of the molecular events during the infectious internalization of HPV16 and open a new direction in the development of alternative drugs to prevent HPV infection. Copyright © 2017 Schäfer et al.
Roy, Chandra Nath; Promjunyakul, Warunya; Hatakeyama, Hiroyasu; Gonda, Kohsuke; Imamura, Junji; Vasudevanpillai, Biju; Ohuchi, Noriaki; Kanzaki, Makoto; Higuchi, Hideo; Kaku, Mitsuo
2013-01-01
The mechanisms underlying the cellular entry of the HIV-1 Tat protein transduction domain (TatP) and the molecular information necessary to improve the transduction efficiency of TatP remain unclear due to the technical limitations for direct visualization of TatP's behavior in cells. Using confocal microscopy, total internal reflection fluorescence microscopy, and four-dimensional microscopy, we developed a single-molecule tracking assay for TatP labeled with quantum dots (QDs) to examine the kinetics of TatP initially and immediately before, at the beginning of, and immediately after entry into living cells. We report that even when the number of multivalent TatP (mTatP)-QDs bound to a cell was low, each single mTatP-QD first locally induced the cell's lateral transport machinery to move the mTatP-QD toward the center of the cell body upon cross-linking of heparan sulfate proteoglycans. The centripetal and lateral movements were linked to the integrity and flow of actomyosin and microtubules. Individual mTatP underwent lipid raft-mediated temporal confinement, followed by complete immobilization, which ultimately led to endocytotic internalization. However, bivalent TatP did not sufficiently promote either cell surface movement or internalization. Together, these findings provide clues regarding the mechanisms of TatP cell entry and indicate that increasing the valence of TatP on nanoparticles allows them to behave as cargo delivery nanomachines. PMID:23732912
Syndecan defines precise spindle orientation by modulating Wnt signaling in C. elegans.
Dejima, Katsufumi; Kang, Sukryool; Mitani, Shohei; Cosman, Pamela C; Chisholm, Andrew D
2014-11-01
Wnt signals orient mitotic spindles in development, but it remains unclear how Wnt signaling is spatially controlled to achieve precise spindle orientation. Here, we show that C. elegans syndecan (SDN-1) is required for precise orientation of a mitotic spindle in response to a Wnt cue. We find that SDN-1 is the predominant heparan sulfate (HS) proteoglycan in the early C. elegans embryo, and that loss of HS biosynthesis or of the SDN-1 core protein results in misorientation of the spindle of the ABar blastomere. The ABar and EMS spindles both reorient in response to Wnt signals, but only ABar spindle reorientation is dependent on a new cell contact and on HS and SDN-1. SDN-1 transiently accumulates on the ABar surface as it contacts C, and is required for local concentration of Dishevelled (MIG-5) in the ABar cortex adjacent to C. These findings establish a new role for syndecan in Wnt-dependent spindle orientation. © 2014. Published by The Company of Biologists Ltd.
Proliferative activity of elastin-like-peptides depends on charge and phase transition.
Yuan, Yuan; Koria, Piyush
2016-03-01
Elastin-like-peptides (ELPs) are stimulus-responsive protein-based polymers and are attractive biomaterials due to their biocompatibility and unique properties. This study shows that in addition to their physical properties, ELPs have biological activities that are conducive to tissue regeneration. Specifically, we found that ELPs induce fibroblast proliferation via cell surface heparan sulfate proteoglycans (HSPG). Furthermore, our data suggests that ELP based materials with differential proliferative potential can be designed by controlling the interaction of ELPs with HSPGs by incorporating either hydrophobic or positively charged residues within the ELP sequence. Fibroblast proliferation is important for granulation tissue formation which is important in chronic wounds as well as in healing of other tissues. The customizable biological activity of ELPs coupled with their unique physical properties will enable us to design novel, sustainable and cost effective therapies for different tissue regeneration applications. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 697-706, 2016. © 2015 Wiley Periodicals, Inc.
Identification and expression analysis of zebrafish glypicans during embryonic development.
Gupta, Mansi; Brand, Michael
2013-01-01
Heparan sulfate Proteoglycans (HSPG) are ubiquitous molecules with indispensable functions in various biological processes. Glypicans are a family of HSPG's, characterized by a Gpi-anchor which directs them to the cell surface and/or extracellular matrix where they regulate growth factor signaling during development and disease. We report the identification and expression pattern of glypican genes from zebrafish. The zebrafish genome contains 10 glypican homologs, as opposed to six in mammals, which are highly conserved and are phylogenetically related to the mammalian genes. Some of the fish glypicans like Gpc1a, Gpc3, Gpc4, Gpc6a and Gpc6b show conserved synteny with their mammalian cognate genes. Many glypicans are expressed during the gastrulation stage, but their expression becomes more tissue specific and defined during somitogenesis stages, particularly in the developing central nervous system. Existence of multiple glypican orthologs in fish with diverse expression pattern suggests highly specialized and/or redundant function of these genes during embryonic development.
Ebert, Antje D; Laussmann, Mareike; Wegehingel, Sabine; Kaderali, Lars; Erfle, Holger; Reichert, Jürgen; Lechner, Johannes; Beer, Hans-Dietmar; Pepperkok, Rainer; Nickel, Walter
2010-06-01
Fibroblast growth factor 2 (FGF2) is a potent mitogen that is exported from cells by an endoplasmic reticulum (ER)/Golgi-independent mechanism. Unconventional secretion of FGF2 occurs by direct translocation across plasma membranes, a process that depends on the phosphoinositide phosphatidylinositol 4,5-biphosphate (PI(4,5)P(2)) at the inner leaflet as well as heparan sulfate proteoglycans at the outer leaflet of plasma membranes; however, additional core and regulatory components of the FGF2 export machinery have remained elusive. Here, using a highly effective RNAi screening approach, we discovered Tec kinase as a novel factor involved in unconventional secretion of FGF2. Tec kinase does not affect FGF2 secretion by an indirect mechanism, but rather forms a heterodimeric complex with FGF2 resulting in phosphorylation of FGF2 at tyrosine 82, a post-translational modification shown to be essential for FGF2 membrane translocation to cell surfaces. Our findings suggest a crucial role for Tec kinase in regulating FGF2 secretion under various physiological conditions and, therefore, provide a new perspective for the development of a novel class of antiangiogenic drugs targeting the formation of the FGF2/Tec complex.
Heparin octasaccharide decoy liposomes inhibit replication of multiple viruses
Hendricks, Gabriel L.; Velazquez, Lourdes; Pham, Serena; Qaisar, Natasha; Delaney, James C.; Viswanathan, Karthik; Albers, Leila; Comolli, James C.; Shriver, Zachary; Knipe, David M.; Kurt-Jones, Evelyn A.; Fygenson, Deborah K.; Trevejo, Jose M.
2016-01-01
Heparan sulfate (HS) is a ubiquitous glycosaminoglycan that serves as a cellular attachment site for a number of significant human pathogens, including respiratory syncytial virus (RSV), human parainfluenza virus 3 (hPIV3), and herpes simplex virus (HSV). Decoy receptors can target pathogens by binding to the receptor pocket on viral attachment proteins, acting as ‘molecular sinks’ and preventing the pathogen from binding to susceptible host cells. Decoy receptors functionalized with HS could bind to pathogens and prevent infection, so we generated decoy liposomes displaying HS-octasaccharide (HS-octa). These decoy liposomes significantly inhibited RSV, hPIV3, and HSV infectivity in vitro to a greater degree than the original HS-octa building block. The degree of inhibition correlated with the density of HS-octa displayed on the liposome surface. Decoy liposomes with HS-octa inhibited infection of viruses to a greater extent than either full-length heparin or HS-octa alone. Decoy liposomes were effective when added prior to infection or following the initial infection of cells in vitro. By targeting the well-conserved receptor-binding sites of HS-binding viruses, decoy liposomes functionalized with HS-octa are a promising therapeutic antiviral agent and illustrate the utility of the liposome delivery platform. PMID:25637710
Wang, Yu-Ling; Kuo, Je-Hung; Lee, Shao-Chen; Liu, Jai-Shin; Hsieh, Yin-Cheng; Shih, Yu-Tsung; Chen, Chun-Jung; Chiu, Jeng-Jiann; Wu, Wen-Guey
2010-11-26
Cysteine-rich secretory proteins (CRISPs) have been identified as a toxin family in most animal venoms with biological functions mainly associated with the ion channel activity of cysteine-rich domain (CRD). CRISPs also bind to Zn(2+) at their N-terminal pathogenesis-related (PR-1) domain, but their function remains unknown. Interestingly, similar the Zn(2+)-binding site exists in all CRISP family, including those identified in a wide range of organisms. Here, we report that the CRISP from Naja atra (natrin) could induce expression of vascular endothelial cell adhesion molecules, i.e. intercellular adhesion molecule-1, vascular adhesion molecule-1, and E-selectin, to promote monocytic cell adhesion in a heparan sulfate (HS)- and Zn(2+)-dependent manner. Using specific inhibitors and small interfering RNAs, the activation mechanisms are shown to involve both mitogen-activated protein kinases and nuclear factor-κB. Biophysical characterization of natrin by using fluorescence, circular dichroism, and x-ray crystallographic methods further reveals the presence of two Zn(2+)-binding sites for natrin. The strong binding site is located near the putative Ser-His-Glu catalytic triad of the N-terminal domain. The weak binding site remains to be characterized, but it may modulate HS binding by enhancing its interaction with long chain HS. Our results strongly suggest that natrin may serve as an inflammatory modulator that could perturb the wound-healing process of the bitten victim by regulating adhesion molecule expression in endothelial cells. Our finding uncovers a new aspect of the biological role of CRISP family in immune response and is expected to facilitate future development of new therapeutic strategy for the envenomed victims.
Farach-Carson, Mary C; Warren, Curtis R; Harrington, Daniel A; Carson, Daniel D
2014-02-01
The extracellular matrix proteoglycan (ECM) perlecan, also known as heparan sulfate proteoglycan 2 or HSPG2, is one of the largest (>200 nm) and oldest (>550 M years) extracellular matrix molecules. In vertebrates, perlecan's five-domain structure contains numerous independently folding modules with sequence similarities to other ECM proteins, all connected like cars into one long, diverse complex train following a unique N-terminal domain I decorated with three long glycosaminoglycan chains, and an additional glycosaminoglycan attachment site in the C-terminal domain V. In lower invertebrates, perlecan is not typically a proteoglycan, possessing the majority of the core protein modules, but lacking domain I where the attachment sites for glycosaminoglycan chains are located. This suggests that uniting the heparan sulfate binding growth factor functions of domain I and the core protein functions of the rest of the molecule in domains II-V occurred later in evolution for a new functional purpose. In this review, we surveyed several decades of pertinent literature to ask a fundamental question: Why did nature design this protein uniquely as an extraordinarily long multifunctional proteoglycan with a single promoter regulating expression, rather than separating these functions into individual proteins that could be independently regulated? We arrived at the conclusion that the concentration of perlecan at functional borders separating tissues and tissue layers is an ancient key function of the core protein. The addition of the heparan sulfate chains in domain I likely occurred as an additional means of binding the core protein to other ECM proteins in territorial matrices and basement membranes, and as a means to reserve growth factors in an on-site depot to assist with rapid repair of those borders when compromised, such as would occur during wounding. We propose a function for perlecan that extends its role from that of an extracellular scaffold, as we previously suggested, to that of a critical agent for establishing and patrolling tissue borders in complex tissues in metazoans. We also propose that understanding these unique functions of the individual portions of the perlecan molecule can provide new insights and tools for engineering of complex multi-layered tissues including providing the necessary cues for establishing neotissue borders. © 2013.
Farach-Carson, Mary C.; Warren, Curtis R.; Harrington, Daniel A.; Carson, Daniel D.
2013-01-01
The extracellular matrix proteoglycan (ECM) perlecan, also known as heparan sulfate proteoglycan 2 or HSPG2, is one of the largest (>200 nm) and oldest (>550M years) extracellular matrix molecules. In vertebrates, perlecan’s five-domain structure contains numerous independently folding modules with sequence similarities to other ECM proteins, all connected like cars into one long, diverse complex train following a unique N-terminal domain I decorated with three long glycosaminoglycan chains, and an additional glycosaminoglycan attachment site in the C-terminal domain V. In lower invertebrates, perlecan is not typically a proteoglycan, possessing the majority of the core protein modules, but lacking domain I where the attachment sites for glycosaminoglycan chains are located. This suggests that uniting the heparan sulfate binding growth factor functions of domain I and the core protein functions of the rest of the molecule in domains II-V occurred later in evolution for a new functional purpose. In this review, we surveyed several decades of pertinent literature to ask a fundamental question: Why did nature design this protein uniquely as an extraordinarily long multifunctional proteoglycan with a single promoter regulating expression, rather than separating these functions into individual proteins that could be independently regulated? We arrived at the conclusion that the concentration of perlecan at functional borders separating tissues and tissue layers is an ancient key function of the core protein. The addition of the heparan sulfate chains in domain I likely occurred as an additional means of binding the core protein to other ECM proteins in territorial matrices and basement membranes, and as a means to reserve growth factors in an on-site depot to assist with rapid repair of those borders when compromised, such as would occur during wounding. We propose a function for perlecan that extends its role from that of an extracellular scaffold, as we previously suggested, to that of a critical agent for establishing and patrolling tissue borders in complex tissues in metazoans. We also propose that understanding these unique functions of the individual portions of the perlecan molecule can provide new insights and tools for engineering of complex multi-layered tissues including providing the necessary cues for establishing neotissue borders. PMID:24001398
Decreasing the metastatic potential in cancers--targeting the heparan sulfate proteoglycans.
Fjeldstad, K; Kolset, S O
2005-09-01
The heterogeneity of proteoglycans (PG)s contributes to their functional diversity. Many functions depend on their ability to bind and modulate the activity of components of the extracellular matrix (ECM). The ability of PGs to interact with other molecules, such as growth factors, is largely determined by the fine structure of the glycosaminoglycan (GAG) chains. Tumorigenesis is associated with changes in the PG synthesis. Heparan sulfate (HS) PGs are involved in several aspects of cancer biology including tumor progression, angiogenesis, and metastasis. PGs can have both tumor promoting and tumor suppressing activities depending on the protein core, the GAG attached, molecules they associate with, localization, the tumor subtype, stages, and degree of tumor differentiation. Perlecan is an angiogenic factor involved in tumor invasiveness. The C-terminal domain V of perlecan, named endorepellin, has however been shown to inhibit angiogenesis. Another angiogenic factor is endostatin, the COOH-terminal domain of the part-time PG collagen XVIII. Glypicans and syndecans may promote local cancer cell growth in some cancer tissues, but inhibit tissue invasion and metastasis in others. The GAG hyaluronan (HA) promotes cancer growth by providing a loose matrix for migrating tumor cells and mediates adhesion of cancer cells. HSPG degrading enzymes like heparanase, heparitinase, and other enzymes such as hyaluronidase and MMP are also important in tumor metastasis. Several different treatment strategies that target PGs have been developed. They have the potential to be effective in reducing tumor growth and inhibit the formation of metastases. PGs are also valuable tumor markers in several cancers.
Adams, Yvonne; Kuhnrae, Pongsak; Higgins, Matthew K; Ghumra, Ashfaq; Rowe, J Alexandra
2014-03-01
Adhesion interactions between Plasmodium falciparum-infected erythrocytes (IE) and human cells underlie the pathology of severe malaria. IE cytoadhere to microvascular endothelium or form rosettes with uninfected erythrocytes to survive in vivo by sequestering IE in the microvasculature and avoiding splenic clearance mechanisms. Both rosetting and cytoadherence are mediated by the parasite-derived IE surface protein family Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1). Rosetting and cytoadherence have been widely studied as separate entities; however, the ability of rosetting P. falciparum strains to cytoadhere has received little attention. Here, we show that IE of the IT/R29 strain expressing a rosette-mediating PfEMP1 variant (IT4var09) cytoadhere in vitro to a human brain microvascular endothelial cell line (HBEC-5i). Cytoadherence was inhibited by heparin and by treatment of HBEC-5i with heparinase III, suggesting that the endothelial receptors for IE binding are heparan sulfate proteoglycans. Antibodies to the N-terminal regions of the IT4var09 PfEMP1 variant (NTS-DBL1α and DBL2γ domains) specifically inhibited and reversed cytoadherence down to low concentrations (<10 μg/ml of total IgG). Surface plasmon resonance experiments showed that the NTS-DBLα and DBL2γ domains bind strongly to heparin, with half-maximal binding at a concentration of ∼0.5 μM in both cases. Therefore, cytoadherence of IT/R29 IE is distinct from rosetting, which is primarily mediated by NTS-DBL1α interactions with complement receptor 1. These data show that IT4var09-expressing parasites are capable of dual interactions with both endothelial cells and uninfected erythrocytes via distinct receptor-ligand interactions.
Ferreras, Cristina; Rushton, Graham; Cole, Claire L.; Babur, Muhammad; Telfer, Brian A.; van Kuppevelt, Toin H.; Gardiner, John M.; Williams, Kaye J.; Jayson, Gordon C.; Avizienyte, Egle
2012-01-01
Fibroblast growth factor 2 (FGF2) and vascular endothelial growth factor 165 (VEGF165) are potent pro-angiogenic growth factors that play a pivotal role in tumor angiogenesis. The activity of these growth factors is regulated by heparan sulfate (HS), which is essential for the formation of FGF2/FGF receptor (FGFR) and VEGF165/VEGF receptor signaling complexes. However, the structural characteristics of HS that determine activation or inhibition of such complexes are only partially defined. Here we show that ovarian tumor endothelium displays high levels of HS sequences that harbor glucosamine 6-O-sulfates when compared with normal ovarian vasculature where these sequences are also detected in perivascular area. Reduced HS 6-O-sulfotransferase 1 (HS6ST-1) or 6-O-sulfotransferase 2 (HS6ST-2) expression in endothelial cells impacts upon the prevalence of HS 6-O-sulfate moieties in HS sequences, which consist of repeating short, highly sulfated S domains interspersed by transitional N-acetylated/N-sulfated domains. 1–40% reduction in 6-O-sulfates significantly compromises FGF2- and VEGF165-induced endothelial cell sprouting and tube formation in vitro and FGF2-dependent angiogenesis in vivo. Moreover, HS on wild-type neighboring endothelial or smooth muscle cells fails to restore endothelial cell sprouting and tube formation. The affinity of FGF2 for HS with reduced 6-O-sulfation is preserved, although FGFR1 activation is inhibited correlating with reduced receptor internalization. These data show that 6-O-sulfate moieties in endothelial HS are of major importance in regulating FGF2- and VEGF165-dependent endothelial cell functions in vitro and in vivo and highlight HS6ST-1 and HS6ST-2 as potential targets of novel antiangiogenic agents. PMID:22927437
Glycosaminoglycan-Mediated Downstream Signaling of CXCL8 Binding to Endothelial Cells
Derler, Rupert; Weber, Corinna; Strutzmann, Elisabeth; Miller, Ingrid; Kungl, Andreas
2017-01-01
The recruitment of leukocytes, mediated by endothelium bound chemokine gradients, is a vital process in inflammation. The highly negatively charged, unbranched polysaccharide family of glycosaminoglycans (GAGs), such as heparan sulfate and chondroitin sulfate mediate chemokine immobilization. Specifically the binding of CXCL8 (interleukin 8) to GAGs on endothelial cell surfaces is known to regulate neutrophil recruitment. Currently, it is not clear if binding of CXCL8 to GAGs leads to endothelial downstream signaling in addition to the typical CXCR1/CXCR2 (C-X-C motif chemokine receptor 1 and 2)-mediated signaling which activates neutrophils. Here we have investigated the changes in protein expression of human microvascular endothelial cells induced by CXCL8. Tumor necrosis factor alpha (TNFα) stimulation was used to mimic an inflammatory state which allowed us to identify syndecan-4 (SDC4) as the potential proteoglycan co-receptor of CXCL8 by gene array, real-time PCR and flow cytometry experiments. Enzymatic GAG depolymerization via heparinase III and chondroitinase ABC was used to emulate the effect of glycocalyx remodeling on CXCL8-induced endothelial downstream signaling. Proteomic analyses showed changes in the expression pattern of a number of endothelial proteins such as Zyxin and Caldesmon involved in cytoskeletal organization, cell adhesion and cell mobility. These results demonstrate for the first time a potential role of GAG-mediated endothelial downstream signaling in addition to the well-known CXCL8-CXCR1/CXCR2 signaling pathways in neutrophils. PMID:29207576
Compositional analysis and structural elucidation of glycosaminoglycans in chicken eggs
Liu, Zhangguo; Zhang, Fuming; Li, Lingyun; Li, Guoyun; He, Wenqing; Linhardt, Robert J.
2014-01-01
Glycosaminoglycans (GAGs) have numerous applications in the fields of pharmaceuticals, cosmetics, nutraceuticals, and foods. GAGs are also critically important in the developmental biology of all multicellular animals. GAGs were isolated from chicken egg components including yolk, thick egg white, thin egg white, membrane, calcified shell matrix supernatant, and shell matrix deposit. Disaccharide compositional analysis was performed using ultra high-performance liquid chromatography-mass spectrometry. The results of these analyses showed that all four families of GAGs were detected in all egg components. Keratan sulfate was found in egg whites (thick and thin) and shell matrix (calcified shell matrix supernatant and deposit) with high level. Chondroitin sulfates were much more plentiful in both shell matrix components and membrane. Hyaluronan was plentiful in both shell matrix components and membrane, but were only present in a trace of quantities in the yolk. Heparan sulfate was plentiful in the shell matrix deposit but was present in a trace of quantities in the egg content components (yolk, thick and thin egg whites). Most of the chondroitin and heparan sulfate disaccharides were present in the GAGs found in chicken eggs with the exception of chondroitin and heparan sulfate 2,6-disulfated disaccharides. Both CS and HS in the shell matrix deposit contained the most diverse chondroitin and heparan sulfate disaccharide compositions. Eggs might provide a potential new source of GAGs. PMID:25218438
Hsieh, Po-Hung; Xu, Yongmei; Keire, David A; Liu, Jian
2014-01-01
Heparan sulfate and heparin are highly sulfated polysaccharides that consist of a repeating disaccharide unit of glucosamine and glucuronic or iduronic acid. The 2-O-sulfated iduronic acid (IdoA2S) residue is commonly found in heparan sulfate and heparin; however, 2-O-sulfated glucuronic acid (GlcA2S) is a less abundant monosaccharide (∼<5% of total saccharides). Here, we report the synthesis of three GlcA2S-containing hexasaccharides using a chemoenzymatic approach. For comparison purposes, additional IdoA2S-containing hexasaccharides were synthesized. Nuclear magnetic resonance analyses were performed to obtain full chemical shift assignments for the GlcA2S- and IdoA2S-hexasaccharides. These data show that GlcA2S is a more structurally rigid saccharide residue than IdoA2S. The antithrombin (AT) binding affinities of a GlcA2S- and an IdoA2S-hexasaccharide were determined by affinity co-electrophoresis. In contrast to IdoA2S-hexasaccharides, the GlcA2S-hexasaccharide does not bind to AT, confirming that the presence of IdoA2S is critically important for the anticoagulant activity. The availability of pure synthetic GlcA2S-containing oligosaccharides will allow the investigation of the structure and activity relationships of individual sites in heparin or heparan sulfate. PMID:24770491
Senni, Karim; Gueniche, Farida; Changotade, Sylvie; Septier, Dominique; Sinquin, Corinne; Ratiskol, Jacqueline; Lutomski, Didier; Godeau, Gaston; Guezennec, Jean; Colliec-Jouault, Sylvia
2013-04-23
Biopolymers produced by marine organisms can offer useful tools for regenerative medicine. Particularly, HE800 exopolysaccharide (HE800 EPS) secreted by a deep-sea hydrothermal bacterium displays an interesting glycosaminoglycan-like feature resembling hyaluronan. Previous studies demonstrated its effectiveness to enhance in vivo bone regeneration and to support osteoblastic cell metabolism in culture. Thus, in order to assess the usefulness of this high-molecular weight polymer in tissue engineering and tissue repair, in vitro reconstructed connective tissues containing HE800 EPS were performed. We showed that this polysaccharide promotes both collagen structuring and extracellular matrix settle by dermal fibroblasts. Furthermore, from the native HE800 EPS, a low-molecular weight sulfated derivative (HE800 DROS) displaying chemical analogy with heparan-sulfate, was designed. Thus, it was demonstrated that HE800 DROS mimics some properties of heparan-sulfate, such as promotion of fibroblast proliferation and inhibition of matrix metalloproteinase (MMP) secretion. Therefore, we suggest that the HE800EPS family can be considered as an innovative biotechnological source of glycosaminoglycan-like compounds useful to design biomaterials and drugs for tissue engineering and repair.
Noborn, Fredrik; Gomez Toledo, Alejandro; Green, Anders; Nasir, Waqas; Sihlbom, Carina; Nilsson, Jonas; Larson, Göran
2016-10-03
Heparan sulfate (HS) and chondroitin sulfate (CS) are complex polysaccharides that regulate important biological pathways in virtually all metazoan organisms. The polysaccharides often display opposite effects on cell functions with HS and CS structural motifs presenting unique binding sites for specific ligands. Still, the mechanisms by which glycan biosynthesis generates complex HS and CS polysaccharides required for the regulation of mammalian physiology remain elusive. Here we present a glycoproteomic approach that identifies and differentiates between HS and CS attachment sites and provides identity to the core proteins. Glycopeptides were prepared from perlecan, a complex proteoglycan known to be substituted with both HS and CS chains, further digested with heparinase or chondroitinase ABC to reduce the HS and CS chain lengths respectively, and thereafter analyzed by nLC-MS/MS. This protocol enabled the identification of three consensus HS sites and one hybrid site, carrying either a HS or a CS chain. Inspection of the amino acid sequence at the hybrid attachment locus indicates that certain peptide motifs may encode for the chain type selection process. This analytical approach will become useful when addressing fundamental questions in basic biology specifically in elucidating the functional roles of site-specific glycosylations of proteoglycans.
Senni, Karim; Gueniche, Farida; Changotade, Sylvie; Septier, Dominique; Sinquin, Corinne; Ratiskol, Jacqueline; Lutomski, Didier; Godeau, Gaston; Guezennec, Jean; Colliec-Jouault, Sylvia
2013-01-01
Biopolymers produced by marine organisms can offer useful tools for regenerative medicine. Particularly, HE800 exopolysaccharide (HE800 EPS) secreted by a deep-sea hydrothermal bacterium displays an interesting glycosaminoglycan-like feature resembling hyaluronan. Previous studies demonstrated its effectiveness to enhance in vivo bone regeneration and to support osteoblastic cell metabolism in culture. Thus, in order to assess the usefulness of this high-molecular weight polymer in tissue engineering and tissue repair, in vitro reconstructed connective tissues containing HE800 EPS were performed. We showed that this polysaccharide promotes both collagen structuring and extracellular matrix settle by dermal fibroblasts. Furthermore, from the native HE800 EPS, a low-molecular weight sulfated derivative (HE800 DROS) displaying chemical analogy with heparan-sulfate, was designed. Thus, it was demonstrated that HE800 DROS mimics some properties of heparan-sulfate, such as promotion of fibroblast proliferation and inhibition of matrix metalloproteinase (MMP) secretion. Therefore, we suggest that the HE800EPS family can be considered as an innovative biotechnological source of glycosaminoglycan-like compounds useful to design biomaterials and drugs for tissue engineering and repair. PMID:23612369
Deligny, Audrey; Denys, Agnès; Marcant, Adeline; Melchior, Aurélie; Mazurier, Joël; van Kuppevelt, Toin H; Allain, Fabrice
2010-01-15
Cyclophilin B (CyPB) induces migration and adhesion of T lymphocytes via a mechanism that requires interaction with 3-O-sulfated heparan sulfate (HS). HS biosynthesis is a complex process with many sulfotransferases involved. N-Deacetylases/N-sulfotransferases are responsible for N-sulfation, which is essential for subsequent modification steps, whereas 3-O-sulfotransferases (3-OSTs) catalyze the least abundant modification. These enzymes are represented by several isoforms, which differ in term of distribution pattern, suggesting their involvement in making tissue-specific HS. To elucidate how the specificity of CyPB binding is determined, we explored the relationships between the expression of these sulfotransferases and the generation of HS motifs with CyPB-binding properties. We demonstrated that high N-sulfate density and the presence of 2-O- and 3-O-sulfates determine binding of CyPB, as evidenced by competitive experiments with heparin derivatives, soluble HS, and anti-HS antibodies. We then showed that target cells, i.e. CD4+ lymphocyte subsets, monocytes/macrophages, and related cell lines, specifically expressed high levels of NDST2 and 3-OST3 isoforms. Silencing the expression of NDST1, NDST2, 2-OST, and 3-OST3 by RNA interference efficiently decreased binding and activity of CyPB, thus confirming their involvement in the biosynthesis of binding sequences for CyPB. Moreover, we demonstrated that NDST1 was able to partially sulfate exogenous substrate in the absence of NDST2 but not vice versa, suggesting that both isoenzymes do not have redundant activities but do have rather complementary activities in making N-sulfated sequences with CyPB-binding properties. Altogether, these results suggest a regulatory mechanism in which cell type-specific expression of certain HS sulfotransferases determines the specific binding of CyPB to target cells.
Deligny, Audrey; Denys, Agnès; Marcant, Adeline; Melchior, Aurélie; Mazurier, Joël; van Kuppevelt, Toin H.; Allain, Fabrice
2010-01-01
Cyclophilin B (CyPB) induces migration and adhesion of T lymphocytes via a mechanism that requires interaction with 3-O-sulfated heparan sulfate (HS). HS biosynthesis is a complex process with many sulfotransferases involved. N-Deacetylases/N-sulfotransferases are responsible for N-sulfation, which is essential for subsequent modification steps, whereas 3-O-sulfotransferases (3-OSTs) catalyze the least abundant modification. These enzymes are represented by several isoforms, which differ in term of distribution pattern, suggesting their involvement in making tissue-specific HS. To elucidate how the specificity of CyPB binding is determined, we explored the relationships between the expression of these sulfotransferases and the generation of HS motifs with CyPB-binding properties. We demonstrated that high N-sulfate density and the presence of 2-O- and 3-O-sulfates determine binding of CyPB, as evidenced by competitive experiments with heparin derivatives, soluble HS, and anti-HS antibodies. We then showed that target cells, i.e. CD4+ lymphocyte subsets, monocytes/macrophages, and related cell lines, specifically expressed high levels of NDST2 and 3-OST3 isoforms. Silencing the expression of NDST1, NDST2, 2-OST, and 3-OST3 by RNA interference efficiently decreased binding and activity of CyPB, thus confirming their involvement in the biosynthesis of binding sequences for CyPB. Moreover, we demonstrated that NDST1 was able to partially sulfate exogenous substrate in the absence of NDST2 but not vice versa, suggesting that both isoenzymes do not have redundant activities but do have rather complementary activities in making N-sulfated sequences with CyPB-binding properties. Altogether, these results suggest a regulatory mechanism in which cell type-specific expression of certain HS sulfotransferases determines the specific binding of CyPB to target cells. PMID:19940140
Towards molecular modeling of the impact of heparin-derived oligosaccharides on hIFN-γ binding
NASA Astrophysics Data System (ADS)
Lilkova, E.; Petkov, P.; Ilieva, N.; Litov, L.
2015-10-01
Human interferon gamma (hIFN-γ) is an important signalling molecule, which plays a key role in the formation and modulation of immune response. The role of the cytokine C-termini in the formation of a complex with the extracellular receptor is still controversial due to the lack of structural information about this domain. Moreover, the C-termini are also responsible for the high affinity interaction of hIFN-γ with the glycosaminoglicans heparan sulfate and heparin. This interaction can drastically change the properties and behaviour of the protein. We performed molecular dynamics simulations in order to model the structure of the hIFN-γ C-terminal part and the interaction of the cytokine with heparin-derived oligosaccharides. For this purpose we reconstructed the missing C-terminal amino acid residues and performed folding simulations to determine their conformation. In order to simulate the interaction with heparin-like fragments, we developed CHARMM 36 compatible force field for the sulfamate anion group that is present in the glucosamine sugar to complete the heparin and heparan sulfate force field. The new topology and parameters reproduce the available experimental structural properties of heparin-like fragments. The simulations show that the oligosaccharides quickly bind the IFN-γ C-termini and reduce their solvent accessible surface area.
The glycocalyx and its significance in human medicine.
Tarbell, J M; Cancel, L M
2016-07-01
Cells are covered by a surface layer of glycans that is referred to as the 'glycocalyx'. In this review, we focus on the role of the glycocalyx in vascular diseases (atherosclerosis, stroke, hypertension, kidney disease and sepsis) and cancer. The glycocalyx and its principal glycosaminoglycans [heparan sulphate (HS) and hyaluronic acid (HA)] and core proteins (syndecans and glypicans) are degraded in vascular diseases, leading to a breakdown of the vascular permeability barrier, enhanced access of leucocytes to the arterial intima that propagate inflammation and alteration of endothelial mechanotransduction mechanisms that protect against disease. By contrast, the glycocalyx on cancer cells is generally robust, promoting integrin clustering and growth factor signalling, and mechanotransduction of interstitial flow shear stress that is elevated in tumours to upregulate matrix metalloproteinase release which enhances cell motility and metastasis. HS and HA are consistently elevated on cancer cells and are associated with tumour growth and metastasis. Later, we will review the agents that might be used to enhance or protect the glycocalyx to combat vascular disease, as well as a different set of compounds that can degrade the cancer cell glycocalyx to suppress cell growth and metastasis. It is clear that what is beneficial for either vascular disease or cancer will not be so for the other. The overarching conclusions are that (i) the importance of the glycocalyx in human medicine is only beginning to be recognized, and (ii) more detailed studies of glycocalyx involvement in vascular diseases and cancer will lead to novel treatment modalities. © 2016 The Association for the Publication of the Journal of Internal Medicine.
Molecular targets and signaling pathways regulated by nuclear translocation of syndecan-1.
Szatmári, Tünde; Mundt, Filip; Kumar-Singh, Ashish; Möbus, Lena; Ötvös, Rita; Hjerpe, Anders; Dobra, Katalin
2017-12-08
The cell-surface heparan sulfate proteoglycan syndecan-1 is important for tumor cell proliferation, migration, and cell cycle regulation in a broad spectrum of malignancies. Syndecan-1, however, also translocates to the cell nucleus, where it might regulate various molecular functions. We used a fibrosarcoma model to dissect the functions of syndecan-1 related to the nucleus and separate them from functions related to the cell-surface. Nuclear translocation of syndecan-1 hampered the proliferation of fibrosarcoma cells compared to the mutant lacking nuclear localization signal. The growth inhibitory effect of nuclear syndecan-1 was accompanied by significant accumulation of cells in the G0/G1 phase, which indicated a possible G1/S phase arrest. We implemented multiple, unsupervised global transcriptome and proteome profiling approaches and combined them with functional assays to disclose the molecular mechanisms that governed nuclear translocation and its related functions. We identified genes and pathways related to the nuclear compartment with network enrichment analysis of the transcriptome and proteome. The TGF-β pathway was activated by nuclear syndecan-1, and three genes were significantly altered with the deletion of nuclear localization signal: EGR-1 (early growth response 1), NEK11 (never-in-mitosis gene a-related kinase 11), and DOCK8 (dedicator of cytokinesis 8). These candidate genes were coupled to growth and cell-cycle regulation. Nuclear translocation of syndecan-1 influenced the activity of several other transcription factors, including E2F, NFκβ, and OCT-1. The transcripts and proteins affected by syndecan-1 showed a striking overlap in their corresponding biological processes. These processes were dominated by protein phosphorylation and post-translation modifications, indicative of alterations in intracellular signaling. In addition, we identified molecules involved in the known functions of syndecan-1, including extracellular matrix organization and transmembrane transport. Collectively, abrogation of nuclear translocation of syndecan-1 resulted in a set of changes clustering in distinct patterns, which highlighted the functional importance of nuclear syndecan-1 in hampering cell proliferation and the cell cycle. This study emphasizes the importance of the localization of syndecan-1 when considering its effects on tumor cell fate.
Heparosan-glucuronate 5-epimerase: Molecular cloning and characterization of a novel enzyme.
Mochizuki, Hideo; Yamagishi, Kiwamu; Suzuki, Kiyoshi; Kim, Yeong Shik; Kimata, Koji
2015-07-01
Iduronic acid (IdoA) is a critical component of heparan sulfate in its interaction with functional proteins. Heparosan-N-sulfate-glucuronate 5-epimerase (HNSG-5epi) converts d-glucuronic acid (GlcA) residues in N-sulfated heparosan (NS-heparosan), as an intermediate in heparan sulfate biosynthesis, to IdoA. In the present study, the authors discovered a different 5-epimerase, designated HG-5epi (heparosan-glucuronate 5-epimerase), that is involved in acharan sulfate biosynthesis and possesses novel substrate specificity. A candidate cDNA of HG-5epi was cloned from the cDNA library of Achatina fulica. The cloned cDNA contained a whole coding region that predicts a type II transmembrane protein composed of 601 amino acid residues. The amino acid sequence of HG-5epi is homologous to that of HNSG-5epi. Recombinant HG-5epi was expressed in insect cells and its enzymatic properties characterized. As expected, HG-5epi epimerizes GlcA residues in heparosan, but not in NS-heparosan. Conversion of IdoA to GlcA was also catalyzed by HG-5epi when completely desulfated N-acetylated heparin was used as the substrate, indicating a reversible reaction mechanism. At equilibrium of the epimerization, the proportion of IdoA in the reaction product reached up to 30% of total hexuronic acid. To our knowledge, this is the first report to describe an enzyme that catalyzes the epimerization of non-sulfated heparosan. This new enzyme may be applied to the study of synthetic heparan sulfate-related polysaccharides having certain biological and pharmacological activities. In addition, a new method using anion-exchange HPLC connected to a post-column fluorescent labeling system was developed for analyzing hexuronic acid isomers. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Kibbe, M R; Murdock, A; Wickham, T; Lizonova, A; Kovesdi, I; Nie, S; Shears, L; Billiar, T R; Tzeng, E
2000-02-01
Adenovirus is widely used as a vector for gene transfer to the vasculature. However, the efficiency of these vectors can be limited by ineffective viral-target cell interactions. Viral attachment, which largely determines adenoviral tropism, is mediated through binding of the adenoviral fiber coat protein to the Coxsackievirus and adenovirus receptor, while internalization follows binding of the adenoviral RGD motif to alpha(v)-integrin receptors. Modifications of the fiber coat protein sequence have been successful for targeting the adenovirus to more prevalent receptors in the vasculature, including heparan sulfate-containing receptors and alpha(v)-integrin receptors. Modified adenoviral vectors targeted to receptors more prevalent in the vasculature result in an increased transfer efficiency of the virus in vitro and in vivo even in the presence of clinically relevant doses of heparin. We tested 2 modified E1- and E3-deleted Ad5 type adenoviral vectors containing the beta-galactosidase gene. AdZ.F(pK7) contains multiple positively charged lysines in the fiber coat protein that target the adenovirus to heparan sulfate receptors, while AdZ.F(RGD) contains an RGD integrin-binding sequence in the fiber coat protein that allows binding to alpha(v)-integrin receptors. The gene transfer efficiency of these modified viruses was compared in rat aortic smooth muscle cells in vitro and in an in vivo porcine model of balloon-induced arterial injury. Because of the use of heparin during most vascular surgical procedures and the concern that heparin might interfere with the binding of AdZ.F(pK7) to heparan sulfate receptors, the effect of heparin on the in vitro and in vivo transfer efficiency of these 2 modified adenoviruses was evaluated. In vitro infection of rat aortic smooth muscle cells with AdZ.F(pK7) and AdZ.F(RGD) resulted in significantly higher levels of beta-galactosidase expression compared with the unmodified adenovirus (mean +/- SEM, 1766.3 +/- 89.1 and 44.8 +/- 3.4 vs 10.1 +/- 0.7 mU per milligram of protein; P<.001). Following heparin administration, the gene transfer efficiency achieved with AdZ.F(pK7) diminished slightly in a concentration-dependent manner. However, the transfer efficiency was still greater than with the unmodified virus (mean +/- SEM, 1342.3 +/- 101.8 vs 4.8 +/- 0.4 mU per milligram of protein; P<.001). In vivo, following injury to the pig iliac artery with a 4F Fogarty balloon catheter, we found that AdZ.F(pK7) transduced the artery approximately 35-fold more efficiently than AdZ.F and 3-fold more efficiently than AdZ.F(RGD) following the administration of intravenous heparin, 100 U/kg body weight, and heparinized saline irrigation. Modifications of the adenovirus that lead to receptor targeting resulted in significantly improved gene transfer efficiencies. These improvements in transfer efficiencies observed with the modified vectors decreased slightly in the presence of heparin. However, AdZ.F(pK7) was still superior to AdZ.F(RGD) and AdZ.F despite heparin administration. These data demonstrate that modifications of adenoviral vectors that enhance binding to heparan sulfate receptors significantly improve gene transfer efficiency even in the presence of heparin and suggest an approach to optimize gene transfer into blood vessels.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Djovkar, A.; Gressner, A.M.
1987-03-01
The synthesis of proteoheparan sulfate in hepatocytes is positively regulated under acute-phase conditions produced either by turpentine or deep back incision. In both cases the incorporation of (/sup 35/S)sulfate and (/sup 14/C)glucosamine is doubled during a 4-h incubation period if compared with control rat hepatocytes. Neither the fractional secretion rate of heparan sulfate into the medium (less than 0.1 of cell-associated glycosaminoglycans) nor the composition of newly formed proteoglycans in hepatocytes are affected during acute phase reaction.
Regulation of Hedgehog Signalling Inside and Outside the Cell
Ramsbottom, Simon A.; Pownall, Mary E.
2016-01-01
The hedgehog (Hh) signalling pathway is conserved throughout metazoans and plays an important regulatory role in both embryonic development and adult homeostasis. Many levels of regulation exist that control the release, reception, and interpretation of the hedgehog signal. The fatty nature of the Shh ligand means that it tends to associate tightly with the cell membrane, and yet it is known to act as a morphogen that diffuses to elicit pattern formation. Heparan sulfate proteoglycans (HSPGs) play a major role in the regulation of Hh distribution outside the cell. Inside the cell, the primary cilium provides an important hub for processing the Hh signal in vertebrates. This review will summarise the current understanding of how the Hh pathway is regulated from ligand production, release, and diffusion, through to signal reception and intracellular transduction. PMID:27547735
Heparin octasaccharide decoy liposomes inhibit replication of multiple viruses.
Hendricks, Gabriel L; Velazquez, Lourdes; Pham, Serena; Qaisar, Natasha; Delaney, James C; Viswanathan, Karthik; Albers, Leila; Comolli, James C; Shriver, Zachary; Knipe, David M; Kurt-Jones, Evelyn A; Fygenson, Deborah K; Trevejo, Jose M; Wang, Jennifer P; Finberg, Robert W
2015-04-01
Heparan sulfate (HS) is a ubiquitous glycosaminoglycan that serves as a cellular attachment site for a number of significant human pathogens, including respiratory syncytial virus (RSV), human parainfluenza virus 3 (hPIV3), and herpes simplex virus (HSV). Decoy receptors can target pathogens by binding to the receptor pocket on viral attachment proteins, acting as 'molecular sinks' and preventing the pathogen from binding to susceptible host cells. Decoy receptors functionalized with HS could bind to pathogens and prevent infection, so we generated decoy liposomes displaying HS-octasaccharide (HS-octa). These decoy liposomes significantly inhibited RSV, hPIV3, and HSV infectivity in vitro to a greater degree than the original HS-octa building block. The degree of inhibition correlated with the density of HS-octa displayed on the liposome surface. Decoy liposomes with HS-octa inhibited infection of viruses to a greater extent than either full-length heparin or HS-octa alone. Decoy liposomes were effective when added prior to infection or following the initial infection of cells in vitro. By targeting the well-conserved receptor-binding sites of HS-binding viruses, decoy liposomes functionalized with HS-octa are a promising therapeutic antiviral agent and illustrate the utility of the liposome delivery platform. Copyright © 2015 Elsevier B.V. All rights reserved.
Additionally sulfated xylomannan sulfates from Scinaia hatei and their antiviral activities.
Ray, Sayani; Pujol, Carlos A; Damonte, Elsa B; Ray, Bimalendu
2015-10-20
Herpes simplex viruses (HSVs) display affinity for cell-surface heparan sulfate proteoglycans with biological relevance in virus entry. This study demonstrates the potential of chemically engineered sulfated xylomannans from Scinaia hatei as antiHSV drug candidate. Particularly, a dimethylformamide -SO3/pyridine based procedure has been employed for the generation of anionic polysaccharides. This one-step procedure has the power of providing a spectrum of xylomannans with varying molecular masses (<12-74kDa), sulfate content (1-50%) and glycosyl composition. Especially, the sulfated xylomannans S1F1 and S2F1 possessed altered activity against HSV-1 and HSV-2 compared to the parental compound (F1) and that too in the absence of drug-induced cytotoxicity. Regarding methodological facet, the directive decoration of hydroxyl functionality with sulfate group plus changes in the molecular mass and sugar composition during isolation by the used reagent opens a door for the production of new molecular entity with altered biological activity from other natural sources. Copyright © 2015 Elsevier Ltd. All rights reserved.
Pu, Jiarui; Mei, Hong; Zhao, Jun; Huang, Kai; Zeng, Fuqing; Tong, Qiangsong
2012-01-01
Heparanase (HPA), an endo-h-D-glucuronidase that cleaves the heparan sulfate chain of heparan sulfate proteoglycans, is overexpressed in majority of human cancers. Recent evidence suggests that small interfering RNA (siRNA) induces transcriptional gene silencing (TGS) in human cells. In this study, transfection of siRNA against −9/+10 bp (siH3), but not −174/−155 bp (siH1) or −134/−115 bp (siH2) region relative to transcription start site (TSS) locating at 101 bp upstream of the translation start site, resulted in TGS of heparanase in human prostate cancer, bladder cancer, and gastric cancer cells in a sequence-specific manner. Methylation-specific PCR and bisulfite sequencing revealed no DNA methylation of CpG islands within heparanase promoter in siH3-transfected cells. The TGS of heparanase did not involve changes of epigenetic markers histone H3 lysine 9 dimethylation (H3K9me2), histone H3 lysine 27 trimethylation (H3K27me3) or active chromatin marker acetylated histone H3 (AcH3). The regulation of alternative splicing was not involved in siH3-mediated TGS. Instead, siH3 interfered with transcription initiation via decreasing the binding of both RNA polymerase II and transcription factor II B (TFIIB), but not the binding of transcription factors Sp1 or early growth response 1, on the heparanase promoter. Moreover, Argonaute 1 and Argonaute 2 facilitated the decreased binding of RNA polymerase II and TFIIB on heparanase promoter, and were necessary in siH3-induced TGS of heparanase. Stable transfection of the short hairpin RNA construct targeting heparanase TSS (−9/+10 bp) into cancer cells, resulted in decreased proliferation, invasion, metastasis and angiogenesis of cancer cells in vitro and in athymic mice models. These results suggest that small RNAs targeting TSS can induce TGS of heparanase via interference with transcription initiation, and significantly suppress the tumor growth, invasion, metastasis and angiogenesis of cancer cells. PMID:22363633
Regenerative effects of peptide nanofibers in an experimental model of Parkinson's disease.
Sever, Melike; Turkyilmaz, Mesut; Sevinc, Cansu; Cakir, Aysen; Ocalan, Busra; Cansev, Mehmet; Guler, Mustafa O; Tekinay, Ayse B
2016-12-01
Parkinson's disease (PD) is characterized by progressive degeneration of dopaminergic nigrostriatal neurons and reduction in striatal dopamine levels. Although there are few treatment options for PD such as Levodopa, they are used just to relieve and modify the symptoms. There are no therapies available for PD to slow down the degeneration process in the brain and recover the lost function. In this study, we used extracellular matrix (ECM) mimetic peptide amphiphile (PA) nanofibers as a potential therapeutic approach in a PD rat model. We demonstrated the effect of heparan sulfate mimetic and laminin mimetic PA nanofibers on reducing striatal injury and enhancing functional recovery after unilateral striatal injection of 6-hydroxydopamine (6-OHDA). The bioactive self-assembled PA nanofibers significantly reduced forelimb asymmetry, contralateral forelimb akinesia and d-amphetamine-induced rotational behavior in cylinder, stepping and rotation tests, respectively, in 6-OHDA-lesioned rats after 6 weeks. The behavioral improvement with PA nanofiber administration was associated with enhanced striatal dopamine and tyrosine hydroxylase content as well as reduced cleaved-Caspase-3 levels. Histological assessment also showed that PA nanofiber injection to the striatum resulted in better tissue integrity compared to control groups. In addition, PA nanofibers reduced the progressive cell loss in SH-SY5Y cells caused by 6-OHDA treatment. These data showed that the bioactive peptide nanofibers improve neurochemical and behavioral consequences of Parkinsonism in rats and provide a promising new strategy for treatment of PD. Biomimetic nanomaterials bearing natural bioactive signals which are derived from extracellular matrix components like laminin and heparan sulfates provide promising therapeutic strategies for regeneration of the nervous system. However, no research has been reported exploring the use of biomimetic materials against degeneration in Parkinson's disease. In this work, we investigated potential therapeutic effects of heparan sulfate and laminin mimetic PA nanofibers on reduction of striatal injury in experimental Parkinson's disease model. PA nanofibers enhanced functional recovery associated with enhanced striatal dopamine and tyrosine hydroxylase content as well as reduced cleaved-Caspase-3 levels. Overall, this study shows the improvement in consequences of Parkinsonism in rats and provides a new platform for treatment of Parkinson's disease. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Functional analysis of corin protein domains required for PCSK6-mediated activation.
Chen, Shenghan; Wang, Hao; Li, Heng; Zhang, Yue; Wu, Qingyu
2018-01-01
Atrial natriuretic peptide (ANP) is a cardiac hormone essential for normal blood pressure and cardiac function. Corin is a transmembrane serine protease that activates ANP. Recently, we identified proprotein convertase subtilisin/kexin-6 (PCSK6), also called PACE4, as the long-sought corin activator. Both corin and PCSK6 are expressed in cardiomyocytes, but corin activation occurs only on the cell surface. It remains unknown if cell membrane association is needed for PCSK6 to activate corin. Here we expressed corin deletion mutants in HEK293 cells to analyze the domain structures required for PCSK6-mediated activation. Our results show that soluble corin lacking the transmembrane domain was activated by PCSK6 in the conditioned medium but not intracellularly. Recombinant PCSK6 also activated the soluble corin under cell-free conditions. Moreover, PCSK6-mediated corin activation was not enhanced by cell membrane fractions. These results indicate that cell membrane association is unnecessary for PCSK6 to activate corin. Experiments with monensin that blocks PCSK6 secretion and immunostaining indicated that the soluble corin and PCSK6 were secreted via different intracellular pathways, which may explain the lack of corin activation inside the cell. We also found that the protein domains in the corin pro-peptide region were dispensable for PCSK6-mediated activation and that addition of heparan sulfate and chondroitin sulfate or treatment with heparinase or chondroitinase did not alter corin activation by PCSK6 in HEK293 cells. Together, our results provide important insights into the molecular and cellular mechanisms underlying PCSK6-mediated corin activation that is critical for cardiovascular homeostasis. Copyright © 2017 Elsevier Ltd. All rights reserved.
Ruma, I Made Winarsa; Putranto, Endy Widya; Kondo, Eisaku; Murata, Hitoshi; Watanabe, Masami; Huang, Peng; Kinoshita, Rie; Futami, Junichiro; Inoue, Yusuke; Yamauchi, Akira; Sumardika, I Wayan; Youyi, Chen; Yamamoto, Ken-Ichi; Nasu, Yasutomo; Nishibori, Masahiro; Hibino, Toshihiko; Sakaguchi, Masakiyo
2016-08-01
The dynamic interaction between tumor cells and their microenvironment induces a proinflammatory milieu that drives cancer development and progression. The S100A8/A9 complex has been implicated in chronic inflammation, tumor development, and progression. The cancer microenvironment contributes to the up-regulation of this protein complex in many invasive tumors, which is associated with the formation of pre-metastatic niches and poor prognosis. Changing adhesive preference of cancer cells is at the core of the metastatic process that governs the reciprocal interactions of cancer cells with the extracellular matrices and neighboring stromal cells. Cell adhesion molecules (CAMs) have been confirmed to have high-level expression in various highly invasive tumors. The expression and function of CAMs are profoundly influenced by the extracellular milieu. S100A8/A9 mediates its effects by binding to cell surface receptors, such as heparan sulfate, TLR4 and RAGE on immune and tumor cells. RAGE has recently been identified as an adhesion molecule and has considerably high identity and similarity to ALCAM and MCAM, which are frequently over-expressed on metastatic malignant melanoma cells. In this study, we demonstrated that ALCAM and MCAM also function as S100A8/A9 receptors as does RAGE and induce malignant melanoma progression by NF-κB activation and ROS formation. Notably, MCAM not only activated NF-κB more prominently than ALCAM and RAGE did but also mediated intracellular signaling for the formation of lung metastasis. MCAM is known to be involved in malignant melanoma development and progression through several mechanisms. Therefore, MCAM is a potential effective target in malignant melanoma treatment.
Jones, Kathryn S; Petrow-Sadowski, Cari; Huang, Ying K; Bertolette, Daniel C; Ruscetti, Francis W
2008-04-01
Cell-free human T-lymphotropic virus type 1 (HTLV-1) virions are poorly infectious in vitro for their primary target cells, CD4(+) T cells. Here, we show that HTLV-1 can efficiently infect myeloid and plasmacytoid dendritic cells (DCs). Moreover, DCs exposed to HTLV-1, both before and after being productively infected, can rapidly, efficiently and reproducibly transfer virus to autologous primary CD4(+) T cells. This DC-mediated transfer of HTLV-1 involves heparan sulfate proteoglycans and neuropilin-1 and results in long-term productive infection and interleukin-2-independent transformation of the CD4(+) T cells. These studies, along with observations of HTLV-1-infected DCs in the peripheral blood of infected individuals, indicate that DCs have a central role in HTLV-1 transmission, dissemination and persistence in vivo. In addition to altering the current paradigm concerning how HTLV-1 transmission occurs, these studies suggest that impairment of DC function after HTLV-1 infection plays a part in pathogenesis.
Pakula, Rachel; Melchior, Aurélie; Denys, Agnès; Vanpouille, Christophe; Mazurier, Joël; Allain, Fabrice
2007-05-01
Many of the biological functions attributed to cell surface proteoglycans are dependent on the interaction with extracellular mediators through their heparan sulphate (HS) moieties and the participation of their core proteins in signaling events. A class of recently identified inflammatory mediators is secreted cyclophilins, which are mostly known as cyclosporin A-binding proteins. We previously demonstrated that cyclophilin B (CyPB) triggers chemotaxis and integrin-mediated adhesion of T lymphocytes mainly of the CD4+/CD45RO+ phenotype. These activities are related to interactions with two types of binding sites, CD147 and cell surface HS. Here, we demonstrate that CyPB-mediated adhesion of CD4+/CD45RO+ T cells is related to p44/42 mitogen-activated protein kinase (MAPK) activation by a mechanism involving CD147 and HS proteoglycans (HSPG). Although HSPG core proteins are represented by syndecan-1, -2, -4, CD44v3 and betaglycan in CD4+/CD45RO+ T cells, we found that only syndecan-1 is physically associated with CD147. The intensity of the heterocomplex increased in response to CyPB, suggesting a transient enhancement and/or stabilization in the association of CD147 to syndecan-1. Pretreatment with anti-syndecan-1 antibodies or knockdown of syndecan-1 expression by RNA interference dramatically reduced CyPB-induced p44/p42 MAPK activation and consequent migration and adhesion, supporting the model in which syndecan-1 serves as a binding subunit to form the fully active receptor of CyPB. Altogether, our findings provide a novel example of a soluble mediator in which a member of the syndecan family plays a critical role in efficient interaction with signaling receptors and initiation of cellular responses.
Li, Nan; Fu, Haiying; Hewitt, Stephen M.; Dimitrov, Dimiter S.
2017-01-01
Neuroblastoma is a childhood cancer that is fatal in almost half of patients despite intense multimodality treatment. This cancer is derived from neuroendocrine tissue located in the sympathetic nervous system. Glypican-2 (GPC2) is a cell surface heparan sulfate proteoglycan that is important for neuronal cell adhesion and neurite outgrowth. In this study, we find that GPC2 protein is highly expressed in about half of neuroblastoma cases and that high GPC2 expression correlates with poor overall survival compared with patients with low GPC2 expression. We demonstrate that silencing of GPC2 by CRISPR-Cas9 or siRNA results in the inhibition of neuroblastoma tumor cell growth. GPC2 silencing inactivates Wnt/β-catenin signaling and reduces the expression of the target gene N-Myc, an oncogenic driver of neuroblastoma tumorigenesis. We have isolated human single-domain antibodies specific for GPC2 by phage display technology and found that the single-domain antibodies can inhibit active β-catenin signaling by disrupting the interaction of GPC2 and Wnt3a. To explore GPC2 as a potential target in neuroblastoma, we have developed two forms of antibody therapeutics, immunotoxins and chimeric antigen receptor (CAR) T cells. Immunotoxin treatment was demonstrated to inhibit neuroblastoma growth in mice. CAR T cells targeting GPC2 eliminated tumors in a disseminated neuroblastoma mouse model where tumor metastasis had spread to multiple clinically relevant sites, including spine, skull, legs, and pelvis. This study suggests GPC2 as a promising therapeutic target in neuroblastoma. PMID:28739923
Li, Nan; Fu, Haiying; Hewitt, Stephen M; Dimitrov, Dimiter S; Ho, Mitchell
2017-08-08
Neuroblastoma is a childhood cancer that is fatal in almost half of patients despite intense multimodality treatment. This cancer is derived from neuroendocrine tissue located in the sympathetic nervous system. Glypican-2 (GPC2) is a cell surface heparan sulfate proteoglycan that is important for neuronal cell adhesion and neurite outgrowth. In this study, we find that GPC2 protein is highly expressed in about half of neuroblastoma cases and that high GPC2 expression correlates with poor overall survival compared with patients with low GPC2 expression. We demonstrate that silencing of GPC2 by CRISPR-Cas9 or siRNA results in the inhibition of neuroblastoma tumor cell growth. GPC2 silencing inactivates Wnt/β-catenin signaling and reduces the expression of the target gene N-Myc, an oncogenic driver of neuroblastoma tumorigenesis. We have isolated human single-domain antibodies specific for GPC2 by phage display technology and found that the single-domain antibodies can inhibit active β-catenin signaling by disrupting the interaction of GPC2 and Wnt3a. To explore GPC2 as a potential target in neuroblastoma, we have developed two forms of antibody therapeutics, immunotoxins and chimeric antigen receptor (CAR) T cells. Immunotoxin treatment was demonstrated to inhibit neuroblastoma growth in mice. CAR T cells targeting GPC2 eliminated tumors in a disseminated neuroblastoma mouse model where tumor metastasis had spread to multiple clinically relevant sites, including spine, skull, legs, and pelvis. This study suggests GPC2 as a promising therapeutic target in neuroblastoma.
Presta, Marco; Oreste, Pasqua; Zoppetti, Giorgio; Belleri, Mirella; Tanghetti, Elena; Leali, Daria; Urbinati, Chiara; Bugatti, Antonella; Ronca, Roberto; Nicoli, Stefania; Moroni, Emanuela; Stabile, Helena; Camozzi, Maura; Hernandez, German Andrés; Mitola, Stefania; Dell'Era, Patrizia; Rusnati, Marco; Ribatti, Domenico
2005-01-01
Low-molecular-weight heparin (LMWH) exerts antitumor activity in clinical trials. The K5 polysaccharide from Escherichia coli has the same structure as the heparin precursor. Chemical and enzymatic modifications of K5 polysaccharide lead to the production of biotechnological heparin-like compounds. We investigated the fibroblast growth factor-2 (FGF2) antagonist and antiangiogenic activity of a series of LMW N,O-sulfated K5 derivatives. Surface plasmon resonance analysis showed that LMW-K5 derivatives bind FGF2, thus inhibiting its interaction with heparin immobilized to a BIAcore sensor chip. Interaction of FGF2 with tyrosine-kinase receptors (FGFRs), heparan sulfate proteoglycans (HSPGs), and alpha(v)beta3 integrin is required for biological response in endothelial cells. Similar to LMWH, LMW-K5 derivatives abrogate the formation of HSPG/FGF2/FGFR ternary complexes by preventing FGF2-mediated attachment of FGFR1-overexpressing cells to HSPG-bearing cells and inhibit FGF2-mediated endothelial cell proliferation. However, LMW-K5 derivatives, but not LMWH, also inhibit FGF2/alpha(v)beta3 integrin interaction and consequent FGF2-mediated endothelial cell sprouting in vitro and angiogenesis in vivo in the chick embryo chorioallantoic membrane. LMW N,O-sulfated K5 derivatives affect both HSPG/FGF2/FGFR and FGF2/alpha(v)beta3 interactions and are endowed with FGF2 antagonist and antiangiogenic activity. These compounds may provide the basis for the design of novel LMW heparin-like angiostatic compounds.
Yamashita, Yuri; Nakada, Satoshi; Yoshihara, Toshinori; Nara, Takeshi; Furuya, Norihiko; Miida, Takashi; Hattori, Nobutaka; Arikawa-Hirasawa, Eri
2018-05-17
Perlecan (HSPG2), a heparan sulfate proteoglycan, is a component of basement membranes and participates in a variety of biological activities. Here, we show physiological roles of perlecan in both obesity and the onset of metabolic syndrome. The perinatal lethality-rescued perlecan knockout (Hspg2 -/- -Tg) mice showed a smaller mass and cell size of white adipose tissues than control (WT-Tg) mice. Abnormal lipid deposition, such as fatty liver, was not detected in the Hspg2 -/- -Tg mice, and those mice also consumed more fat as an energy source, likely due to their activated fatty acid oxidation. In addition, the Hspg2 -/- -Tg mice demonstrated increased insulin sensitivity. Molecular analysis revealed the significantly relatively increased amount of the muscle fiber type IIA (X) isoform and a larger quantity of mitochondria in the skeletal muscle of Hspg2 -/- -Tg mice. Furthermore, the perlecan-deficient skeletal muscle also had elevated levels of peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC1α) protein. PGC1α expression is activated by exercise, and induces mitochondrial biosynthesis. Thus, perlecan may act as a mechano-regulator of catabolism of both lipids and glucose by shifting the muscle fiber composition to oxidative fibers. Our data suggest that downregulation of perlecan is a promising strategy to control metabolic syndrome.
Genetic analysis of the heparan modification network in Caenorhabditis elegans.
Townley, Robert A; Bülow, Hannes E
2011-05-13
Heparan sulfates (HS) are highly modified sugar polymers in multicellular organisms that function in cell adhesion and cellular responses to protein signaling. Functionally distinct, cell type-dependent HS modification patterns arise as the result of a conserved network of enzymes that catalyze deacetylations, sulfations, and epimerizations in specific positions of the sugar residues. To understand the genetic interactions of the enzymes during the HS modification process, we have measured the composition of HS purified from mutant strains of Caenorhabditis elegans. From these measurements we have developed a genetic network model of HS modification. We find the interactions to be highly recursive positive feed-forward and negative feedback loops. Our genetic analyses show that the HS C-5 epimerase hse-5, the HS 2-O-sulfotransferase hst-2, or the HS 6-O-sulfotransferase hst-6 inhibit N-sulfation. In contrast, hse-5 stimulates both 2-O- and 6-O-sulfation and, hst-2 and hst-6 inhibit 6-O- and 2-O-sulfation, respectively. The effects of hst-2 and hst-6 on N-sulfation, 6-O-sulfation, and 2-O-sulfation appear largely dependent on hse-5 function. This core of regulatory interactions is further modulated by 6-O-endosulfatase activity (sul-1). 47% of all 6-O-sulfates get removed from HS and this editing process is dependent on hst-2, thereby providing additional negative feedback between 2-O- and 6-O-sulfation. These findings suggest that the modification patterns are highly sensitive to the relative composition of the HS modification enzymes. Our comprehensive genetic analysis forms the basis of understanding the HS modification network in metazoans.
Tecle, Eillen; Diaz-Balzac, Carlos A.; Bülow, Hannes E.
2013-01-01
Heparan sulfate (HS) is an unbranched glycosaminoglycan exhibiting substantial molecular diversity due to multiple, nonuniformly introduced modifications, including sulfations, epimerization, and acetylation. HS modifications serve specific and instructive roles in neuronal development, leading to the hypothesis of a HS code that regulates nervous system patterning. Although the in vivo roles of many of the HS modifications have been investigated, very little is known about the function of HS 3-O-sulfation in vivo. By examining patterning of the Caenorhabditis elegans nervous system in loss of function mutants of the two 3-O-sulfotransferases, hst-3.1 and hst-3.2, we found HS 3-O-sulfation to be largely dispensable for overall neural development. However, generation of stereotypical neurite branches in hermaphroditic-specific neurons required hst-3.1, hst-3.2, as well as an extracellular cell adhesion molecule encoded by kal-1, the homolog of Kallmann Syndrome associated gene 1/anosmin-1. In contrast, kal-1−dependent neurite branching in AIY neurons required catalytic activity of hst-3.2 but not hst-3.1. The context-dependent requirement for hst-3.2 and hst-3.1 indicates that both enzymes generate distinct types of HS modification patterns in different cell types, which regulate kal-1 to promote neurite branching. We conclude that HS 3-O-sulfation does not play a general role in establishing the HS code in C. elegans but rather plays a specialized role in a context-dependent manner to establish defined aspects of neuronal circuits. PMID:23451335
Ryazantsev, Sergey; Yu, Wei-Hong; Zhao, Hui-Zhi; Neufeld, Elizabeth F.; Ohmi, Kazuhiro
2007-01-01
The neurodegenerative disease MPS III B (Sanfilippo syndrome type B) is caused by mutations in the gene encoding the lysosomal enzyme α-N-acetylglucosaminidase, with a resulting block in heparan sulfate degradation. A mouse model with disruption of the Naglu gene allows detailed study of brain pathology. In contrast to somatic cells, which accumulate primarily heparan sulfate, neurons accumulate a number of apparently unrelated metabolites, including subunit c of mitochondrial ATP synthase (SCMAS). SCMAS accumulated from 1 month of age, primarily in the medial entorhinal cortex and layer V of the somatosensory cortex. Its accumulation was not due to the absence of specific proteases. Light microscopy of brain sections of 6 months-old mice showed SCMAS to accumulate in the same areas as glycosaminoglycan and unesterified cholesterol, in the same cells as ubiquitin and GM3 ganglioside, and in the same organelles as Lamp 1 and Lamp 2. Cryo-immuno electron microscopy showed SCMAS to be present in Lamp positive vesicles bounded by a single membrane (lysosomes), in fingerprint-like layered arrays. GM3 ganglioside was found in the same lysosomes, but was not associated with the SCMAS arrays. GM3 ganglioside was also seen in lysosomes of microglia, suggesting phagocytosis of neuronal membranes. Samples used for cryo-EM and further processed by standard EM procedures (osmium tetroxide fixation and plastic embedding) showed the disappearance of the SCMAS fingerprint arrays and appearance in the same location of “zebra bodies”, well known but little understood inclusions in the brain of patients with mucopolysaccharidoses. PMID:17185018
Dong, Li-Qun; Wang, Zheng; Yu, Ping; Guo, Yan-Nan; Wu, Jin; Feng, Shi-Pin; Li, Sha
2009-01-01
To investigate the expression of glomerular heparin sulfate (HS) in paediatric patients with minimal change nephritic syndrome (MCNS). The kidyney tissues were collected by biopsy from 13 paediatric patients with MCNS, while 5 normal renal biopsy samples were used as control. HS in glomeruli was analysed by indirect immunofluorescence staining using four different monoclonal antibodies, Hepss1, 3G10, JM403 and 10E4, which all recognize distinct HS species and each interacts with a specific HS domain. The concentrations of urine heparan sulfate also were measured by enzyme-linked immunosorbent assay (Elisa). Expression of HS fine domains was aberrant in paediatric patients compared with control subjects. Children with MCNS in replase showed a decreased glomerular expression of 10E4, JM403 and Hepss1 (P < 0.05). The level of urinary HS was significantly increased in peadiatric patients with MCNS when compared with that in control subjects (P < 0.01). These results suggest that loss of heparan sulphate in renal tissue may play a role in the pathogenesis of MCNS proteinuria.
Mast Cells Produce a Unique Chondroitin Sulfate Epitope.
Farrugia, Brooke L; Whitelock, John M; O'Grady, Robert; Caterson, Bruce; Lord, Megan S
2016-02-01
The granules of mast cells contain a myriad of mediators that are stored and protected by the sulfated glycosaminoglycan (GAG) chains that decorate proteoglycans. Whereas heparin is the GAG predominantly associated with mast cells, mast cell proteoglycans are also decorated with heparan sulfate and chondroitin sulfate (CS). This study investigated a unique CS structure produced by mast cells that was detected with the antibody clone 2B6 in the absence of chondroitinase ABC digestion. Mast cells in rodent tissue sections were characterized using toluidine blue, Leder stain and the presence of mast cell tryptase. The novel CS epitope was identified in rodent tissue sections and localized to cells that were morphologically similar to cells chemically identified as mast cells. The rodent mast cell-like line RBL-2H3 was also shown to express the novel CS epitope. This epitope co-localized with multiple CS proteoglycans in both rodent tissue and RBL-2H3 cultured cells. These findings suggest that the novel CS epitope that decorates mast cell proteoglycans may play a role in the way these chains are structured in mast cells. © 2016 The Histochemical Society.
Alves, Christina S.; Konstantopoulos, Konstantinos
2012-01-01
Fibrin(ogen) mediates sustained tumor cell adhesion and survival in the pulmonary vasculature, thereby facilitating the metastatic dissemination of tumor cells. CD44 is the major functional fibrin receptor on colon carcinoma cells. Growth factors, such as platelet-derived growth factor (PDGF), induce post-translational protein modifications, which modulate ligand binding activity. In view of the roles of PDGF, fibrin(ogen) and CD44 in cancer metastasis, we aimed to delineate the effect of PDGF on CD44-fibrin recognition. By immunoprecipitating CD44 from PDGF-treated and untreated LS174T colon carcinoma cells, which express primarily CD44v, we demonstrate that PDGF enhances the adhesion of CD44v-coated beads to immobilized fibrin. Enzymatic inhibition studies coupled with flow-based adhesion assays and autoradiography reveal that PDGF augments the binding of CD44v to fibrin by significantly attenuating the extent of CD44 sulfation primarily on chondroitin and dermatan sulfate chains. Surface plasmon resonance assays confirm that PDGF enhances the affinity of CD44v-fibrin binding by markedly reducing its dissociation rate while modestly increasing the association rate. PDGF mildly reduces the affinity of CD44v-hyaluronan binding without affecting selectin-CD44v recognition. The latter is attributed to the fact that CD44v binds to selectins via sialofucosylated O-linked residues independent of heparan, dermatan and chondroitin sulfates. Interestingly, PDGF moderately reduces the sulfation of CD44s and CD44s-fibrin recognition. Collectively, these data offer a novel perspective into the mechanism by which PGDF regulates CD44-dependent binding of metastatic colon carcinoma cells to fibrin(ogen). PMID:23056168
Nazli, Aisha; Dizzell, Sara; Zahoor, Muhammad Atif; Ferreira, Victor H; Kafka, Jessica; Woods, Matthew William; Ouellet, Michel; Ashkar, Ali A; Tremblay, Michel J; Bowdish, Dawn Me; Kaushic, Charu
2018-03-19
More than 40% of HIV infections occur via female reproductive tract (FRT) through heterosexual transmission. Epithelial cells that line the female genital mucosa are the first line of defense against HIV-1 and other sexually transmitted pathogens. These sentient cells recognize and respond to external stimuli by induction of a range of carefully balanced innate immune responses. Previously, we have shown that in response to HIV-1 gp120, the genital epithelial cells (GECs) from upper reproductive tract induce an inflammatory response that may facilitate HIV-1 translocation and infection. In this study, we report that the endometrial and endocervical GECs simultaneously induce biologically active interferon-β (IFNβ) antiviral responses following exposure to HIV-1 that act to protect the epithelial tight junction barrier. The innate antiviral response was directly induced by HIV-1 envelope glycoprotein gp120 and addition of gp120 neutralizing antibody inhibited IFNβ production. Interferon-β was induced by gp120 in upper GECs through Toll-like receptor 2 signaling and required presence of heparan sulfate on epithelial cell surface. The induction of IFNβ was dependent upon activation of transcription factor IRF3 (interferon regulatory factor 3). The IFNβ was biologically active, had a protective effect on epithelial tight junction barrier and was able to inhibit HIV-1 infection in TZM-bl indicator cells and HIV-1 replication in T cells. This is the first report that recognition of HIV-1 by upper GECs leads to induction of innate antiviral pathways. This could explain the overall low infectivity of HIV-1 in the FRT and could be exploited for HIV-1 prophylaxis.Cellular and Molecular Immunology advance online publication, 19 March 2018; doi:10.1038/cmi.2017.168.
Zhu, Huanhuan; Le, Wenjun; Cui, Shaobin; Chen, Xin; Li, Wei; Zhang, Fulei; Huang, Yong; Sh, Donglu; Cui, Zheng; Shao, Chengwei; Chen, Bingdi
2018-01-01
Introduction Pancreatic cancer (PC) has a poor prognosis with high mortality, due to the lack of effective early diagnostic and prognostic tools. Materials and methods In order to target and diagnose PC, we developed a dual-modal imaging probe using Glypican-1 (GPC-1) antibody conjugated with Gd–Au nanoclusters (NCs; Gd-Au-NC-GPC-1). GPC-1 is a type of cell surface heparan sulfate proteoglycan, which is often highly expressed in PC. The probe was successfully prepared with a hydrodynamic diameter ranging from 13.5 to 24.4 nm. Results Spectral characteristics showed absorption at 280 nm and prominent emission at 650 nm. Confocal microscopic imaging showed effective detection of GPC-1 highly expressed PC cells by Gd-Au-NC-GPC-1, which was consistent with flow cytometry results. In vitro relaxivity characterization demonstrated that the r1 value of the probe was 17.722 s−1 mM−1 Gd, which was almost 4 times higher compared with that of Gd-diethylenetriaminepentacetate (DTPA; r1 value =4.6 s−1 mM−1 Gd). Gd-Au-NC-GPC-1 exhibited similar magnetic resonance (MR) signals when compared to Gd-DTPA even at lower Gd concentrations. Much higher MR signals were registered in PC cells (COLO-357) compared with normal cells (293T). Furthermore, Gd-Au-NC-GPC-1 could effectively detect PC cells in vivo by dual-modal fluorescence imaging/magnetic resonance imaging (FI/MRI) at 30 minutes postinjection. In addition, Gd-Au-NC-GPC-1 did not show significant biotoxicity to normal cells at tested concentrations both in vitro and in vivo. Conclusion Gd-Au-NC-GPC-1 has demonstrated to be a promising dual-modal FI/MRI contrast agent for targeted diagnosis of PC. PMID:29750031
Huang, Xin; Fan, Chengqi; Zhu, Huanhuan; Le, Wenjun; Cui, Shaobin; Chen, Xin; Li, Wei; Zhang, Fulei; Huang, Yong; Sh, Donglu; Cui, Zheng; Shao, Chengwei; Chen, Bingdi
2018-01-01
Pancreatic cancer (PC) has a poor prognosis with high mortality, due to the lack of effective early diagnostic and prognostic tools. In order to target and diagnose PC, we developed a dual-modal imaging probe using Glypican-1 (GPC-1) antibody conjugated with Gd-Au nanoclusters (NCs; Gd-Au-NC-GPC-1). GPC-1 is a type of cell surface heparan sulfate proteoglycan, which is often highly expressed in PC. The probe was successfully prepared with a hydrodynamic diameter ranging from 13.5 to 24.4 nm. Spectral characteristics showed absorption at 280 nm and prominent emission at 650 nm. Confocal microscopic imaging showed effective detection of GPC-1 highly expressed PC cells by Gd-Au-NC-GPC-1, which was consistent with flow cytometry results. In vitro relaxivity characterization demonstrated that the r1 value of the probe was 17.722 s -1 mM -1 Gd, which was almost 4 times higher compared with that of Gd-diethylenetriaminepentacetate (DTPA; r1 value =4.6 s -1 mM -1 Gd). Gd-Au-NC-GPC-1 exhibited similar magnetic resonance (MR) signals when compared to Gd-DTPA even at lower Gd concentrations. Much higher MR signals were registered in PC cells (COLO-357) compared with normal cells (293T). Furthermore, Gd-Au-NC-GPC-1 could effectively detect PC cells in vivo by dual-modal fluorescence imaging/magnetic resonance imaging (FI/MRI) at 30 minutes postinjection. In addition, Gd-Au-NC-GPC-1 did not show significant biotoxicity to normal cells at tested concentrations both in vitro and in vivo. Gd-Au-NC-GPC-1 has demonstrated to be a promising dual-modal FI/MRI contrast agent for targeted diagnosis of PC.
Huang, Yu; Mao, Yang; Buczek-Thomas, Jo Ann; Nugent, Matthew A.; Zaia, Joseph
2014-01-01
Sulfs are extracellular endosulfatases that selectively remove the 6-O-sulfate groups from cell surface heparan sulfate (HS) chain. By altering the sulfation at these particular sites, Sulfs function to remodel HS chains. As a result of the remodeling activity, HSulf2 regulates a multitude of cell-signaling events that depend on interactions between proteins and HS. Previous efforts to characterize the substrate specificity of human Sulfs (HSulfs) focused on the analysis of HS disaccharides and synthetic repeating units. In this study, we characterized the substrate preferences of human HSulf2 using HS oligosaccharides with various lengths and sulfation degrees from several naturally occurring HS sources by applying liquid chromatography mass spectrometry based glycomics methods. The results showed that HSulf2 preferentially digests highly sulfated HS oligosaccharides with zero acetyl groups and this preference is length dependent. In terms of length of oligosaccharides, HSulf2 digestion induced more sulfation decrease on DP6 (DP: degree of polymerization) compared to DP2, DP4 and DP8. In addition, the HSulf2 preferentially digests the oligosaccharide domain located at the non-reducing end (NRE) of the HS and heparin chain. In addition, the HSulf2 digestion products were altered only for specific isomers. HSulf2 treated NRE oligosaccharides also showed greater decrease in cell proliferation than those from internal domains of the HS chain. After further chromatographic separation, we identified the three most preferred unsaturated hexasaccharide for HSulf2. PMID:25127119
Kaji, T; Hiraga, S; Ohkawara, S; Inada, M; Yamamoto, C; Kozuka, H; Koizumi, F
1995-05-01
The alteration of glycosaminoglycans (GAGs) in cultured bovine aortic endothelial cells after exposure to basic fibroblast growth factor (bFGF) was investigated. It was found that the incorporation of [3H]glucosamine into GAGs was markedly increased by bFGF in both the cell layer and the conditioned medium; however, that of [35S]sulfate was not changed by the growth factor. These results indicated that bFGF enhanced the sugar-chain formation but did not affect their sulfation in endothelial GAG production. Similar changes were observed in either bovine aortic smooth-muscle cells and human fibroblastic IMR-90 cells to greater and lesser degrees, respectively. Characterization of GAGs in the endothelial cell layer and the conditioned medium revealed that bFGF enhanced both heparan sulfate and the other GAGs to a similar degree. The present data suggest that bFGF may be involved in the regulation of the blood coagulation system via altering GAGs of the vascular tissue when the endothelium was damaged.
A multiwell format assay for heparanase.
Behzad, Farhad; Brenchley, Paul E C
2003-09-15
This assay employs a biotinylated heparan sulfate glycosaminoglycan (HSGAG) substrate that is covalently linked to the surface of 96-well immunoassay plates. The ratio of biotin:HSGAG and the coating concentration of substrate bound to the wells have been optimized and allow removal of biotin HSGAG within 60 min of incubation at 37 degrees C in assay buffer with a standard dilution of bacterial heparitinase or platelet heparanase. Loss of biotin signal from the well surface is detected on incubation with peroxidase-streptavidin followed by color development using 3,3',5,5'-tetramethylbenzidine as the peroxidase substrate. The new assay allows specific detection of heparanase activity in multiple samples in a total time of 3 h including a 1-h substrate digestion step and is a significant improvement with regard to sensitivity, specificity, and ease of handling of multiple samples compared to other described assays. Heparanase specifically degrades the biotinylated HSGAG substrate, when used with an optimized assay buffer. A range of enzymes including collagenase, trypsin, plasmin, pepsin, chondroitinases, hyaluronidase, and neuraminidase show no effect on the substrate under optimized assay conditions. The covalent linkage of the substrate to the well prevents leaching of substrate and allows preparation and long-term storage of substrate-coated plates. The assay can be used to detect heparanase levels in clinical samples and cell culture supernatants and is ideal as a screening method for antagonists of enzyme activity.
Drosophila Glypicans Regulate Follicle Stem Cell Maintenance and Niche Competition.
Su, Tsu-Yi; Nakato, Eriko; Choi, Pui Yee; Nakato, Hiroshi
2018-04-09
Adult stem cells reside in specialized microenvironments, called niches, which provide signals for stem cells to maintain their undifferentiated and self-renewing state. To maintain stem cell quality, several types of stem cells are known to be regularly replaced by progenitor cells through niche competition. However, the cellular and molecular bases for stem cell competition for niche occupancy are largely unknown. Here, we show that two Drosophila members of the glypican family of heparan sulfate proteoglycans (HSPGs), Dally and Dally-like (Dlp), differentially regulate follicle stem cell (FSC) maintenance and FSC competitiveness for niche occupancy. Lineage analyses of glypican mutant FSC clones showed that dally is essential for normal FSC maintenance. In contrast, dlp is a hyper-competitive mutation: dlp mutant FSC progenitors often eventually occupy the entire epithelial sheet. RNAi knockdown experiments showed that Dally and Dlp play both partially redundant and distinct roles in regulating Jak/Stat, Wg and Hh signaling in FSCs. The Drosophila FSC system offers a powerful genetic model to study the mechanisms by which HSPGs exert specific functions in stem cell replacement and competition. Copyright © 2018, Genetics.
Nasser, Nicola J.; Avivi, Aaron; Shafat, Itay; Edovitsky, Evgeny; Zcharia, Eyal; Ilan, Neta; Vlodavsky, Israel; Nevo, Eviatar
2009-01-01
Heparanase is an endoglycosidase that degrades heparan sulfate (HS) at the cell surface and in the extracellular matrix. Heparanase is expressed mainly by cancer cells, and its expression is correlated with increased tumor aggressiveness, metastasis, and angiogenesis. Here, we report the cloning of a unique splice variant (splice 36) of heparanase from the subterranean blind mole rat (Spalax). This splice variant results from skipping part of exon 3, exons 4 and 5, and part of exon 6 and functions as a dominant negative to the wild-type enzyme. It inhibits HS degradation, suppresses glioma tumor growth, and decreases experimental B16–BL6 lung colonization in a mouse model. Intriguingly, Spalax splice variant 7 of heparanase (which results from skipping of exon 7) is devoid of enzymatic activity, but unlike splice 36 it enhances tumor growth. Our results demonstrate that alternative splicing of heparanase regulates its enzymatic activity and might adapt the heparanase function to the fluctuating normoxic–hypoxic subterranean environment that Spalax experiences. Development of anticancer drugs designed to suppress tumor growth, angiogenesis, and metastasis is a major challenge, of which heparanase inhibition is a promising approach. We anticipate that the heparanase splicing model, evolved during 40 million years of Spalacid adaptation to underground life, would pave the way for the development of heparanase-based therapeutic modalities directed against angiogenesis, tumor growth, and metastasis. PMID:19164514
Macrophage polarization alters the expression and sulfation pattern of glycosaminoglycans.
Martinez, Pierre; Denys, Agnès; Delos, Maxime; Sikora, Anne-Sophie; Carpentier, Mathieu; Julien, Sylvain; Pestel, Joël; Allain, Fabrice
2015-05-01
Macrophages are major cells of inflammatory process and take part in a large number of physiological and pathological processes. According to tissue environment, they can polarize into pro-inflammatory (M1) or alternative (M2) cells. Although many evidences have hinted to a potential role of cell-surface glycosaminoglycans (GAGs) in the functions of macrophages, the effect of M1 or M2 polarization on the biosynthesis of these polysaccharides has not been investigated so far. GAGs are composed of repeat sulfated disaccharide units. Heparan (HS) and chondroitin/dermatan sulfates (CS/DS) are the major GAGs expressed at the cell membrane. They are involved in numerous biological processes, which rely on their ability to selectively interact with a large panel of proteins. More than 20 genes encoding sulfotransferases have been implicated in HS and CS/DS biosynthesis, and the functional repertoire of HS and CS/DS has been related to the expression of these isoenzymes. In this study, we analyzed the expression of sulfotransferases as a response to macrophage polarization. We found that M1 and M2 activation drastically modified the profiles of expression of numerous HS and CS/DS sulfotransferases. This was accompanied by the expression of GAGs with distinct structural features. We then demonstrated that GAGs of M2 macrophages were efficient to present fibroblast growth factor-2 in an assay of tumor cell proliferation, thus indicating that changes in GAG structure may contribute to the functions of polarized macrophages. Altogether, our findings suggest a regulatory mechanism in which fine modifications in GAG biosynthesis may participate to the plasticity of macrophage functions. © The Author 2014. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Hayashi, Kazuhiro; Mochizuki, Mayumi; Nomizu, Motoyoshi; Uchinuma, Eijyu; Yamashina, Shohei; Kadoya, Yuichi
2002-04-01
We established a serum-free organ culture system of isolated single vibrissa rudiments taken from embryonic day 13 mice. This system allowed us to test more than 30 laminin-derived cell adhesive peptides to determine their roles on the growth and differentiation of vibrissa hair follicles. We found that the RKRLQVQLSIRT sequence (designated AG-73), which mapped to the LG-4 module of the laminin-alpha1 chain carboxyl-terminal G domain, perturbed the growth of hair follicles in vitro. AG-73 is one of the cell-binding peptides identified from more than 600 systematically synthesized 12 amino acid peptides covering the whole amino acid sequence of the laminin-alpha1, -beta1, and -gamma1 chains, by cell adhesion assay. Other cell-adhesive laminin peptides and a control scrambled peptide, LQQRRSVLRTKI, however, failed to show any significant effects on the growth of hair follicles. The AG-73 peptide binds to syndecan-1, a transmembrane heparan-sulfate proteoglycan. Syndecan-1 was expressed in both the mesenchymal condensation and the epithelial hair peg of developing vibrissa, suggesting that AG-73 binding to the cell surface syndecan-1 perturbed the epithelial-mesenchymal interactions of developing vibrissa. The formation of hair bulbs was aberrant in the explants treated with AG-73. In addition, impaired basement membrane formation, an abnormal cytoplasmic bleb formation, and an unusual basal formation of actin bundles were noted in the AG-73-treated-hair matrix epithelium, indicating that AG-73 binding perturbs various steps of epithelial morphogenesis, including the basement membrane remodeling. We also found a region-specific loss of the laminin-alpha1 chain in the basement membrane at the distal region of the invading hair follicle epithelium, indicating that laminins play a part in hair morphogenesis.
Wang, Chia-Hui; Liu, Jyung-Hurng; Lee, Shao-Chen; Hsiao, Chwan-Deng; Wu, Wen-Guey
2006-01-06
Cobra cardiotoxins, a family of basic polypeptides having lipid- and heparin-binding capacities similar to the cell-penetrating peptides, induce severe tissue necrosis and systolic heart arrest in snakebite victims. Whereas cardiotoxins are specifically retained on the cell surface via heparan sulfate-mediated processes, their lipid binding ability appears to be responsible, at least in part, for cardiotoxin-induced membrane leakage and cell death. Although the exact role of lipids involved in toxin-mediated cytotoxicity remains largely unknown, monoclonal anti-sulfatide antibody O4 has recently been shown to inhibit the action of CTX A3, the major cardiotoxin from Taiwan cobra venom, on cardiomyocytes by preventing cardiotoxin-induced membrane leakage and CTX A3 internalization into mitochondria. Here, we show that anti-sulfatide acts by blocking the binding of CTX A3 to the sulfatides in the plasma membrane to prevent sulfatide-dependent CTX A3 membrane pore formation and internalization. We also describe the crystal structure of a CTX A3-sulfatide complex in a membrane-like environment at 2.3 angstroms resolution. The unexpected orientation of the sulfatide fatty chains in the structure allows prediction of the mode of toxin insertion into the plasma membrane. CTX A3 recognizes both the headgroup and the ceramide interfacial region of sulfatide to induce a lipid conformational change that may play a key role in CTX A3 oligomerization and cellular internalization. This proposed lipid-mediated toxin translocation mechanism may also shed light on the cellular uptake mechanism of the amphiphilic cell-penetrating peptides known to involve multiple internalization pathways.
Genetic Analysis of the Heparan Modification Network in Caenorhabditis elegans*
Townley, Robert A.; Bülow, Hannes E.
2011-01-01
Heparan sulfates (HS) are highly modified sugar polymers in multicellular organisms that function in cell adhesion and cellular responses to protein signaling. Functionally distinct, cell type-dependent HS modification patterns arise as the result of a conserved network of enzymes that catalyze deacetylations, sulfations, and epimerizations in specific positions of the sugar residues. To understand the genetic interactions of the enzymes during the HS modification process, we have measured the composition of HS purified from mutant strains of Caenorhabditis elegans. From these measurements we have developed a genetic network model of HS modification. We find the interactions to be highly recursive positive feed-forward and negative feedback loops. Our genetic analyses show that the HS C-5 epimerase hse-5, the HS 2-O-sulfotransferase hst-2, or the HS 6-O-sulfotransferase hst-6 inhibit N-sulfation. In contrast, hse-5 stimulates both 2-O- and 6-O-sulfation and, hst-2 and hst-6 inhibit 6-O- and 2-O-sulfation, respectively. The effects of hst-2 and hst-6 on N-sulfation, 6-O-sulfation, and 2-O-sulfation appear largely dependent on hse-5 function. This core of regulatory interactions is further modulated by 6-O-endosulfatase activity (sul-1). 47% of all 6-O-sulfates get removed from HS and this editing process is dependent on hst-2, thereby providing additional negative feedback between 2-O- and 6-O-sulfation. These findings suggest that the modification patterns are highly sensitive to the relative composition of the HS modification enzymes. Our comprehensive genetic analysis forms the basis of understanding the HS modification network in metazoans. PMID:21454666
Yoshitake, Hiroshi; Oda, Risako; Yanagida, Mitsuaki; Kawasaki, Yu; Sakuraba, Mayumi; Takamori, Kenji; Hasegawa, Akiko; Fujiwara, Hiroshi; Araki, Yoshihiko
2016-06-01
We previously established an anti-mouse sperm auto-monoclonal antibody, Ts4, which shows immunoreactivity against several kinds of glycoproteins in the acrosomal region of epididymal spermatozoa, testicular germ cells, and early embryo, via binding to an epitope containing a common N-linked oligosaccharide (OS) chain on the molecules. In mice, we have already demonstrated that the OS chain in the epitope for Ts4 is a fucosylated agalacto-complex-type biantennary glycan carrying bisecting N-acetylglucosamine. In the testis, one of the specific OS chain-conjugated molecules is TEX101, a germ cell-marker glycoprotein, which is expressed in spermatocytes, spermatids, and testicular spermatozoa, but not in epididymal spermatozoa. In this study, we identified a Ts4-reactive glycoprotein in mouse cauda epididymal sperm. An immunoprecipitation method together with liquid chromatography-tandem mass spectrometry showed that alpha-N-acetylglucosaminidase (Naglu; a degradation enzyme of heparan sulfate) is one of the glycoproteins recognized by Ts4 in the epididymal spermatozoa. Western blot and immunohistochemical analyses revealed that mouse Naglu exists in two forms (82 and 77kDa) and is expressed in the acrosomal region and the flagellum of cauda epididymal sperm. Of the two Naglu-forms expressed in sperm, Ts4 immunoreacted against only the 82-kDa form located on the acrosomal region. The Ts4 mAb and anti-Naglu pAb negatively affected mouse fertilization in vitro. In addition, Ts4 inhibited sperm acrosome reaction induced by heparan sulfate. The Ts4-recognized fucosylated agalactobiantennary complex-type glycan with bisecting N-acetylglucosamine and Naglu on cauda epididymal spermatozoa may play a role in the process of fertilization. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Baxter, Melissa A; Wynn, Robert F; Deakin, Jonathan A; Bellantuono, Ilaria; Edington, Kirsten G; Cooper, Alan; Besley, Guy T N; Church, Heather J; Wraith, J Ed; Carr, Trevor F; Fairbairn, Leslie J
2002-03-01
We have investigated the utility of bone marrow-derived mesenchymal stem cells (MSCs) as targets for gene therapy of the autosomal recessive disorder mucopolysaccharidosis type IH (MPS-IH, Hurler syndrome). Cultures of MSCs were initially exposed to a green fluorescent protein-expressing retrovirus. Green fluorescent protein-positive cells maintained their proliferative and differentiation capacity. Next we used a vector encoding alpha-L-iduronidase (IDUA), the enzyme that is defective in MPS-IH. Following transduction, MPS-IH MSCs expressed high levels of IDUA and secreted supernormal levels of this enzyme into the extracellular medium. Exogenous IDUA expression led to a normalization of glycosaminoglycan storage in MPS-IH cells, as evidenced by a dramatic decrease in the amount of (35)SO(4) sequestered within the heparan sulfate and dermatan sulfate compartments of these cells. Finally, gene-modified MSCs were able to cross-correct the enzyme defect in untransduced MPS-IH fibroblasts via protein transfer.
Investigation of viral vectors using atomic force microscopy and microfluidic devices
NASA Astrophysics Data System (ADS)
Negishi, Atsuko
Researchers are modifying viruses into gene delivery vehicles in hope to cure diseases such as muscular dystrophy, hemophilia and cancer. Significant progress has been made toward this end, but further development and success of viral vectors depend on a deeper understanding of viral structure and physiology. Recent advances in microscopy have allowed new approaches to studying viruses that complement existing methodologies. Presented in this dissertation are novel viral studies using the atomic force microscope (AFM), a microscope that provides topographic information at the nanometer scale. As well microfluidic channels were used to study the effect of fluid flow properties on infection. A number of viruses are currently under study as potential vectors. We focus our studies on the adenovirus (Ad) and the adeno-associated virus (AAV) which have numerous attractive properties as vectors. The AFM is used to probe first, the structural aspects of the Ad and second, the virus-receptor interactions between AAV and its cell surface receptor, heparan sulfate proteoglycan (HSPG). The AFM was capable of imaging the capsid facets of intact Ad and DNA strands released from disrupted Ad capsids. In addition, we found that the stability of the capsid depended on the surface chemistry. An AFM-based binding assay was developed to study the binding between AAV and HSPG. The advantage of using the AFM for this purpose is its ability to simultaneously provide structural and quantitative information at the single molecule level. We measured a binding constant of 3.4 +/- 0.3 nM which is consistent with published reports. Microfluidic devices were used to study the dependence of fluid flow on infection. Cells were cultured in microfluidic channels and exposed to AAV vectors at various shear stresses. We found that a lower percentage of the cells were infected at higher shear stress. We also found that fluid forces can indirectly play a role in viral infection by influencing the cell state. A significantly lower percentage of cells that were treated with shear stress prior to vector exposure were infected compared to cells which were not exposed to shear stress.
Agrin is a major heparan sulfate proteoglycan in the human glomerular basement membrane.
Groffen, A J; Ruegg, M A; Dijkman, H; van de Velden, T J; Buskens, C A; van den Born, J; Assmann, K J; Monnens, L A; Veerkamp, J H; van den Heuvel, L P
1998-01-01
Agrin is a heparan sulfate proteoglycan (HSPG) that is highly concentrated in the synaptic basal lamina at the neuromuscular junction (NMJ). Agrin-like immunoreactivity is also detected outside the NMJ. Here we show that agrin is a major HSPG component of the human glomerular basement membrane (GBM). This is in addition to perlecan, a previously characterized HSPG of basement membranes. Antibodies against agrin and against an unidentified GBM HSPG produced a strong staining of the GBM and the NMJ, different from that observed with anti-perlecan antibodies. In addition, anti-agrin antisera recognized purified GBM HSPG and competed with an anti-GBM HSPG monoclonal antibody in ELISA. Furthermore, both antibodies recognized a molecule that migrated in SDS-PAGE as a smear and had a molecular mass of approximately 200-210 kD after deglycosylation. In immunoelectron microscopy, agrin showed a linear distribution along the GBM and was present throughout the width of the GBM. This was again different from perlecan, which was exclusively present on the endothelial side of the GBM and was distributed in a nonlinear manner. Quantitative ELISA showed that, compared with perlecan, the agrin-like GBM HSPG showed a sixfold higher molarity in crude glomerular extract. These results show that agrin is a major component of the GBM, indicating that it may play a role in renal ultrafiltration and cell matrix interaction. (J Histochem Cytochem 46:19-27, 1998)
Pearson, Brandon L; Corley, Michael J; Vasconcellos, Amy; Blanchard, D Caroline; Blanchard, Robert J
2013-04-15
Abnormal cellular growth and organization have been characterized in postmortem tissue from brains of autistic individuals, suggestive of pathology in a critical neurogenic niche, the subventricular zone (SVZ) of the brain lateral ventricles (LV). We examined cellular organization, cell proliferation, and constituents of the extracellular matrix such as N-sulfated heparan sulfate (HS) and laminin (LAM) in postmortem brain tissue from the LV-SVZ of young to elderly individuals with autism (n=4) and age-matched typically developing (TD) individuals (n=4) using immunofluorescence techniques. Strong and systematic reductions in HS immunofluorescence were observed in the LV-SVZ of the TD individuals with increasing age. For young through mature, but not elderly, autistic pair members, HS was reduced compared to their matched TDs. Cellular proliferation (Ki67+) was higher in the autistic individual of the youngest age-matched pair. These preliminary data suggesting that HS may be reduced in young to mature autistic individuals are in agreement with previous findings from the BTBR T+tf/J mouse, an animal model of autism; from mice with genetic modifications reducing HS; and with genetic variants in HS-related genes in autism. They suggest that aberrant extracellular matrix glycosaminoglycan function localized to the subventricular zone of the lateral ventricles may be a biomarker for autism, and potentially involved in the etiology of the disorder. Copyright © 2013 Elsevier B.V. All rights reserved.
Huegel, Julianne; Mundy, Christina; Sgariglia, Federica; Nygren, Patrik; Billings, Paul C; Yamaguchi, Yu; Koyama, Eiki; Pacifici, Maurizio
2013-05-01
During limb skeletogenesis the cartilaginous long bone anlagen and their growth plates become delimited by perichondrium with which they interact functionally. Yet, little is known about how, despite being so intimately associated with cartilage, perichondrium acquires and maintains its distinct phenotype and exerts its border function. Because perichondrium becomes deranged and interrupted by cartilaginous outgrowths in Hereditary Multiple Exostoses (HME), a pediatric disorder caused by EXT mutations and consequent heparan sulfate (HS) deficiency, we asked whether EXT genes and HS normally have roles in establishing its phenotype and function. Indeed, conditional Ext1 ablation in perichondrium and lateral chondrocytes flanking the epiphyseal region of mouse embryo long bone anlagen - a region encompassing the groove of Ranvier - caused ectopic cartilage formation. A similar response was observed when HS function was disrupted in long bone anlagen explants by genetic, pharmacological or enzymatic means, a response preceded by ectopic BMP signaling within perichondrium. These treatments also triggered excess chondrogenesis and cartilage nodule formation and overexpression of chondrogenic and matrix genes in limb bud mesenchymal cells in micromass culture. Interestingly, the treatments disrupted the peripheral definition and border of the cartilage nodules in such a way that many nodules overgrew and fused with each other into large amorphous cartilaginous masses. Interference with HS function reduced the physical association and interactions of BMP2 with HS and increased the cell responsiveness to endogenous and exogenous BMP proteins. In sum, Ext genes and HS are needed to establish and maintain perichondrium's phenotype and border function, restrain pro-chondrogenic signaling proteins including BMPs, and restrict chondrogenesis. Alterations in these mechanisms may contribute to exostosis formation in HME, particularly at the expense of regions rich in progenitor cells including the groove of Ranvier. Copyright © 2013 Elsevier Inc. All rights reserved.
[Extracellular matrix--regulation of cancer invasion and metastasis].
Watanabe, Hideto
2010-11-01
Cancer cell invasion comprises steps in the destruction of the basement membrane and migration of cells into the connective tissue. These cells further migrate into lymph ducts and small vessels to reach metastasis. The extracellular matrix (ECM) provides a microenvironment for cells, and its destruction is associated with cancer cell invasion. Among matrix metalloproteinases (MMPs), both MMP-2 and 9 digest type IV collagen, a major component of the basement membrane, and MMP-14/MT1-MMP, a membrane-type MMP, activates MMP-2. Thus, these MMPs play a central role in cancer cell invasion. MMPs also cleave latent forms of growth factors and signaling molecules, releasing and activating them, which influence neo-vascularization and cancer apoptosis. Like proteins, carbohydrates are known to be involved in cancer invasion. Hyaluronan is known to both stimulate and inhibit cancer invasion, depending on its molecular size. Heparanase, which digests heparan sulfate, is known to facilitate cancer invasion and metastasis. In summary, ECM provides a microenvironment that regulates cell behavior and its structure altered by MMPs affects cancer cell invasion.
Glycosaminoglycan synthesis by adult rat submandibular salivary-gland secretory units.
Cutler, L S; Christian, C P; Rendell, J K
1987-01-01
The synthesis of glycosaminoglycans (GAG) by a preparation of purified, functional submandibular-gland secretory units (acini and intercalated ducts) was examined. Such units were isolated from Sprague-Dawley rats by digestion of minced gland with hyaluronidase and collagenase followed by gentle sieving of the digest through a graded series of Teflon screens. They incorporated amino acids into exocrine proteins which could be released by stimulation with isoproterenol as in vivo, indicating their functional integrity. Secretory units, incubated for 2 h in medium containing [35S]-sodium sulphate alone or in combination with [3H]-glucosamine, were then washed, homogenized and digested in pronase. The resulting material was then sequentially digested by specific enzymic and chemical procedures and analysed by chromatography on Sephadex G-50 columns to identify the various GAG synthesized. Secretory units synthesized a GAG mixture which was 20-25 per cent hyaluronic acid, 70-75 per cent heparan sulphate, and only 3-5 per cent chondroitin or dermatan sulphates, similar to that synthesized in vivo. No GAG was present in the secretory material, suggesting that all the GAG synthesized was destined for the basement membrane or cell surface.
Ra, Hyun-Jeong; Harju-Baker, Susanna; Zhang, Fuming; Linhardt, Robert J.; Wilson, Carole L.; Parks, William C.
2009-01-01
Matrix metalloproteinases are maintained in an inactive state by a bond between the thiol of a conserved cysteine in the prodomain and a zinc atom in the catalytic domain. Once this bond is disrupted, MMPs become active proteinases and can act on a variety of extracellular protein substrates. In vivo, matrilysin (MMP7) activates pro-α-defensins (procryptdins), but in vitro, processing of these peptides is slow, with about 50% conversion in 8–12 h. Similarly, autolytic activation of promatrilysin in vitro can take up to 12–24 h for 50% conversion. These inefficient reactions suggest that natural cofactors enhance the activation and activity of matrilysin. We determined that highly sulfated glycosaminoglycans (GAG), such as heparin, chondroitin-4,6-sulfate (CS-E), and dermatan sulfate, markedly enhanced (>50-fold) the intermolecular autolytic activation of promatrilysin and the activity of fully active matrilysin to cleave specific physiologic substrates. In contrast, heparan sulfate and less sulfated forms of chondroitin sulfate did not augment matrilysin activation or activity. Chondroitin-2,6-sulfate (CS-D) also did not enhance matrilysin activity, suggesting that the presentation of sulfates is more important than the overall degree of sulfation. Surface plasmon resonance demonstrated that promatrilysin bound heparin (KD, 400 nm) and CS-E (KD, 630 nm). Active matrilysin bound heparin (KD, 150 nm) but less so to CS-E (KD, 60 μm). Neither form bound heparan sulfate. These observations demonstrate that sulfated GAGs regulate matrilysin activation and its activity against specific substrates. PMID:19654318
Farrugia, Brooke L; Lord, Megan S; Melrose, James; Whitelock, John M
2018-04-01
Key events that occur during inflammation include the recruitment, adhesion, and transmigration of leukocytes from the circulation to the site of inflammation. These events are modulated by chemokines, integrins, and selectins and the interaction of these molecules with glycosaminoglycans, predominantly heparan sulfate (HS). The development of HS/heparin mimetics that interfere or inhibit the interactions that occur between glycosaminoglycans and modulators of inflammation holds great potential for use as anti-inflammatory therapeutics. This review will detail the role of HS in the events that occur during inflammation, their interaction and modulation of inflammatory mediators, and the current advances in the development of HS/heparin mimetics as anti-inflammatory biotherapeutics.
Kariya, Yoshinobu; Sato, Hiroki; Katou, Naoko; Kariya, Yukiko; Miyazaki, Kaoru
2012-01-01
Laminin-332 (α3ß3γ2) (Lm332) supports the stable anchoring of basal keratinocytes to the epidermal basement membrane, while it functions as a motility factor for wound healing and cancer invasion. To understand these contrasting activities of Lm332, we investigated Lm332 matrices deposited by normal human keratinocytes and other Lm332-expressing cell lines. All types of the cells efficiently deposited Lm332 on the culture plates in specific patterns. On the contrary, laminins containing laminin ß1 and/or γ1 chains, such as Lm511 and Lm311, were not deposited on the culture plates even if secreted into culture medium. The Lm332 deposition was not inhibited by function-blocking antibodies to the α3 and α6 integrins but was inhibited by sodium selenate, suggesting that sulfated glycosaminoglycans on cell surface, e.g. heparan sulfate proteoglycans, might be involved in the process. HEK293 cells overexpressing exogenous Lm332 (Lm332-HEK) almost exclusively deposited Lm332 on the plates. The deposited Lm332 matrix showed a mesh-like network structure as analyzed by electron microscopy, suggesting that Lm332 was highly polymerized. When biological activity was analyzed, the Lm332 matrix rather suppressed the migration of keratinocytes as compared with purified Lm332, which highly promoted the cell migration. The Lm332 matrix supported adhesion of keratinocytes much more strongly and stably than purified Lm332. Integrin α3ß1 bound to the Lm332 matrix at a three times higher level than purified Lm332. Normal keratinocytes prominently showed integrin α6ß4-containing, hemidesmosome-like structures on the Lm332 matrix but not on the purified one. These results indicate that the polymerized Lm332 matrix supports stable cell adhesion by interacting with both integrin α6ß4 and α3ß1, whereas unassembled soluble Lm332 supports cell migration.
The Role of Heparan Sulfate Proteoglycans in Optic Disc and Stalk Morphogenesis
Cai, Zhigang; Grobe, Kay; Zhang, Xin
2014-01-01
Background Heparan sulfate proteoglycans (HSPG) are important for embryonic development via the regulation of gradient formation and signaling of multiple growth factors and morphogens. Previous studies have shown that Bmp/Shh/Fgf signaling are required for the regionalization of the optic vesicle (OV) and for the closure of the optic fissure (OF), the disturbance of which underlie ocular anomalies such as microphthalmia, coloboma and optic nerve hypoplasia. Results To study HSPG-dependent coordination of these signaling pathways during mammalian visual system development, we have generated a series of OV-specific mutations in the heparan sulfate (HS) N-sulfotransferase genes (Ndst1 and Ndst2) and HS O-sulfotransferase genes (Hs2st, Hs6st1 and Hs6st2) in mice. Interestingly, the resulting HS undersulfation still allowed for normal retinal neurogenesis and optic fissure closure, but led to defective optic disc and stalk development. The adult mutant animals further developed optic nerve aplasia/hypoplasia and displayed retinal degeneration. We observed that MAPK/ERK signaling was down-regulated in Ndst mutants, and consistent with this, HS-related optic nerve morphogenesis defects in mutant mice could partially be rescued by constitutive Kras activation. Conclusions These results suggest that HSPGs, depending on their HS sulfation pattern, regulate multiple signaling pathways in optic disc and stalk morphogenesis. PMID:24753163
Raats, C J; van den Born, J; Bakker, M A; Oppers-Walgreen, B; Pisa, B J; Dijkman, H B; Assmann, K J; Berden, J H
2000-05-01
The dystrophin-glycoprotein complex, which comprises alpha- and beta-dystroglycan, sarcoglycans, and utrophin/dystrophin, links the cytoskeleton to agrin and laminin in the basal lamina in muscle and epithelial cells. Recently, agrin was identified as a major heparan sulfate proteoglycan in the glomerular basement membrane. In the present study, we found mRNA expression for agrin, dystroglycan, and utrophin in kidney cortex, isolated glomeruli, and cultured podocytes and mesangial cells. In immunofluorescence, agrin was found in the glomerular basement membrane. The antibodies against alpha- and beta-dystroglycan and utrophin revealed a granular podocyte-like staining pattern along the glomerular capillary wall. With immunoelectron microscopy, agrin was found in the glomerular basement membrane, dystroglycan was diffusely found over the entire cell surface of the podocytes, and utrophin was localized in the cytoplasm of the podocyte foot processes. In adriamycin nephropathy, a decrease in the glomerular capillary wall staining for dystroglycan was observed probably secondary to the extensive fusion of foot processes. Immunoelectron microscopy showed a different distribution pattern as compared to the normal kidney, with segmentally enhanced expression of dystroglycan at the basal side of the extensively fused podocyte foot processes. In passive Heymann nephritis we observed no changes in the staining intensity and distribution of the dystrophin-glycoprotein complex by immunofluorescence and immunoelectron microscopy. From these data, we conclude that agrin, dystroglycan, and utrophin are present in the glomerular capillary wall and their ultrastructural localization supports the concept that these molecules are involved in linking the podocyte cytoskeleton to the glomerular basement membrane.
Raats, C. J. Ilse; van den Born, Jacob; Bakker, Marinka A. H.; Oppers-Walgreen, Birgitte; Pisa, Brenda J. M.; Dijkman, Henry B. P. M.; Assmann, Karel J. M.; Berden, Jo H. M.
2000-01-01
The dystrophin-glycoprotein complex, which comprises α- and β-dystroglycan, sarcoglycans, and utrophin/dystrophin, links the cytoskeleton to agrin and laminin in the basal lamina in muscle and epithelial cells. Recently, agrin was identified as a major heparan sulfate proteoglycan in the glomerular basement membrane. In the present study, we found mRNA expression for agrin, dystroglycan, and utrophin in kidney cortex, isolated glomeruli, and cultured podocytes and mesangial cells. In immunofluorescence, agrin was found in the glomerular basement membrane. The antibodies against α- and β-dystroglycan and utrophin revealed a granular podocyte-like staining pattern along the glomerular capillary wall. With immunoelectron microscopy, agrin was found in the glomerular basement membrane, dystroglycan was diffusely found over the entire cell surface of the podocytes, and utrophin was localized in the cytoplasm of the podocyte foot processes. In adriamycin nephropathy, a decrease in the glomerular capillary wall staining for dystroglycan was observed probably secondary to the extensive fusion of foot processes. Immunoelectron microscopy showed a different distribution pattern as compared to the normal kidney, with segmentally enhanced expression of dystroglycan at the basal side of the extensively fused podocyte foot processes. In passive Heymann nephritis we observed no changes in the staining intensity and distribution of the dystrophin-glycoprotein complex by immunofluorescence and immunoelectron microscopy. From these data, we conclude that agrin, dystroglycan, and utrophin are present in the glomerular capillary wall and their ultrastructural localization supports the concept that these molecules are involved in linking the podocyte cytoskeleton to the glomerular basement membrane. PMID:10793086
p27 Nuclear localization and growth arrest caused by perlecan knockdown in human endothelial cells
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sakai, Katsuya; Oka, Kiyomasa; Matsumoto, Kunio
2010-02-12
Perlecan, a secreted heparan sulfate proteoglycan, is a major component of the vascular basement membrane and participates in angiogenesis. Here, we used small interference RNA-mediated knockdown of perlecan expression to investigate the regulatory function of perlecan in the growth of human vascular endothelial cells. Basic fibroblast growth factor (bFGF)-induced ERK phosphorylation and cyclin D1 expression were unchanged by perlecan deficiency in endothelial cells; however, perlecan deficiency inhibited the Rb protein phosphorylation and DNA synthesis induced by bFGF. By contrast to cytoplasmic localization of the cyclin-dependent kinase inhibitor p27 in control endothelial cells, p27 was localized in the nucleus and itsmore » expression increased in perlecan-deficient cells, which suggests that p27 mediates inhibition of Rb phosphorylation. In addition to the well-characterized function of perlecan as a co-receptor for heparin-binding growth factors such as bFGF, our results suggest that perlecan plays an indispensible role in endothelial cell proliferation and acts through a mechanism that involves subcellular localization of p27.« less
Simonis, Alexander; Hebling, Sabrina; Gulbins, Erich; Schneider-Schaulies, Sibylle; Schubert-Unkmeir, Alexandra
2014-01-01
The interaction with brain endothelial cells is central to the pathogenicity of Neisseria meningitidis infections. Here, we show that N. meningitidis causes transient activation of acid sphingomyelinase (ASM) followed by ceramide release in brain endothelial cells. In response to N. meningitidis infection, ASM and ceramide are displayed at the outer leaflet of the cell membrane and condense into large membrane platforms which also concentrate the ErbB2 receptor. The outer membrane protein Opc and phosphatidylcholine-specific phospholipase C that is activated upon binding of the pathogen to heparan sulfate proteoglycans, are required for N. meningitidis-mediated ASM activation. Pharmacologic or genetic ablation of ASM abrogated meningococcal internalization without affecting bacterial adherence. In accordance, the restricted invasiveness of a defined set of pathogenic isolates of the ST-11/ST-8 clonal complex into brain endothelial cells directly correlated with their restricted ability to induce ASM and ceramide release. In conclusion, ASM activation and ceramide release are essential for internalization of Opc-expressing meningococci into brain endothelial cells, and this segregates with invasiveness of N. meningitidis strains. PMID:24945304
Jury, Elizabeth C.; Eldridge, Jillian; Isenberg, David A.; Kabouridis, Panagiotis S.
2008-01-01
It is shown in this study that the heparan sulfate proteoglycan agrin is overexpressed in T cells isolated from patients with the autoimmune disease systemic lupus erythematosus (SLE). Freshly isolated CD4+ and CD8+ subpopulations both exhibited higher expression over healthy controls, which however, gradually declined when cells were cultured in vitro. Agrin expression was induced following in vitro activation of cells via their Ag receptor, or after treatment with IFN-α, a cytokine shown to be pathogenic in lupus. Furthermore, serum from SLE patients with active disease was able to induce agrin expression when added to T cells from healthy donors, an increase that was partially blocked by neutralizing anti-IFN-α Abs. Cross-linking agrin with mAbs resulted in rapid reorganization of the actin cytoskeleton, activation of the ERK MAPK cascade, and augmentation of anti-CD3-induced proliferation and IL-10 production, indicating that agrin is a functional receptor in T cells. These results demonstrate that agrin expression in human T cells is regulated by cell activation and IFN-α, and may have an important function during cell activation with potential implications for autoimmunity. PMID:18025246
Baljinnyam, Erdene; Umemura, Masanari; Chuang, Christine; De Lorenzo, Mariana S; Iwatsubo, Mizuka; Chen, Suzie; Goydos, James S; Ishikawa, Yoshihiro; Whitelock, John M; Iwatsubo, Kousaku
2014-01-01
Fibroblast growth factor (FGF2) regulates endothelial and melanoma cell migration. The binding of FGF2 to its receptor requires N-sulfated heparan sulfate (HS) glycosamine. We have previously reported that Epac1, an exchange protein activated by cAMP, increases N-sulfation of HS in melanoma. Therefore, we examined whether Epac1 regulates FGF2-mediated cell–cell communication. Conditioned medium (CM) of melanoma cells with abundant expression of Epac1 increased migration of human umbilical endothelial cells (HUVEC) and melanoma cells with poor expression of Epac1. CM-induced increase in migration was inhibited by antagonizing FGF2, by the removal of HS and by the knockdown of Epac1. In addition, knockdown of Epac1 suppressed the binding of FGF2 to FGF receptor in HUVEC, and in vivo angiogenesis in melanoma. Furthermore, knockdown of Epac1 reduced N-sulfation of HS chains attached to perlecan, a major secreted type of HS proteoglycan that mediates the binding of FGF2 to FGF receptor. These data suggested that Epac1 in melanoma cells regulates melanoma progression via the HS–FGF2-mediated cell–cell communication. PMID:24725364
Heparanase expression in periapical granulomas and radicular cysts.
Elad, S; Sherman, Y; Palmon, A; Vlodavsky, I; Or, R
2013-01-01
Heparanase is an endo-β-D-glucuronidase enzyme which degrades heparan sulfate glycosaminoglycan side chains of proteoglycans in the extracellular matrix and in basement membranes. The aim of this study was to evaluate the expression of heparanase in periapical granulomas (PGs) and radicular cysts (RCs). Immunohistochemistry was used to assess heparanase expression in PGs and RCs. Parameters including stain intensity, location and cell type were used to characterize heparanase expression in the periapical lesions. Ordered categories (from weak to strong) were used to compare the level of heparanase staining in the PG and RC groups. Both epithelial cells and inflammatory cells were positive for heparanase. The relative staining of the epithelial cells was strong, whereas the relative staining of the inflammatory cells was weak. Significant differences in immunohistochemical staining of epithelial cells were observed between RCs and PGs (p = 0.002). The relative expression of heparanase in epithelial cells in RCs was strong. In PGs, lesions with few or no epithelial cells, heparanase was predominantly expressed weakly by inflammatory cells. PGs and RCs have the same infectious origin. Therefore, the different cellular sources of heparanase in these periapical lesions may imply that this enzyme has specific pathogenetic functions in RCs and PGs.
A Traveling Wave Ion Mobility Spectrometry (TWIMS) Study of the Robo1-Heparan Sulfate Interaction
NASA Astrophysics Data System (ADS)
Zhao, Yuejie; Yang, Jeong Yeh; Thieker, David F.; Xu, Yongmei; Zong, Chengli; Boons, Geert-Jan; Liu, Jian; Woods, Robert J.; Moremen, Kelley W.; Amster, I. Jonathan
2018-03-01
Roundabout 1 (Robo1) interacts with its receptor Slit to regulate axon guidance, axon branching, and dendritic development in the nervous system and to regulate morphogenesis and many cell functions in the nonneuronal tissues. This interaction is known to be critically regulated by heparan sulfate (HS). Previous studies suggest that HS is required to promote the binding of Robo1 to Slit to form the minimal signaling complex, but the molecular details and the structural requirements of HS for this interaction are still unclear. Here, we describe the application of traveling wave ion mobility spectrometry (TWIMS) to study the conformational details of the Robo1-HS interaction. The results suggest that Robo1 exists in two conformations that differ by their compactness and capability to interact with HS. The results also suggest that the highly flexible interdomain hinge region connecting the Ig1 and Ig2 domains of Robo1 plays an important functional role in promoting the Robo1-Slit interaction. Moreover, variations in the sulfation pattern and size of HS were found to affect its binding affinity and selectivity to interact with different conformations of Robo1. Both MS measurements and CIU experiments show that the Robo1-HS interaction requires the presence of a specific size and pattern of modification of HS. Furthermore, the effect of N-glycosylation on the conformation of Robo1 and its binding modes with HS is reported. [Figure not available: see fulltext.
Sanfilippo syndrome: causes, consequences, and treatments
Fedele, Anthony O
2015-01-01
Sanfilippo syndrome, or mucopolysaccharidosis (MPS) type III, refers to one of five autosomal recessive, neurodegenerative lysosomal storage disorders (MPS IIIA to MPS IIIE) whose symptoms are caused by the deficiency of enzymes involved exclusively in heparan sulfate degradation. The primary characteristic of MPS III is the degeneration of the central nervous system, resulting in mental retardation and hyperactivity, typically commencing during childhood. The significance of the order of events leading from heparan sulfate accumulation through to downstream changes in the levels of biomolecules within the cell and ultimately the (predominantly neuropathological) clinical symptoms is not well understood. The genes whose deficiencies cause the MPS III subtypes have been identified, and their gene products, as well as a selection of disease-causing mutations, have been characterized to varying degrees with respect to both frequency and direct biochemical consequences. A number of genetic and biochemical diagnostic methods have been developed and adopted by diagnostic laboratories. However, there is no effective therapy available for any form of MPS III, with treatment currently limited to clinical management of neurological symptoms. The availability of animal models for all forms of MPS III, whether spontaneous or generated via gene targeting, has contributed to improved understanding of the MPS III subtypes, and has provided and will deliver invaluable tools to appraise emerging therapies. Indeed, clinical trials to evaluate intrathecally-delivered enzyme replacement therapy in MPS IIIA patients, and gene therapy for MPS IIIA and MPS IIIB patients are planned or underway. PMID:26648750
Wilkin, Justin; Kerr, Natalie C; Byrd, Kathryn W; Ward, Jewell C; Iannaccone, Alessandro
2016-06-01
To report longitudinal phenotypic findings in a patient with Sanfilippo syndrome type IIIA, harboring SGSH mutations, one of which is novel. Heparan-N-sulfatidase enzyme function testing in skin fibroblasts and white blood cells and SGSH gene sequencing were obtained. Clinical office examinations, examinations under anesthesia, electroretinogram, spectral domain optical coherence tomography (SD-OCT), and fundus photography were performed over a 5-year period. Fundus examination revealed a progressive breadcrumb-like pigmentary retinopathy with perifoveal pigmentary involvement. SD-OCT showed loss of normal neuroretinal lamination and cystic macular changes responsive to treatment with carbonic anhydrase inhibitors. Electroretinography exhibited complex characteristics indicative of a generalized retinal rod > cone dysfunction with significant ON > OFF postreceptoral response compromise. Sequencing revealed compound heterozygous mutations in the SGSH gene, the novel c.88G > C (p.A30P) change and a second, previously reported one (c.734G > A, p.R245H). We have identified ocular features of a patient with Sanfilippo syndrome type IIIA harboring a novel SGHS mutation that were not previously known to occur in this disease - namely, a progressive retinopathy with distinctive features, cystic macular changes responsive to carbonic anhydrase inhibitors, and complex electroretinographic abnormalities consistent with postreceptoral dysfunction. SD-OCT imaging revealed retinal lamination changes consistent with previously reported histologic studies. Both the SD-OCT and the electroretinogram changes appear attributable to intraretinal deposition of heparan sulfate.
Stefanova, Margarita; Zemke, Katrin; Dimitrov, Boyan; Has, Christina; Kern, Johannes S; Bruckner-Tuderman, Leena; Kutsche, Kerstin
2005-10-01
Mutations in the type VII collagen gene (COL7A1) cause autosomal recessive and autosomal dominant inherited dystrophic epidermolysis bullosa (DEB). We report a family with three individuals who present blistering, scarring, hypo- and hyperpigmentation, and nail dystrophy suggestive for DEB. Whereas father and son carry a 5;13 translocation, the daughter shows a normal karyotype. Segregation analysis revealed that all affected family members inherited the same COL7A1 allele. Mutation analysis disclosed a heterozygous missense mutation, c.6227G > A (p.G2076D), in COL7A1 in all affected individuals. Delineation of the translocation breakpoints showed that the ERBB2IP (erbb2 interacting protein or Erbin) gene is disrupted in 5q13.1 and GPC6 in 13q32. GPC6 encodes glypican 6 belonging to a family of cell surface heparan sulfate proteoglycans. The binding partners of Erbin, BP230 (BPAG1) and the integrin beta4 subunit, both involved in hemidesmosome (HD) function, and the presence of Erbin in HD suggested that it plays a role in establishment and maintenance of cell-basement membrane adhesions. However, loss of function of one ERBB2IP copy or expression of a putative novel ERBB2IP fusion protein did not apparently modulate the DEB phenotype in both translocation patients. Nonetheless, one cannot yet exclude that ERBB2IP is a candidate for human blistering disorders such as epidermolysis bullosa.
Polysulfonate suramin inhibits Zika virus infection.
Tan, Chee Wah; Sam, I-Ching; Chong, Wei Lim; Lee, Vannajan Sanghiran; Chan, Yoke Fun
2017-07-01
Zika virus (ZIKV) is an arthropod-borne flavivirus that causes newborn microcephaly and Guillian-Barré syndrome in adults. No therapeutics are available to treat ZIKV infection or other flaviviruses. In this study, we explored the inhibitory effect of glycosaminoglycans and analogues against ZIKV infection. Highly sulfated heparin, dextran sulfate and suramin significantly inhibited ZIKV infection in Vero cells. De-sulfated heparin analogues lose inhibitory effect, implying that sulfonate groups are critical for viral inhibition. Suramin, an FDA-approved anti-parasitic drug, inhibits ZIKV infection with 3-5 log 10 PFU viral reduction with IC 50 value of ∼2.5-5 μg/ml (1.93 μM-3.85 μM). A time-of-drug-addition study revealed that suramin remains potent even when administrated at 1-24 hpi. Suramin inhibits ZIKV infection by preventing viral adsorption, entry and replication. Molecular dynamics simulation revealed stronger interaction of suramin with ZIKV NS3 helicase than with the envelope protein. Suramin warrants further investigation as a potential antiviral candidate for ZIKV infection. Heparan sulfate (HS) is a cellular attachment receptor for multiple flaviviruses. However, no direct ZIKV-heparin interaction was observed in heparin-binding analysis, and downregulate or removal of cellular HS with sodium chlorate or heparinase I/III did not inhibit ZIKV infection. This indicates that cell surface HS is not utilized by ZIKV as an attachment receptor. Copyright © 2017 Elsevier B.V. All rights reserved.
Sandeep, M S; Nandini, C D
2017-08-01
In-utero exposure of foetus to hyperglycaemic condition affects the growth and development of the organism. The brain is one of the first organs that start to develop during embryonic period and glycosaminoglycans (GAGs) and proteoglycans (PGs) are one of the key molecules involved in its development. But studies on the effect of hyperglycaemic conditions on brain GAGs/PGs are few and far between. We, therefore, looked into the changes in brain GAGs and PGs at various developmental stages of pre- and post-natal rats from non-diabetic and diabetic mothers as well as in adult rats induced with diabetes using a diabetogenic agent, Streptozotocin. Increased expression of GAGs especially that of heparan sulphate class in various developmental stages were observed in the brain as a result of in-utero hyperglycaemic condition but not in that of adult rats. Changes in disaccharides of heparan sulphate (HS) were observed in various developmental stages. Furthermore, various HSPGs namely, syndecans-1 and -3 and glypican-1 were overexpressed in offspring from diabetic mother. However, in adult diabetic rats, only glypican-1 was overexpressed. The offsprings from diabetic mothers became hyperphagic at the end of 8 weeks after birth which can have implications in the long run. Our results highlight the likely impact of the in-utero exposure of foetus to hyperglycaemic condition on brain GAGs/PGs compared to diabetic adult rats.
Boado, Ruben J; Lu, Jeff Zhiqiang; Hui, Eric Ka-Wai; Pardridge, William M
2018-02-05
Mucopolysaccharidosis Type IIIA (MPSIIIA), also known as Sanfilippo A syndrome, is an inherited neurodegenerative disease caused by mutations in the lysosomal enzyme, N-sulfoglucosamine sulfohydrolase (SGSH), also known as sulfamidase. Mutations in the SGSH enzyme, the only mammalian heparan N-sulfatase, cause accumulation of lysosomal inclusion bodies in brain cells comprising heparan sulfate (HS) glycosaminoglycans (GAGs). Treatment of MPSIIIA with intravenous recombinant SGSH is not possible because this large molecule does not cross the blood-brain barrier (BBB). BBB penetration by SGSH was enabled in the present study by re-engineering this enzyme as an IgG-SGSH fusion protein, where the IgG domain is a chimeric monoclonal antibody (mAb) against the mouse transferrin receptor (TfR), designated the cTfRMAb. The IgG domain of the fusion protein acts as a molecular Trojan horse to deliver the enzyme into brain via transport on the endogenous BBB TfR. The cTfRMAb-SGSH fusion protein bound to the mouse TfR with high affinity, ED 50 = 0.74 ± 0.07 nM, and retained high SGSH enzyme activity, 10 043 ± 1003 units/mg protein, which is comparable to recombinant human SGSH. Male and female MPSIIIA mice, null for the SGSH enzyme, were treated for 6 weeks with thrice-weekly intraperitoneal injections of vehicle, 5 mg/kg of the cTfRMAb alone, or 5 mg/kg of the cTfRMAb-SGSH fusion protein, starting at the age of 2 weeks, and were euthanized 1 week after the last injection. Brain and liver HS, as determined by liquid chromatography-mass spectrometry, were elevated 30-fold and 36-fold, respectively, in the MPSIIIA mouse. Treatment of the mice with the cTfRMAb-SGSH fusion protein caused a 70% and 85% reduction in brain and liver HS, respectively. The reduction in brain HS was associated with a 28% increase in latency on the rotarod test of motor activity in male mice. The mice exhibited no injection related reactions, and only a low titer end of study antidrug antibody response was observed. In conclusion, substantial reductions in brain pathologic GAGs in a murine model of MPSIIIA are produced by chronic systemic administration of an IgG-SGSH fusion protein engineered to penetrate the BBB via receptor-mediated transport.
Schwieterman, Alicia A.; Steves, Alyse N.; Yee, Vivian; Donelson, Cory J.; Bentley, Melissa R.; Santorella, Elise M.; Mehlenbacher, Taylor V.; Pital, Aaron; Howard, Austin M.; Wilson, Melissa R.; Ereddia, Danielle E.; Effrein, Kelsie S.; McMurry, Jonathan L.; Ackley, Brian D.; Chisholm, Andrew D.; Hudson, Martin L.
2016-01-01
The Eph receptors and their cognate ephrin ligands play key roles in many aspects of nervous system development. These interactions typically occur within an individual tissue type, serving either to guide axons to their terminal targets or to define boundaries between the rhombomeres of the hindbrain. We have identified a novel role for the Caenorhabditis elegans ephrin EFN-4 in promoting primary neurite outgrowth in AIY interneurons and D-class motor neurons. Rescue experiments reveal that EFN-4 functions non-cell autonomously in the epidermis to promote primary neurite outgrowth. We also find that EFN-4 plays a role in promoting ectopic axon branching in a C. elegans model of X-linked Kallmann syndrome. In this context, EFN-4 functions non-cell autonomously in the body-wall muscle and in parallel with HS modification genes and HSPG core proteins. This is the first report of an epidermal ephrin providing a developmental cue to the nervous system. PMID:26645816
Ramachandra, Rashmi; Namburi, Ramesh B; Ortega-Martinez, Olga; Shi, Xiaofeng; Zaia, Joseph; Dupont, Sam T; Thorndyke, Michael C; Lindahl, Ulf; Spillmann, Dorothe
2014-02-01
Glycosaminoglycans (GAGs) isolated from brittlestars, Echinodermata class Ophiuroidea, were characterized, as part of attempts to understand the evolutionary development of these polysaccharides. A population of chondroitin sulfate/dermatan sulfate (CS/DS) chains with a high overall degree of sulfation and hexuronate epimerization was the major GAG found, whereas heparan sulfate (HS) was below detection level. Enzymatic digestion with different chondroitin lyases revealed exceptionally high proportions of di- and trisulfated CS/DS disaccharides. The latter unit appears much more abundant in one of four individual species of brittlestars, Amphiura filiformis, than reported earlier in other marine invertebrates. The brittlestar CS/DS was further shown to bind to growth factors such as fibroblast growth factor 2 and to promote FGF-stimulated cell signaling in GAG-deficient cell lines in a manner similar to that of heparin. These findings point to a potential biological role for the highly sulfated invertebrate GAGs, similar to those ascribed to HS in vertebrates.
Imaging specific cellular glycan structures using glycosyltransferases via click chemistry.
Wu, Zhengliang L; Person, Anthony D; Anderson, Matthew; Burroughs, Barbara; Tatge, Timothy; Khatri, Kshitij; Zou, Yonglong; Wang, Lianchun; Geders, Todd; Zaia, Joseph; Sackstein, Robert
2018-02-01
Heparan sulfate (HS) is a polysaccharide fundamentally important for biologically activities. T/Tn antigens are universal carbohydrate cancer markers. Here, we report the specific imaging of these carbohydrates using a mesenchymal stem cell line and human umbilical vein endothelial cells (HUVEC). The staining specificities were demonstrated by comparing imaging of different glycans and validated by either removal of target glycans, which results in loss of signal, or installation of target glycans, which results in gain of signal. As controls, representative key glycans including O-GlcNAc, lactosaminyl glycans and hyaluronan were also imaged. HS staining revealed novel architectural features of the extracellular matrix (ECM) of HUVEC cells. Results from T/Tn antigen staining suggest that O-GalNAcylation is a rate-limiting step for O-glycan synthesis. Overall, these highly specific approaches for HS and T/Tn antigen imaging should greatly facilitate the detection and functional characterization of these biologically important glycans. © The Author(s) 2017. Published by Oxford University Press.
Heparanase-2 and syndecan-1 in colon cancer: the ugly ducklings or the beautiful swans?
Giordano, Ricardo José
2008-08-01
Syndecan expression, or the lack thereof by tumor cells, has been associated with poor prognosis in several types of cancer, including colorectal cancer. Syndecan is a heparan sulfate proteoglycan involved in tumor adhesion, invasion, and metastasis. In addition, the expression of the enzyme heparanase by cancer cells correlates with malignant transformation and metastasis. Given the prominent role of syndecan and heparanase in physiological and pathological processes, they are promising molecular targets in the development of diagnostic methods and drugs for cancer and other diseases. A study in this issue of the European Journal of Gastroenterology & Hepatology reports the expression of syndecan-1 (Syn-1) and HPA2 in human colorectal cancer samples. These results confirm earlier observations that Syn-1 is downregulated by colorectal carcinoma cells but raise questions about its prognostic value. This study is also the first report on the upregulation of HPA2 in human cancer samples. HPA2 and Syn-1 expression by colorectal cancer tumor cells and the possible implications in disease progression are discussed.
Heparanase promotes tumor infiltration and antitumor activity of CAR-redirected T-lymphocytes
Caruana, Ignazio; Savoldo, Barbara; Hoyos, Valentina; Weber, Gerrit; Liu, Hao; Kim, Eugene S.; Ittmann, Michael M.; Marchetti, Dario; Dotti, Gianpietro
2015-01-01
Adoptive transfer of chimeric antigen receptor (CAR)-redirected T lymphocytes (CAR-T cells) has had less striking effects in solid tumors1–3 than in lymphoid malignancies4, 5. Although active tumor-mediated immunosuppression may play a role in limiting efficacy6, functional changes in T lymphocytes following their ex vivo manipulation may also account for cultured CAR-T cells’ reduced ability to penetrate stroma-rich solid tumors. We therefore studied the capacity of human in vitro-cultured CAR-T cells to degrade components of the extracellular matrix (ECM). In contrast to freshly isolated T lymphocytes, we found that in vitro-cultured T lymphocytes lack expression of the enzyme heparanase (HPSE) that degrades heparan sulphate proteoglycans, which are main components of ECM. We found that HPSE mRNA is down regulated in in vitro-expanded T cells, which may be a consequence of p53 binding to the HPSE gene promoter. We therefore engineered CAR-T cells to express HPSE and showed improved capacity to degrade ECM, which promoted tumor T-cell infiltration and antitumor activity. Employing this strategy may enhance the activity of CAR-T cells in individuals with stroma-rich solid tumors. PMID:25849134
Bai, Xingwen; Bao, Huifang; Li, Pinghua; Wei, Wei; Zhang, Meng; Sun, Pu; Cao, Yimei; Lu, Zengjun; Fu, Yuanfang; Xie, Baoxia; Chen, Yingli; Li, Dong; Luo, Jianxun; Liu, Zaixin
2014-07-24
Some cell-adapted strains of foot-and-mouth disease virus (FMDV) can utilize heparan sulfate (HS) as a receptor to facilitate viral infection in cultured cells. A number of independent sites on the capsid that might be involved in FMDV-HS interaction have been studied. However, the previously reported residues do not adequately explain HS-dependent infection of two cell-adapted PanAsia-1 strains (O/Tibet/CHA/6/99tc and O/Fujian/CHA/9/99tc) of FMDV serotype O. To identify the molecular determinant(s) for the interaction of O/Tibet/CHA/6/99tc and O/Fujian/CHA/9/99tc with HS receptor, several chimeric viruses and site-directed mutants were generated by using an infectious cDNA of a non-HS-utilizing rescued virus (Cathay topotype) as the genomic backbone. Phenotypic properties of these viruses were determined by plaque assays and virus adsorption and penetration assays in cultured cells. Only two of the rescued viruses encoding VP0 of O/Tibet/CHA/6/99tc or VP1 of O/Fujian/CHA/9/99tc formed plaques on wild-type Chinese hamster ovary (WT-CHO; HS+) cells, but not on HS-negative pgsD-677 cells. The formation of plaques by these two chimeric viruses on WT-CHO cells could be abolished by the introduction of single amino acid mutations Gln-2080 → Leu in VP2 of O/Tibet/CHA/6/99tc and Lys-1083 → Glu in VP1 of O/Fujian/CHA/9/99tc, respectively. Nonetheless, the introduced mutation Leu-2080 → Gln in VP2 of O/Fujian/CHA/9/99tc for the construction of expectant recombinant plasmid led to non-infectious progeny virus in baby hamster kidney 21 (BHK-21) cells, and the site-directed mutant encoding Glu-1083 → Lys in VP1 of O/Tibet/CHA/6/99tc did not acquire the ability to produce plaques on WT-CHO cells. Significant differences in the inhibition of the infectivity of four HS-utilizing viruses by heparin and RGD-containing peptide were observed in BHK-21 cells. Interestingly, the chimeric virus encoding VP0 of O/Fujian/CHA/9/99tc, and the site-directed mutant encoding Gln-2080 → Leu in VP2 of O/Tibet/CHA/6/99tc could bind to HS, but there was no expression of the 3A protein of these two viruses in WT-CHO cells. The results suggest that the cooperation of certain specific amino acid residues in the capsid proteins of these two cell-adapted PanAsia-1 strains is essential for viral infectivity, the heparin affinity and the capability on FMDV-HS interaction.
2014-01-01
Background Some cell-adapted strains of foot-and-mouth disease virus (FMDV) can utilize heparan sulfate (HS) as a receptor to facilitate viral infection in cultured cells. A number of independent sites on the capsid that might be involved in FMDV-HS interaction have been studied. However, the previously reported residues do not adequately explain HS-dependent infection of two cell-adapted PanAsia-1 strains (O/Tibet/CHA/6/99tc and O/Fujian/CHA/9/99tc) of FMDV serotype O. To identify the molecular determinant(s) for the interaction of O/Tibet/CHA/6/99tc and O/Fujian/CHA/9/99tc with HS receptor, several chimeric viruses and site-directed mutants were generated by using an infectious cDNA of a non-HS-utilizing rescued virus (Cathay topotype) as the genomic backbone. Phenotypic properties of these viruses were determined by plaque assays and virus adsorption and penetration assays in cultured cells. Results Only two of the rescued viruses encoding VP0 of O/Tibet/CHA/6/99tc or VP1 of O/Fujian/CHA/9/99tc formed plaques on wild-type Chinese hamster ovary (WT-CHO; HS+) cells, but not on HS-negative pgsD-677 cells. The formation of plaques by these two chimeric viruses on WT-CHO cells could be abolished by the introduction of single amino acid mutations Gln-2080 → Leu in VP2 of O/Tibet/CHA/6/99tc and Lys-1083 → Glu in VP1 of O/Fujian/CHA/9/99tc, respectively. Nonetheless, the introduced mutation Leu-2080 → Gln in VP2 of O/Fujian/CHA/9/99tc for the construction of expectant recombinant plasmid led to non-infectious progeny virus in baby hamster kidney 21 (BHK-21) cells, and the site-directed mutant encoding Glu-1083 → Lys in VP1 of O/Tibet/CHA/6/99tc did not acquire the ability to produce plaques on WT-CHO cells. Significant differences in the inhibition of the infectivity of four HS-utilizing viruses by heparin and RGD-containing peptide were observed in BHK-21 cells. Interestingly, the chimeric virus encoding VP0 of O/Fujian/CHA/9/99tc, and the site-directed mutant encoding Gln-2080 → Leu in VP2 of O/Tibet/CHA/6/99tc could bind to HS, but there was no expression of the 3A protein of these two viruses in WT-CHO cells. Conclusion The results suggest that the cooperation of certain specific amino acid residues in the capsid proteins of these two cell-adapted PanAsia-1 strains is essential for viral infectivity, the heparin affinity and the capability on FMDV-HS interaction. PMID:25056022
Syndecan-4 shedding impairs macrovascular angiogenesis in diabetes mellitus
DOE Office of Scientific and Technical Information (OSTI.GOV)
Li, Ran; Xie, Jun; Wu, Han
Purpose: Syndecan-4 (synd4) is a ubiquitous heparan sulfate proteoglycan cell surface receptor that modulates cell proliferation, migration, mechanotransduction, and endocytosis. The extracellular domain of synd4 sheds heavily in acute inflammation, but the shedding of synd4 in chronic inflammation, such as diabetes mellitus (DM), is still undefined. We investigated the alterations of synd4 endothelial expression in DM and the influence of impaired synd4 signaling on angiogenesis in human umbilical vein endothelial cells (HUVECs), diabetic rats, synd4 null mice, and db/db mice. Material and methods: HUVECs were incubated with advanced glycation end products (AGEs). Western blot analysis was used to determine synd4more » protein expression and ELISA was used to detect soluble synd4 fragments. The concentration of synd4 in the aortic endothelia of diabetic rats was detected by immunohistochemical staining. Aortic ring assays were performed to study the process of angiogenesis in the diabetic rats and in synd4 null and db/db mice. Recombinant adenoviruses containing the synd4 gene or null were constructed to enhance synd4 aortic expression in db/db mice. Results: Western blot analysis showed decreased expression of the synd4 extracellular domain in HUVECs, and ELISA detected increased soluble fragments of synd4 in the media. Synd4 endothelial expression in the aortas of diabetic rats was decreased. Aortic ring assay indicated impaired angiogenesis in synd4 null and db/db mice, which was partially reversed by synd4 overexpression in db/db mice. Conclusion: Synd4 shedding from vascular endothelial cells played an important role in the diabetes-related impairment of angiogenesis. -- Highlights: •Synd4 shedding from endothelial cells is accelerated under the stimulation of AGEs. •Extracellular domain of synd4 is diminished in the endothelium of DM rats. •Aortic rings of synd4 null mice showed impaired angiogenesis. •Overexpression of synd4 partly rescues macrovascular angiogenesis in db/db mice.« less
Viral and Cellular Determinants of the Hepatitis C Virus Envelope-Heparan Sulfate Interaction▿
Barth, Heidi; Schnober, Eva K.; Zhang, Fuming; Linhardt, Robert J.; Depla, Erik; Boson, Bertrand; Cosset, Francois-Loic; Patel, Arvind H.; Blum, Hubert E.; Baumert, Thomas F.
2006-01-01
Cellular binding and entry of hepatitis C virus (HCV) are the first steps of viral infection and represent a major target for antiviral antibodies and novel therapeutic strategies. We have recently demonstrated that heparan sulfate (HS) plays a key role in the binding of HCV envelope glycoprotein E2 to target cells (Barth et al., J. Biol. Chem. 278:41003-41012, 2003). In this study, we characterized the HCV-HS interaction and analyzed its inhibition by antiviral host immune responses. Using recombinant envelope glycoproteins, virus-like particles, and HCV pseudoparticles as model systems for the early steps of viral infection, we mapped viral and cellular determinants of HCV-HS interaction. HCV-HS binding required a specific HS structure that included N-sulfo groups and a minimum of 10 to 14 saccharide subunits. HCV envelope binding to HS was mediated by four viral epitopes overlapping the E2 hypervariable region 1 and E2-CD81 binding domains. In functional studies using HCV pseudoparticles, we demonstrate that HCV binding and entry are specifically inhibited by highly sulfated HS. Finally, HCV-HS binding was markedly inhibited by antiviral antibodies derived from HCV-infected individuals. In conclusion, our results demonstrate that binding of the viral envelope to a specific HS configuration represents an important step for the initiation of viral infection and is a target of antiviral host immune responses in vivo. Mapping of viral and cellular determinants of HCV-HS interaction sets the stage for the development of novel HS-based antiviral strategies targeting viral attachment and entry. PMID:16928753
Expression of heparanase in basal cell carcinoma and squamous cell carcinoma.
Pinhal, Maria Aparecida Silva; Almeida, Maria Carolina Leal; Costa, Alessandra Scorse; Theodoro, Thérèse Rachell; Serrano, Rodrigo Lorenzetti; Machado, Carlos D'Apparecida Santos
2016-01-01
Heparanase is an enzyme that cleaves heparan sulfate chains. Oligosaccharides generated by heparanase induce tumor progression. Basal cell carcinoma and squamous cell carcinoma comprise types of nonmelanoma skin cancer. Evaluate the glycosaminoglycans profile and expression of heparanase in two human cell lines established in culture, immortalized skin keratinocyte (HaCaT) and squamous cell carcinoma (A431) and also investigate the expression of heparanase in basal cell carcinoma, squamous cell carcinoma and eyelid skin of individuals not affected by the disease (control). Glycosaminoglycans were quantified by electrophoresis and indirect ELISA method. The heparanase expression was analyzed by quantitative RT-PCR (qRTPCR). The A431 strain showed significant increase in the sulfated glycosaminoglycans, increased heparanase expression and decreased hyaluronic acid, comparing to the HaCaT lineage. The mRNA expression of heparanase was significantly higher in Basal cell carcinoma and squamous cell carcinoma compared with control skin samples. It was also observed increased heparanase expression in squamous cell carcinoma compared to the Basal cell carcinoma. The glycosaminoglycans profile, as well as heparanase expression are different between HaCaT and A431 cell lines. The increased expression of heparanase in Basal cell carcinoma and squamous cell carcinoma suggests that this enzyme could be a marker for the diagnosis of such types of non-melanoma cancers, and may be useful as a target molecule for future alternative treatment.
Heparin: Past, Present, and Future.
Oduah, Eziafa I; Linhardt, Robert J; Sharfstein, Susan T
2016-07-04
Heparin, the most widely used anticoagulant drug in the world today, remains an animal-derived product with the attendant risks of adulteration and contamination. A contamination crisis in 2007-2008 increased the impetus to provide non-animal-derived sources of heparin, produced under cGMP conditions. In addition, recent studies suggest that heparin may have significant antineoplastic activity, separate and distinct from its anticoagulant activity, while other studies indicate a role for heparin in treating inflammation, infertility, and infectious disease. A variety of strategies have been proposed to produce a bioengineered heparin. In this review, we discuss several of these strategies including microbial production, mammalian cell production, and chemoenzymatic modification. We also propose strategies for creating "designer" heparins and heparan-sulfates with various biochemical and physiological properties.
Marolla, Ana Paula Cleto; Waisberg, Jaques; Saba, Gabriela Tognini; Waisberg, Daniel Reis; Margeotto, Fernando Beani; Pinhal, Maria Aparecida da Silva
2015-01-01
To determine the presence of glycosaminoglycans in the extracellular matrix of connective tissue from neoplastic and non-neoplastic colorectal tissues, since it has a central role in tumor development and progression. Tissue samples from neoplastic and non-neoplastic colorectal tissues were obtained from 64 operated patients who had colorectal carcinoma with no distant metastases. Expressions of heparan sulphate, chondroitin sulphate, dermatan sulphate and their fragments were analyzed by electrospray ionization mass spectrometry, with the technique for extraction and quantification of glycosaminoglycans after proteolysis and electrophoresis. The statistical analysis included mean, standard deviation, and Student'st test. The glycosaminoglycans extracted from colorectal tissue showed three electrophoretic bands in agarose gel. Electrospray ionization mass spectrometry showed characteristic disaccharide fragments from glycosaminoglycans, indicating their structural characterization in the tissues analyzed. Some peaks in the electrospray ionization mass spectrometry were not characterized as fragments of sugars, indicating the presence of fragments of the protein structure of proteoglycans generated during the glycosaminoglycan purification. The average amount of chondroitin and dermatan increased in the neoplastic tissue compared to normal tissue (p=0.01). On the other hand, the average amount of heparan decreased in the neoplastic tissue compared to normal tissue (p= 0.03). The method allowed the determination of the glycosaminoglycans structural profile in colorectal tissue from neoplastic and non-neoplastic colorectal tissue. Neoplastic tissues showed greater amounts of chondroitin sulphate and dermatan sulphate compared to non-neoplastic tissues, while heparan sulphate was decreased in neoplastic tissues.
Khademi, Farzaneh; Ai, Jafar; Soleimani, Masoud; Verdi, Javad; Mohammad Tavangar, Seyed; Sadroddiny, Esmaeil; Massumi, Mohammad; Mahmoud Hashemi, Seyed
2017-11-01
Liver tissue engineering (TE) is rapidly emerging as an effective technique which combines engineering and biological processes to compensate for the shortage of damaged or destroyed liver tissues. We examined the viability, differentiation, and integration of hepatocyte-like cells on an electrospun polyethersulfone (PES) scaffold, derived from human endometrial stem cells (hEnSCs). Natural polymers were separately grafted on plasma-treated PES nanofibers, that is, collagen, heparan sulfate (HS) and collagen-HS. Galactosilated PES (PES-Gal) nanofibrous were created. The engineering and cell growth parameters were considered and compared with each sample. The cellular studies revealed increased cell survival, attachment, and normal morphology on the bioactive natural polymer-grafted scaffolds after 30 days of hepatic differentiation. The chemical and molecular assays displayed hepatocyte differentiation. These cells were also functional, showing glycogen storage, α-fetoprotein, and albumin secretion. The HS nanoparticle-grafted PES nanofibers demonstrated a high rate of cell proliferation, differentiation, and integration. Based on the observations mentioned above, engineered tissue is a good option in the future, for the commercial production of three-dimensional liver tissues for clinical purposes. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2516-2529, 2017. © 2016 Wiley Periodicals, Inc.
Bienkowska-Haba, Malgorzata; Williams, Carlyn; Kim, Seong Man; Garcea, Robert L; Sapp, Martin
2012-09-01
Human papillomaviruses (HPV) are composed of the major and minor capsid proteins, L1 and L2, that encapsidate a chromatinized, circular double-stranded DNA genome. At the outset of infection, the interaction of HPV type 16 (HPV16) (pseudo)virions with heparan sulfate proteoglycans triggers a conformational change in L2 that is facilitated by the host cell chaperone cyclophilin B (CyPB). This conformational change results in exposure of the L2 N terminus, which is required for infectious internalization. Following internalization, L2 facilitates egress of the viral genome from acidified endosomes, and the L2/DNA complex accumulates at PML nuclear bodies. We recently described a mutant virus that bypasses the requirement for cell surface CyPB but remains sensitive to cyclosporine for infection, indicating an additional role for CyP following endocytic uptake of virions. We now report that the L1 protein dissociates from the L2/DNA complex following infectious internalization. Inhibition and small interfering RNA (siRNA)-mediated knockdown of CyPs blocked dissociation of L1 from the L2/DNA complex. In vitro, purified CyPs facilitated the dissociation of L1 pentamers from recombinant HPV11 L1/L2 complexes in a pH-dependent manner. Furthermore, CyPs released L1 capsomeres from partially disassembled HPV16 pseudovirions at slightly acidic pH. Taken together, these data suggest that CyPs mediate the dissociation of HPV L1 and L2 capsid proteins following acidification of endocytic vesicles.
Bienkowska-Haba, Malgorzata; Williams, Carlyn; Kim, Seong Man; Garcea, Robert L.
2012-01-01
Human papillomaviruses (HPV) are composed of the major and minor capsid proteins, L1 and L2, that encapsidate a chromatinized, circular double-stranded DNA genome. At the outset of infection, the interaction of HPV type 16 (HPV16) (pseudo)virions with heparan sulfate proteoglycans triggers a conformational change in L2 that is facilitated by the host cell chaperone cyclophilin B (CyPB). This conformational change results in exposure of the L2 N terminus, which is required for infectious internalization. Following internalization, L2 facilitates egress of the viral genome from acidified endosomes, and the L2/DNA complex accumulates at PML nuclear bodies. We recently described a mutant virus that bypasses the requirement for cell surface CyPB but remains sensitive to cyclosporine for infection, indicating an additional role for CyP following endocytic uptake of virions. We now report that the L1 protein dissociates from the L2/DNA complex following infectious internalization. Inhibition and small interfering RNA (siRNA)-mediated knockdown of CyPs blocked dissociation of L1 from the L2/DNA complex. In vitro, purified CyPs facilitated the dissociation of L1 pentamers from recombinant HPV11 L1/L2 complexes in a pH-dependent manner. Furthermore, CyPs released L1 capsomeres from partially disassembled HPV16 pseudovirions at slightly acidic pH. Taken together, these data suggest that CyPs mediate the dissociation of HPV L1 and L2 capsid proteins following acidification of endocytic vesicles. PMID:22761365
Hatori, N; Sjöquist, P O; Marklund, S L; Rydén, L
1992-09-01
The efficacy of human extracellular-superoxide dismutase type C (EC-SOD C) to limit infarct size after ischemia and reperfusion was explored and compared to that of EC-SOD C combined with catalase (CAT) and to that of CAT alone. EC-SOD C binds to heparan sulphate proteoglycan on the cell surfaces. Thirty-two pigs were subjected to 45 min of myocardial ischemia followed by 4 h of reperfusion. Control pigs (group A; n = 8) received 300 mL of saline into the great cardiac vein during a 30-min period started 5 min prior to reperfusion; pigs in group B (EC-SOD C; n = 8) got 16.6 mg of EC-SOD C; pigs in group C (EC-SOD C + CAT; n = 8) got 16.6 mg of EC-SOD C together with 150 mg of CAT. Pigs in group D (CAT; n = 8) received 150 mg of CAT. In groups B, C, and D, the drug was dissolved in saline and infused into the great cardiac. Infarct size expressed as percent of area at risk was smaller in groups B (14.5 +/- 16.7%) and C (40.8 +/- 13.3%) than in groups A (78.8 +/- 8.6%) and D (67.2 +/- 18.6%; p less than .05). Creatine kinase (CK) activity in ischemic myocardium was higher in groups B (1740 +/- 548 U/g) and C (1729 +/- 358 U/g) than in groups A (1184 +/- 237 U/g) and D (1251 +/- 434 U/g; p less than .05). There was an inverse relation (r = -.83) between infarct size and CK content. The EC-SOD C infusions resulted in only minimal increases in plasma SOD activities. In conclusion, the presence of SOD on the cell surfaces is of importance in the prevention of reperfusion injury rather than circulating SOD.
Khurana, Ashwani; Jung-Beom, Deok; He, Xiaoping; Kim, Sung-Hoon; Busby, Robert C.; Lorenzon, Laura; Villa, Massimo; Baldi, Alfonso; Molina, Julian; Goetz, Matthew P.; Shridhar, Viji
2013-01-01
Sulfatase 2 (Sulf-2) has been previously shown to be upregulated in breast cancer. Sulf-2 removes sulfate moieties on heparan sulfate proteoglycans which in turn modulate heparin binding growth factor signaling. Here we report that matrix detachment resulted in decreased Sulf-2 expression in breast cancer cells and increased cleavage of poly ADP-ribose polymerase. Silencing of Sulf-2 promotes matrix detachment induced cell death in MCF10DCIS cells. In an attempt to identify Sulf-2 specific inhibitor, we found that proteasomal inhibitors such as MG132, Lactacystin and Bortezomib treatment abolished Sulf-2 expression in multiple breast cancer cell lines. Additionally, we show that Bortezomib treatment of MCF10DCIS cell xenografts in mouse mammary fat pads significantly reduced tumor size, caused massive apoptosis and more importantly reduced Sulf-2 levels in vivo. Finally, our immunohistochemistry analysis of Sulf-2 expression in cohort of patient derived breast tumors indicates that Sulf-2 is significantly upregulated in autologous metastatic lesions compared to primary tumors (p < 0.037, Pearson correlation, Chi-Square analysis). In all, our data suggest that Sulf-2 might play an important role in breast cancer progression from ductal carcinoma in situ into an invasive ductal carcinoma potentially by resisting cell death. PMID:23412907
Chammas, Oliver; Bonass, William A; Thomson, Neil H
2017-05-01
The influence of heparin and heparan sulphate (HepS) on the appearance and analysis of open promoter complex (RP o ) formation by E. coli RNA polymerase (RNAP) holoenzyme (σ 70 RNAP) on linear DNA using ex situ imaging by atomic force microscopy (AFM) has been investigated. Introducing heparin or HepS into the reaction mix significantly reduces non-specific interactions of the σ 70 RNAP and RNAP after RP o formation allowing for better interpretation of complexes shown within AFM images, particularly on DNA templates containing more than one promoter. Previous expectation was that negatively charged polysaccharides, often used as competitive inhibitors of σRNAP binding and RP o formation, would also inhibit binding of the DNA template to the mica support surface and thereby lower the imaging yield of active RNAP-DNA complexes. We found that the reverse of this was true, and that the yield of RP o formation detected by AFM, for a simple tandem gene model containing two λ PR promoters, increased. Moreover and unexpectedly, HepS was more efficient than heparin, with both of them having a dispersive effect on the sample, minimising unwanted RNAP-RNAP interactions as well as non-specific interactions between the RNAP and DNA template. The success of this method relied on the observation that E. coli RNAP has the highest affinity for the mica surface of all the molecular components. For our system, the affinity of the three constituent biopolymers to muscovite mica was RNAP>Heparin or HepS>DNA. While we observed that heparin and HepS can inhibit DNA binding to the mica, the presence of E. coli RNAP overcomes this effect allowing a greater yield of RP o s for AFM analysis. This method can be extended to other DNA binding proteins and enzymes, which have an affinity to mica higher than DNA, to improve sample preparation for AFM studies. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.
Heparan sulfate storage in the cardiac conduction system triggers atrioventricular block.
Kato, Rie; Miyahara, Hiroaki; Kawano, Tatsuya; Matsuzuka, Atsuko; Noda, Kimiko; Izumi, Tatsuro
2017-05-01
To elucidate the novel biological functions of heparan sulfate (HS) by clinic-pathologically studying a patient with paroxysmal atrioventricular (AV) block. A long-surviving male patient with Sanfilippo syndrome type A presented with paroxysmal AV block at age 33years. He then survived another 2.5years after the onset of paroxysmal AV block and pacemaker implantation. His cardiac histopathological examination at autopsy showed HS storage in the cardiac conduction system (CCS), especially in the atrioventricular node (AVN)-His bundle branches. HS storage in the CCS might trigger AV block, arising from below the AVN-His bundle branches. This is the first description to indicate that HS might be an essential constituent of life-long CCS plasticity and that its storage in the CCS results in AV block. Copyright © 2017 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.
Physicochemical hair conformation of patients with Sanfilippo disease type IIIA.
Charan, R K; Nauer, G; Wagner, U; Klabuschnig, A; Lubec, G
1986-01-01
Sanfilippo disease type IIIA is an inborn error of metabolism with a deficiency in the heparan sulfamidase. Besides severe psychomotor retardation hair changes are obligatory. Hair is found to be coarse like a brush. We applied X-ray diffraction and infrared spectroscopy to characterize the conformation of hair samples of Sanfilippo patients. In healthy subjects as well as in the affected hair samples we found the wave numbers of structural relevance 1450, 1500, 1630, 1730, the pair 2337 and 2362, the quadruplet 2850, 2870, 2917, 2930 and 3080 cm-1. Also on X-ray diffraction analysis no differences could be detected. Though morphological-macroscopically and microscopically-changes were described for Sanfilippo hair samples, we could not find any change in supramolecular structure. The physical properties of coarseness of those hair specimen seems to be due to differences in the structural assembly of hair fibres and storage of heparan sulfate.
Wang, Xin; Wang, Hua; Yang, Hao; Li, Jun; Cai, Qiqing; Shapiro, Irving M.; Risbud, Makarand V.
2015-01-01
Matrix metalloproteinase-3 (MMP-3) plays an important role in intervertebral disc degeneration, a ubiquitous condition closely linked to low back pain and disability. Elevated expression of syndecan 4, a cell surface heparan sulfate proteoglycan, actively controls disc matrix catabolism. However, the relationship between MMP-3 expression and syndecan 4 in the context of inflammatory disc disease has not been clearly defined. We investigated the mechanisms by which cytokines control MMP-3 expression in rat and human nucleus pulposus cells. Cytokine treatment increased MMP-3 expression and promoter activity. Stable silencing of syndecan 4 blocked cytokine-mediated MMP-3 expression; more important, syndecan 4 did not mediate its effects through NF-κB or mitogen-activated protein kinase (MAPK) pathways. However, treatment with MAPK and NF-κB inhibitors resulted in partial blocking of the inductive effect of cytokines on MMP-3 expression. Loss-of-function studies confirmed that NF-κB, p38α/β2/γ/δ, and extracellular signal–regulated kinase (ERK) 2, but not ERK1, contributed to cytokine-dependent induction of MMP3 promoter activity. Similarly, inhibitor treatments, lentiviral short hairpin-p65, and short hairpin-IκB kinase β significantly decreased cytokine-dependent up-regulation in MMP-3 expression. Finally, we show that transforming growth factor-β can block the up-regulation of MMP-3 induced by tumor necrosis factor (TNF)-α by counteracting the NF-κB pathway and syndecan 4 expression. Taken together, our results suggest that cooperative signaling through syndecan 4 and the TNF receptor 1–MAPK–NF-κB axis is required for TNF-α–dependent expression of MMP-3 in nucleus pulposus cells. Controlling these pathways may slow the progression of intervertebral disc degeneration and matrix catabolism. PMID:25063530
Marolla, Ana Paula Cleto; Waisberg, Jaques; Saba, Gabriela Tognini; Waisberg, Daniel Reis; Margeotto, Fernando Beani; Pinhal, Maria Aparecida da Silva
2015-01-01
ABSTRACT Objective To determine the presence of glycosaminoglycans in the extracellular matrix of connective tissue from neoplastic and non-neoplastic colorectal tissues, since it has a central role in tumor development and progression. Methods Tissue samples from neoplastic and non-neoplastic colorectal tissues were obtained from 64 operated patients who had colorectal carcinoma with no distant metastases. Expressions of heparan sulphate, chondroitin sulphate, dermatan sulphate and their fragments were analyzed by electrospray ionization mass spectrometry, with the technique for extraction and quantification of glycosaminoglycans after proteolysis and electrophoresis. The statistical analysis included mean, standard deviation, and Student’s t test. Results The glycosaminoglycans extracted from colorectal tissue showed three electrophoretic bands in agarose gel. Electrospray ionization mass spectrometry showed characteristic disaccharide fragments from glycosaminoglycans, indicating their structural characterization in the tissues analyzed. Some peaks in the electrospray ionization mass spectrometry were not characterized as fragments of sugars, indicating the presence of fragments of the protein structure of proteoglycans generated during the glycosaminoglycan purification. The average amount of chondroitin and dermatan increased in the neoplastic tissue compared to normal tissue (p=0.01). On the other hand, the average amount of heparan decreased in the neoplastic tissue compared to normal tissue (p= 0.03). Conclusion The method allowed the determination of the glycosaminoglycans structural profile in colorectal tissue from neoplastic and non-neoplastic colorectal tissue. Neoplastic tissues showed greater amounts of chondroitin sulphate and dermatan sulphate compared to non-neoplastic tissues, while heparan sulphate was decreased in neoplastic tissues. PMID:26761548
NASA Astrophysics Data System (ADS)
Agyekum, Isaac; Zong, Chengli; Boons, Geert-Jan; Amster, I. Jonathan
2017-09-01
The analysis of heparan sulfate (HS) glycosaminoglycans presents many challenges, due to the high degree of structural heterogeneity arising from their non-template biosynthesis. Complete structural elucidation of glycosaminoglycans necessitates the unambiguous assignments of sulfo modifications and the C-5 uronic acid stereochemistry. Efforts to develop tandem mass spectrometric-based methods for the structural analysis of glycosaminoglycans have focused on the assignment of sulfo positions. The present work focuses on the assignment of the C-5 stereochemistry of the uronic acid that lies closest to the reducing end. Prior work with electron-based tandem mass spectrometry methods, specifically electron detachment dissociation (EDD), have shown great promise in providing stereo-specific product ions, such as the B3 ´ -CO2, which has been found to distinguish glucuronic acid (GlcA) from iduronic acid (IdoA) in some HS tetrasaccharides. The previously observed diagnostic ions are generally not observed with 2- O-sulfo uronic acids or for more highly sulfated heparan sulfate tetrasaccharides. A recent study using electron detachment dissociation and principal component analysis revealed a series of ions that correlate with GlcA versus IdoA for a set of 2- O-sulfo HS tetrasaccharide standards. The present work comprehensively investigates the efficacy of these ions for assigning the C-5 stereochemistry of the reducing end uronic acid in 33 HS tetrasaccharides. A diagnostic ratio can be computed from the sum of the ions that correlate to GlcA to those that correlate to IdoA. [Figure not available: see fulltext.
Glycosaminoglycans of abdominal skin after massive weight loss in post-bariatric female patients.
Veiga, Daniela Francescato; Bussolaro, Rodolpho A; Kobayashi, Elsa Y; Medeiros, Valquíria P; Martins, João R M; Garcia, Elvio B; Novo, Neil F; Nader, Helena B; Ferreira, Lydia M
2011-06-01
The number of post-bariatric patients had a significant increase over the last years, and a better understanding of the consequences of massive weight loss on skin is imperative. Despite weight-loss-related changes in collagen and elastin have been reported, less is known about changes in another of the matrix components of the skin, the glycosaminoglycans. The objective of this study is to evaluate abdominal skin glycosaminoglycans concentrations and perlecan and collagen III expression in post-bariatric female patients. Skin tissue samples from the abdomen of lean (n = 19) and post-bariatric (n = 24) female patients were compared. Sulfated glycosaminoglycans and hyaluronic acid were extracted, characterized and quantified. Perlecan and collagen III expression was assessed by immunofluorescence. The major glycosaminoglycans found were dermatan sultafe and hyaluronic acid; the others were found in smaller amounts. The skin of the post-bariatric patients had lower concentrations of heparan sulfate (p = 0.002) while hyaluronic acid, dermatan sulfate, and chondroitin sulfate concentrations were similar to the lean women's skin. Post-bariatric skin showed decreased expression of perlecan and increased expression of collagen III. No correlation was found among glycosaminoglycans concentrations and age, body mass index, frequency of pregnancies, or skin types, but it was observed in higher skin heparan sulfate concentrations in post-bariatric patients who had their weights stabilized for over than 24 months (p = 0.000). Abdominal skin of post-bariatric women presented decreased heparan sulfate concentrations and perlecan expression and increased expression of collagen III.
Inhibition of Human Papillomavirus Type 16 Infection Using an RNA Aptamer.
Valencia-Reséndiz, Diana Gabriela; Palomino-Vizcaino, Giovanni; Tapia-Vieyra, Juana Virginia; Benítez-Hess, María Luisa; Leija-Montoya, Ana Gabriela; Alvarez-Salas, Luis Marat
2018-04-01
Human papillomavirus type 16 (HPV16) DNA has been found in ∼50% of cervical tumors worldwide. HPV infection starts with the binding of the virus capsid to heparan sulfate (HS) receptors exposed on the surface of epithelial basal layer keratinocytes. Previously, our group isolated a high-affinity RNA aptamer (Sc5c3) specific for HPV16 L1 virus-like particles (VLPs). In this study, we report the inhibition of HPV16 infection by Sc5c3 in a pseudovirus (PsVs) model. 293TT cells were infected by HPV16 PsVs containing the yellow fluorescent protein (YFP) as reporter gene. Incubation of HPV16 PsVs with Sc5c3 before infection resulted in a dose-dependent decrease in YFP fluorescence, suggesting infection inhibition. Aptamer degradation by RNase A restored PsVs infectivity, supporting the previous observation that Sc5c3 aptamer can inhibit infection. VLP mutants with removed HS binding sites were used in binding assays to elucidate the Sc5c3 blocking mechanism; however, no binding difference was observed between wild-type and mutant VLPs, suggesting that pseudoinfection inhibition relies on mechanisms additional to electrostatic HS binding site interaction. A DNA/RNA Sc5c3 version also inhibited HPV PsVs infection, suggesting that a modified, nuclease-resistant Sc5c3 may be used to inhibit HPV16 infection in vivo.
Poe, Amy R; Tang, Lingfeng; Wang, Bei; Li, Yun; Sapar, Maria L; Han, Chun
2017-09-19
Neurons sometimes completely fill available space in their receptive fields with evenly spaced dendrites to uniformly sample sensory or synaptic information. The mechanisms that enable neurons to sense and innervate all space in their target tissues are poorly understood. Using Drosophila somatosensory neurons as a model, we show that heparan sulfate proteoglycans (HSPGs) Dally and Syndecan on the surface of epidermal cells act as local permissive signals for the dendritic growth and maintenance of space-filling nociceptive C4da neurons, allowing them to innervate the entire skin. Using long-term time-lapse imaging with intact Drosophila larvae, we found that dendrites grow into HSPG-deficient areas but fail to stay there. HSPGs are necessary to stabilize microtubules in newly formed high-order dendrites. In contrast to C4da neurons, non-space-filling sensory neurons that develop in the same microenvironment do not rely on HSPGs for their dendritic growth. Furthermore, HSPGs do not act by transporting extracellular diffusible ligands or require leukocyte antigen-related (Lar), a receptor protein tyrosine phosphatase (RPTP) and the only known Drosophila HSPG receptor, for promoting dendritic growth of space-filling neurons. Interestingly, another RPTP, Ptp69D, promotes dendritic growth of C4da neurons in parallel to HSPGs. Together, our data reveal an HSPG-dependent pathway that specifically allows dendrites of space-filling neurons to innervate all target tissues in Drosophila .
Warren, Jonathan L; Hoxha, Eneida; Jumbo-Lucioni, Patricia; De Luca, Maria
2017-11-01
Signaling by direct cell-matrix interactions has been shown to impact the transcription, secretion, and storage of insulin in mammalian β cells. However, more research is still needed in this area. Syndecans are transmembrane heparan sulfate proteoglycans that function independently and in synergy with integrin-mediated signaling to mediate cell adhesion to the extracellular matrix. In this study, we used the model organism Drosophila melanogaster to determine whether knockdown of the Syndecan (Sdc) gene expression specifically in the insulin-producing cells (IPCs) might affect insulin-like peptide (ILP) production and secretion. IPCs of adult flies produce three ILPs (ILP2, ILP3, and ILP5), which have significant homology to mammalian insulin. We report that flies with reduced Sdc expression in the IPCs did not show any difference in the expression of ilp genes compared to controls. However, they had significantly reduced levels of the circulating ILP2 protein, higher circulating carbohydrates, and were less glucose tolerant than control flies. Finally, we found that IPCs-specific Sdc knockdown led to reduced levels of head Glucose transporter1 gene expression, extracellular signal-regulated kinase phosphorylation, and reactive oxygen species. Taken together, our findings suggest a cell autonomous role for Sdc in insulin release in D. melanogaster.
Gomes, Angélica M.; Kozlowski, Eliene O.; Pomin, Vitor H.; de Barros, Cintia Monteiro; Zaganeli, José L.; Pavão, Mauro S. G.
2010-01-01
Heparin-like glycans with diverse disaccharide composition and high anticoagulant activity have been described in several families of marine mollusks. The present work focused on the structural characterization of a new heparan sulfate (HS)-like polymer isolated from the mollusk Nodipecten nodosus (Linnaeus, 1758) and on its anticoagulant and antithrombotic properties. Total glycans were extracted from the mollusk and fractionated by ethanol precipitation. The main component (>90%) was identified as HS-like glycosaminoglycan, representing ∼4.6 mg g−1 of dry tissue. The mollusk HS resists degradation with heparinase I but is cleaved by nitrous acid. Analysis of the mollusk glycan by one-dimensional 1H, two-dimensional correlated spectroscopy, and heteronuclear single quantum coherence nuclear magnetic resonance revealed characteristic signals of glucuronic acid and glucosamine residues. Signals corresponding to anomeric protons of nonsulfated, 3- or 2-sulfated glucuronic acid as well as N-sulfated and/or 6-sulfated glucosamine were also observed. The mollusk HS has an anticoagulant activity of 36 IU mg−1, 5-fold lower than porcine heparin (180 IU mg−1), as measured by the activated partial thromboplastin time assay. It also inhibits factor Xa (IC50 = 0.835 μg ml−1) and thrombin (IC50 = 9.3 μg ml−1) in the presence of antithrombin. In vivo assays demonstrated that at the dose of 1 mg kg−1, the mollusk HS inhibited thrombus growth in photochemically injured arteries. No bleeding effect, factor XIIa-mediated kallikrein activity, or toxic effect on fibroblast cells was induced by the invertebrate HS at the antithrombotic dose. PMID:20053999
Improved recovery from limb ischaemia by delivery of an affinity-isolated heparan sulphate.
Poon, Selina; Lu, Xiaohua; Smith, Raymond A A; Ho, Pei; Bhakoo, Kishore; Nurcombe, Victor; Cool, Simon M
2018-05-18
Peripheral arterial disease is a major cause of limb loss and its prevalence is increasing worldwide. As most standard-of-care therapies yield only unsatisfactory outcomes, more options are needed. Recent cell- and molecular-based therapies that have aimed to modulate vascular endothelial growth factor-165 (VEGF 165 ) levels have not yet been approved for clinical use due to their uncertain side effects. We have previously reported a heparan sulphate (termed HS7) tuned to avidly bind VEGF 165 . Here, we investigated the ability of HS7 to promote vascular recovery in a murine hindlimb vascular ischaemia model. HS7 stabilised VEGF 165 against thermal and enzyme degradation in vitro, and isolated VEGF 165 from serum via affinity-chromatography. C57BL6 mice subjected to unilateral hindlimb ischaemia injury received daily intramuscular injections of respective treatments (n = 8) and were assessed over 3 weeks by laser Doppler perfusion, magnetic resonance angiography, histology and the regain of function. Mice receiving HS7 showed improved blood reperfusion in the footpad by day 7. In addition, they recovered hindlimb blood volume two- to fourfold faster compared to the saline group; the greatest rate of recovery was observed in the first week. Notably, 17% of HS7-treated animals recovered full hindlimb function by day 7, a number that grew to 58% and 100% by days 14 and 21, respectively. This was in contrast to only 38% in the control animals. These results highlight the potential of purified glycosaminoglycan fractions for clinical use following vascular insult, and confirm the importance of harnessing the activity of endogenous pro-healing factors generated at injury sites.
Kozel, Beth A; Ciliberto, Christopher H; Mecham, Robert P
2004-04-01
The initial steps of elastic fiber assembly were investigated using an in vitro assembly model in which purified recombinant tropoelastin (rbTE) was added to cultures of live or dead cells. The ability of tropoelastin to associate with preexisting elastic fibers or microfibrils in the extracellular matrix was then assessed by immunofluorescence microscopy using species-specific tropoelastin antibodies. Results show that rbTE can associate with elastic fiber components in the absence of live cells through a process that does not depend on crosslink formation. Time course studies show a transformation of the deposited protein from an initial globular appearance early in culture to a more fibrous structure as the matrix matures. Deposition required the C-terminal region of tropoelastin and correlated with the presence of preexisting elastic fibers or microfibrils. Association of exogenously added tropoelastin to the cellular extracellular matrix was inhibited by the addition of heparan sulfate but not chondroitin sulfate sugars. Together, these results suggest that the matrix elaborated by the cell is sufficient for the initial deposition of tropoelastin in the extracellular space and that elastin assembly may be influenced by the composition of sulfated proteoglycans in the matrix.
Viscoelastic response of a model endothelial glycocalyx
NASA Astrophysics Data System (ADS)
Nijenhuis, Nadja; Mizuno, Daisuke; Spaan, Jos A. E.; Schmidt, Christoph F.
2009-06-01
Many cells cover themselves with a multifunctional polymer coat, the pericellular matrix (PCM), to mediate mechanical interactions with the environment. A particular PCM, the endothelial glycocalyx (EG), is formed by vascular endothelial cells at their luminal side, forming a mechanical interface between the flowing blood and the endothelial cell layer. The glycosaminoglycan (GAG) hyaluronan (HA) is involved in the main functions of the EG, mechanotransduction of fluid shear stress and molecular sieving. HA, due to its length, is the only GAG in the EG or any other PCM able to form an entangled network. The mechanical functions of the EG are, however, impaired when any one of its components is removed. We here used microrheology to measure the effect of the EG constituents heparan sulfate, chondroitin sulfate, whole blood plasma and albumin on the high-bandwidth mechanical properties of a HA solution. Furthermore, we probed the effect of the hyaldherin aggrecan, a constituent of the PCM of chondrocytes, and very similar to versican (present in the PCM of various cells, and possibly in the EG). We show that components directly interacting with HA (chondroitin sulfate and aggrecan) can increase the viscoelastic shear modulus of the polymer composite.
Structure of adeno-associated virus-2 in complex with neutralizing monoclonal antibody A20
DOE Office of Scientific and Technical Information (OSTI.GOV)
McCraw, Dustin M.; O'Donnell, Jason K.; Taylor, Kenneth A.
2012-09-15
The use of adeno-associated virus (AAV) as a gene therapy vector is limited by the host neutralizing immune response. The cryo-electron microscopy (EM) structure at 8.5 A resolution is determined for a complex of AAV-2 with the Fab' fragment of monoclonal antibody (MAb) A20, the most extensively characterized AAV MAb. The binding footprint is determined through fitting the cryo-EM reconstruction with a homology model following sequencing of the variable domain, and provides a structural basis for integrating diverse prior epitope mappings. The footprint extends from the previously implicated plateau to the side of the spike, and into the conserved canyon,more » covering a larger area than anticipated. Comparison with structures of binding and non-binding serotypes indicates that recognition depends on a combination of subtle serotype-specific features. Separation of the neutralizing epitope from the heparan sulfate cell attachment site encourages attempts to develop immune-resistant vectors that can still bind to target cells.« less
Poggi, Andreina; Rossi, Cosmo; Casella, Nicola; Bruno, Cristiana; Sturiale, Luisella; Dossi, Carla; Naggi, Annamaria
2002-08-01
Heparin (H), heparan sulfate (HS), and related glycosaminoglycans can inhibit cancer cell invasion, possibly due to their ability to interact with vascular growth factors, adhesion molecules, endoglycosidases, and signaling proteins, in addition to the well-known effects on the clotting system. We evaluated the antitumor activity of a series of semisynthetic sulfaminoheparosan sulfates (SAHSs) with different degree and distribution of sulfates, obtained by chemical modifications of the E. coli K5 polysaccharide, namely type A, B, and C compounds. B16-BL6 melanoma cells (10 5 cells/mouse) were injected intravenously (i.v.) in a lateral tail vein of C57BL6 mice at a dose of 0.5 mg/ mouse together with test compounds. Tumor lung nodules were significantly reduced as compared with controls only by H (95.5 +/- 1.0% inhibition), SAHS-2 (84.2 +/- 5.0% inhibition), and SAHS-4 (91.1 +/- 4.2% inhibition), among compounds tested. SAHS-2 and SAHS-4 are type B compounds, with a sulfate/carboxylate ratio similar to that of H. A typical mammalian HS showed only 54.8% inhibition. Supersulfated low-molecular-weight heparin and heparan sulfate (ssLMWH and ssLMWHS) showed an activity similar to that of unfractionated compounds. H and SAHS-4 inhibited dose dependently B16-BL6 lung colonies, with IC-50 values of 0.05 and 0.1 mg/mouse, respectively. The relationship with ex vivo anticoagulant potency was evaluated by activated partial thromboplastin time (aPTT) on mouse plasma at different time intervals after i.v. injection (0.1 to 0.5 mg/mouse) of the compound. H showed a dose-dependent anticoagulant activity lasting up to 2 hours, whereas SAHS-4 showed a potent anticoagulant effect only at a dose of 0.5 mg/mouse. Accordingly, H but not SAHS-4 consistently inhibited B16-BL6 lung colonies when given 1 hour before tumor cells. SAHS-4 derivatives, with different size and/or affinity depleted of AT binding sites, showed an inhibitory effect on B16-BL6 melanoma similar to that of SAHS-4, suggesting that the greater antitumor effect of H was not due to AT-mediated inhibition of blood clotting. Interactions with other blood inhibitors, such as heparin cofactor II or tissue factor pathway inhibitory protein cannot be ruled out. The better effect of H may be due to persistence in the circulation and/or ability to inhibit tumor neoangiogenesis.
Proteoglycans synthesized by smooth muscle cells derived from monkey (Macaca nemestrina) aorta.
Chang, Y; Yanagishita, M; Hascall, V C; Wight, T N
1983-05-10
Smooth muscle cells derived from monkey aorta were cultured in medium with [35S]sulfate and [3H]glucosamine as labeling precursors. Proteoglycans in the medium and in 4 M guanidine HCl extracts of the cell layer were purified by DEAE-Sephacel and molecular sieve chromatography. Both preparations contained a predominant, large chondroitin sulfate proteoglycan (Kav = 0.30 on Sepharose CL-2B) with glycosaminoglycan chains of Mr approximately 43,000 average containing a ratio of 6-sulfate to 4-sulfate of approximately 2. Approximately 7 and 27% of the 3H label in this proteoglycan were present in N-linked and O-linked oligosaccharides, respectively. Reaggregation experiments indicated that a large proportion of these proteoglycans can form link protein-stabilized aggregates. The medium fraction also contained a smaller dermatan sulfate proteoglycan (Kav = 0.67 on Sepharose CL-2B) with glycosaminoglycan chains of Mr approximately 43,000 containing a ratio of 6-sulfate to 4-sulfate of about 0.5. This proteoglycan contained approximately the same percentage of N-linked oligosaccharides as the chondroitin sulfate proteoglycan, but few or no O-linked oligosaccharides. A smaller dermatan sulfate proteoglycan with a single chain was present only in the cell layer. Additionally, small amounts of heparan sulfate proteoglycans were synthesized by the cells.
Dogné, Sophie; Flamion, Bruno; Caron, Nathalie
2018-07-01
The endothelial glycocalyx (EG), which covers the apical surface of the endothelial cells and floats into the lumen of the vessels, is a key player in vascular integrity and cardiovascular homeostasis. The EG is composed of PGs (proteoglycans), glycoproteins, glycolipids, and glycosaminoglycans, in particular hyaluronan (HA). HA seems to be implicated in most of the functions described for EG such as creating a space between blood and the endothelium, controlling vessel permeability, restricting leukocyte and platelet adhesion, and allowing an appropriate endothelial response to flow variation through mechanosensing. The amount of HA in the EG may be regulated by HYAL (hyaluronidase) 1, the most active somatic hyaluronidase. HYAL1 seems enriched in endothelial cells through endocytosis from the bloodstream. The role of the other main somatic hyaluronidase, HYAL2, in the EG is uncertain. Damage to the EG, accompanied by shedding of one or more of its components, is an early sign of various pathologies including diabetes mellitus. Shedding increases the blood or plasma concentration of several EG components, such as HA, heparan sulfate, and syndecan. The plasma levels of these molecules can then be used as sensitive markers of EG degradation. This has been shown in type 1 and type 2 diabetic patients. Recent experimental studies suggest that preserving the size and amount of EG HA in the face of diabetic insults could be a useful novel therapeutic strategy to slow diabetic complications. One way to achieve this goal, as suggested by a murine model of HYAL1 deficiency, may be to inhibit the function of HYAL1. The same approach may succeed in other pathological situations involving endothelial dysfunction and EG damage. © 2018 American Heart Association, Inc.
P-selectin- and heparanase-dependent antimetastatic activity of non-anticoagulant heparins.
Hostettler, Nina; Naggi, Annamaria; Torri, Giangiacomo; Ishai-Michaeli, Riva; Casu, Benito; Vlodavsky, Israel; Borsig, Lubor
2007-11-01
Vascular cell adhesion molecules, P- and L-selectins, facilitate metastasis of cancer cells in mice by mediating interactions with platelets, endothelium, and leukocytes. Heparanase is an endoglycosidase that degrades heparan sulfate of extracellular matrix, thereby promoting tumor invasion and metastasis. Heparin is known to efficiently attenuate metastasis in different tumor models. Here we identified modified, nonanticoagulant species of heparin that specifically inhibit selectin-mediated cell-cell interactions, heparanase enzymatic activity, or both. We show that selective inhibition of selectin interactions or heparanase with specific heparin derivatives in mouse models of MC-38 colon carcinoma and B16-BL6 melanoma attenuates metastasis. Selectin-specific heparin derivatives attenuated metastasis of MC-38 carcinoma, but heparanase-specific derivatives had no effect, in accordance with the virtual absence of heparanase activity in these cells. Heparin derivatives had no further effect on metastasis in mice deficient in P- and L-selectin, indicating that selectins are the primary targets of heparin antimetastatic activity. Selectin-specific and heparanase-specific derivatives attenuated metastasis of B16-BL6 melanomas to a similar extent. When mice were injected with a derivative containing both heparanase and selectin inhibitory activity, no additional attenuation of metastasis could be observed. Thus, selectin-specific heparin derivatives efficiently attenuated metastasis of both tumor cell types whereas inhibition of heparanase led to reduction of metastasis only in tumor cells producing heparanase.
Martin, Lukas; De Santis, Rebecca; Koczera, Patrick; Simons, Nadine; Haase, Hajo; Heinbockel, Lena; Brandenburg, Klaus; Marx, Gernot; Schuerholz, Tobias
2015-01-01
Heparanase is an endo-β-glucuronidase that cleaves heparan sulfate side chains from their proteoglycans. Thereby, heparanase liberates highly potent circulating heparan sulfate-fragments (HS-fragments) and triggers the fatal and excessive inflammatory response in sepsis. As a potential anti-inflammatory agent for sepsis therapy, peptide 19-2.5 belongs to the class of synthetic anti-lipopolysaccharide peptides; however, its activity is not restricted to Gram-negative bacterial infection. We hypothesized that peptide 19-2.5 interacts with heparanase and/or HS, thereby reducing the levels of circulating HS-fragments in murine and human sepsis. Our data indicate that the treatment of septic mice with peptide 19-2.5 compared to untreated control animals lowers levels of plasma heparanase and circulating HS-fragments and reduces heparanase activity. Additionally, mRNA levels of heparanase in heart, liver, lung, kidney and spleen are downregulated in septic mice treated with peptide 19-2.5 compared to untreated control animals. In humans, plasma heparanase level and activity are elevated in septic shock. The ex vivo addition of peptide 19-2.5 to plasma of septic shock patients decreases heparanase activity but not heparanase level. Isothermal titration calorimetry revealed a strong exothermic reaction between peptide 19-2.5 and heparanase and HS-fragments. However, a saturation character has been identified only in the peptide 19-2.5 and HS interaction. In conclusion, the findings of our current study indicate that peptide 19-2.5 interacts with heparanase, which is elevated in murine and human sepsis and consecutively attenuates the generation of circulating HS-fragments in systemic inflammation. Thus, peptide 19-2.5 seems to be a potential anti-inflammatory agent in sepsis.
Can we produce heparin/heparan sulfate biomimetics using "mother-nature" as the gold standard?
Farrugia, Brooke L; Lord, Megan S; Melrose, James; Whitelock, John M
2015-03-05
Heparan sulfate (HS) and heparin are glycosaminoglycans (GAGs) that are heterogeneous in nature, not only due to differing disaccharide combinations, but also their sulfate modifications. HS is well known for its interactions with various growth factors and cytokines; and heparin for its clinical use as an anticoagulant. Due to their potential use in tissue regeneration; and the recent adverse events due to contamination of heparin; there is an increased surge to produce these GAGs on a commercial scale. The production of HS from natural sources is limited so strategies are being explored to be biomimetically produced via chemical; chemoenzymatic synthesis methods and through the recombinant expression of proteoglycans. This review details the most recent advances in the field of HS/heparin synthesis for the production of low molecular weight heparin (LMWH) and as a tool further our understanding of the interactions that occur between GAGs and growth factors and cytokines involved in tissue development and repair.
Osago, Harumi; Shibata, Tomoko; Hara, Nobumasa; Kuwata, Suguru; Kono, Michihaya; Uchio, Yuji; Tsuchiya, Mikako
2014-12-15
We developed a method using liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) with a selected reaction monitoring (SRM) mode for simultaneous quantitative analysis of glycosaminoglycans (GAGs). Using one-shot analysis with our MS/MS method, we demonstrated the simultaneous quantification of a total of 23 variously sulfated disaccharides of four GAG classes (8 chondroitin/dermatan sulfates, 1 hyaluronic acid, 12 heparan sulfates, and 2 keratan sulfates) with a sensitivity of less than 0.5 pmol within 20 min. We showed the differences in the composition of GAG classes and the sulfation patterns between porcine articular cartilage and yellow ligament. In addition to the internal disaccharides described above, some saccharides derived from the nonreducing terminal were detected simultaneously. The simultaneous quantification of both internal and nonreducing terminal saccharides could be useful to estimate the chain length of GAGs. This method would help to establish comprehensive "GAGomic" analysis of biological tissues. Copyright © 2014 Elsevier Inc. All rights reserved.
Nagy, Nandor; Barad, Csilla; Hotta, Ryo; Bhave, Sukhada; Arciero, Emily; Dora, David; Goldstein, Allan M
2018-05-08
The enteric nervous system (ENS) arises from neural crest cells that migrate, proliferate, and differentiate into enteric neurons and glia within the intestinal wall. Many extracellular matrix (ECM) components are present in the embryonic gut, but their role in regulating ENS development is largely unknown. Here, we identify heparan sulfate proteoglycan proteins, including collagen XVIII (Col18) and agrin, as important regulators of enteric neural crest-derived cell (ENCDC) development. In developing avian hindgut, Col18 is expressed at the ENCDC wavefront, while agrin expression occurs later. Both proteins are normally present around enteric ganglia, but are absent in aganglionic gut. Using chick-mouse intestinal chimeras and enteric neurospheres, we show that vagal- and sacral-derived ENCDCs from both species secrete Col18 and agrin. Whereas glia express Col18 and agrin, enteric neurons only express the latter. Functional studies demonstrate that Col18 is permissive whereas agrin is strongly inhibitory to ENCDC migration, consistent with the timing of their expression during ENS development. We conclude that ENCDCs govern their own migration by actively remodeling their microenvironment through secretion of ECM proteins. © 2018. Published by The Company of Biologists Ltd.
Recombinant Domain V of Human Perlecan Is a Bioactive Vascular Proteoglycan.
Rnjak-Kovacina, Jelena; Tang, Fengying; Lin, Xiaoting; Whitelock, John M; Lord, Megan S
2017-12-01
The C-terminal domain V of the extracellular matrix proteoglycan perlecan plays unique and often divergent roles in a number of biological processes, including angiogenesis, vascular cell interactions, wound healing, and autophagy. Recombinant forms of domain V have been proposed as therapeutic agents for the treatment of cancer, stroke, and the development of cardiovascular devices and bioartificial tissues. However, the effect of domain V appears to be related to the differences in domain V structure and function observed in different expression systems and environments and exactly how this occurs is not well understood. In this study, the sequence from amino acid 3626 to 4391 of the perlecan protein core, which includes domain V, is expressed in HEK-293 cells and purified as a secreted product from conditioned media. This recombinant domain V (rDV) is expressed as a proteoglycan decorated with heparan sulfate and chondroitin sulfate chains and supports endothelial cell interactions to the same extent as full-length perlecan. This expression system serves as an important model of recombinant proteoglycan expression, as well as a source of biologically active rDV for therapeutic applications. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Syndecan-2 regulates melanin synthesis via protein kinase C βII-mediated tyrosinase activation.
Jung, Hyejung; Chung, Heesung; Chang, Sung Eun; Choi, Sora; Han, Inn-Oc; Kang, Duk-Hee; Oh, Eok-Soo
2014-05-01
Syndecan-2, a transmembrane heparan sulfate proteoglycan that is highly expressed in melanoma cells, regulates melanoma cell functions (e.g. migration). Since melanoma is a malignant tumor of melanocytes, which largely function to synthesize melanin, we investigated the possible involvement of syndecan-2 in melanogenesis. Syndecan-2 expression was increased in human skin melanoma tissues compared with normal skin. In both mouse and human melanoma cells, siRNA-mediated knockdown of syndecan-2 was associated with reduced melanin synthesis, whereas overexpression of syndecan-2 increased melanin synthesis. Similar effects were also detected in human primary epidermal melanocytes. Syndecan-2 expression did not affect the expression of tyrosinase, a key enzyme in melanin synthesis, but instead enhanced the enzymatic activity of tyrosinase by increasing the membrane and melanosome localization of its regulator, protein kinase CβII. Furthermore, UVB caused increased syndecan-2 expression, and this up-regulation of syndecan-2 was required for UVB-induced melanin synthesis. Taken together, these data suggest that syndecan-2 regulates melanin synthesis and could be a potential therapeutic target for treating melanin-associated diseases. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Hara, Takato; Kojima, Takayuki; Matsuzaki, Hiroka; Nakamura, Takehiro; Yoshida, Eiko; Fujiwara, Yasuyuki; Yamamoto, Chika; Saito, Shinichi; Kaji, Toshiyuki
2017-02-08
Organic-inorganic hybrid molecules constitute analytical tools used in biological systems. Vascular endothelial cells synthesize and secrete proteoglycans, which are macromolecules consisting of a core protein and glycosaminoglycan side chains. Although the expression of endothelial proteoglycans is regulated by several cytokines/growth factors, there may be alternative pathways for proteoglycan synthesis aside from downstream pathways activated by these cytokines/growth factors. Here, we investigated organic-inorganic hybrid molecules to determine a variant capable of analyzing the expression of syndecan-4, a transmembrane heparan-sulfate proteoglycan, and identified 1,10-phenanthroline ( o -Phen) with or without zinc (Zn-Phen) or rhodium (Rh-Phen). Bovine aortic endothelial cells in culture were treated with these compounds, and the expression of syndecan-4 mRNA and core proteins was determined by real-time reverse transcription polymerase chain reaction and Western blot analysis, respectively. Our findings indicated that o -Phen and Zn-Phen specifically and strongly induced syndecan-4 expression in cultured vascular endothelial cells through activation of the hypoxia-inducible factor-1α/β pathway via inhibition of prolyl hydroxylase-domain-containing protein 2. These results demonstrated an alternative pathway involved in mediating induction of endothelial syndecan-4 expression and revealed organic-inorganic hybrid molecules as effective tools for analyzing biological systems.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Prince, Robin N.; Schreiter, Eric R.; Zou, Peng
2010-07-01
Heparin-binding EGF-like growth factor (HB-EGF) is a ligand for EGF receptor (EGFR) and possesses the ability to signal in juxtacrine, autocrine and/or paracrine mode, with these alternatives being governed by the degree of proteolytic release of the ligand. Although the spatial range of diffusion of released HB-EGF is restricted by binding heparan-sulfate proteoglycans (HSPGs) in the extracellular matrix and/or cellular glycocalyx, ascertaining mechanisms governing non-released HB-EGF localization is also important for understanding its effects. We have employed a new method for independently tracking the localization of the extracellular EGFlike domain of HB-EGF and the cytoplasmic C-terminus. A striking observation wasmore » the absence of the HB-EGF transmembrane proform from the leading edge of COS-7 cells in a wound-closure assay; instead, this protein localized in regions of cell-cell contact. A battery of detailed experiments found that this localization derives from a trans interaction between extracellular HSPGs and the HBEGF heparin-binding domain, and that disruption of this interaction leads to increased release of soluble ligand and a switch in cell phenotype from juxtacrine-induced growth inhibition to autocrine-induced proliferation. Our results indicate that extracellular HSPGs serve to sequester the transmembrane pro-form of HB-EGF at the point of cell-cell contact, and that this plays a role in governing the balance between juxtacrine versus autocrine and paracrine signaling.« less
Yan, Dong; Lin, Xinhua
2007-01-01
Summary Previous studies in Drosophila have shown that heparan sulfate proteoglycans (HSPGs) are involved in both breathless (btl)- and heartless (htl)-mediated FGF signaling during embryogenesis. However, the mechanism(s) by which HSPGs control Btl and Htl signaling is unknown. Here we show that dally-like (dlp, a Drosophila glypican) mutant embryos exhibit severe defects in tracheal morphogenesis and show a reduction in btl-mediated FGF signaling activity. However, htl-dependent mesodermal cell migration is not affected in dlp mutant embryos. Furthermore, expression of Dlp, but not other Drosophila HSPGs, can restore effectively the tracheal morphogenesis in dlp embryos. Rescue experiments in dlp embryos demonstrate that Dlp functions only in Bnl/FGF receiving cells in a cell-autonomous manner, but is not essential for Bnl/FGF expression cells. To further dissect the mechanism(s) of Dlp in Btl signaling, we analyzed the role of Dlp in Btl-mediated air sac tracheoblast formation in wing discs. Mosaic analysis experiments show that removal of HSPG activity in FGF-producing or other surrounding cells does not affect tracheoblasts migration, while HSPG mutant tracheoblast cells fail to receive FGF signaling. Together, our results argue strongly that HSPGs regulate Btl signaling exclusively in FGF-receiving cells as co-receptors, but are not essential for the secretion and distribution of the FGF ligand. This mechanism is distinct from HSPG functions in morphogen distribution, and is likely a general paradigm for HSPG functions in FGF signaling in Drosophila. PMID:17959166
A heparin-functionalized carbon nanotube-based affinity biosensor for dengue virus.
Wasik, Daniel; Mulchandani, Ashok; Yates, Marylynn V
2017-05-15
Dengue virus is an arthropod-borne virus transmitted primarily by Aedes mosquitos and is major cause of disease in tropical and subtropical regions. Colloquially known as Dengue Fever, infection can cause hemorrhagic disorders and death in humans and non-human primates. We report a novel electronic biosensor based on a single-walled carbon nanotube network chemiresistive transducer that is functionalized with heparin for low-cost, label-free, ultra-sensitive, and rapid detection of whole dengue virus (DENV). Heparin, an analog of the heparan sulfate proteoglycans that are receptors for dengue virus during infection of Vero cells and hepatocytes, was used for the first time in a biosensor as a biorecognition element instead of traditional antibody. Detection of DENV in viral culture supernatant has similar sensitivity as the corresponding viral titer in phosphate buffer despite the presence of growth media and Vero cell lysate. The biosensor demonstrated sensitivity within the clinically relevant range for humans and infected Aedes aegypti. It has potential application in clinical diagnosis and can improve point-of-care diagnostics of dengue infection. Copyright © 2017 Elsevier B.V. All rights reserved.
Glypican-5 stimulates rhabdomyosarcoma cell proliferation by activating Hedgehog signaling
Shi, Wen; Capurro, Mariana
2011-01-01
Glypican-5 (GPC5) is one of the six members of the glypican family. It has been previously reported that GPC5 stimulates the proliferation of rhabdomyosarcoma cells. In this study, we show that this stimulatory activity of GPC5 is a result of its ability to promote Hedgehog (Hh) signaling. We have previously shown that GPC3, another member of the glypican family, inhibits Hh signaling by competing with Patched 1 (Ptc1) for Hh binding. Furthermore, we showed that GPC3 binds to Hh through its core protein but not to Ptc1. In this paper, we demonstrate that GPC5 increases the binding of Sonic Hh to Ptc1. We also show that GPC5 binds to both Hh and Ptc1 through its glycosaminoglycan chains and that, unlike GPC3, GPC5 localizes to the primary cilia. Interestingly, we found that the heparan sulfate chains of GPC5 display a significantly higher degree of sulfation than those of GPC3. Based on these results, we propose that GPC5 stimulates Hh signaling by facilitating/stabilizing the interaction between Hh and Ptc1. PMID:21339334
Panch, Sandhya R; Szymanski, James; Savani, Bipin N; Stroncek, David F
2017-08-01
Bone marrow (BM) aspirates, mobilized peripheral blood, and umbilical cord blood (UCB) have developed as graft sources for hematopoietic stem and progenitor cells (HSPCs) for stem cell transplantation and other cellular therapeutics. Individualized techniques are necessary to enhance graft HSPC yields and cell quality from each graft source. BM aspirates yield adequate CD34 + cells but can result in relative delays in engraftment. Granulocyte colony-stimulating factor (G-CSF)-primed BM HSPCs may facilitate faster engraftment while minimizing graft-versus-host disease in certain patient subsets. The levels of circulating HSPCs are enhanced using mobilizing agents, such as G-CSF and/or plerixafor, which act via the stromal cell-derived factor 1/C-X-C chemokine receptor type 4 axis. Alternate niche pathway mediators, including very late antigen-4/vascular cell adhesion molecule-1, heparan sulfate proteoglycans, parathyroid hormone, and coagulation cascade intermediates, may offer promising alternatives for graft enhancement. UCB grafts have been expanded ex vivo with cytokines, notch-ligand, or mesenchymal stromal cells, and most studies demonstrated greater quantities of CD34 + cells ex vivo and improved short-term engraftment. No significant changes were observed in long-term repopulating potential or in patient survival. Early phase clinical trials using nicotinamide and StemReginin1 may offer improved short- and long-term repopulating ability. Breakthroughs in genome editing and stem cell reprogramming technologies may hasten the generation of pooled, third-party HSPC grafts. This review elucidates past, present, and potential future approaches to HSPC graft optimization. Published by Elsevier Inc.
Velleman, Sandra G; Clark, Daniel L; Tonniges, Jeffrey R
2018-09-01
Posthatch skeletal muscle growth requires myogenic satellite cells and the dynamic expression of cell membrane-associated proteins. The membrane associated heparan sulfate proteoglycans, syndecan-4 and glypican-1, link the satellite cell niche to the intracellular environment. Sydnecan-4 and glypican-1 are differentially expressed with age in turkey satellite cells and their over-expression impacts both satellite cell proliferation and differentiation, but their effect on satellite cells from lines with different growth potentials is not known. The objective of the current study was to determine if syndecan-4 and glypican-1 regulation of satellite cell proliferation and differentiation is affected by age and growth selection. Pectoralis major satellite cells isolated at 1 d, 7 and 16-wk of age from a Randombred Control 2 (RBC2) line and a 16-wk body weight (F) line selected from the RBC2 line turkeys were studied. Syndecan-4 and glypican-1 expression was knocked down in both lines. The F-line cells proliferated faster than RBC2 line cells regardless of age, while differentiation tended to be greater in RBC2 line cells than F-line cells at each age. Syndecan-4 knockdown decreased proliferation at 7- and 16-wk but not 1 d cells, and increased differentiation at 1 d and 7 wk but not 16 wk cells. Glypican-1 knockdown differentially affected proliferation depending on cell age, whereas differentiation was decreased for 7- and 16-wk but not 1 d cells. These data suggest syndecan-4 and glypican-1 differentially affected satellite cell function in an age-dependent manner, but had little impact on differences in proliferation and differentiation due to growth selection. Copyright © 2018. Published by Elsevier Inc.
Benavent Acero, Fernando R; Perera Negrin, Yasser; Alonso, Daniel F; Perea, Silvio E; Gomez, Daniel E; Farina, Hernán G
2014-06-02
CIGB-300 is a cyclic synthetic peptide that induces apoptosis in malignant cells, elicits antitumor activity in cancer animal models, and shows tumor reduction signs when assayed in first-in-human phase I trial in patients with cervical tumors. CIGB-300 impairs phosphorylation by casein kinase 2 through targeting the substrate's phosphoacceptor domain. CIGB-300 was linked to the cell penetrating peptide Tat to facilitate the delivery into cells. Previously, we showed that CIGB-300 had a differential antiproliferative behavior in different tumor cell lines. In this work, we studied differential antiproliferative behavior in terms of cellular uptake, intracellular transportation, and degradation in tumor cell lines with dissimilar sensitivity to CIGB-300. The internalization of CIGB-300 was studied in different malignant cell lines. We found that the cell membrane heparan sulfate proteoglycans act as main receptors for extracellular CIGB-300 uptake. The most sensitive tumor cell lines showed higher intracellular incorporation of CIGB-300 in comparison to less sensitive cell lines. Furthermore, CIGB-300 uptake is time- and concentration-dependent in all studied cell lines. It was shown that CIGB-300 has the ability to penetrate cells mainly by direct membrane translocation. However, a minor proportion of the peptide uses an energy-dependent endocytic pathway mechanism to gain access into cells. CIGB-300 is internalized and transported into cells preferentially by caveolae-mediated endocytosis. Lysosomes are involved in CIGB-300 degradation; highly sensitive cell lines showed degradation at earlier times compared to low sensitive cells. Altogether, our data suggests a mechanism of internalization, vesicular transportation, and degradation for CIGB-300 in tumor cells.
Belvedere, Raffaella; Bizzarro, Valentina; Parente, Luca; Petrella, Francesco; Petrella, Antonello
2017-07-25
Glycosaminoglycans are polysaccharides of the extracellular matrix supporting skin wound closure. Mesoglycan is a mixture of glycosaminoglycans such as chondroitin-, dermatan-, heparan-sulfate and heparin and is the main component of Prisma ® Skin, a pharmaceutical device developed by Mediolanum Farmaceutici S.p.a. Here, we show the in vitro effects of this device in the new vessels formation by endothelial cells, since angiogenesis represents a key moment in wound healing. We found a strong increase of migration and invasion rates of these cells treated with mesoglycan and Prisma ® Skin which mediate the activation of the pathway triggered by CD44 receptor. Furthermore, endothelial cells form longer capillary-like structures with a great number of branches, in the presence of the same treatments. Thus, the device, thanks to the mesoglycan, leads the cells to the Endothelial-to-Mesenchymal Transition, suggesting the switch to a fibroblast-like phenotype, as shown by immunofluorescence assays. Finally, we found that mesoglycan and Prisma ® Skin inhibit inflammatory reactions such as nitric oxide secretion and NF-κB nuclear translocation in endothelial cells and Tumor Necrosis Factor-α production by macrophages. In conclusion, based on our data, we suggest that Prisma ® Skin may be able to accelerate angiogenesis in skin wound healing, and regulate inflammation avoiding chronic, thus pathological, responses.
Vicente, Carolina Meloni; Ricci, Ritchelli; Nader, Helena Bonciani; Toma, Leny
2013-05-25
The extracellular matrix (ECM) influences the structure, viability and functions of cells and tissues. Recent evidence indicates that tumor cells and stromal cells interact through direct cell-cell contact, the production of ECM components and the secretion of growth factors. Syndecans are a family of transmembrane heparan sulfate proteoglycans that are involved in cell adhesion, motility, proliferation and differentiation. Syndecan-2 has been found to be highly expressed in colorectal cancer cell lines and appears to be critical for cancer cell behavior. We have examined the effect of stromal fibroblast-produced ECM on the production of proteoglycans by colorectal cancer cell lines. Our results showed that in a highly metastatic colorectal cancer cell line, HCT-116, syndecan-2 expression is enhanced by fibroblast ECM, while the expression of other syndecans decreased. Of the various components of the stromal ECM, fibronectin was the most important in stimulating the increase in syndecan-2 expression. The co-localization of syndecan-2 and fibronectin suggests that these two molecules are involved in the adhesion of HCT-116 cells to the ECM. Additionally, we demonstrated an increase in the expression of integrins alpha-2 and beta-1, in addition to an increase in the expression of phospho-FAK in the presence of fibroblast ECM. Furthermore, blocking syndecan-2 with a specific antibody resulted in a decrease in cell adhesion, migration, and organization of actin filaments. Overall, these results show that interactions between cancer cells and stromal ECM proteins induce significant changes in the behavior of cancer cells. In particular, a shift from the expression of anti-tumorigenic syndecans to the tumorigenic syndecan-2 may have implications in the migratory behavior of highly metastatic tumor cells.
Syndecan promotes axon regeneration by stabilizing growth cone migration
Edwards, Tyson J.; Hammarlund, Marc
2014-01-01
SUMMARY Growth cones facilitate the repair of nervous system damage by providing the driving force for axon regeneration. Using single-neuron laser axotomy and in vivo time-lapse imaging, we show that syndecan, a heparan sulfate (HS) proteoglycan, is required for growth cone function during axon regeneration in C. elegans. In the absence of syndecan, regenerating growth cones form but are unstable and collapse, decreasing the effective growth rate and impeding regrowth to target cells. We provide evidence that syndecan has two distinct functions during axon regeneration: 1) a canonical function in axon guidance that requires expression outside the nervous system and depends on HS chains, and 2) a novel intrinsic function in growth cone stabilization that is mediated by the syndecan core protein, independently of HS. Thus, syndecan is a novel regulator of a critical choke point in nervous system repair. PMID:25001284
Syndecan promotes axon regeneration by stabilizing growth cone migration.
Edwards, Tyson J; Hammarlund, Marc
2014-07-10
Growth cones facilitate the repair of nervous system damage by providing the driving force for axon regeneration. Using single-neuron laser axotomy and in vivo time-lapse imaging, we show that syndecan, a heparan sulfate (HS) proteoglycan, is required for growth cone function during axon regeneration in C. elegans. In the absence of syndecan, regenerating growth cones form but are unstable and collapse, decreasing the effective growth rate and impeding regrowth to target cells. We provide evidence that syndecan has two distinct functions during axon regeneration: (1) a canonical function in axon guidance that requires expression outside the nervous system and depends on HS chains and (2) an intrinsic function in growth cone stabilization that is mediated by the syndecan core protein, independently of HS. Thus, syndecan is a regulator of a critical choke point in nervous system repair. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.
Targeting tumor cells via EGF receptors: selective toxicity of an HBEGF-toxin fusion protein.
Chandler, L A; Sosnowski, B A; McDonald, J R; Price, J E; Aukerman, S L; Baird, A; Pierce, G F; Houston, L L
1998-09-25
Over-expression of the epidermal growth factor receptor (EGFR) is a hallmark of numerous solid tumors, thus providing a means of selectively targeting therapeutic agents. Heparin-binding epidermal growth factor (HBEGF) binds to EGFRs with high affinity and to heparan sulfate proteoglycans, resulting in increased mitogenic potential compared to other EGF family members. We have investigated the feasibility of using HBEGF to selectively deliver a cytotoxic protein into EGFR-expressing tumor cells. Recombinant fusion proteins consisting of mature human HBEGF fused to the plant ribosome-inactivating protein saporin (SAP) were expressed in Escherichia coli. Purified HBEGF-SAP chimeras inhibited protein synthesis in a cell-free assay and competed with EGF for binding to receptors on intact cells. A construct with a 22-amino-acid flexible linker (L22) between the HBEGF and SAP moieties exhibited an affinity for the EGFR that was comparable to that of HBEGF. The sensitivity to HBEGF-L22-SAP was determined for a variety of human tumor cell lines, including the 60 cell lines comprising the National Cancer Institute Anticancer Drug Screen. HBEGF-L22-SAP was cytotoxic in vitro to a variety of EGFR-bearing cell lines and inhibited growth of EGFR-over-expressing human breast carcinoma cells in vivo. In contrast, the fusion protein had no effect on small-cell lung carcinoma cells, which are EGFR-deficient. Our results demonstrate that fusion proteins composed of HBEGF and SAP exhibit targeting specificity and cytotoxicity that may be of therapeutic value in treating a variety of EGFR-bearing malignancies.
Kaur, Upninder; Khurana, Sumeeta; Saikia, Uma Nahar; Dubey, M L
2013-11-01
Entamoeba histolytica infection is associated with considerable morbidity and mortality in the form of intestinal and extraintestinal amoebiasis. No vaccine is yet available for amoebiasis. Heparan Sulphate Binding Proteins (HSBPs) from E. histolytica were evaluated for immunogenicity and protective efficacy in a Guinea pig model. Animals were immunized subcutaneously with 30μg of HSBP by three weekly inoculations. The immunogenicity of HSBP was determined by antibody response (IgG, IgM and IgA), splenocyte proliferation assay and in vitro direct amoebicidal assay with splenic lymphocytes and monocytes from vaccinated and control animals. The efficacy of the vaccine was evaluated by challenge infection to vaccinated and control animals by intra-caecal inoculation of E. histolytica trophozoites and comparing gross and histopathological findings in caeca of these animals. HSBP was found to induce specific anti-amoebic response as seen by specific antibody production and direct amoebicidal activity of splenocytes. The vaccine also showed partial protection against challenge infection in vaccinated animals as shown by mild/absent lesions and histopathological findings. Copyright © 2013 Elsevier Inc. All rights reserved.
Quantification of a Non-conventional Protein Secretion: The Low-Molecular-Weight FGF-2 Example.
Arcondéguy, Tania; Touriol, Christian; Lacazette, Eric
2016-01-01
Quantification of secreted factors is most often measured with enzyme-linked immunosorbent assay (ELISA), Western Blot, or more recently with antibody arrays. However, some of these, like low-molecular-weight fibroblast growth factor-2 (LMW FGF-2; the 18 kDa form), exemplify a set of secreted but almost non-diffusible molecular actors. It has been proposed that phosphorylated FGF-2 is secreted via a non-vesicular mechanism and that heparan sulfate proteoglycans function as extracellular reservoir but also as actors for its secretion. Heparan sulfate is a linear sulfated polysaccharide present on proteoglycans found in the extracellular matrix or anchored in the plasma membrane (syndecan). Moreover the LMW FGF-2 secretion appears to be activated upon FGF-1 treatment. In order to estimate quantification of such factor export across the plasma membrane, technical approaches are presented (evaluation of LMW FGF-2: (1) secretion, (2) extracellular matrix reservoir, and (3) secretion modulation by surrounding factors) and the importance of such procedures in the comprehension of the biology of these growth factors is underlined.
Sundararajan, Lakshmi; Norris, Megan L; Lundquist, Erik A
2015-05-28
The Q neuroblasts in Caenorhabditis elegans display left-right asymmetry in their migration, with QR and descendants on the right migrating anteriorly, and QL and descendants on the left migrating posteriorly. Initial QR and QL migration is controlled by the transmembrane receptors UNC-40/DCC, PTP-3/LAR, and the Fat-like cadherin CDH-4. After initial migration, QL responds to an EGL-20/Wnt signal that drives continued posterior migration by activating MAB-5/Hox activity in QL but not QR. QR expresses the transmembrane protein MIG-13, which is repressed by MAB-5 in QL and which drives anterior migration of QR descendants. A screen for new Q descendant AQR and PQR migration mutations identified mig-13 as well as hse-5, the gene encoding the glucuronyl C5-epimerase enzyme, which catalyzes epimerization of glucuronic acid to iduronic acid in the heparan sulfate side chains of heparan sulfate proteoglycans (HSPGs). Of five C. elegans HSPGs, we found that only SDN-1/Syndecan affected Q migrations. sdn-1 mutants showed QR descendant AQR anterior migration defects, and weaker QL descendant PQR migration defects. hse-5 affected initial Q migration, whereas sdn-1 did not. sdn-1 and hse-5 acted redundantly in AQR and PQR migration, but not initial Q migration, suggesting the involvement of other HSPGs in Q migration. Cell-specific expression studies indicated that SDN-1 can act in QR to promote anterior migration. Genetic interactions between sdn-1, mig-13, and mab-5 suggest that MIG-13 and SDN-1 act in parallel to promote anterior AQR migration and that SDN-1 also controls posterior migration. Together, our results indicate previously unappreciated complexity in the role of multiple signaling pathways and inherent left-right asymmetry in the control of Q neuroblast descendant migration. Copyright © 2015 Sundararajan et al.
Sundararajan, Lakshmi; Norris, Megan L.; Lundquist, Erik A.
2015-01-01
The Q neuroblasts in Caenorhabditis elegans display left-right asymmetry in their migration, with QR and descendants on the right migrating anteriorly, and QL and descendants on the left migrating posteriorly. Initial QR and QL migration is controlled by the transmembrane receptors UNC-40/DCC, PTP-3/LAR, and the Fat-like cadherin CDH-4. After initial migration, QL responds to an EGL-20/Wnt signal that drives continued posterior migration by activating MAB-5/Hox activity in QL but not QR. QR expresses the transmembrane protein MIG-13, which is repressed by MAB-5 in QL and which drives anterior migration of QR descendants. A screen for new Q descendant AQR and PQR migration mutations identified mig-13 as well as hse-5, the gene encoding the glucuronyl C5-epimerase enzyme, which catalyzes epimerization of glucuronic acid to iduronic acid in the heparan sulfate side chains of heparan sulfate proteoglycans (HSPGs). Of five C. elegans HSPGs, we found that only SDN-1/Syndecan affected Q migrations. sdn-1 mutants showed QR descendant AQR anterior migration defects, and weaker QL descendant PQR migration defects. hse-5 affected initial Q migration, whereas sdn-1 did not. sdn-1 and hse-5 acted redundantly in AQR and PQR migration, but not initial Q migration, suggesting the involvement of other HSPGs in Q migration. Cell-specific expression studies indicated that SDN-1 can act in QR to promote anterior migration. Genetic interactions between sdn-1, mig-13, and mab-5 suggest that MIG-13 and SDN-1 act in parallel to promote anterior AQR migration and that SDN-1 also controls posterior migration. Together, our results indicate previously unappreciated complexity in the role of multiple signaling pathways and inherent left-right asymmetry in the control of Q neuroblast descendant migration. PMID:26022293
Kibler, C; Schermutzki, F; Waller, H D; Timpl, R; Müller, C A; Klein, G
1998-06-01
Multiple myeloma represents a human B cell malignancy which is characterized by a predominant localization of the malignant cell clone within the bone marrow. With the exception of the terminal stage of the disease the myeloma tumor cells do not circulate in the peripheral blood. The bone marrow microenvironment is believed to play an important role in homing, proliferation and terminal differentiation of myeloma cells. Here we have studied the expression of several extracellular matrix (ECM) molecules in the bone marrow of multiple myeloma patients and analyzed their adhesive capacities with four different human myeloma-derived cell lines. All ECM molecules analyzed (tenascin, laminin, fibronectin, collagen types I, III, V and VI) could be detected in bone marrow cryostat sections of multiple myeloma patients. Adhesion assays showed that only laminin, the microfibrillar collagen type VI and fibronectin were strong adhesive components for the myeloma cell lines U266, IM-9, OPM-2 and NCI-H929. Tenascin and collagen type I were only weak adhesive substrates for these myeloma cells. Adhesion to laminin and fibronectin was beta 1-integrin-mediated since addition of anti-beta 1-integrin antibodies could inhibit the binding of the four different cell types to both matrix molecules. In contrast, integrins do not seem to be involved in binding of the myeloma cells to collagen type VI. Instead, inhibition of binding by heparin suggested that membrane-bound heparan sulfate proteoglycans are responsible ligands for binding to collagen type VI. Adhesion assays with several B-cell lines resembling earlier differentiation stages revealed only weak interactions with tenascin and no interactions with collagen type VI, laminin or fibronectin. In summary, the interactions of human myeloma cells with the extracellular matrix may explain the specific retention of the plasma cells within the bone marrow.
Zhao, Guoying; Karageorgos, Litsa; Hutchinson, Rhonda G; Hopwood, John J; Hemsley, Kim
2010-05-01
Mucopolysaccharidosis type IIIA (MPS IIIA) is a lysosomal storage disorder (LSD) in which an absence of sulfamidase results in incomplete degradation and subsequent accumulation of its substrate, heparan sulfate. Most neurodegenerative LSD remain untreatable. However, therapy options, such as gene, enzyme end cell therapy, are under investigation. Previously, we have constructed an embryonic stem (ES) cell line (NS21) that over-expresses human sulphamidase as a potential treatment for murine MPS IIIA. In the present study the sulfatase-modifying factor I (SUMF1) and enhanced green fluorescence protein (eGFP) genes were co-introduced under a cytomegalovirus (CMV) promoter into NS21 cells, to enhance further sulfamidase activity and provide a marker for in vivo cell tracking, respectively. eGFP was also introduced under the control of the human elongation factor-1alpha (hEF-1alpha) promoter to compare the stability of transgene expression. During differentiation of ES cells into glial precursors, SUMF1 was down-regulated and was hardly detectable by day 18 of differentiation. Likewise, eGFP expression was heterogeneous and highly unstable. Use of a human EF-1alpha promoter resulted in more homogeneous eGFP expression, with approximately 50% of cells eGFP positive following differentiation into glial precursors. Compared with NS21 cells, the outgrowth of eGFP-expressing cells was not as confluent when differentiated into glial precursors. Our data suggest that SUMF1 enhances sulfamidase activity in ES cells, hEF-1alpha is a stronger promoter than CMV for ES cells and over-expression of eGFP may affect cell growth and contribute to unstable gene expression.
λ-Carrageenan P32 Is a Potent Inhibitor of Rabies Virus Infection
Luo, Zhaochen; Tian, Dayong; Zhou, Ming; Xiao, Wenjie; Zhang, Yachun; Li, Mingming; Sui, Baokun; Wang, Wei; Guan, Huashi; Chen, Huanchun; Fu, Zhen F.; Zhao, Ling
2015-01-01
Rabies, caused by rabies virus (RABV), is an acute, fatal encephalitic disease that affects many warm-blooded mammals. Currently, post-exposure prophylaxis regimens are effective for most rabies cases, but once the clinical signs of the disease appear, current treatment options become ineffective. Carrageenan has been reported as a potent inhibitor of many viruses. In this study, the λ-carrageenan (λ-CG) P32 was investigated for its potential role in inhibiting RABV infection. Our results show that P32 specifically inhibits the replication of several RABV strains but not vesicular stomatitis virus in multiple cell lines and shows low cytotoxicity. P32 mainly abrogated viral replication during the early stage of the post-adsorption period. Further studies demonstrated that P32 could affect not only viral internalization but also viral uncoating by blocking cell fusion mediated by RABV glycoprotein. Moreover, P32 can fully inhibit RABV infection in vitro during the post-adsorption period, whereas heparin and heparan sulfate, which possess similar structures to P32, showed significant but not complete inhibition of RABV infectivity. Collectively, our results indicate that λ-CG P32 is a promising agent that can inhibit RABV infection mainly by inhibiting viral internalization and glycoprotein-mediated cell fusion and can be used for the development of novel anti-RABV drugs. PMID:26465753
Motoneurons secrete angiogenin to induce RNA cleavage in astroglia.
Skorupa, Alexandra; King, Matthew A; Aparicio, Isabela M; Dussmann, Heiko; Coughlan, Karen; Breen, Bridget; Kieran, Dairin; Concannon, Caoimhin G; Marin, Philippe; Prehn, Jochen H M
2012-04-11
Amyotrophic lateral sclerosis (ALS) is an incurable neurodegenerative disorder affecting motoneurons. Mutations in angiogenin, encoding a member of the pancreatic RNase A superfamily, segregate with ALS. We previously demonstrated that angiogenin administration shows promise as a neuroprotective therapeutic in studies using transgenic ALS mice and primary motoneuron cultures. Its mechanism of action and target cells in the spinal cord, however, are largely unknown. Using mixed motoneuron cultures, motoneuron-like NSC34 cells, and primary astroglia cultures as model systems, we here demonstrate that angiogenin is a neuronally secreted factor that is endocytosed by astroglia and mediates neuroprotection in paracrine. We show that wild-type angiogenin acts unidirectionally to induce RNA cleavage in astroglia, while the ALS-associated K40I mutant is also secreted and endocytosed, but fails to induce RNA cleavage. Angiogenin uptake into astroglia requires heparan sulfate proteoglycans, and engages clathrin-mediated endocytosis. We show that this uptake mechanism exists for mouse and human angiogenin, and delivers a functional RNase output. Moreover, we identify syndecan 4 as the angiogenin receptor mediating the selective uptake of angiogenin into astroglia. Our data provide new insights into the paracrine activities of angiogenin in the nervous system, and further highlight the critical role of non-neuronal cells in the pathogenesis of ALS.
Heparanase Localization during Palatogenesis in Mice
Hirata, Azumi; Katayama, Kentaro; Tsuji, Takehito; Natsume, Nagato; Sugahara, Toshio; Koga, Yuichi; Otsuki, Yoshinori; Nakamura, Hiroaki
2013-01-01
Palatogenesis is directed by epithelial-mesenchymal interactions and results partly from remodeling of the extracellular matrix (ECM) of the palatal shelves. Here, we assessed heparanase distribution in developing mouse palates. No heparanase was observed in the vertically oriented palatal shelves in early stages of palate formation. As palate formation progressed, the palatal shelves were reorganized and arranged horizontally above the tongue, and heparanase localized to the epithelial cells of these shelves. When the palatal bilateral shelves first made contact, the heparanase localized to epithelial cells at the tips of shelves. Later in fusing palatal shelves, the cells of the medial epithelial seam (MES) were labeled with intense heparanase signal. In contrast, the basement membrane heparan sulfate (HS) was scarcely observed in the palatal shelves in contact. Moreover, perlecan labeling was sparse in the basement membrane of the MES, on which laminin and type IV collagen were observed. Moreover, we assessed the distribution of matrix metalloproteinase- (MMP-) 9, MMP-2, and MMP-3 in developing mouse palates and these MMPs were observed in the MES. Our findings indicated that heparanase was important for palate formation because it mediated degradation of the ECM of palatal shelves. Heparanase may, in concert with other proteases, participate in the regression of the MES. PMID:23509775
Binding affinities of NKG2D and CD94 to sialyl Lewis X-expressing N-glycans and heparin.
Higai, Koji; Suzuki, Chiho; Imaizumi, Yuzo; Xin, Xin; Azuma, Yutaro; Matsumoto, Kojiro
2011-01-01
Lectin-like receptors natural killer group 2D (NKG2D) and CD94 on natural killer (NK) cells bind to α2,3-NeuAc-containing N-glycans and heparin/heparan sulfate (HS). Using recombinant glutathione S-transferase-fused extracellular lectin-like domains of NKG2D (rGST-NKG2Dlec) and CD94 (rGST-CD94lec), we evaluated their binding affinities (K(d)) to high sialyl Lewis X (sLeX)-expressing transferrin secreted by HepG2 cells (HepTf) and heparin-conjugated bovine serum albumin (Heparin-BSA), using quartz crystal microbalance (QCM) and enzyme immunoassay (EIA) microplate methods. K(d) values obtained by linear reciprocal plots revealed good coincidence between the two methods. K(d) values of rGST-NKG2Dlec obtained by QCM and EIA, respectively, were 1.19 and 1.11 µM for heparin-BSA >0.30 and 0.20 µM for HepTf, while those of rGST-CD94lec were 1.31 and 1.45 µM for HepTf >0.37 and 0.36 µM for heparin-BSA. These results suggested that these glycans can interact with NKG2D and CD94 to modulate NK cell-dependent cytotoxicity.
Ellinwood, N Matthew; Ausseil, Jérôme; Desmaris, Nathalie; Bigou, Stéphanie; Liu, Song; Jens, Jackie K; Snella, Elizabeth M; Mohammed, Eman E A; Thomson, Christopher B; Raoul, Sylvie; Joussemet, Béatrice; Roux, Françoise; Chérel, Yan; Lajat, Yaouen; Piraud, Monique; Benchaouir, Rachid; Hermening, Stephan; Petry, Harald; Froissart, Roseline; Tardieu, Marc; Ciron, Carine; Moullier, Philippe; Parkes, Jennifer; Kline, Karen L; Maire, Irène; Vanier, Marie-Thérèse; Heard, Jean-Michel; Colle, Marie-Anne
2011-02-01
Recent trials in patients with neurodegenerative diseases documented the safety of gene therapy based on adeno-associated virus (AAV) vectors deposited into the brain. Inborn errors of the metabolism are the most frequent causes of neurodegeneration in pre-adulthood. In Sanfilippo syndrome, a lysosomal storage disease in which heparan sulfate oligosaccharides accumulate, the onset of clinical manifestation is before 5 years. Studies in the mouse model showed that gene therapy providing the missing enzyme α-N-acetyl-glucosaminidase to brain cells prevents neurodegeneration and improves behavior. We now document safety and efficacy in affected dogs. Animals received eight deposits of a serotype 5 AAV vector, including vector prepared in insect Sf9 cells. As shown previously in dogs with the closely related Hurler syndrome, immunosuppression was necessary to prevent neuroinflammation and elimination of transduced cells. In immunosuppressed dogs, vector was efficiently delivered throughout the brain, induced α-N-acetyl-glucosaminidase production, cleared stored compounds and storage lesions. The suitability of the procedure for clinical application was further assessed in Hurler dogs, providing information on reproducibility, tolerance, appropriate vector type and dosage, and optimal age for treatment in a total number of 25 treated dogs. Results strongly support projects of human trials aimed at assessing this treatment in Sanfilippo syndrome.
Nagao, Ryan J; Xu, Jin; Luo, Ping; Xue, Jun; Wang, Yi; Kotha, Surya; Zeng, Wen; Fu, Xiaoyun; Himmelfarb, Jonathan; Zheng, Ying
2016-10-01
The kidney peritubular microvasculature is highly susceptible to injury from drugs and toxins, often resulting in acute kidney injury and progressive chronic kidney disease. Little is known about the process of injury and regeneration of human kidney microvasculature, resulting from the lack of appropriate kidney microvascular models that can incorporate the proper cells, extracellular matrices (ECMs), and architectures needed to understand the response and contribution of individual vascular components in these processes. In this study, we present methods to recreate the human kidney ECM (kECM) microenvironment by fabricating kECM hydrogels derived from decellularized human kidney cortex. The majority of native matrix proteins, such as collagen-IV, laminin, and heparan sulfate proteoglycan, and their isoforms were preserved in similar proportions as found in normal kidneys. Human kidney peritubular microvascular endothelial cells (HKMECs) became more quiescent when cultured on this kECM gel compared with culture on collagen-I-assessed using phenotypic, genotypic, and functional assays; whereas human umbilical vein endothelial cells became stimulated on kECM gels. We demonstrate for the first time that human kidney cortex can form a hydrogel suitable for use in flow-directed microphysiological systems. Our findings strongly suggest that selecting the proper ECM is a critical consideration in the development of vascularized organs on a chip and carries important implications for tissue engineering of all vascularized organs.
Rohloff, J; Zinke, J; Schoppmeyer, K; Tannapfel, A; Witzigmann, H; Mössner, J; Wittekind, C; Caca, K
2002-01-01
Pancreatic ductal adenocarcinoma has a median survival of less than 6 months from diagnosis. This is due to the difficulty in early diagnosis, the aggressive biological behaviour of the tumour and a lack of effective therapies for advanced disease. Mammalian heparanase is a heparan-sulphate proteoglycan cleaving enzyme. It helps to degrade the extracellular matrix and basement membranes and is involved in angiogenesis. Degradation of extracellular matrix and basement membranes as well as angiogenesis are key conditions for tumour cell spreading. Therefore, we have analysed the expression of heparanase in human pancreatic cancer tissue and cell lines. Heparanase is expressed in cell lines derived from primary tumours as well as from metastatic sites. By immunohistochemical analysis, it is preferentially expressed at the invading edge of a tumour at both metastatic and primary tumour sites. There is a trend towards heparanase expression in metastasising tumours as compared to locally growing tumours. Postoperative survival correlates inversely with heparanase expression of the tumour reflected by a median survival of 34 and 17 month for heparanase negative and positive tumours, respectively. Our results suggest, that heparanase promotes cancer cell invasion in pancreatic carcinoma and could be used as a prognostic indicator for postoperative survival of patients. British Journal of Cancer (2002) 86, 1270–1275. DOI: 10.1038/sj/bjc/6600232 www.bjcancer.com © 2002 Cancer Research UK PMID:11953884
Crystal Structure of the Frizzled-Like Cysteine-Rich Domain of the Receptor Tyrosine Kinase MuSK
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stiegler, A.; Burden, S; Hubbard, S
Muscle-specific kinase (MuSK) is an essential receptor tyrosine kinase for the establishment and maintenance of the neuromuscular junction (NMJ). Activation of MuSK by agrin, a neuronally derived heparan-sulfate proteoglycan, and LRP4 (low-density lipoprotein receptor-related protein-4), the agrin receptor, leads to clustering of acetylcholine receptors on the postsynaptic side of the NMJ. The ectodomain of MuSK comprises three immunoglobulin-like domains and a cysteine-rich domain (Fz-CRD) related to those in Frizzled proteins, the receptors for Wnts. Here, we report the crystal structure of the MuSK Fz-CRD at 2.1 {angstrom} resolution. The structure reveals a five-disulfide-bridged domain similar to CRDs of Frizzled proteinsmore » but with a divergent C-terminal region. An asymmetric dimer present in the crystal structure implicates surface hydrophobic residues that may function in homotypic or heterotypic interactions to mediate co-clustering of MuSK, rapsyn, and acetylcholine receptors at the NMJ.« less
Warren, Curtis R.; Grindel, Brian J.; Francis, Lewis; Carson, Daniel D.; Farach-Carson, Mary C.
2014-01-01
Perlecan/HSPG2, a heparan sulfate proteoglycan typically found at tissue borders including those separating epithelia and connective tissue, increases near sites of invasion of primary prostatic tumors as previously shown for other proteins involved in desmoplastic tissue reaction. Studies of prostate cancer cells and stromal cells from both prostate and bone, the major site for prostate cancer metastasis, showed that cancer cells and a subset of stromal cells increased production of perlecan in response to cytokines present in the tumor microenvironment. In silico analysis of the HSPG2 promoter revealed two conserved NFκB binding sites, in addition to the previously reported SMAD3 binding sites. By systematically transfecting cells with a variety of reporter constructs including sequences up to 2.6 kb from the start site of transcription, we identified an active cis element in the distal region of the HSPG2 promoter, and showed that it functions in regulating transcription of HSPG2. Treatment with TNF-α and/or TGFβ1 identified TNF-α as a major cytokine regulator of perlecan production. TNF-α treatment also triggered p65 nuclear translocation and binding to the HSPG2 regulatory region in stromal cells and cancer cells. In addition to stromal induction of perlecan production in the prostate, we identified a matrix-secreting bone marrow stromal cell type that may represent the source for increases in perlecan in the metastatic bone marrow environment. These studies implicate perlecan in cytokine-mediated, innate tissue responses to cancer cell invasion, a process we suggest reflects a modified wound healing tissue response co-opted by prostate cancer cells. PMID:24700612
Pizarro-Cerdá, Javier; Sousa, Sandra; Cossart, Pascale
2004-02-01
Deciphering how Listeria monocytogenes exploits the host cell machinery to invade mammalian cells during infection is a key issue for the understanding how this food-borne pathogen causes a pleiotropic disease ranging from gastro-enteritis to meningitis and abortions. Using multidisciplinary approaches, essentially combining bacterial genetics and cell biology, we have identified two bacterial proteins critical for entry into target cells, InlA and InlB. Their cellular ligands have been also identified: InlA interacts with the adhesion molecule E-cadherin, while InlB interacts with the receptor for the globular head of the complement factor C1q (gC1q-R), with the hepatocyte growth factor receptor (c-Met) and with glycosaminoglycans (including heparan sulphate). The dynamic interaction between these cellular receptors and the actin cytoskeleton is currently under investigation. Several intracellular molecules have been recognized as key effectors for Listeria entry into target cells, including catenins (implicated in the connection of E-cadherin to actin) and the actin depolymerising factor/cofilin (involved in the rearrangement of the cytoskeleton in the InlB-dependent internalisation pathway). At the organism level, species specificity has been discovered concerning the interaction between InlA and E-cadherin, leading to the generation of transgenic mice expressing the human E-cadherin, in which the critical role of InlA in the crossing of the intestinal barrier has been clearly determined. Listeria appears as an instrumental model for addressing critical questions concerning both the complex process of bacterial pathogenesis and also fundamental molecular processes, such as phagocytosis.
Pizarro-Cerdá, Javier; Sousa, Sandra; Cossart, Pascale
2004-06-01
Deciphering how Listeria monocytogenes exploits the host cell machinery to invade mammalian cells during infection isa key issue for the understanding how this food-borne pathogen causes a pleiotropic disease ranging from gastro-enteritis to meningitis and abortions. Using multidisciplinary approaches, essentially combining bacterial genetics and cell biology, we have identified two bacterial proteins critical for entry into target cells, InlA and InlB. Their cellular ligands have been also identified: InlA interacts with the adhesion molecule E-cadherin, while InlB interacts with the receptor for the globular head of the complement factor Clq (gClq-R), with the hepatocyte growth factor receptor (c-Met) and with glycosaminoglycans(including heparan sulphate). The dynamic interaction between these cellular receptors and the actin cytoskeleton is currently under investigation. Several intracellular molecules have been recognized as key effectors for Listeria entry into target cells,including catenins (implicated in the connection of E-cadherin to actin) and the actin depolymerising factor/cofilin (involved in the rearrangement of the cytoskeleton in the InlB-dependent internalisation pathway). At the organism level, species specificity has been discovered concerning the interaction between InlA and E-cadherin, leading to the generation of transgenic mice expressing the human E-cadherin, in which the critical role of InlA in the crossing of the intestinal barrier has been clearly determined. Listeria appears as an instrumental model for addressing critical questions concerning both the complex process of bacterial pathogenesis and also fundamental molecular processes, such as phagocytosis.
Bologna-Molina, R; Mikami, T; Pereira-Prado, V; Tapia-Repetto, G; Pires, F R; Carlos, R; Mosqueda-Taylor, A
2018-03-01
Primordial odontogenic tumor (POT) is composed of variably cellular myxoid connective tissue, surrounded by cuboidal to columnar odontogenic epithelium resembling the inner epithelium of the enamel organ, which often invaginates into the underlying connective tissue. The tumor is delimited at least partially by a thin fibrous capsule. It derives from the early stages of tooth development. Syndecan-1 is a heparan sulfate proteoglycan that has a physiological role in several cellular functions, including maintenance of the epithelial architecture, cell-to-cell adhesion and interaction of cells with extracellular matrix, and with diverse growth factors, stimulating cell proliferation. Ki-67 is considered the gold standard as a cell proliferation marker. The aim of this study was to examine the expression of Syndecan-1 and Ki-67 proliferation index in POT and normal tooth germs to better understand the biological behavior of this tumor. Results showed that Syndecan-1 was more intensely expressed in subepithelial mesenchymal areas of POT, in a pattern that resembles the early stages of tooth development. The cell proliferation index (4.1%) suggests that POT is a slow growing tumor. Syndecan-1 expression in tooth germs in late cap and early bell stages was similar to POT, showing immunopositivity in subepithelial mesenchymal condensed areas. The immunohistochemical findings showed a pattern in which the population of subepithelial mesenchymal cells exhibited greater proliferative activity than the central portion of the dental papilla. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd. All rights reserved.
Lintern, Katherine B; Guidato, Sonia; Rowe, Alison; Saldanha, José W; Itasaki, Nobue
2009-08-21
Cross-talk of BMP and Wnt signaling pathways has been implicated in many aspects of biological events during embryogenesis and in adulthood. A secreted protein Wise and its orthologs (Sostdc1, USAG-1, and Ectodin) have been shown to modulate Wnt signaling and also inhibit BMP signals. Modulation of Wnt signaling activity by Wise is brought about by an interaction with the Wnt co-receptor LRP6, whereas BMP inhibition is by binding to BMP ligands. Here we have investigated the mode of action of Wise on Wnt and BMP signals. It was found that Wise binds LRP6 through one of three loops formed by the cystine knot. The Wise deletion construct lacking the LRP6-interacting loop domain nevertheless binds BMP4 and inhibits BMP signals. Moreover, BMP4 does not interfere with Wise-LRP6 binding, suggesting separate domains for the physical interaction. Functional assays also show that the ability of Wise to block Wnt1 activity through LRP6 is not impeded by BMP4. In contrast, the ability of Wise to inhibit BMP4 is prevented by additional LRP6, implying a preference of Wise in binding LRP6 over BMP4. In addition to the interaction of Wise with BMP4 and LRP6, the molecular characteristics of Wise, such as glycosylation and association with heparan sulfate proteoglycans on the cell surface, are suggested. This study helps to understand the multiple functions of Wise at the molecular level and suggests a possible role for Wise in balancing Wnt and BMP signals.
Cerqueira, Carla; Samperio Ventayol, Pilar; Vogeley, Christian
2015-01-01
ABSTRACT The entry of human papillomaviruses into host cells is a complex process. It involves conformational changes at the cell surface, receptor switching, internalization by a novel endocytic mechanism, uncoating in endosomes, trafficking of a subviral complex to the Golgi complex, and nuclear entry during mitosis. Here, we addressed how the stabilizing contacts in the capsid of human papillomavirus 16 (HPV16) may be reversed to allow uncoating of the viral genome. Using biochemical and cell-biological analyses, we determined that the major capsid protein L1 underwent proteolytic cleavage during entry. In addition to a dispensable cathepsin-mediated proteolysis that occurred likely after removal of capsomers from the subviral complex in endosomes, at least two further proteolytic cleavages of L1 were observed, one of which was independent of the low-pH environment of endosomes. This cleavage occurred extracellularly. Further analysis showed that the responsible protease was the secreted trypsin-like serine protease kallikrein-8 (KLK8) involved in epidermal homeostasis and wound healing. Required for infection, the cleavage was facilitated by prior interaction of viral particles with heparan sulfate proteoglycans. KLK8-mediated cleavage was crucial for further conformational changes exposing an important epitope of the minor capsid protein L2. Occurring independently of cyclophilins and of furin that mediate L2 exposure, KLK8-mediated cleavage of L1 likely facilitated access to L2, located in the capsid lumen, and potentially uncoating. Since HPV6 and HPV18 also required KLK8 for entry, we propose that the KLK8-dependent entry step is conserved. IMPORTANCE Our analysis of the proteolytic processing of incoming HPV16, an etiological agent of cervical cancer, demonstrated that the capsid is cleaved extracellularly by a serine protease active during wound healing and that this cleavage was crucial for infection. The cleavage of L1 is one of at least four structural alterations that prime the virus extracellularly for receptor switching, internalization, and possibly uncoating. This step was also important for HPV6 and HPV18, which may suggest that it is conserved among the papillomaviruses. This study advances the understanding of how HPV16 initially infects cells, strengthens the notion that wounding facilitates infection of epidermal tissue, and may help the development of antiviral measures. PMID:25926655
Polyvalent 2D Entry Inhibitors for Pseudorabies and African Swine Fever Virus.
Ziem, Benjamin; Rahn, Jessica; Donskyi, Ievgen; Silberreis, Kim; Cuellar, Luis; Dernedde, Jens; Keil, Günther; Mettenleiter, Thomas C; Haag, Rainer
2017-06-01
African swine fever virus (ASFV) is one of the most dangerous viruses for pigs and is endemic in Africa but recently also spread into the Russian Federation and the Eastern border of the EU. So far there is no vaccine or antiviral drug available to curtail the infection. Thus, control strategies based on novel inhibitors are urgently needed. Another highly relevant virus infection in pigs is Aujeszky's disease caused by the alphaherpesvirus pseudorabies virus (PrV). This article reports the synthesis and biological evaluation of novel extracellular matrix-inspired entry inhibitors based on polyglycerol sulfate-functionalized graphene sheets. The developed 2D architectures bind enveloped viruses during the adhesion process and thereby exhibit strong inhibitory effects, which are equal or better than the common standards enrofloxacin and heparin as demonstrated for ASFV and PrV. Overall, the developed polyvalent 2D entry inhibitors are nontoxic and efficient nanoarchitectures, which interact with various types of enveloped viruses. Therefore they prevent viral adhesion to the host cell and especially target viruses that rely on a heparan sulfate-dependent cell entry mechanism. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Chamberlain, Kyle; Fowler, Veronica L; Barnett, Paul V; Gold, Sarah; Wadsworth, Jemma; Knowles, Nick J; Jackson, Terry
2015-09-01
Vaccination remains the most effective tool for control of foot-and-mouth disease both in endemic countries and as an emergency preparedness for new outbreaks. Foot-and-mouth disease vaccines are chemically inactivated virus preparations and the production of new vaccines is critically dependent upon cell culture adaptation of field viruses, which can prove problematic. A major driver of cell culture adaptation is receptor availability. Field isolates of foot-and-mouth disease virus (FMDV) use RGD-dependent integrins as receptors, whereas cell culture adaptation often selects for variants with altered receptor preferences. Previously, two independent sites on the capsid have been identified where mutations are associated with improved cell culture growth. One is a shallow depression formed by the three major structural proteins (VP1-VP3) where mutations create a heparan sulphate (HS)-binding site (the canonical HS-binding site). The other involves residues of VP1 and is located at the fivefold symmetry axis. For some viruses, changes at this site result in HS binding; for others, the receptors are unknown. Here, we report the identification of a novel site on VP2 where mutations resulted in an expanded cell tropism of a vaccine variant of A/IRN/87 (called A - ). Furthermore, we show that introducing the same mutations into a different type A field virus (A/TUR/2/2006) resulted in the same expanded cell culture tropism as the A/IRN/87 A - vaccine variant. These observations add to the evidence for multiple cell attachment mechanisms for FMDV and may be useful for vaccine manufacture when cell culture adaptation proves difficult.
Identification of a novel cell culture adaptation site on the capsid of foot-and-mouth disease virus
Chamberlain, Kyle; Fowler, Veronica L.; Barnett, Paul V.; Gold, Sarah; Wadsworth, Jemma; Knowles, Nick J.
2015-01-01
Vaccination remains the most effective tool for control of foot-and-mouth disease both in endemic countries and as an emergency preparedness for new outbreaks. Foot-and-mouth disease vaccines are chemically inactivated virus preparations and the production of new vaccines is critically dependent upon cell culture adaptation of field viruses, which can prove problematic. A major driver of cell culture adaptation is receptor availability. Field isolates of foot-and-mouth disease virus (FMDV) use RGD-dependent integrins as receptors, whereas cell culture adaptation often selects for variants with altered receptor preferences. Previously, two independent sites on the capsid have been identified where mutations are associated with improved cell culture growth. One is a shallow depression formed by the three major structural proteins (VP1–VP3) where mutations create a heparan sulphate (HS)-binding site (the canonical HS-binding site). The other involves residues of VP1 and is located at the fivefold symmetry axis. For some viruses, changes at this site result in HS binding; for others, the receptors are unknown. Here, we report the identification of a novel site on VP2 where mutations resulted in an expanded cell tropism of a vaccine variant of A/IRN/87 (called A − ). Furthermore, we show that introducing the same mutations into a different type A field virus (A/TUR/2/2006) resulted in the same expanded cell culture tropism as the A/IRN/87 A − vaccine variant. These observations add to the evidence for multiple cell attachment mechanisms for FMDV and may be useful for vaccine manufacture when cell culture adaptation proves difficult. PMID:26296881
Tan, Xiahui; Khalil, Najwa; Tesarik, Candice; Vanapalli, Karunasri; Yaputra, Viki; Alkhouri, Hatem; Oliver, Brian G G; Armour, Carol L; Hughes, J Margaret
2012-04-01
In asthma, airway smooth muscle (ASM) chemokine secretion can induce mast cell recruitment into the airways. The functions of the mast cell chemoattractant CXCL10, and other chemokines, are regulated by binding to heparan sulphates such as syndecan-4. This study is the first demonstration that airway smooth muscle cells (ASMC) from people with and without asthma express and shed syndecan-4 under basal conditions. Syndecan-4 shedding was enhanced by stimulation for 24 h with the Th1 cytokines interleukin-1β (IL-1β) or tumor necrosis factor-α (TNF-α), but not interferon-γ (IFNγ), nor the Th2 cytokines IL-4 and IL-13. ASMC stimulation with IL-1β, TNF-α, and IFNγ (cytomix) induced the highest level of syndecan-4 shedding. Nonasthmatic and asthmatic ASM cell-associated syndecan-4 protein expression was also increased by TNF-α or cytomix at 4-8 h, with the highest levels detected in cytomix-stimulated asthmatic cells. Cell-associated syndecan-4 levels were decreased by 24 h, whereas shedding remained elevated at 24 h, consistent with newly synthesized syndecan-4 being shed. Inhibition of ASMC matrix metalloproteinase-2 did not prevent syndecan-4 shedding, whereas inhibition of ERK MAPK activation reduced shedding from cytomix-stimulated ASMC. Although ERK inhibition had no effect on syndecan-4 mRNA levels stimulated by cytomix, it did cause an increase in cell-associated syndecan-4 levels, consistent with the shedding being inhibited. In conclusion, ASMC produce and shed syndecan-4 and although this is increased by the Th1 cytokines, the MAPK ERK only regulates shedding. ASMC syndecan-4 production during Th1 inflammatory conditions may regulate chemokine activity and mast cell recruitment to the ASM in asthma.
Wang, Bin; Lai, Xiaohan; Price, Christopher; Thompson, William R.; Li, Wen; Quabili, Tonima R.; Tseng, Wei-Ju; Liu, Xiaowei Sherry; Zhang, Hong; Pan, Jun; Kirn-Safran, Catherine B.; Farach-Carson, Mary C.; Wang, Liyun
2013-01-01
The pericellular matrix (PCM), a thin “coating” surrounding nearly all mammalian cells, plays a critical role in many cell-surface phenomena. In osteocytes, the PCM is believed to control both “outside-in” (mechanosensing) and “inside-out” (signaling molecule transport) processes. However, the osteocytic PCM is challenging to study in situ because it is thin (~100nm) and enclosed in mineralized matrix. To this end, we recently developed a novel tracer velocimetry approach that combined fluorescence recovery after photobleaching (FRAP) imaging with hydrodynamic modeling to quantify the osteocytic PCM in young murine bone (Wang et al., J Bone Miner Res. 2013; 28:1075–86). In this study, we applied the technique to older mice expressing or deficient for perlecan/HSPG2, a large heparan-sulfate proteoglycan normally secreted in osteocytic PCM. The objectives were to i) characterize transport within an altered PCM; ii) to test the sensitivity of our approach in detecting the PCM alterations; and iii) to dissect the roles of the PCM in osteocyte mechanosensing. We found that i) solute transport increases in the perlecan-deficient (hypomorphic: Hypo) mice compared with control mice; ii) PCM fiber density decreases with aging and perlecan deficiency; iii) the osteocytes in the Hypo bones are predicted to experience higher shear stress (+34%), but decreased fluid drag force (−35%) under 3N peak tibial loading, and iv) when subjected to tibial loading in a preliminary in vivo experiment, the Hypo mice did not respond to the anabolic stimuli as CTL mice. These findings support the hypothesis that the PCM fibers act as osteocyte’s sensing antennae, regulating load-induced cellular stimulations and thus bone’s sensitivity and in vivo bone adaptation. If this hypothesis is further confirmed, osteocytic PCM could be new targets to develop osteoporosis treatments by modulating bone’s intrinsic sensitivity to mechanical loading and be used to design patient-specific exercise regimens to promote bone formation. PMID:24115222
NASA Astrophysics Data System (ADS)
Wu, Jiandong; Wei, Juan; Hogan, John D.; Chopra, Pradeep; Joshi, Apoorva; Lu, Weigang; Klein, Joshua; Boons, Geert-Jan; Lin, Cheng; Zaia, Joseph
2018-03-01
Among dissociation methods, negative electron transfer dissociation (NETD) has been proven the most useful for glycosaminoglycan (GAG) sequencing because it produces informative fragmentation, a low degree of sulfate losses, high sensitivity, and translatability to multiple instrument types. The challenge, however, is to distinguish positional sulfation. In particular, NETD has been reported to fail to differentiate 4-O- versus 6-O-sulfation in chondroitin sulfate decasaccharide. This raised the concern of whether NETD is able to differentiate the rare 3-O-sulfation from predominant 6-O-sulfation in heparan sulfate (HS) oligosaccharides. Here, we report that NETD generates highly informative spectra that differentiate sites of O-sulfation on glucosamine residues, enabling structural characterizations of synthetic HS isomers containing 3-O-sulfation. Further, lyase-resistant 3-O-sulfated tetrasaccharides from natural sources were successfully sequenced. Notably, for all of the oligosaccharides in this study, the successful sequencing is based on NETD tandem mass spectra of commonly observed deprotonated precursor ions without derivatization or metal cation adduction, simplifying the experimental workflow and data interpretation. These results demonstrate the potential of NETD as a sensitive analytical tool for detailed, high-throughput structural analysis of highly sulfated GAGs. [Figure not available: see fulltext.
Pradines, Joël R.; Beccati, Daniela; Lech, Miroslaw; Ozug, Jennifer; Farutin, Victor; Huang, Yongqing; Gunay, Nur Sibel; Capila, Ishan
2016-01-01
Complex mixtures of molecular species, such as glycoproteins and glycosaminoglycans, have important biological and therapeutic functions. Characterization of these mixtures with analytical chemistry measurements is an important step when developing generic drugs such as biosimilars. Recent developments have focused on analytical methods and statistical approaches to test similarity between mixtures. The question of how much uncertainty on mixture composition is reduced by combining several measurements still remains mostly unexplored. Mathematical frameworks to combine measurements, estimate mixture properties, and quantify remaining uncertainty, i.e. a characterization extent, are introduced here. Constrained optimization and mathematical modeling are applied to a set of twenty-three experimental measurements on heparan sulfate, a mixture of linear chains of disaccharides having different levels of sulfation. While this mixture has potentially over two million molecular species, mathematical modeling and the small set of measurements establish the existence of nonhomogeneity of sulfate level along chains and the presence of abundant sulfate repeats. Constrained optimization yields not only estimations of sulfate repeats and sulfate level at each position in the chains but also bounds on these levels, thereby estimating the extent of characterization of the sulfation pattern which is achieved by the set of measurements. PMID:27112127
Pradines, Joël R; Beccati, Daniela; Lech, Miroslaw; Ozug, Jennifer; Farutin, Victor; Huang, Yongqing; Gunay, Nur Sibel; Capila, Ishan
2016-04-26
Complex mixtures of molecular species, such as glycoproteins and glycosaminoglycans, have important biological and therapeutic functions. Characterization of these mixtures with analytical chemistry measurements is an important step when developing generic drugs such as biosimilars. Recent developments have focused on analytical methods and statistical approaches to test similarity between mixtures. The question of how much uncertainty on mixture composition is reduced by combining several measurements still remains mostly unexplored. Mathematical frameworks to combine measurements, estimate mixture properties, and quantify remaining uncertainty, i.e. a characterization extent, are introduced here. Constrained optimization and mathematical modeling are applied to a set of twenty-three experimental measurements on heparan sulfate, a mixture of linear chains of disaccharides having different levels of sulfation. While this mixture has potentially over two million molecular species, mathematical modeling and the small set of measurements establish the existence of nonhomogeneity of sulfate level along chains and the presence of abundant sulfate repeats. Constrained optimization yields not only estimations of sulfate repeats and sulfate level at each position in the chains but also bounds on these levels, thereby estimating the extent of characterization of the sulfation pattern which is achieved by the set of measurements.
NASA Astrophysics Data System (ADS)
Pradines, Joël R.; Beccati, Daniela; Lech, Miroslaw; Ozug, Jennifer; Farutin, Victor; Huang, Yongqing; Gunay, Nur Sibel; Capila, Ishan
2016-04-01
Complex mixtures of molecular species, such as glycoproteins and glycosaminoglycans, have important biological and therapeutic functions. Characterization of these mixtures with analytical chemistry measurements is an important step when developing generic drugs such as biosimilars. Recent developments have focused on analytical methods and statistical approaches to test similarity between mixtures. The question of how much uncertainty on mixture composition is reduced by combining several measurements still remains mostly unexplored. Mathematical frameworks to combine measurements, estimate mixture properties, and quantify remaining uncertainty, i.e. a characterization extent, are introduced here. Constrained optimization and mathematical modeling are applied to a set of twenty-three experimental measurements on heparan sulfate, a mixture of linear chains of disaccharides having different levels of sulfation. While this mixture has potentially over two million molecular species, mathematical modeling and the small set of measurements establish the existence of nonhomogeneity of sulfate level along chains and the presence of abundant sulfate repeats. Constrained optimization yields not only estimations of sulfate repeats and sulfate level at each position in the chains but also bounds on these levels, thereby estimating the extent of characterization of the sulfation pattern which is achieved by the set of measurements.
Yano, Junko; Noverr, Mairi C; Fidel, Paul L
2017-03-14
Despite acute inflammation by polymorphonuclear neutrophils (PMNs) during vulvovaginal candidiasis (VVC), clearance of Candida fails to occur. The purpose of this study was to uncover the mechanism of vaginal PMN dysfunction. Designs included assessing PMN migration, proinflammatory mediators, and tissue damage (by analysis of the activity of lactate dehydrogenase [LDH]) in mice susceptible (C3H/HeN-C57BL/6) or resistant (CD-1) to chronic VVC (CVVC-S or CVVC-R) and testing morphology-specific Candida albicans strains under conditions of preinduced PMN migration (CVVC-S mice) or PMN depletion (CVVC-R mice). In vitro designs included evaluation of C. albicans killing by elicited vaginal or peritoneal PMNs in standard or vaginal conditioned medium (VCM). Results showed that despite significant migration of PMNs and high levels of vaginal beta interleukin-1 (IL-1β) and alarmin S100A8, CVVC-S mice failed to reduce vaginal fungal burden irrespective of morphology or whether PMNs were present pre- or postinoculation, and had high LDH levels. In contrast, CVVC-R mice had reduced fungal burden and low LDH levels following PMN recruitment and IL-1β/S100A8 production, but maintained colonization in the absence of PMNs. Elicited vaginal and peritoneal PMNs showed substantial killing activity in standard media or VCM from CVVC-R mice but not in VCM from CVVC-S mice. The inhibitory effect of VCM from CVVC-S mice was unaffected by endogenous or exogenous estrogen and was ablated following depletion/neutralization of Mac-1 ligands using Mac-1 +/+ PMNs or recombinant Mac-1. Heparan sulfate (HS) was identified as the putative inhibitor as evidenced by the rescue of PMN killing following heparanase treatment of VCM, as well as by inhibition of killing by purified HS. These results suggest that vaginal HS is linked to PMN dysfunction in CVVC-S mice as a competitive ligand for Mac-1. IMPORTANCE Vaginal candidiasis, caused by Candida albicans , affects a significant number of women worldwide. Despite an acute inflammatory response by neutrophils during infection, the response fails to reduce the organism. Instead, the response is considered a key process underlying the symptoms of vaginitis. Therefore, it is important to determine the mechanism(s) associated with the lack of vaginal neutrophil antifungal activity. The established mouse model of Candida vaginitis was used to uncover the mechanism of neutrophil dysfunction. Results revealed that heparan sulfate present in the vagina of mice susceptible to chronic vaginitis served as a competitive ligand for the receptor (Mac-1) necessary for fungal recognition and neutrophil-mediated killing. This inhibitory function of heparan sulfate, confirmed through several approaches, provides the first evidence to explain the lack of antifungal immune reactivity during vaginal candidiasis. This finding paves the way for design of therapeutic strategies to reduce/eliminate symptomatic vaginal candidiasis and restore quality of life to those affected. Copyright © 2017 Yano et al.
Wang, Tianyi; Lai, Janice H; Yang, Fan
2016-12-01
Cell-based therapies offer great promise for repairing cartilage. Previous strategies often involved using a single cell population such as stem cells or chondrocytes. A mixed cell population may offer an alternative strategy for cartilage regeneration while overcoming donor scarcity. We have recently reported that adipose-derived stem cells (ADSCs) can catalyze neocartilage formation by neonatal chondrocytes (NChons) when mixed co-cultured in 3D hydrogels in vitro. However, it remains unknown how the biochemical and mechanical cues of hydrogels modulate cartilage formation by mixed cell populations in vivo. The present study seeks to answer this question by co-encapsulating ADSCs and NChons in 3D hydrogels with tunable stiffness (∼1-33 kPa) and biochemical cues, and evaluating cartilage formation in vivo using a mouse subcutaneous model. Three extracellular matrix molecules were examined, including chondroitin sulfate (CS), hyaluronic acid (HA), and heparan sulfate (HS). Our results showed that the type of biochemical cue played a dominant role in modulating neocartilage deposition. CS and HA enhanced type II collagen deposition, a desirable phenotype for articular cartilage. In contrast, HS promoted fibrocartilage phenotype with the upregulation of type I collagen and failed to retain newly deposited matrix. Hydrogels with stiffnesses of ∼7-33 kPa led to a comparable degree of neocartilage formation, and a minimal initial stiffness was required to retain hydrogel integrity over time. Results from this study highlight the important role of matrix cues in directing neocartilage formation, and they offer valuable insights in guiding optimal scaffold design for cartilage regeneration by using mixed cell populations.
Hasegawa, Mayumi; Cheng, Jun; Maruyama, Satoshi; Yamazaki, Manabu; Abé, Tatsuya; Babkair, Hamzah; Saito, Chikara; Saku, Takashi
2016-05-01
The intercellular deposit of perlecan, a basement-membrane type heparan sulfate proteoglycan, is considered to function as a growth factor reservoir and is enhanced in oral epithelial dysplasia and carcinoma in situ (CIS). However, it remains unknown which types of growth factors function in these perlecan-enriched epithelial conditions. The aim of this study was to determine immunohistochemically which growth factors were associated with perlecan in normal oral epithelia and in different epithelial lesions from dysplasia and CIS to squamous cell carcinoma (SCC). Eighty-one surgical tissue specimens of oral SCC containing different precancerous stages, along with ten of normal mucosa, were examined by immunohistochemistry for growth factors. In normal epithelia, perlecan and growth factors were not definitely expressed. In epithelial dysplasia, VEGF, SHH, KGF, Flt-1, and Flk-1were localized in the lower half of rete ridges (in concordance with perlecan, 33-100%), in which Ki-67 positive cells were densely packed. In CIS, perlecan and those growth factors/receptors were more strongly expressed in the cell proliferating zone (63-100%). In SCC, perlecan and KGF disappeared from carcinoma cells but emerged in the stromal space (65-100%), while VEGF, SHH, and VEGF receptors remained positive in SCC cells (0%). Immunofluorescence showed that the four growth factors were shown to be produced by three oral SCC cell lines and that their signals were partially overlapped with perlecan signals. The results indicate that perlecan and its binding growth factors are differentially expressed and function in specific manners before (dysplasia/CIS) and after (SCC) invasion of dysplasia/carcinoma cells. Copyright © 2016 Elsevier GmbH. All rights reserved.
Bhakta, Gajadhar; Ekaputra, Andrew K; Rai, Bina; Abbah, Sunny A; Tan, Tuan Chun; Le, Bach Quang; Chatterjea, Anindita; Hu, Tao; Lin, Tingxuan; Arafat, M Tarik; van Wijnen, Andre J; Goh, James; Nurcombe, Victor; Bhakoo, Kishore; Birch, William; Xu, Li; Gibson, Ian; Wong, Hee-Kit; Cool, Simon M
2018-05-01
Interbody spinal fusion relies on the use of external fixation and the placement of a fusion cage filled with graft materials (scaffolds) without regard for their mechanical performance. Stability at the fusion site is instead reliant on fixation hardware combined with a selected cage. Ideally, scaffolds placed into the cage should both support the formation of new bone and contribute to the mechanical stability at the fusion site. We recently developed a scaffold consisting of silane-modified PCL-TCP (PCL-siTCP) with mechanical properties that can withstand the higher loads generated in the spine. To ensure the scaffold more closely mimicked the bone matrix, we incorporated collagen (Col) and a heparan sulfate glycosaminoglycan sugar (HS3) with increased affinity for heparin-binding proteins such as bone morphogenetic protein-2 (BMP-2). The osteostimulatory characteristic of this novel device delivering exogenous BMP2 was assessed in vitro and in vivo as a prelude to future spinal fusion studies with this device. A combination of cell-free assays (BMP2 release), progenitor cell-based assays (BMP2 bioactivity, cell proliferation and differentiation), and rodent ectopic bone formation assays was used to assess the osteostimulatory characteristics of the PCL-siTCP-based scaffolds. Freshly prepared rat mesenchymal stem cells were used to determine reparative cell proliferation and differentiation on the PCL-siTCP-based scaffolds over a 28-day period in vitro. The bioactivity of BMP2 released from the scaffolds was assessed on progenitor cells over a 28-day period using ALP activity assays and release kinetics as determined by enzyme-linked immunosorbent assay. For ectopic bone formation, intramuscular placement of scaffolds into Sprague Dawley rats (female, 4 weeks old, 120-150 g) was achieved in five animals, each receiving four treatments randomized for location along the limb. The four groups tested were (1) PCL-siTCP/Col (5-mm diameter×1-mm thickness), PCL-siTCP/Col/BMP2 (5 µg), (3) PCL-siTCP/Col/HS3 (25 µg), and (4) PCL-siTCP/Col/HS3/BMP2 (25 and 5 µg, respectively). Bone formation was evaluated at 8 weeks post implantation by microcomputed tomography (µCT) and histology. Progenitor cell-based assays (proliferation, mRNA transcripts, and ALP activity) confirmed that BMP2 released from PCL-siTCP/Col/HS3 scaffolds increased ALP expression and mRNA levels of the osteogenic biomarkers Runx2, Col1a2, ALP, and bone gla protein-osteocalcin compared with devices without HS3. When the PCL-siTCP/Col/HS3/BMP2 scaffolds were implanted into rat hamstring muscle, increased bone formation (as determined by two-dimensional and three-dimensional µCTs and histologic analyses) was observed compared with scaffolds lacking BMP2. More consistent increases in the amount of ectopic bone were observed for the PCL-siTCP/Col/HS3/BMP2 implants compared with PCL-siTCP/Col/BMP2. Also, increased mineralizing tissue within the pores of the scaffold was seen with modified-tetrachrome histology, a result confirmed by µCT, and a modest but detectable increase in both the number and the thickness of ectopic bone structures were observed with the PCL-siTCP/Col/HS3/BMP2 implants. The combination of PCL-siTCP/Col/HS3/BMP2 thus represents a promising avenue for further development as a bone graft alternative for spinal fusion surgery. Copyright © 2017 Elsevier Inc. All rights reserved.
Heparin and related polysaccharides: Synthesis using recombinant enzymes and metabolic engineering
Suflita, Matthew; Fu, Li; He, Wenqin; Koffas, Mattheos; Linhardt, Robert J.
2015-01-01
Glycosaminoglycans are linear anionic polysaccharides that exhibit a number of important biological and pharmacological activities. The two most prominent members of this class of polysaccharides are heparin/heparan sulfate and the chondroitin sulfates (including dermatan sulfate). These polysaccharides, having complex structures and polydispersity, are biosynthesized in the Golgi of most animal cells. The chemical synthesis of these glycosaminoglycans is precluded by their structural complexity. Today, we depend on food animal tissues for their isolation and commercial production. Ton quantities of these glycosaminoglycans are used annually as pharmaceuticals and nutraceuticals. The variability of animal-sourced glycosaminoglycans, their inherent impurities, the limited availability of source tissues, the poor control of these source materials, and their manufacturing processes, suggest a need for new approaches for their production. Over the past decade there have been major efforts in the biotechnological production of these glycosaminoglycans. This mini-review focuses on the use of recombinant enzymes and metabolic engineering for the production of heparin and chondroitin sulfates. PMID:26219501
Craniofacial skeletal defects of adult zebrafish glypican 4 (knypek) mutants
LeClair, Elizabeth E.; Mui, Stephanie R.; Huang, Angela; Topczewska, Jolanta M.; Topczewski, Jacek
2010-01-01
The heparan sulfate proteoglycan Glypican 4 (Gpc4) is part of the Wnt/planar cell polarity pathway, which is required for convergence and extension during zebrafish gastrulation. To observe Glypican 4-deficient phenotypes at later stages, we rescued gpc4−/− (knypek) homozygotes and raised them for more than one year. Adult mutants showed diverse cranial malformations of both dermal and endochondral bones, ranging from shortening of the rostral-most skull to loss of the symplectic. Additionally, the adult palatoquadrate cartilage was disorganized, with abnormal chondrocyte orientation. To understand how the palatoquadrate cartilage normally develops, we examined a juvenile series of wild type and mutant specimens. This identified two novel domains of elongated chondrocytes in the larval palatoquadrate, which normally form prior to endochondral ossification. In contrast, gpc4−/− larvae never form these domains, suggesting a failure of chondrocyte orientation, though not differentiation. Our findings implicate Gpc4 in the regulation of zebrafish cartilage and bone morphogenesis. PMID:19777561
Staples, Gregory O; Naimy, Hicham; Yin, Hongfeng; Kileen, Kevin; Kraiczek, Karsten; Costello, Catherine E; Zaia, Joseph
2010-01-15
Heparan sulfate (HS) and heparin are linear, heterogeneous carbohydrates of the glycosaminoglycan (GAG) family that are modified by N-acetylation, N-sulfation, O-sulfation, and uronic acid epimerization. HS interacts with growth factors in the extracellular matrix, thereby modulating signaling pathways that govern cell growth, development, differentiation, proliferation, and adhesion. High-performance liquid chromatography (HPLC)-chip-based hydrophilic interaction liquid chromatography/mass spectrometry has emerged as a method for analyzing the domain structure of GAGs. However, analysis of highly sulfated GAG structures decasaccharide or larger in size has been limited by spray instability in the negative-ion mode. This report demonstrates that addition of postcolumn makeup flow to the amide-HPLC-chip configuration permits robust and reproducible analysis of extended GAG domains (up to degree of polymerization 18) from HS and heparin. This platform provides quantitative information regarding the oligosaccharide profile, degree of sulfation, and nonreducing chain termini. It is expected that this technology will enable quantitative, comparative glycomics profiling of extended GAG oligosaccharide domains of functional interest.
R-spondins can potentiate WNT signaling without LGRs.
Lebensohn, Andres M; Rohatgi, Rajat
2018-02-06
The WNT signaling pathway regulates patterning and morphogenesis during development and promotes tissue renewal and regeneration in adults. The R-spondin (RSPO) family of four secreted proteins, RSPO1-4, amplifies target cell sensitivity to WNT ligands by increasing WNT receptor levels. Leucine-rich repeat-containing G-protein coupled receptors (LGRs) 4-6 are considered obligate high-affinity receptors for RSPOs. We discovered that RSPO2 and RSPO3, but not RSPO1 or RSPO4, can potentiate WNT/β-catenin signaling in the absence of all three LGRs. By mapping the domains on RSPO3 that are necessary and sufficient for this activity, we show that the requirement for LGRs is dictated by the interaction between RSPOs and the ZNRF3/RNF43 E3 ubiquitin ligases and that LGR-independent signaling depends on heparan sulfate proteoglycans (HSPGs). We propose that RSPOs can potentiate WNT signals through distinct mechanisms that differ in their use of either LGRs or HSPGs, with implications for understanding their biological functions. © 2017, Lebensohn et al.
R-spondins can potentiate WNT signaling without LGRs
2018-01-01
The WNT signaling pathway regulates patterning and morphogenesis during development and promotes tissue renewal and regeneration in adults. The R-spondin (RSPO) family of four secreted proteins, RSPO1-4, amplifies target cell sensitivity to WNT ligands by increasing WNT receptor levels. Leucine-rich repeat-containing G-protein coupled receptors (LGRs) 4-6 are considered obligate high-affinity receptors for RSPOs. We discovered that RSPO2 and RSPO3, but not RSPO1 or RSPO4, can potentiate WNT/β-catenin signaling in the absence of all three LGRs. By mapping the domains on RSPO3 that are necessary and sufficient for this activity, we show that the requirement for LGRs is dictated by the interaction between RSPOs and the ZNRF3/RNF43 E3 ubiquitin ligases and that LGR-independent signaling depends on heparan sulfate proteoglycans (HSPGs). We propose that RSPOs can potentiate WNT signals through distinct mechanisms that differ in their use of either LGRs or HSPGs, with implications for understanding their biological functions. PMID:29405118
An Attractive Reelin Gradient Establishes Synaptic Lamination in the Vertebrate Visual System.
Di Donato, Vincenzo; De Santis, Flavia; Albadri, Shahad; Auer, Thomas Oliver; Duroure, Karine; Charpentier, Marine; Concordet, Jean-Paul; Gebhardt, Christoph; Del Bene, Filippo
2018-03-07
A conserved organizational and functional principle of neural networks is the segregation of axon-dendritic synaptic connections into laminae. Here we report that targeting of synaptic laminae by retinal ganglion cell (RGC) arbors in the vertebrate visual system is regulated by a signaling system relying on target-derived Reelin and VLDLR/Dab1a on the projecting neurons. Furthermore, we find that Reelin is distributed as a gradient on the target tissue and stabilized by heparan sulfate proteoglycans (HSPGs) in the extracellular matrix (ECM). Through genetic manipulations, we show that this Reelin gradient is important for laminar targeting and that it is attractive for RGC axons. Finally, we suggest a comprehensive model of synaptic lamina formation in which attractive Reelin counter-balances repulsive Slit1, thereby guiding RGC axons toward single synaptic laminae. We establish a mechanism that may represent a general principle for neural network assembly in vertebrate species and across different brain areas. Copyright © 2018 Elsevier Inc. All rights reserved.
Chen, Yao; Mohammadi, Moosa; Flanagan, John G.
2009-01-01
Summary Graded guidance labels are widely used in neural map formation, but it is not well understood which potential strategy leads to their graded expression. In midbrain tectal map development, FGFs can induce an entire midbrain, but their protein distribution is unclear, nor is it known whether they may act instructively to produce graded gene expression. Using a receptor-alkaline phosphatase fusion probe, we find a long-range posterior>anterior FGF protein gradient spanning the midbrain. Heparan sulfate proteoglycan (HSPG) is required for this gradient. To test whether graded FGF concentrations can instruct graded gene expression, a quantitative tectal explant assay was developed. Engrailed-2 and ephrin-As, normally in posterior>anterior tectal gradients, showed graded upregulation. Moreover, EphAs, normally in anterior>posterior countergradients, showed coordinately graded downregulation. These results provide a mechanism to establish graded mapping labels, and more generally provide a developmental strategy to coordinately induce a structure and pattern its cell properties in gradients. PMID:19555646
Decoy receptor 3 suppresses TLR2-mediated B cell activation by targeting NF-κB.
Huang, Zi-Ming; Kang, Jhi-Kai; Chen, Chih-Yu; Tseng, Tz-Hau; Chang, Chien-Wen; Chang, Yung-Chi; Tai, Shyh-Kuan; Hsieh, Shie-Liang; Leu, Chuen-Miin
2012-06-15
Decoy receptor 3 (DcR3) is a soluble protein in the TNFR superfamily. Its known ligands include Fas ligand, homologous to lymphotoxin, showing inducible expression, and competing with HSV glycoprotein D for herpes virus entry mediator, a receptor expressed by T lymphocytes, TNF-like molecule 1A, and heparan sulfate proteoglycans. DcR3 has been reported to modulate the functions of T cells, dendritic cells, and macrophages; however, its role in regulating B cell activation is largely unknown. In this study, we found that the DcR3.Fc fusion protein bound to human and mouse B cells and suppressed the activation of B cells. DcR3.Fc attenuated Staphylococcus aureus, IgM-, Pam(3)CSK(4)-, and LPS-mediated B cell proliferation but did not affect cytokine-induced B cell growth. In the presence of these mitogens, DcR3.Fc did not induce B cell apoptosis, suggesting that DcR3 may inhibit the signal(s) important for B cell activation. Because the combination of Fas.Fc, LT-βR.Fc (homologous to lymphotoxin, showing inducible expression, and competing with HSV glycoprotein D for herpes virus entry mediator, a receptor expressed by T lymphocytes receptor), and DR3.Fc (TNF-like molecule 1A receptor) did not suppress B cell proliferation and because the biological effect of DcR3.Fc on B cells was not blocked by heparin, we hypothesize that a novel ligand(s) of DcR3 mediates its inhibitory activity on B cells. Moreover, we found that TLR2-stimulated NF-κB p65 activation and NF-κB-driven luciferase activity were attenuated by DcR3.Fc. The TLR2-induced cytokine production by B cells was consistently reduced by DcR3. These results imply that DcR3 may regulate B cell activation by suppressing the activation of NF-κB.
Poupard, Nicolas; Badarou, Pamela; Fasani, Fabienne; Groult, Hugo; Bridiau, Nicolas; Sannier, Frédéric; Bordenave-Juchereau, Stéphanie; Kieda, Claudine; Piot, Jean-Marie; Grillon, Catherine; Fruitier-Arnaudin, Ingrid; Maugard, Thierry
2017-05-09
Heparanase is overexpressed by tumor cells and degrades the extracellular matrix proteoglycans through cleavage of heparan sulfates (HS), allowing pro-angiogenic factor release and thus playing a key role in tumor angiogenesis and metastasis. Here we propose new HS analogs as potent heparanase inhibitors: Heparin as a positive control, Dextran Sulfate, λ-Carrageenan, and modified forms of them obtained by depolymerization associated to glycol splitting (RD-GS). After heparanase activity assessment, 11 kDa RD-GS-λ-Carrageenan emerged as the most effective heparanase inhibitor with an IC 50 of 7.32 ng/mL compared to 10.7 ng/mL for the 16 kDa unfractionated heparin. The fractionated polysaccharides were then tested in a heparanase-rich medium-based in vitro model, mimicking tumor microenvironment, to determine their effect on microvascular endothelial cells (HSkMEC) angiogenesis. As a preliminary study, we identified that under hypoxic and nutrient poor conditions, MCF-7 cancer cells released much more mature heparanase in their supernatant than in normal conditions. Then a Matrigel TM assay using HSkMEC cultured under hypoxic conditions in the presence (or not) of this heparanase-rich supernatant was realized. Adding heparanase-rich media strongly enhanced angiogenic network formation with a production of twice more pseudo-vessels than with the control. When sulfated polysaccharides were tested in this angiogenesis assay, RD-GS-λ-Carrageenan was identified as a promising anti-angiogenic agent.
Mellor, P; Harvey, J R; Murphy, K J; Pye, D; O'Boyle, G; Lennard, T W J; Kirby, J A; Ali, S
2007-01-01
Expression of the chemokine receptor CXCR4 allows breast cancer cells to migrate towards specific metastatic target sites which constitutively express CXCL12. In this study, we determined whether this interaction could be disrupted using short-chain length heparin oligosaccharides. Radioligand competition binding assays were performed using a range of heparin oligosaccharides to compete with polymeric heparin or heparan sulphate binding to I125 CXCL12. Heparin dodecasaccharides were found to be the minimal chain length required to efficiently bind CXCL12 (71% inhibition; P<0.001). These oligosaccharides also significantly inhibited CXCL12-induced migration of CXCR4-expressing LMD MDA-MB 231 breast cancer cells. In addition, heparin dodecasaccharides were found to have less anticoagulant activity than either a smaller quantity of polymeric heparin or a similar amount of the low molecular weight heparin pharmaceutical product, Tinzaparin. When given subcutaneously in a SCID mouse model of human breast cancer, heparin dodecasaccharides had no effect on the number of lung metastases, but did however inhibit (P<0.05) tumour growth (lesion area) compared to control groups. In contrast, polymeric heparin significantly inhibited both the number (P<0.001) and area of metastases, suggesting a differing mechanism for the action of polymeric and heparin-derived oligosaccharides in the inhibition of tumour growth and metastases. PMID:17726466
White, April F; Mazur, Marina; Sorscher, Eric J; Zinn, Kurt R; Ponnazhagan, Selvarangan
2008-12-01
Cystic fibrosis (CF) is a common genetic disease characterized by defects in the expression of the CF transmembrane conductance regulator (CFTR) gene. Gene therapy offers better hope for the treatment of CF. Adeno-associated viral (AAV) vectors are capable of stable expression with low immunogenicity. Despite their potential in CF gene therapy, gene transfer efficiency by AAV is limited because of pathophysiological barriers in these patients. Although a few AAV serotypes have shown better transduction compared with the AAV2-based vectors, gene transfer efficiency in human airway epithelium has still not reached therapeutic levels. To engineer better AAV vectors for enhanced gene delivery in human airway epithelium, we developed and characterized mutant AAV vectors by genetic capsid modification, modeling the well-characterized AAV2 serotype. We genetically incorporated putative high-affinity peptide ligands to human airway epithelium on the GH loop region of AAV2 capsid protein. Six independent mutant AAV were constructed, containing peptide ligands previously reported to bind with high affinity for known and unknown receptors on human airway epithelial cells. The vectors were tested on nonairway cells and nonpolarized and polarized human airway epithelial cells for enhanced infectivity. One of the mutant vectors, with the peptide sequence THALWHT, not only showed the highest transduction in undifferentiated human airway epithelial cells but also indicated significant transduction in polarized cells. Interestingly, this modified vector was also able to infect cells independently of the heparan sulfate proteoglycan receptor. Incorporation of this ligand on other AAV serotypes, which have shown improved gene transfer efficiency in the human airway epithelium, may enhance the application of AAV vectors in CF gene therapy.
Riedl, Sabrina; Leber, Regina; Rinner, Beate; Schaider, Helmut; Lohner, Karl; Zweytick, Dagmar
2015-11-01
Host defense-derived peptides have emerged as a novel strategy for the development of alternative anticancer therapies. In this study we report on characteristic features of human lactoferricin (hLFcin) derivatives which facilitate specific killing of cancer cells of melanoma, glioblastoma and rhabdomyosarcoma compared with non-specific derivatives and the synthetic peptide RW-AH. Changes in amino acid sequence of hLFcin providing 9-11 amino acids stretched derivatives LF11-316, -318 and -322 only yielded low antitumor activity. However, the addition of the repeat (di-peptide) and the retro-repeat (di-retro-peptide) sequences highly improved cancer cell toxicity up to 100% at 20 μM peptide concentration. Compared to the complete parent sequence hLFcin the derivatives showed toxicity on the melanoma cell line A375 increased by 10-fold and on the glioblastoma cell line U-87mg by 2-3-fold. Reduced killing velocity, apoptotic blebbing, activation of caspase 3/7 and formation of apoptotic DNA fragments proved that the active and cancer selective peptides, e.g. R-DIM-P-LF11-322, trigger apoptosis, whereas highly active, though non-selective peptides, such as DIM-LF11-318 and RW-AH seem to kill rapidly via necrosis inducing membrane lyses. Structural studies revealed specific toxicity on cancer cells by peptide derivatives with loop structures, whereas non-specific peptides comprised α-helical structures without loop. Model studies with the cancer membrane mimic phosphatidylserine (PS) gave strong evidence that PS only exposed by cancer cells is an important target for specific hLFcin derivatives. Other negatively charged membrane exposed molecules as sialic acid, heparan and chondroitin sulfate were shown to have minor impact on peptide activity. Copyright © 2015. Published by Elsevier B.V.
Ohtake, T; Fujimoto, Y; Ikuta, K; Saito, H; Ohhira, M; Ono, M; Kohgo, Y
1999-01-01
PR-39 is an endogenous proline-rich antimicrobial peptide which induces the synthesis of syndecan-1, a transmembrane heparan sulphate proteoglycan involved in cell-to-matrix interactions and wound healing. Previously, we revealed that the expression of syndecan-1 was reduced in human hepatocellular carcinomas with high metastatic potential and speculated that syndecan-1 played an important role in inhibition of invasion and metastasis. It is assumed that a modification of this process with PR-39 and syndecan-1 may result in a new strategy by which it can inhibit the invasion and metastasis. Therefore, we transduced a gene of PR-39 into human hepatocellular carcinoma cell line HLF, which shows a low expression of syndecan-1 and a high in vitro invasive activity, and examined whether this procedure could reduce the invasive activity of tumour cells. In two transfectants with PR-39 gene, the syndecan-1 expression was induced and the invasive activity in type I collagen-coated chamber was inhibited. Moreover, these transfectants showed the suppression of motile activity assayed by phagokinetic tracks in addition to the disorganization of actin filaments observed by a confocal imaging system. In contrast, five transfectants with syndecan-1 gene in the HLF cells revealed suppression of invasive activity but did not alter the motile activity and actin structures of the cell. These results suggest that PR-39 has functions involved in the suppression of motile activity and alteration of actin structure on human hepatocellular carcinoma cells in addition to the suppression of invasive activity which might result from the induction of syndecan-1 expression. © 1999 Cancer Research Campaign PMID:10507762
Generation of a Close-to-Native In Vitro System to Study Lung Cells-Extracellular Matrix Crosstalk.
Garlíková, Zuzana; Silva, Ana Catarina; Rabata, Anas; Potěšil, David; Ihnatová, Ivana; Dumková, Jana; Koledová, Zuzana; Zdráhal, Zbyněk; Vinarský, Vladimír; Hampl, Aleš; Pinto-do-Ó, Perpétua; Nascimento, Diana Santos
2018-01-01
Extracellular matrix (ECM) is an essential component of the tissue microenvironment, actively shaping cellular behavior. In vitro culture systems are often poor in ECM constituents, thus not allowing for naturally occurring cell-ECM interactions. This study reports on a straightforward and efficient method for the generation of ECM scaffolds from lung tissue and its subsequent in vitro application using primary lung cells. Mouse lung tissue was subjected to decellularization with 0.2% sodium dodecyl sulfate, hypotonic solutions, and DNase. Resultant ECM scaffolds were devoid of cells and DNA, whereas lung ECM architecture of alveolar region and blood and airway networks were preserved. Scaffolds were predominantly composed of core ECM and ECM-associated proteins such as collagens I-IV, nephronectin, heparan sulfate proteoglycan core protein, and lysyl oxidase homolog 1, among others. When homogenized and applied as coating substrate, ECM supported the attachment of lung fibroblasts (LFs) in a dose-dependent manner. After ECM characterization and biocompatibility tests, a novel in vitro platform for three-dimensional (3D) matrix repopulation that permits live imaging of cell-ECM interactions was established. Using this system, LFs colonized the ECM scaffolds, displaying a close-to-native morphology in intimate interaction with the ECM fibers, and showed nuclear translocation of the mechanosensor yes-associated protein (YAP), when compared with cells cultured in two dimensions. In conclusion, we developed a 3D-like culture system, by combining an efficient decellularization method with a live-imaging culture platform, to replicate in vitro native lung cell-ECM crosstalk. This is a valuable system that can be easily applied to other organs for ECM-related drug screening, disease modeling, and basic mechanistic studies.
Wang, Raymond Y; Aminian, Afshin; McEntee, Michael F; Kan, Shih-Hsin; Simonaro, Calogera M; Lamanna, William; Lawrence, Roger; Ellinwood, N. Matthew; Guerra, Catalina; Le, Steven Q; Dickson, Patricia I; Esko, Jeffrey D
2014-01-01
Background Treatment with intravenous enzyme replacement therapy and hematopoietic stem cell transplantation for mucopolysaccharidosis (MPS) type I does not address joint disease, resulting in persistent orthopedic complications and impaired quality of life. A proof-of-concept study was conducted to determine the safety, tolerability, and efficacy of intra-articular recombinant human iduronidase (IA-rhIDUA) enzyme replacement therapy in the canine MPS I model. Methods Four MPS I dogs underwent monthly rhIDUA injections (0.58 mg/joint) into the right elbow and knee for six months. Contralateral elbows and knees concurrently received normal saline. No intravenous rhIDUA therapy was administered. Monthly blood counts, chemistries, anti-rhIDUA antibody titers, and synovial fluid cell counts were measured. Lysosomal storage of synoviocytes and chondrocytes, synovial macrophages and plasma cells were scored at baseline and one month following the final injection. Results All injections were well-tolerated without adverse reactions. One animal required prednisone for spinal cord compression. There were no clinically significant abnormalities in blood counts or chemistries. Circulating anti-rhIDUA antibody titers gradually increased in all dogs except the prednisone-treated dog; plasma cells, which were absent in all baseline synovial specimens, were predominantly found in synovium of rhIDUA-treated joints at study-end. Lysosomal storage in synoviocytes and chondrocytes following 6 months of IA-rhIDUA demonstrated significant reduction compared to tissues at baseline, and saline-treated tissues at study-end. Mean joint synovial GAG levels in IA-rhIDUA joints was 8.62±5.86 μg/mg dry weight and 21.6±10.4 μg/mg dry weight in control joints (60% reduction). Cartilage heparan sulfate was also reduced in the IA-rhIDUA joints (113±39.5 ng/g wet weight) compared to saline-treated joints (142±56.4 ng/g wet weight). Synovial macrophage infiltration, which was present in all joints at baseline, was abolished in rhIDUA-treated joints only. Conclusions Intra-articular rhIDUA is well-tolerated and safe in the canine MPS I animal model. Qualitative and quantitative assessments indicate that IA-rhIDUA successfully reduces tissue and cellular GAG storage in synovium and articular cartilage, including cartilage deep to the articular surface, and eliminates inflammatory macrophages from synovial tissue. PMID:24951454
Shimada, Tsutomu; Kelly, Joan; LaMarr, William A; van Vlies, Naomi; Yasuda, Eriko; Mason, Robert W.; Mackenzie, William; Kubaski, Francyne; Giugliani, Roberto; Chinen, Yasutsugu; Yamaguchi, Seiji; Suzuki, Yasuyuki; Orii, Kenji E.; Fukao, Toshiyuki; Orii, Tadao; Tomatsu, Shunji
2014-01-01
Mucopolysaccharidoses (MPS) are caused by deficiency of one of a group of specific lysosomal enzymes, resulting in excessive accumulation of glycosaminoglycans (GAGs). We previously developed GAG assay methods using liquid chromatography tandem mass spectrometry (LC-MS/MS); however, it takes 4–5 min per sample for analysis. For the large numbers of samples in a screening program, a more rapid process is desirable. The automated high-throughput mass spectrometry (HT-MS/MS) system (RapidFire) integrates a solid phase extraction robot to concentrate and desalt samples prior to direction into the MS/MS without chromatographic separation; thereby allowing each sample to be processed within ten seconds (enabling screening of more than one million samples per year). The aim of this study was to develop a higher throughput system to assay heparan sulfate (HS) using HT-MS/MS, and to compare its reproducibility, sensitivity and specificity with conventional LC-MS/MS. HS levels were measured in blood (plasma and serum) from control subjects and patients with MPS II, III, or IV and in dried blood spots (DBS) from newborn controls and patients with MPS I, II, or III. Results obtained from HT-MS/MS showed 1) that there was a strong correlation of levels of disaccharides derived from HS in blood, between those calculated using conventional LC-MS/MS and HT-MS/MS, 2) that levels of HS in blood were significantly elevated in patients with MPS II and III, but not in MPS IVA, 3) that the level of HS in patients with a severe form of MPS II was higher than that in an attenuated form, 4) that reduction of blood HS level was observed in MPS II patients treated with enzyme replacement therapy or hematopoietic stem cell transplantation, and 5) that levels of HS in newborn DBS were elevated in patients with MPS I, II or III, compared to control newborns. In conclusion, HT-MS/MS provides much higher throughput than LC-MS/MS-based methods with similar sensitivity and specificity in an HS assay, indicating that HT-MS/MS may be feasible for diagnosis, monitoring, and newborn screening of MPS. PMID:25092413
Huang, Yu; Shi, Xiaofeng; Yu, Xiang; Leymarie, Nancy; Staples, Gregory O; Yin, Hongfeng; Killeen, Kevin; Zaia, Joseph
2011-11-01
Microfluidic chip-based hydrophilic interaction chromatography (HILIC) is a useful separation system for liquid chromatography-mass spectrometry (LC-MS) in compositional profiling of heparan sulfate (HS) oligosaccharides; however, ions observed using HILIC LC-MS are low in charge. Tandem MS of HS oligosaccharide ions with low charge results in undesirable losses of SO(3) from precursor ions during collision induced dissociation. One solution is to add metal cations to stabilize sulfate groups. Another is to add a nonvolatile, polar compound such as sulfolane, a molecule known to supercharge proteins, to produce a similar effect for oligosaccharides. We demonstrate use of a novel pulsed makeup flow (MUF) HPLC-chip. The chip enables controlled application of additives during specified chromatographic time windows and thus minimizes the extent to which nonvolatile additives build up in the ion source. The pulsed MUF system was applied to LC-MS/MS of HS oligosaccharides. Metal cations and sulfolane were tested as additives. The most promising results were obtained for sulfolane, for which supercharging of the oligosaccharide ions increased their signal strengths relative to controls. Tandem MS of these supercharged precursor ions showed decreased abundances of product ions from sulfate losses yet more abundant product ions from backbone cleavages.
Marcó, Sara; Pujol, Anna; Roca, Carles; Motas, Sandra; Ribera, Albert; Garcia, Miguel; Molas, Maria; Villacampa, Pilar; Melia, Cristian S.; Sánchez, Víctor; Sánchez, Xavier; Bertolin, Joan; Ruberte, Jesús; Haurigot, Virginia
2016-01-01
ABSTRACT Mucopolysaccharidosis type IIIC (MPSIIIC) is a severe lysosomal storage disease caused by deficiency in activity of the transmembrane enzyme heparan-α-glucosaminide N-acetyltransferase (HGSNAT) that catalyses the N-acetylation of α-glucosamine residues of heparan sulfate. Enzyme deficiency causes abnormal substrate accumulation in lysosomes, leading to progressive and severe neurodegeneration, somatic pathology and early death. There is no cure for MPSIIIC, and development of new therapies is challenging because of the unfeasibility of cross-correction. In this study, we generated a new mouse model of MPSIIIC by targeted disruption of the Hgsnat gene. Successful targeting left LacZ expression under control of the Hgsnat promoter, allowing investigation into sites of endogenous expression, which was particularly prominent in the CNS, but was also detectable in peripheral organs. Signs of CNS storage pathology, including glycosaminoglycan accumulation, lysosomal distension, lysosomal dysfunction and neuroinflammation were detected in 2-month-old animals and progressed with age. Glycosaminoglycan accumulation and ultrastructural changes were also observed in most somatic organs, but lysosomal pathology seemed most severe in liver. Furthermore, HGSNAT-deficient mice had altered locomotor and exploratory activity and shortened lifespan. Hence, this animal model recapitulates human MPSIIIC and provides a useful tool for the study of disease physiopathology and the development of new therapeutic approaches. PMID:27491071
Mosulén, Silvia; Ortí, Leticia; Bas, Esperanza; Carbajo, Rodrigo J; Pineda-Lucena, Antonio
2011-02-01
Heparanase is an endo-β-D-glucosidase capable of specifically degrading heparan sulphate, one of the main components of the extracellular matrix. This 65 kDa polypeptide is implicated in cancer processes such as tumour formation, angiogenesis and metastasis, making it a very attractive target in antitumour treatments. Structure-based approaches to find inhibitors of heparanase have been historically hampered by the lack of success in crystallizing the protein. With the aim to undertake the NMR structural characterisation of heparanase, we have designed and produced, using recombinant methods, smaller constructs of heparanase containing the catalytically active glutamic acids and the two binding sites for heparan sulphate. An extensive range of expression and purification conditions were evaluated to alleviate the intrinsic low solubility and aggregation propensity of heparanase, allowing the obtention of the enzyme in milligram quantities, both unlabelled and ¹⁵N-labelled for NMR studies. Using the smallest of the designed constructs and applying NMR and SPR methodologies, we have demonstrated that known inhibitors of heparanase bind to this construct specifically and selectively with K(D) values in the range of those reported for human heparanase, validating it for future drug discovery projects focused on the identification of novel inhibitors of this enzyme. © 2010 Wiley Periodicals, Inc.
Rusnati, Marco; Oreste, Pasqua; Zoppetti, Giorgio; Presta, Marco
2005-01-01
Heparin is a sulphated glycosaminoglycan currently used as an anticoagulant and antithrombotic drug. It consists largely of 2-O-sulphated IdoA not l&r arrow N, 6-O-disulphated GlcN disaccharide units. Other disaccharides containing unsulphated IdoA or GlcA and N-sulphated or N-acetylated GlcN are also present as minor components. This heterogeneity is more pronounced in heparan sulphate (HS), where the low-sulphated disaccharides are the most abundant. Heparin/HS bind to a variety of biologically active polypeptides, including enzymes, growth factors and cytokines, and viral proteins. This capacity can be exploited to design multi-target heparin/HS-derived drugs for pharmacological interventions in a variety of pathologic conditions besides coagulation and thrombosis, including neoplasia and viral infection. The capsular K5 polysaccharide from Escherichia coli has the same structure as the heparin precursor N-acetyl heparosan. The possibility of producing K5 polysaccharide derivatives by chemical and enzymatic modifications, thus generating heparin/HS-like compounds, has been demonstrated. These K5 polysaccharide derivatives are endowed with different biological properties, including anticoagulant/antithrombotic, antineoplastic, and anti-AIDS activities. Here, the literature data are discussed and the possible therapeutic implications for this novel class of multi-target "biotechnological heparin/HS" molecules are outlined.
Zhang, Xu; Wang, Fengshan; Sheng, Juzheng
2016-06-16
Heparan sulfate (HS) is widely distributed in mammalian tissues in the form of HS proteoglycans, which play essential roles in various physiological and pathological processes. In contrast to the template-guided processes involved in the synthesis of DNA and proteins, HS biosynthesis is not believed to involve a template. However, it appears that the final structure of HS chains was strictly regulated. Herein, we report research based hypothesis that two major steps, namely "coding" and "decoding" steps, are involved in the biosynthesis of HS, which strictly regulate its chemical structure and biological activity. The "coding" process in this context is based on the distribution of sulfate moieties on the amino groups of the glucosamine residues in the HS chains. The sulfation of these amine groups is catalyzed by N-deacetylase/N-sulfotransferase, which has four isozymes. The composition and distribution of sulfate groups and iduronic acid residues on the glycan chains of HS are determined by several other modification enzymes, which can recognize these coding sequences (i.e., the "decoding" process). The degree and pattern of the sulfation and epimerization in the HS chains determines the extent of their interactions with several different protein factors, which further influences their biological activity. Copyright © 2016 Elsevier Ltd. All rights reserved.
Profiling Heparin-Chemokine Interactions Using Synthetic Tools
de Paz, Jose L.; Moseman, E. Ashley; Noti, Christian; Polito, Laura; von Andrian, Ulrich H.; Seeberger, Peter H.
2009-01-01
Glycosaminoglycans (GAGs), such as heparin or heparan sulfate, are required for the in vivo function of chemokines. Chemokines play a crucial role in the recruitment of leukocyte subsets to sites of inflammation and lymphocytes trafficking. GAG-chemokine interactions mediate cell migration and determine which leukocyte subsets enter tissues. Identifying the exact GAC sequences that bind to particular chemokines is key to understand chemokine function at the molecular level and develop strategies to interfere with chemokine-mediated processes. Here, we characterize the heparin binding profiles of eight chemokines (CCL21, IL-8, CXCL12, CXCL13, CCL19, CCL25, CCL28, and CXCL16) by employing heparin microarrays containing a small library of synthetic heparin oligosaccharides. The chemokines differ significantly in their interactions with heparin oligosaccharides: While some chemokines, (e.g., CCL21) strongly bind to a hexasaccharide containing the GlcNSO3(6-OSO3)-IdoA(2-OSO3) repeating unit, CCL19 does not bind and CXCL12 binds only weakly. The carbohydrate microarray binding results were validated by surface plasmon resonance experiments. In vitro chemotaxis assays revealed that dendrimers coated with the fully sulfated heparin hexasaccharide inhibit lymphocyte migration toward CCL21. Migration toward CXCL12 or CCL19 was not affected. These in vitro homing assays indicate that multivalent synthetic heparin dendrimers inhibit the migration of lymphocytes toward certain chemokine gradients by blocking the formation of a chemokine concentration gradient on GAG endothelial chains. These findings are in agreement with preliminary in vivo measurements of circulating lymphocytes. The results presented here contribute to the understanding of GAG-chemokine interactions, a first step toward the design of novel drugs that modulate chemokine activity. PMID:18030990
Ostrovsky, Olga; Korostishevsky, Michael; Shafat, Itay; Mayorov, Margarita; Ilan, Neta; Vlodavsky, Israel; Nagler, Arnon
2009-01-01
Heparanase is an endo-β-glucuronidase that specifically cleaves the saccharide chains of heparan sulfate proteoglycans. Heparanase plays important roles in processes such as angiogenesis, tumor metastasis, tissue repair and remodeling, inflammation and autoimmunity. Genetic variations of the heparanase gene (HPSE) have been associated with heparanase transcription level. The present study was undertaken to identify haplotype or single nucleotide polymorphisms (SNPs) genotype combinations that correlate with heparanase expression both at the mRNA and protein levels. For this purpose, 11 HPSE gene SNPs were genotyped among 108 healthy individuals. Five out of the eleven polymorphisms revealed an association between the SNPs and heparanase expression. SNP rs4693608 exhibited a strong evidence of association. Analysis of haplotypes distribution revealed that the combination of two SNPs (rs4693608 and rs4364254) disclosed the most significant result. This approach allowed segregation of possible genotype combinations to three groups that correlate with low (LR: GG-CC, GG-CT, GG-TT, GA-CC), intermediate (MR: GA-CT, GA-TT) and high (HR: AA-TT, AA-CT) heparanase expression. Unexpectedly, LR genotype combinations were associated with low mRNA expressions level and high heparanase concentration in plasma, while HR genotype combinations were associated with high expression of mRNA and low plasma protein level. Because the main site of activity of secreted active heparanase is the extracellular matrix and cell surface, the origin and functional significance of plasma heparanase remain to be investigated. The current study indicates that rs4693608 and rs4364254 SNPs are involved in the regulation of heparanase expression and provides the basis for further studies on the association between HPSE gene SNPs and disease outcome. PMID:19406828
Mason, Roger M
2013-01-01
Connective tissue growth factor (CTGF, CCN2) is a member of the CCN family of matricellular proteins. It interacts with many other proteins, including plasma membrane proteins, modulating cell function. It is expressed at low levels in normal adult kidney cells but is increased in kidney diseases, playing important roles in inflammation and in the development of glomerular and interstitial fibrosis in chronic disease. This review reports the evidence for its expression in human and animal models of chronic kidney disease and summarizes data showing that anti-CTGF therapy can successfully attenuate fibrotic changes in several such models, suggesting that therapies targeting CTGF and events downstream of it in renal cells may be useful for the treatment of human kidney fibrosis. Connective tissue growth factor stimulates the development of fibrosis in the kidney in many ways including activating cells to increase extracellular matrix synthesis, inducing cell cycle arrest and hypertrophy, and prolonging survival of activated cells. The relationship between CTGF and the pro-fibrotic factor TGFβ is examined and mechanisms by which CTGF promotes signalling by the latter are discussed. No specific cellular receptors for CTGF have been discovered but it interacts with and activates several plasma membrane proteins including low-density lipoprotein receptor-related protein (LRP)-1, LRP-6, tropomyosin-related kinase A, integrins and heparan sulphate proteoglycans. Intracellular signalling and downstream events triggered by such interactions are reviewed. Finally, the relationships between CTGF and several anti-fibrotic factors, such as bone morphogenetic factor-4 (BMP4), BMP7, hepatocyte growth factor, CCN3 and Oncostatin M, are discussed. These may determine whether injured tissue heals or progresses to fibrosis. PMID:23110747
Blois, Sandra M; Tirado-González, Irene; Wu, Julie; Barrientos, Gabriela; Johnson, Briana; Warren, James; Freitag, Nancy; Klapp, Burghard F; Irmak, Ster; Ergun, Suleyman; Dveskler, Gabriela S
2012-06-01
Mouse and human pregnancy-specific glycoproteins (PSG) are known to exert immunomodulatory functions during pregnancy by inducing maternal leukocytes to secrete anti-inflammatory cytokines that promote a tolerogenic decidual microenvironment. Many such anti-inflammatory mediators also function as proangiogenic factors, which, along with the reported association of murine PSG with the uterine vasculature, suggest that PSG may contribute to the vascular adaptations necessary for successful implantation and placental development. We observed that PSG22 is strongly expressed around the embryonic crypt on Gestation Day 5.5, indicating that trophoblast giant cells are the main source of PSG22 during the early stages of pregnancy. PSG22 treatment up-regulated the secretion of transforming growth factor beta 1 and vascular endothelial growth factor A (VEGFA) in murine macrophages, uterine dendritic cells, and natural killer cells. A possible role of PSGs in uteroplacental angiogenesis is further supported by the finding that incubation of endothelial cells with PSG22 resulted in the formation of tubes in the presence and absence of VEGFA. We determined that PSG22, like human PSG1 and murine PSG17 and PSG23, binds to the heparan sulfate chains in syndecans. Therefore, our findings indicate that despite the independent evolution and expansion of human and rodent PSG, members in both families have conserved functions that include their ability to induce anti-inflammatory cytokines and proangiogenic factors as well as to induce the formation of capillary structures by endothelial cells. In summary, our results indicate that PSG22, the most abundant PSG expressed during mouse early pregnancy, is likely a major contributor to the establishment of a successful pregnancy.
Berryman, Stephen; Clark, Stuart; Kakker, Naresh K.; Silk, Rhiannon; Seago, Julian; Wadsworth, Jemma; Chamberlain, Kyle; Knowles, Nick J.
2013-01-01
Field isolates of foot-and-mouth disease virus (FMDV) have a restricted cell tropism which is limited by the need for certain RGD-dependent integrin receptors. In contrast, cell culture-adapted viruses use heparan sulfate (HS) or other unidentified molecules as receptors to initiate infection. Here, we report several novel findings resulting from cell culture adaptation of FMDV. In cell culture, a virus with the capsid of the A/Turkey/2/2006 field isolate gained the ability to infect CHO and HS-deficient CHO cells as a result of a single glutamine (Q)-to-lysine (K) substitution at VP1-110 (VP1-Q110K). Using site-directed mutagenesis, the introduction of lysine at this same site also resulted in an acquired ability to infect CHO cells by type O and Asia-1 FMDV. However, this ability appeared to require a second positively charged residue at VP1-109. CHO cells express two RGD-binding integrins (α5β1 and αvβ5) that, although not used by FMDV, have the potential to be used as receptors; however, viruses with the VP1-Q110K substitution did not use these integrins. In contrast, the VP1-Q110K substitution appeared to result in enhanced interactions with αvβ6, which allowed a virus with KGE in place of the normal RGD integrin-binding motif to use αvβ6 as a receptor. Thus, our results confirmed the existence of nonintegrin, non-HS receptors for FMDV on CHO cells and revealed a novel, non-RGD-dependent use of αvβ6 as a receptor. The introduction of lysine at VP1-110 may allow for cell culture adaptation of FMDV by design, which may prove useful for vaccine manufacture when cell culture adaptation proves intractable. PMID:23740982
Szewczyk, Michal; Drzewinska, Joanna; Dzmitruk, Volha; Shcharbin, Dzmitry; Klajnert, Barbara; Appelhans, Dietmar; Bryszewska, Maria
2012-12-20
There are several barriers to the application of dendriplexes formed by poly(propylene imine) dendrimers and genetic material for gene therapy. One limitation is their interaction with extracellular matrix components such as glucosaminoglycans. These can displace the genetic material from the dendriplexes, affecting their transfection activity. In this study, we analyzed the interaction between dendriplexes and the four main glucosaminoglycans (heparin, heparan sulfate, chondroitin sulfate, and hyaluronic acid) by fluorescence polarization and gel electrophoresis. Dendriplexes were formed by combining three anti-HIV antisense oligodeoxynucleotides with three poly(propylene imine) dendrimers of the fourth generation: unmodified and partially modified with maltose and maltotriose (open shell glycodendrimers). The data showed that the effect of glucosaminoglycans on dendriplexes depends on the glucosaminoglycan type and the oligosaccharide serving as the surface group of the dendrimer. Heparin at physiological concentrations destroys dendriplexes formed by open shell glycodendrimers, but dendriplexes based on unmodified poly(propylene imine) dendrimers are stable in its presence. The other glucosaminoglycans at physiological concentrations cannot destroy dendriplexes formed by any of the dendrimers studied.
Heparanase and macrophage interplay in the onset of liver fibrosis.
Secchi, Maria Francesca; Crescenzi, Marika; Masola, Valentina; Russo, Francesco Paolo; Floreani, Annarosa; Onisto, Maurizio
2017-11-02
The heparan sulfate endoglycosidase heparanase (HPSE) is involved in tumor growth, chronic inflammation and fibrosis. Since a role for HPSE in chronic liver disease has not been demonstrated to date, the current study was aimed at investigating the involvement of HPSE in the pathogenesis of chronic liver injury. Herein, we revealed that HPSE expression increased in mouse livers after carbon tetrachloride (CCl 4 )-mediated chronic induction of fibrosis, but with a trend to decline during progression of the disease. In mouse fibrotic liver tissues HPSE immunostaining was restricted in necro-inflammatory areas, co-localizing with F4/80 macrophage marker and TNF-α. TNF-α treatment induced HPSE expression as well as HPSE secretion in U937 macrophages. Moreover, macrophage-secreted HPSE regulated the expression of α-SMA and fibronectin in hepatic stellate LX-2 cells. Finally, HPSE activity increased in the plasma of patients with liver fibrosis but it inversely correlated with liver stiffness. Our results suggest the involvement of HPSE in early phases of reaction to liver damage and inflammatory macrophages as an important source of HPSE. HPSE seems to play a key role in the macrophage-mediated activation of hepatic stellate cells (HSCs), thus suggesting that HPSE targeting could be a new therapeutic option in the treatment of liver fibrosis.
Binding of perlecan to transthyretin in vitro.
Smeland, S; Kolset, S O; Lyon, M; Norum, K R; Blomhoff, R
1997-01-01
Transthyretin is one of two specific proteins involved in the transport of thyroid hormones in plasma; it possesses two binding sites for serum retinol-binding protein. In the present study we demonstrate that transthyretin also interacts in vitro with [35S]sulphate-labelled material from the medium of HepG2 cells. By using the same strategy as for purifying serum retinol-binding protein, [35S]sulphate-labelled medium was specifically eluted from a transthyretin-affinity column. Ion-exchange chromatography showed that the material was highly polyanionic, and its size and alkali susceptibility suggested that it was a proteoglycan. Structural analyses with chondroitinase ABC lyase and nitrous acid revealed that approx. 20% was chondroitin sulphate and 80% heparan sulphate. Immunoprecipitation showed that the [35S]sulphate-labelled material contained perlecan. Further analysis by binding studies revealed specific and saturable binding of 125I-transthyretin to perlecan-enriched Matrigel. Because inhibition of sulphation by treating HepG2 cells with sodium chlorate increased the affinity of the perlecan for transthyretin, and [3H]heparin was not retained by the transthyretin affinity column, the binding is probably mediated by the core protein and is not a protein-glycosaminoglycan interaction. Because perlecan is released from transthyretin in water, the binding might be due to hydrophobic interactions. PMID:9307034
NASA Astrophysics Data System (ADS)
Jimenez Vergara, Andrea Carolina
Tissue engineering (TE) approaches have emerged as an alternative to traditional tissue and organ replacements. The aim of this work was to contribute to the understanding of the effects of cell-material and endothelial cell (EC) paracrine signaling on cell responses using poly(ethylene glycol) diacrylate (PEGDA) hydrogels as a material platform. Three TE applications were explored. First, the effect of glycosaminoglycan (GAG) identity was evaluated for vocal fold restoration. Second, the influence of GAG identity was explored and a novel approach for stable endothelialization was developed for vascular graft applications. Finally, EC paracrine signaling in the presence of cyclic stretch, and hydrophobicity and inorganic content were studied for osteogenic applications. In terms of vocal fold restoration, it was found that vocal fold fibroblast (VFF) phenotype and extracellular matrix (ECM) production were impacted by GAG identity. VFF phenotype was preserved in long-term cultured hydrogels containing high molecular weight hyaluronan (HAHMW). Furthermore, collagen I deposition, fibronectin production and smooth muscle α-actin (SM-α-actin) expression in PEG-HA, PEG-chondroitin sulfate C and PEG-heparan sulfate (HS) gels suggest that CSC and HS may be undesirable for vocal fold implants. Regarding vascular graft applications, the impact of GAG identity on smooth muscle cell (SMC) foam cell formation was explored. Results support the increasing body of literature that suggests a critical role for dermatan sulfate (DS)-bearing proteoglycans in early atherosclerosis. In addition, an approach for fabricating bi-layered tissue engineering vascular grafts (TEVGs) with stable endothelialization was validated using PEGDA as an intercellular “cementing” agent between adjacent endothelial cells (ECs). Finally, mesenchymal stem cell (MSC) differentiation toward osteogenic like cells was evaluated. ECM and cell phenotypic data showed that elevated scaffold inorganic content and hydrophobicity were indeed correlated with increased osteogenic differentiation. Moreover, the present results suggest that EC paracrine signaling enhances MSC osteogenesis in the presence of cyclic stretch.
Sharpe, Benjamin; Alghezi, Dhafer A; Cattermole, Claire; Beresford, Mark; Bowen, Rebecca; Mitchard, John; Chalmers, Andrew D
2017-05-01
There is a pressing need to identify prognostic and predictive biomarkers for prostate cancer to aid treatment decisions in both early and advanced disease settings. Syndecan-1, a heparan sulfate proteoglycan, has been previously identified as a potential prognostic biomarker by multiple studies at the tissue and serum level. However, other studies have questioned its utility. Anti-Syndecan-1 immunohistochemistry was carried out on 157 prostate tissue samples (including cancerous, adjacent normal tissue, and non-diseased prostate) from three independent cohorts of patients. A population of Syndecan-1 positive stromal cells was identified and the number and morphological parameters of these cells quantified. The identity of the Syndecan-1-positive stromal cells was assessed by multiplex immunofluorescence using a range of common cell lineage markers. Finally, the burden of Syndecan-1 positive stromal cells was tested for association with clinical parameters. We identified a previously unreported cell type which is marked by Syndecan-1 expression and is found in the stroma of prostate tumors and adjacent normal tissue but not in non-diseased prostate. We call these cells Prostate Cancer Syndecan-1 Positive (PCSP) cells. Immunofluorescence analysis revealed that the PCSP cell population did not co-stain with markers of common prostate epithelial, stromal, or immune cell populations. However, morphological analysis revealed that PCSP cells are often elongated and displayed prominent lamellipodia, suggesting they are an unidentified migratory cell population. Analysis of clinical parameters showed that PCSP cells were found with a frequency of 20-35% of all tumors evaluated, but were not present in non-diseased normal tissue. Interestingly, a subset of primary Gleason 5 prostate tumors had a high burden of PCSP cells. The current study identifies PCSP cells as a novel, potentially migratory cell type, which is marked by Syndecan-1 expression and is found in the stroma of prostate carcinomas, adjacent normal tissue, but not in non-diseased prostate. A subset of poor prognosis high Gleason grade 5 tumors had a particularly high PCSP cell burden, suggesting an association between this unidentified cell type and tumor aggressiveness. © 2017 Wiley Periodicals, Inc.
Heparanase augments insulin receptor signaling in breast carcinoma
Goldberg, Rachel; Sonnenblick, Amir; Hermano, Esther; Hamburger, Tamar; Meirovitz, Amichay; Peretz, Tamar; Elkin, Michael
2017-01-01
Recently, growing interest in the potential link between metabolic disorders (i.e., diabetes, obesity, metabolic syndrome) and breast cancer has mounted, including studies which indicate that diabetic/hyperinsulinemic women have a significantly higher risk of bearing breast tumors that are more aggressive and associated with higher death rates. Insulin signaling is regarded as a major contributor to this phenomenon; much less is known about the role of heparan sulfate-degrading enzyme heparanase in the link between metabolic disorders and cancer. In the present study we analyzed clinical samples of breast carcinoma derived from diabetic/non-diabetic patients, and investigated effects of heparanase on insulin signaling in breast carcinoma cell lines, as well as insulin-driven growth of breast tumor cells. We demonstrate that heparanase activity leads to enhanced insulin signaling and activation of downstream tumor-promoting pathways in breast carcinoma cells. In agreement, heparanase enhances insulin-induced proliferation of breast tumor cells in vitro. Moreover, analyzing clinical data from diabetic breast carcinoma patients, we found that concurrent presence of both diabetic state and heparanase in tumor tissue (as opposed to either condition alone) was associated with more aggressive phenotype of breast tumors in the patient cohort analyzed in our study (two-sided Fisher's exact test; p=0.04). Our findings highlight the emerging role of heparanase in powering effect of hyperinsulinemic state on breast tumorigenesis and imply that heparanase targeting, which is now under intensive development/clinical testing, could be particularly efficient in a growing fraction of breast carcinoma patients suffering from metabolic disorders. PMID:28038446
Evaluation of Disease Lesions in the Developing Canine MPS IIIA Brain.
Winner, Leanne K; Marshall, Neil R; Jolly, Robert D; Trim, Paul J; Duplock, Stephen K; Snel, Marten F; Hemsley, Kim M
2018-06-20
Mucopolysaccharidosis IIIA (MPS IIIA) is an inherited neurodegenerative disease of childhood that results in early death. Post-mortem studies have been carried out on human MPS IIIA brain, but little is known about early disease development. Here, we utilised the Huntaway dog model of MPS IIIA to evaluate disease lesion development from 2 to 24 weeks of age. A significant elevation in primarily stored heparan sulphate was observed in all brain regions assessed in MPS IIIA pups ≤9.5 weeks of age. There was a significant elevation in secondarily stored ganglioside (GM3 36:1) in ≤9.5-week-old MPS IIIA pup cerebellum, and other brain regions also exhibited accumulation of this lipid with time. The number of neural stem cells and neuronal precursor cells was essentially unchanged in MPS IIIA dog brain (c.f. unaffected) over the time course assessed, a finding corroborated by neuron cell counts. We observed early neuroinflammatory changes in young MPS IIIA pup brain, with significantly increased numbers of activated microglia recorded in all but one brain region in MPS IIIA pups ≤9.5 weeks of age (c.f. age-matched unaffected pups). In conclusion, infant-paediatric-stage MPS IIIA canine brain exhibits substantial and progressive primary and secondary substrate accumulation, coupled with early and robust microgliosis. Whilst early initiation of treatment is likely to be required to maintain optimal neurological function, the brain's neurodevelopmental potential appears largely unaffected by the disease process; further investigations confirming this are warranted.
Gziut, M; MacGregor, HJ; Nevell, TG; Mason, T; Laight, D; Shute, JK
2013-01-01
Background and Purpose Airway inflammation in cystic fibrosis (CF) patients is characterized by accumulations of neutrophils in the airway and T cells in bronchial tissue, with activation of platelets in the circulation. CF patients are routinely treated with systemic or inhaled tobramycin for airway infection with Pseudomonas aeruginosa. Clinical trials have indicated an anti-inflammatory effect of tobramycin beyond its bactericidal activity. Here, we investigate the anti-inflammatory properties of tobramycin in vitro and consider if these relate to the ability of tobramycin to bind copper, which is elevated in blood and sputum in CF. Experimental Approach A copper–tobramycin complex was synthesized. The effect of tobramycin and copper–tobramycin on neutrophil activation and migration of T cells and neutrophils across human lung microvascular endothelial cells in response to thrombin-activated platelets were investigated in vitro. Tobramycin uptake was detected by immunocytochemistry. Intracellular reactive oxygen species were detected using the fluorescent indicator, 2′,7′-dichlorofluorescein diacetate (DCFDA). Neutrophil superoxide, hydrogen peroxide and neutrophil elastase activity were measured using specific substrates. Copper was measured using atomic absorption spectroscopy. Key Results Tobramycin and copper–tobramycin were taken up by endothelial cells via a heparan sulphate-dependent mechanism and significantly inhibited T-cell and neutrophil transendothelial migration respectively. Copper–tobramycin has intracellular and extracellular superoxide dismutase-like activity. Neutrophil elastase inhibition by α1-antitrypsin is enhanced in the presence of copper–tobramycin. Tobramycin and copper–tobramycin are equally effective anti-pseudomonal antibiotics. Conclusions and Implications Anti-inflammatory effects of tobramycin in vivo may relate to the spontaneous formation of a copper–tobramycin complex, implying that copper–tobramycin may be more effective therapy. PMID:23072509
Hu, Yunping; Sun, Haiguo; Owens, Rick T; Gu, Zhennan; Wu, Jansheng; Chen, Yong Q; O'Flaherty, Joseph T; Edwards, Iris J
2010-01-01
Evidence indicates that diets enriched in n-3 polyunsaturated fatty acids (n-3 PUFAs) reduce the risk of prostate cancer, but biochemical mechanisms are unclear. Syndecan-1 (SDC-1), a transmembrane heparan sulfate proteoglycan, supports the integrity of the epithelial compartment. In tumor cells of epithelial lineage, SDC-1 is generally downregulated. This may result in perturbation of homeostasis and lead to progression of malignancy. Our studies have shown that the n-3 PUFA species, docosahexaenoic acid (DHA), increases SDC-1 expression in prostate tissues of Pten knockout (PtenP-/-) mice/cells and human prostate cancer cells. We have now determined that DHA-mediated up-regulation of SDC-1 induces apoptosis. Bovine serum albumin-bound DHA and exogenous human recombinant SDC-1 ecotodomain were delivered to PC3 and LNCaP cells in the presence or absence of SDC-1 small interfering (si)RNA. In the presence of control siRNA, both DHA and SDC-1 ectodomain induced apoptosis, whereas SDC-1 silencing blocked DHA-induced but not SDC-1 ectodomain-induced apoptosis. Downstream effectors of SDC-1 signaling linked to n-3 PUFA-induced apoptosis involved the 3′-phosphoinositide-dependent kinase 1 (PDK1)/Akt/Bad integrating network. A diet enriched in n-3 PUFA decreased phosphorylation of PDK1, Akt (T308), and Bad in prostates of PtenP-/- mice. Similar results were observed in human prostate cancer cells in response to DHA and SDC-1 ectodomain. The effect of DHA on PDK1/Akt/Bad signaling was abrogated by SDC-1 siRNA. These findings define a mechanism by which SDC-1-dependent suppression of phosphorylation of PDK1/Akt/Bad mediates n-3 PUFA-induced apoptosis in prostate cancer. PMID:20927321
Alport syndrome and Pierson syndrome: Diseases of the glomerular basement membrane.
Funk, Steven D; Lin, Meei-Hua; Miner, Jeffrey H
2018-04-16
The glomerular basement membrane (GBM) is an important component of the kidney's glomerular filtration barrier. Like all basement membranes, the GBM contains type IV collagen, laminin, nidogen, and heparan sulfate proteoglycan. It is flanked by the podocytes and glomerular endothelial cells that both synthesize it and adhere to it. Mutations that affect the GBM's collagen α3α4α5(IV) components cause Alport syndrome (kidney disease with variable ear and eye defects) and its variants, including thin basement membrane nephropathy. Mutations in LAMB2 that impact the synthesis or function of laminin α5β2γ1 (LM-521) cause Pierson syndrome (congenital nephrotic syndrome with eye and neurological defects) and its less severe variants, including isolated congenital nephrotic syndrome. The very different types of kidney diseases that result from mutations in collagen IV vs. laminin are likely due to very different pathogenic mechanisms. A better understanding of these mechanisms should lead to targeted therapeutic approaches that can help people with these rare but important diseases. Copyright © 2017 International Society of Matrix Biology. Published by Elsevier B.V. All rights reserved.
Hexagonal-shaped chondroitin sulfate self-assemblies have exalted anti-HSV-2 activity.
Galus, Aurélia; Mallet, Jean-Maurice; Lembo, David; Cagno, Valeria; Djabourov, Madeleine; Lortat-Jacob, Hugues; Bouchemal, Kawthar
2016-01-20
The initial step in mucosal infection by the herpes simplex virus type 2 (HSV-2) requires its binding to certain glycosaminoglycans naturally present on host cell membranes. We took advantage of this interaction to design biomimetic supramolecular hexagonal-shaped nanoassemblies composed of chondroitin sulfate having exalted anti-HSV-2 activity in comparison with native chondroitin sulfate. Nanoassemblies were formed by mixing hydrophobically-modified chondroitin sulfate with α-cyclodextrin in water. Optimization of alkyl chain length grafted on chondroitin sulfate and the ratio between hydrophobically-modified chondroitin sulfate and α-cyclodextrin showed that more cohesive and well-structured nanoassemblies were obtained using higher α-cyclodextrin concentration and longer alkyl chain lengths. A structure-activity relationship was found between anti-HSV-2 activity and the amphiphilic nature of hydrophobically-modified chondroitin sulfate. Also, antiviral activity of hexagonal nanoassemblies against HSV-2 was further improved in comparison with hydrophobically-modified chondroitin sulfate. This work suggests a new biomimetic formulation approach that can be extended to other heparan-sulfate-dependent viruses. Copyright © 2015 Elsevier Ltd. All rights reserved.
Chang, Yuqing; Yang, Bo; Zhao, Xue; Linhardt, Robert J.
2012-01-01
A quantitative and highly sensitive method for the analysis of glycosaminoglycan (GAG)-derived disaccharides is presented that relies on capillary electrophoresis (CE) with laser-induced fluorescence (LIF) detection. This method enables complete separation of seventeen GAG-derived disaccharides in a single run. Unsaturated disaccharides were derivatized with 2-aminoacridone (AMAC) to improve sensitivity. The limit of detection was at the attomole level and about 100-fold more sensitive than traditional CE-ultraviolet detection. A CE separation timetable was developed to achieve complete resolution and shorten analysis time. The RSD of migration time and peak areas at both low and high concentrations of unsaturated disaccharides are all less than 2.7% and 3.2%, respectively, demonstrating that this is a reproducible method. This analysis was successfully applied to cultured Chinese hamster ovary cell samples for determination of GAG disaccharides. The current method simplifies GAG extraction steps, and reduces inaccuracy in calculating ratios of heparin/heparan sulfate to chondroitin sulfate/dermatan sulfate, resulting from the separate analyses of a single sample. PMID:22609076
Interaction of PF4 (CXCL4) with the vasculature: a role in atherosclerosis and angiogenesis.
Aidoudi, Sallouha; Bikfalvi, Andreas
2010-11-01
Platelet factor-4 (PF4), a platelet-derived chemokine, has two important functions in the vasculature. It has a pro-atherogenic role while also having anti-angiogenic effects. The activity of platelet factor-4 (PF4), unlike other chemokines that bind to specific receptors, depends on its unusually high affinity for proteoglycans and other negatively charged molecules. High affinity for heparan sulfates was thought to be central to all of PF4's biological functions. However, other mechanisms have been described such as direct growth factor binding, activation of the CXCR3B chemokine receptor isoform that is present in some vascular cells or binding to lipoprotein-related protein-1 (LRP1). Furthermore, PF4 also binds to integrins with affinities similar to matrix molecules. These interactions may explain the effects of PF4 in healthy and pathological tissues. However, the mechanisms involved in PF4's activity are complex and may depend on a given tissue or localisation. Overall, while much is already known about PF4, its specific role in atherosclerosis and angiogenesis remains still to be clarified.
Galeotti, Fabio; Volpi, Nicola
2011-09-01
A high-resolution online reverse-phase-high-performance liquid chromatography (RP-HPLC)-fluorescence detector (Fd)-electrospray ionization-mass spectrometry (ESI-MS) separation and structural characterization of disaccharides prepared from heparin (Hep), heparan sulfate (HS), and various low-molecular-weight (LMW)-Hep using heparin lyases and derivatization with 2-aminoacridone (AMAC) are described. A total of 12 commercially available Hep/HS-derived unsaturated disaccharides were separated and unambiguously identified on the basis of their retention times and mass spectra. The constituent disaccharides of various samples, including unfractionated Hep/HS, fast-moving and slow-moving Hep components, and several marketed products, were characterized. Furthermore, for the first time, the saturated trisulfated disaccharide belonging to the nonreducing end of Heps was detected as being approximately 2% in unfractionated samples and ~15-21% in LMW-Heps prepared by nitrous acid depolymerization. No desalting of the commercial products prior to enzymatic digestion or prepurification steps to eliminate any excess of AMAC reagent or interference from proteins, peptides, and other sample impurities before RP-HPLC-Fd-ESI-MS injection were necessary. This method has applicability for the rapid differentiation of pharmaceutical Heps and LMW-Heps prepared by means of different depolymerization processes and for compositional analysis of small amounts of samples derived from biological sources by using the highly sensitive fluorescence detector.
Marcó, Sara; Pujol, Anna; Roca, Carles; Motas, Sandra; Ribera, Albert; Garcia, Miguel; Molas, Maria; Villacampa, Pilar; Melia, Cristian S; Sánchez, Víctor; Sánchez, Xavier; Bertolin, Joan; Ruberte, Jesús; Haurigot, Virginia; Bosch, Fatima
2016-09-01
Mucopolysaccharidosis type IIIC (MPSIIIC) is a severe lysosomal storage disease caused by deficiency in activity of the transmembrane enzyme heparan-α-glucosaminide N-acetyltransferase (HGSNAT) that catalyses the N-acetylation of α-glucosamine residues of heparan sulfate. Enzyme deficiency causes abnormal substrate accumulation in lysosomes, leading to progressive and severe neurodegeneration, somatic pathology and early death. There is no cure for MPSIIIC, and development of new therapies is challenging because of the unfeasibility of cross-correction. In this study, we generated a new mouse model of MPSIIIC by targeted disruption of the Hgsnat gene. Successful targeting left LacZ expression under control of the Hgsnat promoter, allowing investigation into sites of endogenous expression, which was particularly prominent in the CNS, but was also detectable in peripheral organs. Signs of CNS storage pathology, including glycosaminoglycan accumulation, lysosomal distension, lysosomal dysfunction and neuroinflammation were detected in 2-month-old animals and progressed with age. Glycosaminoglycan accumulation and ultrastructural changes were also observed in most somatic organs, but lysosomal pathology seemed most severe in liver. Furthermore, HGSNAT-deficient mice had altered locomotor and exploratory activity and shortened lifespan. Hence, this animal model recapitulates human MPSIIIC and provides a useful tool for the study of disease physiopathology and the development of new therapeutic approaches. © 2016. Published by The Company of Biologists Ltd.
Strunz, Célia Maria Cássaro; Roggerio, Alessandra; Cruz, Paula Lázara; Pacanaro, Ana Paula; Salemi, Vera Maria Cury; Benvenuti, Luiz Alberto; Mansur, Antonio de Pádua; Irigoyen, Maria Cláudia
2017-02-01
Cardiac remodeling in diabetes involves cardiac hypertrophy and fibrosis, and fibroblast growth factor 2 (FGF2) is an important mediator of this process. Resveratrol, a polyphenolic antioxidant, reportedly promotes the improvement of cardiac dysfunction in diabetic rats. However, little information exists linking the amelioration of the cardiac function promoted by resveratrol and the expression of FGF2 and its co-receptors, heparan sulfate proteoglycans (HSPGs: Glypican-1 and Syndecan-4), in cardiac muscle of Type 2 diabetic rats. Diabetes was induced experimentally by the injection of streptozotocin and nicotinamide, and the rats were treated with resveratrol for 6 weeks. According to our results, there is an up-regulation of the expression of genes and/or proteins of Glypican-1, Syndecan-4, FGF2, peroxisome proliferator-activated receptor gamma and AMP-activated protein kinase in diabetic rats. On the other hand, resveratrol treatment promoted the attenuation of left ventricular diastolic dysfunction and the down-regulation of the expression of all proteins under study. The trigger for the changes in gene expression and protein synthesis promoted by resveratrol was the presence of diabetes. The negative modulation conducted by resveratrol on FGF2 and HSPGs expression, which are involved in cardiac remodeling, underlies the amelioration of cardiac function. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.
Won, Seoung Youn; Kim, Cha Yeon; Kim, Doyoun; Ko, Jaewon; Um, Ji Won; Lee, Sung Bae; Buck, Matthias; Kim, Eunjoon; Heo, Won Do; Lee, Jie-Oh; Kim, Ho Min
2017-01-01
The leukocyte common antigen-related receptor protein tyrosine phosphatases (LAR-RPTPs) are cellular receptors of heparan sulfate (HS) and chondroitin sulfate (CS) proteoglycans that direct axonal growth and neuronal regeneration. LAR-RPTPs are also synaptic adhesion molecules that form trans-synaptic adhesion complexes by binding to various postsynaptic adhesion ligands, such as Slit- and Trk-like family of proteins (Slitrks), IL-1 receptor accessory protein-like 1 (IL1RAPL1), interleukin-1 receptor accessory protein (IL-1RAcP) and neurotrophin receptor tyrosine kinase C (TrkC), to regulate synaptogenesis. Here, we determined the crystal structure of the human LAR-RPTP/IL1RAPL1 complex and found that lateral interactions between neighboring LAR-RPTP/IL1RAPL1 complexes in crystal lattices are critical for the higher-order assembly and synaptogenic activity of these complexes. Moreover, we found that LAR-RPTP binding to the postsynaptic adhesion ligands, Slitrk3, IL1RAPL1 and IL-1RAcP, but not TrkC, induces reciprocal higher-order clustering of trans-synaptic adhesion complexes. Although LAR-RPTP clustering was induced by either HS or postsynaptic adhesion ligands, the dominant binding of HS to the LAR-RPTP was capable of dismantling pre-established LAR-RPTP-mediated trans-synaptic adhesion complexes. These findings collectively suggest that LAR-RPTP clustering for synaptogenesis is modulated by a complex synapse-organizing protein network. PMID:29081732
Acute UV irradiation increases heparan sulfate proteoglycan levels in human skin.
Jung, Ji-Yong; Oh, Jang-Hee; Kim, Yeon Kyung; Shin, Mi Hee; Lee, Dayae; Chung, Jin Ho
2012-03-01
Glycosaminoglycans are important structural components in the skin and exist as various proteoglycan forms, except hyaluronic acid. Heparan sulfate (HS), one of the glycosaminoglycans, is composed of repeated disaccharide units, which are glucuronic acids linked to an N-acetyl-glucosamine or its sulfated forms. To investigate acute ultraviolet (UV)-induced changes of HS and HS proteoglycans (HSPGs), changes in levels of HS and several HSPGs in male human buttock skin were examined by immunohistochemistry and real-time quantitative polymerase chain reaction (qPCR) after 2 minimal erythema doses (MED) of UV irradiation (each n = 4-7). HS staining revealed that 2 MED of UV irradiation increased its expression, and staining for perlecan, syndecan-1, syndecan-4, CD44v3, and CD44 showed that UV irradiation increased their protein levels. However, analysis by real-time qPCR showed that UV irradiation did not change mRNA levels of CD44 and agrin, and decreased perlecan and syndecan-4 mRNA levels, while increased syndecan-1 mRNA level. As HS-synthesizing or -degrading enzymes, exostosin-1 and heparanase mRNA levels were increased, but exostosin-2 was decreased by UV irradiation. UV-induced matrix metalloproteinase-1 expression was confirmed for proper experimental conditions. Acute UV irradiation increases HS and HSPG levels in human skin, but their increase may not be mediated through their transcriptional regulation.
Glycosaminoglycan Distribution in the Rat Uterine Cervix During the Estrous Cycle
Cubas, Jairo Jose Matozinho; Simões, Ricardo Santos; Oliveira-Filho, Ricardo Martins; Simões, Manuel Jesus; Baracat, Edmund C; Soares, José Maria
2010-01-01
OBJECTIVE: To analyze the amount of glycosaminoglycans in the uterine cervix during each phase of the rat estrous cycle. DESIGN: Based on vaginal smears, forty female, regularly cycling rats were divided into four groups (n = 10 for each group): GI – proestrous, GII – estrous, GIII – metaestrous and GIV – diestrous. Animals were sacrificed at each phase of the cycle, and the cervix was immediately removed and submitted to biochemical extraction and determination of sulfated glycosaminoglycans and hyaluronic acid. The results were analyzed by ANOVA followed by the Bonferroni post-hoc test. RESULTS: The uterine cervix had the highest amount of total sulfated glycosaminoglycans and dermatan sulfate during the estrous phase (8.90 ± 0.55 mg/g of cetonic extract, p<0.001; and 8.86 ± 0.57 mg/g of cetonic extract, p<0.001). In addition, there was more heparan sulfate at the cervix during the proestrous phase (0.185 ± 0.03 mg/g of cetonic extract) than during any other phase (p<0.001). There were no significant changes in the concentration of hyaluronic acid in the uterine cervix during the estrous cycle. CONCLUSION: Our data suggest that the amount of total sulfated glycosaminoglycans may be influenced by hormonal fluctuations related to the estrous cycle, with dermatan sulfate and heparan sulfate being the glycosaminoglycans most sensitive to hormonal change. PMID:20668628
Salvestrini, Camilla; Lucas, Mark; Lionetti, Paolo; Torrente, Franco; James, Sean; Phillips, Alan D; Murch, Simon H
2014-01-01
We studied the expression of sulphated glycosaminoglycans (GAGs) in coeliac disease (CD) mucosa, as they are critical determinants of tissue volume, which increases in active disease. We also examined mucosal expression of IL-6, which stimulates excess GAG synthesis in disorders such as Grave's ophthalmopathy. We stained archival jejunal biopsies from 5 children with CD at diagnosis, on gluten-free diet and challenge for sulphated GAGs. We then examined duodenal biopsies from 9 children with CD compared to 9 histological normal controls, staining for sulphated GAGs, heparan sulphate proteoglycans (HSPG), short-chain HSPG (Δ-HSPG) and the proteoglycan syndecan-1 (CD138), which is expressed on epithelium and plasma cells. We confirmed findings with a second monoclonal in another 12 coeliac children. We determined mucosal IL-6 expression by immunohistochemistry and PCR in 9 further cases and controls, and used quantitative real time PCR for other Th17 pathway cytokines in an additional 10 cases and controls. In CD, HSPG expression was lost in the epithelial compartment but contrastingly maintained within an expanded lamina propria. Within the upper lamina propria, clusters of syndecan-1(+) plasma cells formed extensive syncytial sheets, comprising adherent plasma cells, lysed cells with punctate cytoplasmic staining and shed syndecan ectodomains. A dense infiltrate of IL-6(+) mononuclear cells was detected in active coeliac disease, also localised to the upper lamina propria, with significantly increased mRNA expression of IL-6 and IL-17A but not IL-23 p19. Matrix expansion, through syndecan-1(+) cell recruitment and lamina propria GAG increase, underpins villous atrophy in coeliac disease. The syndecan-1(+) cell syncytia and excess GAG production recapitulate elements of the invertebrate encapsulation reaction, itself dependent on insect transglutaminase and glutaminated early response proteins. As in other matrix expansion disorders, IL-6 is upregulated and represents a logical target for immunotherapy in patients with coeliac disease refractory to gluten-free diet.
Salvestrini, Camilla; Lucas, Mark; Lionetti, Paolo; Torrente, Franco; James, Sean; Phillips, Alan D.; Murch, Simon H.
2014-01-01
Background We studied the expression of sulphated glycosaminoglycans (GAGs) in coeliac disease (CD) mucosa, as they are critical determinants of tissue volume, which increases in active disease. We also examined mucosal expression of IL-6, which stimulates excess GAG synthesis in disorders such as Grave's ophthalmopathy. Methods We stained archival jejunal biopsies from 5 children with CD at diagnosis, on gluten-free diet and challenge for sulphated GAGs. We then examined duodenal biopsies from 9 children with CD compared to 9 histological normal controls, staining for sulphated GAGs, heparan sulphate proteoglycans (HSPG), short-chain HSPG (Δ-HSPG) and the proteoglycan syndecan-1 (CD138), which is expressed on epithelium and plasma cells. We confirmed findings with a second monoclonal in another 12 coeliac children. We determined mucosal IL-6 expression by immunohistochemistry and PCR in 9 further cases and controls, and used quantitative real time PCR for other Th17 pathway cytokines in an additional 10 cases and controls. Results In CD, HSPG expression was lost in the epithelial compartment but contrastingly maintained within an expanded lamina propria. Within the upper lamina propria, clusters of syndecan-1+ plasma cells formed extensive syncytial sheets, comprising adherent plasma cells, lysed cells with punctate cytoplasmic staining and shed syndecan ectodomains. A dense infiltrate of IL-6+ mononuclear cells was detected in active coeliac disease, also localised to the upper lamina propria, with significantly increased mRNA expression of IL-6 and IL-17A but not IL-23 p19. Conclusions Matrix expansion, through syndecan-1+ cell recruitment and lamina propria GAG increase, underpins villous atrophy in coeliac disease. The syndecan-1+ cell syncytia and excess GAG production recapitulate elements of the invertebrate encapsulation reaction, itself dependent on insect transglutaminase and glutaminated early response proteins. As in other matrix expansion disorders, IL-6 is upregulated and represents a logical target for immunotherapy in patients with coeliac disease refractory to gluten-free diet. PMID:25198673
Shabani, Samaneh H; Zakeri, Sedigheh; Salmanian, Ali H; Amani, Jafar; Mehrizi, Akram A; Snounou, Georges; Nosten, François; Andolina, Chiara; Mourtazavi, Yousef; Djadid, Navid D
2017-10-01
The circumsporozoite protein (CSP) of the malaria parasite Plasmodium vivax is a major pre-erythrocyte vaccine candidate. The protein has a central repeat region that belongs to one of repeat families (VK210, VK247, and the P. vivax-like). In the present study, computer modelling was employed to select chimeric proteins, comprising the conserved regions and different arrangements of the repeat elements (VK210 and VK247), whose structure is similar to that of the native counterparts. DNA encoding the selected chimeras (named CS127 and CS712) were synthetically constructed based on E. coli codons, then cloned and expressed. Mouse monoclonal antibodies (mAbs; anti-Pv-210-CDC and -Pv-247-CDC), recognized the chimeric antigens in ELISA, indicating correct conformation and accessibility of the B-cell epitopes. ELISA using IgG from plasma samples collected from 221 Iranian patients with acute P. vivax showed that only 49.32% of the samples reacted to both CS127 and CS712 proteins. The dominant subclass for the two chimeras was IgG1 (48% of the positive responders, OD 492 =0.777±0.420 for CS127; 48.41% of the positive responders, OD 492 =0.862±0.423 for CS712, with no statistically significant difference P>0.05; Wilcoxon signed ranks test). Binding assays showed that both chimeric proteins bound to immobilized heparan sulphate and HepG2 hepatocyte cells in a concentration-dependent manner, saturable at 80μg/mL. Additionally, anti-CS127 and -CS712 antibodies raised in mice recognized the native protein on the surface of P. vivax sporozoite with high intensity, confirming the presence of common epitopes between the recombinant forms and the native proteins. In summary, despite structural differences at the molecular level, the expression levels of both chimeras were satisfactory, and their conformational structure retained biological function, thus supporting their potential for use in the development of vivax-based vaccine. Copyright © 2017 Elsevier Ltd. All rights reserved.
The Role(s) of Heparan Sulfate Proteoglycan(s) in the wnt-1 Signaling Pathway
1998-08-01
First , the sequence of the cDNA, when compared to the genomic site of insertion of the P-element, revealed that the P-element is inserted 686 bp...stages 8 to 13 (Yoffe et al. 1995). We first examined whether ectopic expression of Wgts effectively restores the naked cuticle as it does in wg and...by Kjell~n and Lindahl, 1991) . HS/heparin N-deacetylase/N-sulfotransferase catalyzes N-deacetylation and N-sulfation that is the first and key step
Inoue, S; Osmond, D G
2001-11-01
Venous sinusoids in bone marrow are the site of a large-scale traffic of cells between the extravascular hemopoietic compartment and the blood stream. The wall of the sinusoids consists solely of a basement membrane interposed between a layer of endothelial cells and an incomplete covering of adventitial cells. To examine its possible structural specialization, the basement membrane of bone marrow sinusoids has now been examined by high resolution electron microscopy of perfusion-fixed mouse bone marrow. The basement membrane layer was discontinuous, consisting of irregular masses of amorphous material within a uniform 60-nm-wide space between apposing endothelial cells and adventitial cell processes. At maximal magnifications, the material was resolved as a random arrangement of components lacking the "cord network" formation seen in basement membranes elsewhere. Individual components exhibited distinctive ultrastructural features whose molecular identity has previously been established. By these morphological criteria, the basement membrane contained unusually abundant chondroitin sulfate proteoglycan (CSPG) revealed by 3-nm-wide "double tracks," and moderate amounts of both laminin as dense irregular coils and type IV collagen as 1-1.5-nm-wide filaments, together with less conspicuous amounts of amyloid P forming pentagonal frames. In contrast, 4.5-5-nm-wide "double tracks" characteristic of heparan sulfate proteoglycan (HSPG) were absent. The findings demonstrate that, in comparison with "typical" basement membranes in other tissues, the bone marrow sinusoidal basement membrane is uniquely specialized in several respects. Its discontinuous nature, lack of network organization, and absence of HSPG, a molecule that normally helps to maintain membrane integrity, may facilitate disassembly and reassembly of basement membrane material in concert with movements of adventitial cell processes as maturing hemopoietic cells pass through the sinusoidal wall: the exceptionally large quantity of CSPG may represent a reservoir of CD44 receptor for use in hemopoiesis. Copyright 2001 Wiley-Liss, Inc.
Wang, Raymond Y; Aminian, Afshin; McEntee, Michael F; Kan, Shih-Hsin; Simonaro, Calogera M; Lamanna, William C; Lawrence, Roger; Ellinwood, N Matthew; Guerra, Catalina; Le, Steven Q; Dickson, Patricia I; Esko, Jeffrey D
2014-08-01
Treatment with intravenous enzyme replacement therapy and hematopoietic stem cell transplantation for mucopolysaccharidosis (MPS) type I does not address joint disease, resulting in persistent orthopedic complications and impaired quality of life. A proof-of-concept study was conducted to determine the safety, tolerability, and efficacy of intra-articular recombinant human iduronidase (IA-rhIDUA) enzyme replacement therapy in the canine MPS I model. Four MPS I dogs underwent monthly rhIDUA injections (0.58 mg/joint) into the right elbow and knee for 6 months. Contralateral elbows and knees concurrently received normal saline. No intravenous rhIDUA therapy was administered. Monthly blood counts, chemistries, anti-rhIDUA antibody titers, and synovial fluid cell counts were measured. Lysosomal storage of synoviocytes and chondrocytes, synovial macrophages and plasma cells were scored at baseline and 1 month following the final injection. All injections were well-tolerated without adverse reactions. One animal required prednisone for spinal cord compression. There were no clinically significant abnormalities in blood counts or chemistries. Circulating anti-rhIDUA antibody titers gradually increased in all dogs except the prednisone-treated dog; plasma cells, which were absent in all baseline synovial specimens, were predominantly found in synovium of rhIDUA-treated joints at study-end. Lysosomal storage in synoviocytes and chondrocytes following 6 months of IA-rhIDUA demonstrated significant reduction compared to tissues at baseline, and saline-treated tissues at study-end. Mean joint synovial GAG levels in IA-rhIDUA joints were 8.62 ± 5.86 μg/mg dry weight and 21.6 ± 10.4 μg/mg dry weight in control joints (60% reduction). Cartilage heparan sulfate was also reduced in the IA-rhIDUA joints (113 ± 39.5 ng/g wet weight) compared to saline-treated joints (142 ± 56.4 ng/g wet weight). Synovial macrophage infiltration, which was present in all joints at baseline, was abolished in rhIDUA-treated joints only. Intra-articular rhIDUA is well-tolerated and safe in the canine MPS I animal model. Qualitative and quantitative assessments indicate that IA-rhIDUA successfully reduces tissue and cellular GAG storage in synovium and articular cartilage, including cartilage deep to the articular surface, and eliminates inflammatory macrophages from synovial tissue. The MPS I canine IA-rhIDUA results suggest that clinical studies should be performed to determine if IA-rhIDUA is a viable approach to ameliorating refractory orthopedic disease in human MPS I. Copyright © 2014 Elsevier Inc. All rights reserved.
Ivanov, Vadim; Ivanova, Svetlana; Kalinovsky, Tatiana; Niedzwiecki, Aleksandra; Rath, Matthias
2008-07-01
Monocyte adhesion to endothelium plays an important role in atherosclerosis. We investigated the effects of micronutrients on monocyte-binding properties of extracellular matrix (ECM) produced by human aortic endothelial cells (AoEC). Confluent cultures of AoEC were exposed to ascorbic acid, quercetin, gotu kola extract (10% asiatic acid), green tea extract (40% epigallocatechin gallate), or a mixture of these micronutrients for 48 hours. AoEC-produced ECM was exposed by differential treatment. U937 monocyte adhesion was assayed by fluorescence. ECM composition was assayed immunochemically and with radiolabeled metabolic precursors. AoEC exposure to micronutrients reduced ECM capacity to bind monocytes in a dose-dependent manner. This effect was accompanied by profound changes in the ECM composition. Correlation analysis revealed that changes in monocyte adhesion to ECM had the strongest positive correlation with ECM content for laminin (CC = 0.9681, P < 0.01), followed by fibronectin, collagens type III, I, and IV, biglycan, heparan sulfate, and elastin. The strongest negative correlation was with chondroitin sulfate (CC = -0.9623, P < 0.01), followed by perlecan and versican. Individual micronutrients had diverse effects on ECM composition and binding properties, and their mixture was the most effective treatment. In conclusion, micronutrient-dependent reduction of monocyte adhesion to endothelium is partly mediated through specific modulation of ECM composition and properties.
Fan, Yi-Chin; Chen, Jo-Mei; Lin, Jen-Wei; Chen, Yi-Ying; Wu, Guan-Hong; Su, Kuan-Hsuan; Chiou, Ming-Tang; Wu, Shang-Rung; Yin, Ji-Hang; Liao, Jiunn-Wang; Chang, Gwong-Jen J; Chiou, Shyan-Song
2018-05-10
Swine are a critical amplifying host involved in human Japanese encephalitis (JE) outbreaks. Cross-genotypic immunogenicity and sterile protection are important for the current genotype III (GIII) virus-derived vaccines in swine, especially now that emerging genotype I (GI) JE virus (JEV) has replaced GIII virus as the dominant strain. Herein, we aimed to develop a system to generate GI JEV virus-like particles (VLPs) and evaluate the immunogenicity and protection of the GI vaccine candidate in mice and specific pathogen-free swine. A CHO-heparan sulfate-deficient (CHO-HS(-)) cell clone, named 51-10 clone, stably expressing GI-JEV VLP was selected and continually secreted GI VLPs without signs of cell fusion. 51-10 VLPs formed a homogeneously empty-particle morphology and exhibited similar antigenic activity as GI virus. GI VLP-immunized mice showed balanced cross-neutralizing antibody titers against GI to GIV viruses (50% focus-reduction micro-neutralization assay titers 71 to 240) as well as potent protection against GI or GIII virus infection. GI VLP-immunized swine challenged with GI or GIII viruses showed no fever, viremia, or viral RNA in tonsils, lymph nodes, and brains as compared with phosphate buffered saline-immunized swine. We thus conclude GI VLPs can provide sterile protection against GI and GIII viruses in swine.
Roca, Carles; Motas, Sandra; Marcó, Sara; Ribera, Albert; Sánchez, Víctor; Sánchez, Xavier; Bertolin, Joan; León, Xavier; Pérez, Jennifer; Garcia, Miguel; Villacampa, Pilar; Ruberte, Jesús; Pujol, Anna; Haurigot, Virginia; Bosch, Fatima
2017-04-15
Gene therapy is a promising therapeutic alternative for Lysosomal Storage Disorders (LSD), as it is not necessary to correct the genetic defect in all cells of an organ to achieve therapeutically significant levels of enzyme in body fluids, from which non-transduced cells can uptake the protein correcting their enzymatic deficiency. Animal models are instrumental in the development of new treatments for LSD. Here we report the generation of the first mouse model of the LSD Muccopolysaccharidosis Type IIID (MPSIIID), also known as Sanfilippo syndrome type D. This autosomic recessive, heparan sulphate storage disease is caused by deficiency in N-acetylglucosamine 6-sulfatase (GNS). Mice deficient in GNS showed lysosomal storage pathology and loss of lysosomal homeostasis in the CNS and peripheral tissues, chronic widespread neuroinflammation, reduced locomotor and exploratory activity and shortened lifespan, a phenotype that closely resembled human MPSIIID. Moreover, treatment of the GNS-deficient animals with GNS-encoding adeno-associated viral (AAV) vectors of serotype 9 delivered to the cerebrospinal fluid completely corrected pathological storage, improved lysosomal functionality in the CNS and somatic tissues, resolved neuroinflammation, restored normal behaviour and extended lifespan of treated mice. Hence, this work represents the first step towards the development of a treatment for MPSIIID. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Heparanase and Syndecan-4 Are Involved in Low Molecular Weight Fucoidan-Induced Angiogenesis
Haddad, Oualid; Guyot, Erwan; Marinval, Nicolas; Chevalier, Fabien; Maillard, Loïc; Gadi, Latifa; Laguillier-Morizot, Christelle; Oudar, Olivier; Sutton, Angela; Charnaux, Nathalie; Hlawaty, Hanna
2015-01-01
Induction of angiogenesis is a potential treatment for chronic ischemia. Low molecular weight fucoidan (LMWF), the sulfated polysaccharide from brown seaweeds, has been shown to promote revascularization in a rat limb ischemia, increasing angiogenesis in vivo. We investigated the potential role of two heparan sulfate (HS) metabolism enzymes, exostosin-2 (EXT2) and heparanase (HPSE), and of two HS-membrane proteoglycans, syndecan-1 and -4 (SDC-1 and SDC-4), in LMWF induced angiogenesis. Our results showed that LMWF increases human vascular endothelial cell (HUVEC) migration and angiogenesis in vitro. We report that the expression and activity of the HS-degrading HPSE was increased after LMWF treatment. The phenotypic tests of LMWF-treated and EXT2- or HPSE-siRNA-transfected cells indicated that EXT2 or HPSE expression significantly affect the proangiogenic potential of LMWF. In addition, LMWF increased SDC-1, but decreased SDC-4 expressions. The effect of LMWF depends on SDC-4 expression. Silencing EXT2 or HPSE leads to an increased expression of SDC-4, providing the evidence that EXT2 and HPSE regulate the SDC-4 expression. Altogether, these data indicate that EXT2, HPSE, and SDC-4 are involved in the proangiogenic effects of LMWF, suggesting that the HS metabolism changes linked to LMWF-induced angiogenesis offer the opportunity for new therapeutic strategies of ischemic diseases. PMID:26516869
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stiegler,A.; Burden, S.; Hubbard, S.
Muscle-specific kinase (MuSK) is a receptor tyrosine kinase expressed exclusively in skeletal muscle, where it is required for formation of the neuromuscular junction. MuSK is activated by agrin, a neuron-derived heparan sulfate proteoglycan. Here, we report the crystal structure of the agrin-responsive first and second immunoglobulin-like domains (Ig1 and Ig2) of the MuSK ectodomain at 2.2 {angstrom} resolution. The structure reveals that MuSK Ig1 and Ig2 are Ig-like domains of the I-set subfamily, which are configured in a linear, semi-rigid arrangement. In addition to the canonical internal disulfide bridge, Ig1 contains a second, solvent-exposed disulfide bridge, which our biochemical datamore » indicate is critical for proper folding of Ig1 and processing of MuSK. Two Ig1-2 molecules form a non-crystallographic dimer that is mediated by a unique hydrophobic patch on the surface of Ig1. Biochemical analyses of MuSK mutants introduced into MuSK{sup -/-} myotubes demonstrate that residues in this hydrophobic patch are critical for agrin-induced MuSK activation.« less
Sulfatase-mediated manipulation of the astrocyte-Schwann cell interface.
O'Neill, Paul; Lindsay, Susan L; Pantiru, Andreea; Guimond, Scott E; Fagoe, Nitish; Verhaagen, Joost; Turnbull, Jeremy E; Riddell, John S; Barnett, Susan C
2017-01-01
Schwann cell (SC) transplantation following spinal cord injury (SCI) may have therapeutic potential. Functional recovery is limited however, due to poor SC interactions with host astrocytes and the induction of astrogliosis. Olfactory ensheathing cells (OECs) are closely related to SCs, but intermix more readily with astrocytes in culture and induce less astrogliosis. We previously demonstrated that OECs express higher levels of sulfatases, enzymes that remove 6-O-sulfate groups from heparan sulphate proteoglycans, than SCs and that RNAi knockdown of sulfatase prevented OEC-astrocyte mixing in vitro. As human OECs are difficult to culture in large numbers we have genetically engineered SCs using lentiviral vectors to express sulfatase 1 and 2 (SC-S1S2) and assessed their ability to interact with astrocytes. We demonstrate that SC-S1S2s have increased integrin-dependent motility in the presence of astrocytes via modulation of NRG and FGF receptor-linked PI3K/AKT intracellular signaling and do not form boundaries with astrocytes in culture. SC-astrocyte mixing is dependent on local NRG concentration and we propose that sulfatase enzymes influence the bioavailability of NRG ligand and thus influence SC behavior. We further demonstrate that injection of sulfatase expressing SCs into spinal cord white matter results in less glial reactivity than control SC injections comparable to that of OEC injections. Our data indicate that sulfatase-mediated modification of the extracellular matrix can influence glial interactions with astrocytes, and that SCs engineered to express sulfatase may be more OEC-like in character. This approach may be beneficial for cell transplant-mediated spinal cord repair. GLIA 2016 GLIA 2017;65:19-33. © 2016 The Authors. Glia Published by Wiley Periodicals, Inc.
Addad, Sourour; Exposito, Jean-Yves; Faye, Clément; Ricard-Blum, Sylvie; Lethias, Claire
2011-01-01
Fibrillar collagens are the more abundant extracellular proteins. They form a metazoan-specific family, and are highly conserved from sponge to human. Their structural and physiological properties have been successfully used in the food, cosmetic, and pharmaceutical industries. On the other hand, the increase of jellyfish has led us to consider this marine animal as a natural product for food and medicine. Here, we have tested different Mediterranean jellyfish species in order to investigate the economic potential of their collagens. We have studied different methods of collagen purification (tissues and experimental procedures). The best collagen yield was obtained using Rhizostoma pulmo oral arms and the pepsin extraction method (2–10 mg collagen/g of wet tissue). Although a significant yield was obtained with Cotylorhiza tuberculata (0.45 mg/g), R. pulmo was used for further experiments, this jellyfish being considered as harmless to humans and being an abundant source of material. Then, we compared the biological properties of R. pulmo collagen with mammalian fibrillar collagens in cell cytotoxicity assays and cell adhesion. There was no statistical difference in cytotoxicity (p > 0.05) between R. pulmo collagen and rat type I collagen. However, since heparin inhibits cell adhesion to jellyfish-native collagen by 55%, the main difference is that heparan sulfate proteoglycans could be preferentially involved in fibroblast and osteoblast adhesion to jellyfish collagens. Our data confirm the broad harmlessness of jellyfish collagens, and their biological effect on human cells that are similar to that of mammalian type I collagen. Given the bioavailability of jellyfish collagen and its biological properties, this marine material is thus a good candidate for replacing bovine or human collagens in selected biomedical applications. PMID:21747742
Addad, Sourour; Exposito, Jean-Yves; Faye, Clément; Ricard-Blum, Sylvie; Lethias, Claire
2011-01-01
Fibrillar collagens are the more abundant extracellular proteins. They form a metazoan-specific family, and are highly conserved from sponge to human. Their structural and physiological properties have been successfully used in the food, cosmetic, and pharmaceutical industries. On the other hand, the increase of jellyfish has led us to consider this marine animal as a natural product for food and medicine. Here, we have tested different Mediterranean jellyfish species in order to investigate the economic potential of their collagens. We have studied different methods of collagen purification (tissues and experimental procedures). The best collagen yield was obtained using Rhizostoma pulmo oral arms and the pepsin extraction method (2-10 mg collagen/g of wet tissue). Although a significant yield was obtained with Cotylorhiza tuberculata (0.45 mg/g), R. pulmo was used for further experiments, this jellyfish being considered as harmless to humans and being an abundant source of material. Then, we compared the biological properties of R. pulmo collagen with mammalian fibrillar collagens in cell cytotoxicity assays and cell adhesion. There was no statistical difference in cytotoxicity (p > 0.05) between R. pulmo collagen and rat type I collagen. However, since heparin inhibits cell adhesion to jellyfish-native collagen by 55%, the main difference is that heparan sulfate proteoglycans could be preferentially involved in fibroblast and osteoblast adhesion to jellyfish collagens. Our data confirm the broad harmlessness of jellyfish collagens, and their biological effect on human cells that are similar to that of mammalian type I collagen. Given the bioavailability of jellyfish collagen and its biological properties, this marine material is thus a good candidate for replacing bovine or human collagens in selected biomedical applications.
How members of the human gut microbiota overcome the sulfation problem posed by glycosaminoglycans.
Cartmell, Alan; Lowe, Elisabeth C; Baslé, Arnaud; Firbank, Susan J; Ndeh, Didier A; Murray, Heath; Terrapon, Nicolas; Lombard, Vincent; Henrissat, Bernard; Turnbull, Jeremy E; Czjzek, Mirjam; Gilbert, Harry J; Bolam, David N
2017-07-03
The human microbiota, which plays an important role in health and disease, uses complex carbohydrates as a major source of nutrients. Utilization hierarchy indicates that the host glycosaminoglycans heparin (Hep) and heparan sulfate (HS) are high-priority carbohydrates for Bacteroides thetaiotaomicron , a prominent member of the human microbiota. The sulfation patterns of these glycosaminoglycans are highly variable, which presents a significant enzymatic challenge to the polysaccharide lyases and sulfatases that mediate degradation. It is possible that the bacterium recruits lyases with highly plastic specificities and expresses a repertoire of enzymes that target substructures of the glycosaminoglycans with variable sulfation or that the glycans are desulfated before cleavage by the lyases. To distinguish between these mechanisms, the components of the B. thetaiotaomicron Hep/HS degrading apparatus were analyzed. The data showed that the bacterium expressed a single-surface endo-acting lyase that cleaved HS, reflecting its higher molecular weight compared with Hep. Both Hep and HS oligosaccharides imported into the periplasm were degraded by a repertoire of lyases, with each enzyme displaying specificity for substructures within these glycosaminoglycans that display a different degree of sulfation. Furthermore, the crystal structures of a key surface glycan binding protein, which is able to bind both Hep and HS, and periplasmic sulfatases reveal the major specificity determinants for these proteins. The locus described here is highly conserved within the human gut Bacteroides , indicating that the model developed is of generic relevance to this important microbial community.
Changes in glomerular parietal epithelial cells in mouse kidneys with advanced age
Roeder, Sebastian S.; Stefanska, Ania; Eng, Diana G.; Kaverina, Natalya; Sunseri, Maria W.; McNicholas, Bairbre A.; Rabinovitch, Peter; Engel, Felix B.; Daniel, Christoph; Amann, Kerstin; Lichtnekert, Julia; Pippin, Jeffrey W.
2015-01-01
Kidney aging is accompanied by characteristic changes in the glomerulus, but little is known about the effect of aging on glomerular parietal epithelial cells (PECs), nor if the characteristic glomerular changes in humans and rats also occur in very old mice. Accordingly, a descriptive analysis was undertaken in 27-mo-old C57B6 mice, considered advanced age. PEC density was significantly lower in older mice compared with young mice (aged 3 mo), and the decrease was more pronounced in juxtamedullary glomeruli compared with outer cortical glomeruli. In addition to segmental and global glomerulosclerosis in older mice, staining for matrix proteins collagen type IV and heparan sulfate proteoglycan were markedly increased in Bowman's capsules of older mouse glomeruli, consistent with increased extracellular matrix production by PECs. De novo staining for CD44, a marker of activated and profibrotic PECs, was significantly increased in aged glomeruli. CD44 staining was more pronounced in the juxtamedullary region and colocalized with phosphorylated ERK. Additionally, a subset of aged PECs de novo expressed the epithelial-to-mesenchymal transition markers α-smooth muscle and vimentin, with no changes in epithelial-to-mesenchymal transition markers E-cadherin and β-catenin. The mural cell markers neural/glial antigen 2, PDGF receptor-β, and CD146 as well as Notch 3 were also substantially increased in aged PECs. These data show that mice can be used to better understand the aging kidney and that PECs undergo substantial changes, especially in juxtamedullary glomeruli, that may participate in the overall decline in glomerular structure and function with advancing age. PMID:26017974
RB4CD12 epitope expression and heparan sulfate disaccharide composition in brain vasculature.
Hosono-Fukao, Tomomi; Ohtake-Niimi, Shiori; Nishitsuji, Kazuchika; Hossain, Md Motarab; van Kuppevelt, Toin H; Michikawa, Makoto; Uchimura, Kenji
2011-11-01
RB4CD12 is a phage display antibody that recognizes a heparan sulfate (HS) glycosaminoglycan epitope. The epitope structure is proposed to contain a trisulfated disaccharide, [-IdoA(2-OSO(3))-GlcNSO(3) (6-OSO(3))-], which supports HS binding to various macromolecules such as growth factors and cytokines in central nervous tissues. Chemically modified heparins that lack the trisulfated disaccharides failed to inhibit the RB4CD12 recognition of HS chains. To determine the localization of the RB4CD12 anti-HS epitope in the brain, we performed an immunohistochemical analysis for cryocut sections of mouse brain. The RB4CD12 staining signals were colocalized with laminin and were detected abundantly in the vascular basement membrane. Bacterial heparinases eliminated the RB4CD12 staining signals. The RB4CD12 epitope localization was confirmed by immunoelectron microscopy. Western blotting analysis revealed that the size of a major RB4CD12-positive molecule is ∼460 kDa in a vessel-enriched fraction of the mouse brain. Disaccharide analysis with reversed-phase ion-pair HPLC showed that [-IdoA(2-OSO(3))-GlcNSO(3) (6-OSO(3))-] trisulfated disaccharide residues are present in HS purified from the vessel-enriched brain fraction. These results indicated that the RB4CD12 anti-HS epitope exists in large quantities in the brain vascular basement membrane. Copyright © 2011 Wiley-Liss, Inc.
BTBR T+tf/J MICE: AUTISM-RELEVANT BEHAVIORS AND REDUCED FRACTONE-ASSOCIATED HEPARAN SULFATE
Blanchard, D. Caroline; Defensor, Erwin B.; Meyza, Ksenia Z.; Pobbe, Roger L.H.; Pearson, Brandon L.; Bolivar, Valerie J.; Blanchard, Robert J.
2011-01-01
BTBR T+tf/J (BTBR) mice have emerged as strong candidates to serve as models of a range of autism-relevant behaviors, showing deficiencies in social behaviors; reduced or unusual ultrasonic vocalizations in conspecific situations; and enhanced, repetitive self grooming. Recent studies have described their behaviors in a seminatural Visible Burrow System (VBS); a social proximity test in which avoidance of a conspecific is impossible; and in an object approach and investigation test evaluating attention to specific objects and potential stereotypies in the order of approaching/investigating objects. VBS results confirmed strong BTBR avoidance of conspecifics and in the social proximity test, BTBR showed dramatic differences in several close-in behaviors, including specific avoidance of a nose-to-nose contact that may potentially be related to gaze-avoidance. Diazepam normalized social avoidance by BTBRs in a three-chamber test, and some additional behaviors –but not nose to nose avoidance- in the social proximity test. BTBR also showed higher levels of preference for particular objects, and higher levels of sequences investigating 3- or 4- objects in the same order. Heparan sulfate (HS) associated with fractal structures in the subventricular zone of the lateral ventricles was severely reduced in BTBR. HS may modulate the functions of a range of growth and guidance factors during development, and HS abnormalities are associated with relevant brain (callosal agenesis) and behavioral (reductions in sociality) changes; suggesting the value of examination of the dynamics of the HS system in the context of autism. PMID:21741402
1986-01-01
It is generally proposed that embryonic mesenchymal cells use sulfated macromolecules during in situ migration. Attempts to resolve the molecular mechanisms for this hypothesis using planar substrates have been met with limited success. In the present study, we provide evidence that the functional significance of certain sulfated macromolecules during mesenchyme migration required the presence of the endogenous migratory template; i.e., native collagen fibrils. Using three-dimensional collagen gel lattices and whole embryo culture procedures to produce metabolically labeled sulfated macromolecules in embryonic chick cardiac tissue, we show that these molecules were primarily proteoglycan (PG) in nature and that their distribution was class specific; i.e., heparan sulfate PG, the minor labeled component (15%), remained pericellular while chondroitin sulfate (CS) PG, the predominately labeled PG (85%), was associated with collagen fibrils as "trails" of 50-60-nm particles when viewed by scanning electron microscopy. Progressive "conditioning" of collagen with CS-PG inhibited the capacity of the template to support subsequent cell migration. Lastly, metabolically labeled, PG-derived CS chains were compared with respect to degree of sulfation in either the C-6 or C-4 position by chromatographic separation of chondroitinase AC digestion products. Results from temporal and regional comparisons of in situ-labeled PGs indicated a positive correlation between the presence of mesenchyme and an enrichment of disaccharide-4S relative to that from regions lacking mesenchyme (i.e., principally myocardial tissue). The suggestion of a mesenchyme-specific CS-PG was substantiated by similarly examining the PGs synthesized solely by cardiac mesenchymal cells migrating within hydrated collagen lattice in culture. These data were incorporated into a model of "substratum conditioning" which provides a molecular mechanism by which secretion of mesenchyme-specific CS-PGs not only provides for directed and sustained cell movement, but ultimately inhibits migration of the cell population as a whole. PMID:3782305
Adeno-associated virus-2 and its primary cellular receptor-Cryo-EM structure of a heparin complex
DOE Office of Scientific and Technical Information (OSTI.GOV)
O'Donnell, Jason; Taylor, Kenneth A.; Chapman, Michael S.
2009-03-15
Adeno-associated virus serotype 2 (AAV-2) is a leading candidate vector for gene therapy. Cell entry starts with attachment to a primary receptor, Heparan Sulfate Proteoglycan (HSPG) before binding to a co-receptor. Here, cryo-electron microscopy provides direct visualization of the virus-HSPG interactions. Single particle analysis was performed on AAV-2 complexed with a 17 kDa heparin fragment at 8.3 A resolution. Heparin density covers the shoulder of spikes surrounding viral 3-fold symmetry axes. Previously implicated, positively charged residues R{sub 448/585}, R{sub 451/588} and R{sub 350/487} from another subunit cluster at the center of the heparin footprint. The footprint is much more extensivemore » than apparent through mutagenesis, including R{sub 347/484}, K{sub 395/532} and K{sub 390/527} that are more conserved, but whose roles have been controversial. It also includes much of a region proposed as a co-receptor site, because prior studies had not revealed heparin interactions. Heparin density bridges over the viral 3-fold axes, indicating multi-valent attachment to symmetry-related binding sites.« less
Broad-spectrum non-toxic antiviral nanoparticles with a virucidal inhibition mechanism
NASA Astrophysics Data System (ADS)
Cagno, Valeria; Andreozzi, Patrizia; D'Alicarnasso, Marco; Jacob Silva, Paulo; Mueller, Marie; Galloux, Marie; Le Goffic, Ronan; Jones, Samuel T.; Vallino, Marta; Hodek, Jan; Weber, Jan; Sen, Soumyo; Janeček, Emma-Rose; Bekdemir, Ahmet; Sanavio, Barbara; Martinelli, Chiara; Donalisio, Manuela; Rameix Welti, Marie-Anne; Eleouet, Jean-Francois; Han, Yanxiao; Kaiser, Laurent; Vukovic, Lela; Tapparel, Caroline; Král, Petr; Krol, Silke; Lembo, David; Stellacci, Francesco
2018-02-01
Viral infections kill millions yearly. Available antiviral drugs are virus-specific and active against a limited panel of human pathogens. There are broad-spectrum substances that prevent the first step of virus-cell interaction by mimicking heparan sulfate proteoglycans (HSPG), the highly conserved target of viral attachment ligands (VALs). The reversible binding mechanism prevents their use as a drug, because, upon dilution, the inhibition is lost. Known VALs are made of closely packed repeating units, but the aforementioned substances are able to bind only a few of them. We designed antiviral nanoparticles with long and flexible linkers mimicking HSPG, allowing for effective viral association with a binding that we simulate to be strong and multivalent to the VAL repeating units, generating forces (~190 pN) that eventually lead to irreversible viral deformation. Virucidal assays, electron microscopy images, and molecular dynamics simulations support the proposed mechanism. These particles show no cytotoxicity, and in vitro nanomolar irreversible activity against herpes simplex virus (HSV), human papilloma virus, respiratory syncytial virus (RSV), dengue and lenti virus. They are active ex vivo in human cervicovaginal histocultures infected by HSV-2 and in vivo in mice infected with RSV.
The vascular basement membrane in the healthy and pathological brain.
Thomsen, Maj S; Routhe, Lisa J; Moos, Torben
2017-10-01
The vascular basement membrane contributes to the integrity of the blood-brain barrier (BBB), which is formed by brain capillary endothelial cells (BCECs). The BCECs receive support from pericytes embedded in the vascular basement membrane and from astrocyte endfeet. The vascular basement membrane forms a three-dimensional protein network predominantly composed of laminin, collagen IV, nidogen, and heparan sulfate proteoglycans that mutually support interactions between BCECs, pericytes, and astrocytes. Major changes in the molecular composition of the vascular basement membrane are observed in acute and chronic neuropathological settings. In the present review, we cover the significance of the vascular basement membrane in the healthy and pathological brain. In stroke, loss of BBB integrity is accompanied by upregulation of proteolytic enzymes and degradation of vascular basement membrane proteins. There is yet no causal relationship between expression or activity of matrix proteases and the degradation of vascular matrix proteins in vivo. In Alzheimer's disease, changes in the vascular basement membrane include accumulation of Aβ, composite changes, and thickening. The physical properties of the vascular basement membrane carry the potential of obstructing drug delivery to the brain, e.g. thickening of the basement membrane can affect drug delivery to the brain, especially the delivery of nanoparticles.
Fibroblast growth factors, old kids on the new block
Li, Xiaokun; Wang, Cong; Xiao, Jian; McKeehan, Wallace L.; Wang, Fen
2016-01-01
The fibroblast growth factors (FGFs) are a family of cell intrinsic regulatory peptides that control a broad spectrum of cellular activities. The family includes canonic FGFs that elicit their activities by activating the FGF receptor (FGFR) tyrosine kinase and non-canonic members that elicit their activities intracellularly and via FGFR-independent mechanisms. The FGF signaling axis is highly complex due to the existence of multiple isoforms of both ligands and receptors, as well as cofactors that include the chemically heterogeneous heparan sulfate (HS) cofactors, and in the case of endocrine FGFs, the Klotho coreceptors. Resident FGF signaling controls embryonic development, maintains tissue homeostasis, promotes wound healing and tissue regeneration, and regulates functions of multiple organs. However, ectopic or aberrant FGF signaling is a culprit for various diseases, including congenital birth defects, metabolic disorder, and cancer. The molecular mechanisms by which the specificity of FGF signaling is achieved remain incompletely understood. Since its application as a druggable target has been gradually recognized by pharmaceutical companies and translational researchers, understanding the determinants of FGF signaling specificity has become even more important in order to get into the position to selectively suppress a particular pathway without affecting others to minimize side effects. PMID:26768548
Regeneration and Maintenance of Intestinal Smooth Muscle Phenotypes
NASA Astrophysics Data System (ADS)
Walthers, Christopher M.
Tissue engineering is an emerging field of biomedical engineering that involves growing artificial organs to replace those lost to disease or injury. Within tissue engineering, there is a demand for artificial smooth muscle to repair tissues of the digestive tract, bladder, and vascular systems. Attempts to develop engineered smooth muscle tissues capable of contracting with sufficient strength to be clinically relevant have so far proven unsatisfactory. The goal of this research was to develop and sustain mature, contractile smooth muscle. Survival of implanted SMCs is critical to sustain the benefits of engineered smooth muscle. Survival of implanted smooth muscle cells was studied with layered, electrospun polycaprolactone implants with lasercut holes ranging from 0--25% porosity. It was found that greater angiogenesis was associated with increased survival of implanted cells, with a large increase at a threshold between 20% and 25% porosity. Heparan sulfate coatings improved the speed of blood vessel infiltration after 14 days of implantation. With these considerations, thicker engineered tissues may be possible. An improved smooth muscle tissue culture technique was utilized. Contracting smooth muscle was produced in culture by maintaining the native smooth muscle tissue organization, specifically by sustaining intact smooth muscle strips rather than dissociating tissue in to isolated smooth muscle cells. Isolated cells showed a decrease in maturity and contained fewer enteric neural and glial cells. Muscle strips also exhibited periodic contraction and regular fluctuation of intracellular calclium. The muscle strip maturity persisted after implantation in omentum for 14 days on polycaprolactone scaffolds. A low-cost, disposable bioreactor was developed to further improve maturity of cultured smooth muscle cells in an environment of controlled cyclical stress.The bioreactor consistently applied repeated mechanical strain with controllable inputs for strain, frequency, and duty cycle. Cells grown on protein-conjugated silicone membranes showed a morphological change while undergoing bioreactor stress. Analyzing change in muscle strips undergoing bioreactor stress is an area for future research. The overall goal of this research was to move engineered smooth muscle towards tissues capable of contracting with physiologically relevant strength and frequency. This approach first increased survival of smooth muscle constructs, and then sought to improve contractile ability of smooth muscle cells.
Moczar, M; Robert, A M; Jacotot, B; Robert, L
2001-05-01
The effect of an alpha-blocking agent and of a beta-blocking agent on the biosynthesis of extracellular matrix macromolecules of the arterial wall was investigated. Rabbit aorta explants were cultured up to 48 hours with radioactive proline, lysine or glucosamine. In presence of these drugs, at concentration shown to be effective for the inhibition of platelet-endothelial cell interactions (10(-7) M), the incorporation of 14C proline in total macromolecular proline was higher than in macromolecular hydroxyproline suggesting a relatively higher rate of biosynthesis of non-collagenous proteins as compared to collagens. The alpha-blocking increased the incorporation of 14C proline in collagenous and non-collagenous proteins after 18 hours of incubation. beta-blocking also increased the incorporation of proline in macromolecular proline and hydroxyproline as compared to control cultures. Both increased the incorporation of 3H glucosamine in newly synthesised glycosaminoglycans. beta-blocking increased mainly the neosynthesis of heparan sulphate, alpha-blocking that of hyaluronan. The incorporation of 14C-lysine in crosslinked, insoluble elastin was not modified. These experiments confirm that alpha and beta-blocking agents can influence not only the tonus of aortic smooth muscle cells but also the relative rates of biosynthesis of extracellular matrix macromolecules. This effect should be taken in consideration for the evaluation of the long range effect of alpha and beta-blocking drugs on the vascular wall.
Observational Prospective Natural History of Patients with Sanfilippo Syndrome Type B.
Whitley, Chester B; Cleary, Maureen; Eugen Mengel, Karl; Harmatz, Paul; Shapiro, Elsa; Nestrasil, Igor; Haslett, Patrick; Whiteman, David; Alexanderian, David
2018-06-01
To evaluate the natural course of disease progression in patients with Sanfilippo syndrome type B (mucopolysaccharidosis type IIIB), identify potential end points for future therapy trials, and characterize biomarkers related to the disease. A prospective, multicenter study was conducted. Baseline, 6-month, and 12-month assessments included neurodevelopmental status (Bayley Scales of Infant Development, Third edition), adaptive status (Vineland Adaptive Behavior Scales, Second Edition), volumetric brain magnetic resonance imaging, cerebrospinal fluid heparan sulfate, and urine glycosaminoglycan (GAG) measurements. Nineteen patients aged 1.6-31.7 years were enrolled. Over 12 months, cognition, adaptive behavior, and cortical gray matter volume (GMV) declined in most patients. For patients diagnosed at <6 years, although there was no overall mean change over 12 months, there were 10%-48%, 3%-66%, and 1%-14% decreases in cognitive development quotient score, Vineland Adaptive Behavior Scales, Second Edition development quotient score, and cortical GMV in 8/12, 9/11, and 10/11 patients, respectively. Mean urine GAG and cerebrospinal fluid heparan sulfate levels were stable, but patients diagnosed at <6 years (n = 14) had higher levels than those ≥6 years at diagnosis (n = 4), which was likely associated with age as they also were generally younger. Cognition, adaptive behavior, and cortical GMV measures sensitively tracked deterioration in patients with mucopolysaccharidosis type IIIB aged ≤8.6 years. Biomarkers may have prognostic value, but their sensitivity to disease progression requires further investigation. These findings should help evaluate enzyme replacement and gene therapy agents for this rare, devastating, neurodegenerative disease. ClinicalTrials.gov: NCT01509768. Copyright © 2018 Elsevier Inc. All rights reserved.
Fibrinogen, Riboflavin, and UVA to Immobilize a Corneal Flap – Molecular Mechanisms
Littlechild, Stacy L.; Zhang, Yuntao; Tomich, John M.; Conrad, Gary W.
2012-01-01
Purpose. Tissue glue containing fibrinogen (FIB) and riboflavin (RF), upon exposure to long wavelength ultraviolet light (UVA, 365 nM) has been proposed potentially to solve long-standing problems presented by corneal wound and epithelial ingrowth side-effects from laser-assisted in situ keratomileuis (LASIK). Data presented in a previous study demonstrated an ability of FIB + RF + UVA to adhere two stromal surfaces; however, to our knowledge no molecular mechanisms have been proposed to account for interactions occurring between corneal extracellular matrix (ECM) and tissue glue molecules. Here, we document several covalent and noncovalent interactions between these classes of macromolecules. Methods. SDS-PAGE and Western blot techniques were used to identify covalent interactions between tissue glue molecules and corneal ECM molecules in either the presence or absence of RF and UVA, in vitro and ex vivo. Surface plasmon resonance (SPR) was used to characterize noncovalent interactions, and obtain ka, kd, and KD binding affinity values. Results. SDS-PAGE and Western blot analyses indicated that covalent interactions occurred between neighboring FIB molecules, as well as between FIB and collagen type I (Coll-I) proteins (in vitro and ex vivo). These interactions occurred only in the presence of RF and UVA. SPR data demonstrated the ability of FIB to bind noncovalently to corneal stroma molecules, Coll-I, decorin, dermatan sulfate, and corneal basement membrane molecules, laminin and heparan sulfate – only in the presence of Zn2+. Conclusions. Covalent and (zinc-mediated) noncovalent mechanisms involving FIB and stromal ECM molecules contribute to the adhesion created by FIB + RF + UVA. PMID:22879413
Li, Zixuan; Moniz, Heather; Wang, Shuo; Ramiah, Annapoorani; Zhang, Fuming; Moremen, Kelley W.; Linhardt, Robert J.; Sharp, Joshua S.
2015-01-01
Interaction of transmembrane receptors of the Robo family and the secreted protein Slit provides important signals in the development of the central nervous system and regulation of axonal midline crossing. Heparan sulfate, a sulfated linear polysaccharide modified in a complex variety of ways, serves as an essential co-receptor in Slit-Robo signaling. Previous studies have shown that closely related heparin octasaccharides bind to Drosophila Robo directly, and surface plasmon resonance analysis revealed that Robo1 binds more tightly to full-length unfractionated heparin. For the first time, we utilized electron transfer dissociation-based high spatial resolution hydroxyl radical protein footprinting to identify two separate binding sites for heparin interaction with Robo1: one binding site at the previously identified site for heparin dp8 and a second binding site at the N terminus of Robo1 that is disordered in the x-ray crystal structure. Mutagenesis of the identified N-terminal binding site exhibited a decrease in binding affinity as measured by surface plasmon resonance and heparin affinity chromatography. Footprinting also indicated that heparin binding induces a minor change in the conformation and/or dynamics of the Ig2 domain, but no major conformational changes were detected. These results indicate a second low affinity binding site in the Robo-Slit complex as well as suggesting the role of the Ig2 domain of Robo1 in heparin-mediated signal transduction. This study also marks the first use of electron transfer dissociation-based high spatial resolution hydroxyl radical protein footprinting, which shows great utility for the characterization of protein-carbohydrate complexes. PMID:25752613
Belvedere, Raffaella; Bizzarro, Valentina; Parente, Luca; Petrella, Francesco; Petrella, Antonello
2018-03-04
Prisma® Skin is a new pharmaceutical device developed by Mediolanum Farmaceutici S.p.a. It includes alginates, hyaluronic acid and mainly mesoglycan. The latter is a natural glycosaminoglycan preparation containing chondroitin sulfate, dermatan sulfate, heparan sulfate and heparin and it is used in the treatment of vascular disease. Glycosaminoglycans may contribute to the re-epithelialization in the skin wound healing, as components of the extracellular matrix. Here we describe, for the first time, the effects of Prisma® Skin in in vitro cultures of adult epidermal keratinocytes and dermal fibroblasts. Once confirmed the lack of cytotoxicity by mesoglycan and Prisma® Skin, we have shown the increase of S and G2 phases of fibroblasts cell cycle distribution. We further report the strong induction of cell migration rate and invasion capability on both cell lines, two key processes of wound repair. In support of these results, we found significant cytoskeletal reorganization, following the treatments with mesoglycan and Prisma® Skin, as confirmed by the formation of F-actin stress fibers. Additionally, together with a significant reduction of E-cadherin, keratinocytes showed an increase of CD44 expression and the translocation of ezrin to the plasma membrane, suggesting the involvement of CD44/ERM (ezrin-radixin-moesin) pathway in the induction of the analyzed processes. Furthermore, as showed by immunofluorescence assay, fibroblasts treated with mesoglycan and Prisma® Skin exhibited the increase of Fibroblast Activated Protein α and a remarkable change in shape and orientation, two common features of reactive stromal fibroblasts. In all experiments Prisma® Skin was slightly more potent than mesoglycan. In conclusion, based on these findings we suggest that Prisma® Skin may be able to accelerate the healing process in venous skin ulcers, principally enhancing re-epithelialization and granulation processes.
Roy, Sashwati; Patel, Darshan; Khanna, Savita; Gordillo, Gayle M.; Biswas, Sabyasachi; Friedman, Avner; Sen, Chandan K.
2007-01-01
Chronic wounds represent a substantial public health problem. The development of tools that would enable sophisticated scrutiny of clinical wound tissue material is highly desirable. This work presents evidence enabling rapid specific identification and laser capture of blood vessels from human tissue in a manner which lends itself to successful high-density (U133A) microarray analysis. Such screening of transcriptome followed by real-time PCR and immunohistochemical verification of candidate genes and their corresponding products were performed by using 3 mm biopsies. Of the 18,400 transcripts and variants screened, a focused set of 53 up-regulated and 24 down-regulated genes were noted in wound-derived blood vessels compared with blood vessels from intact human skin. The mean abundance of periostin in wound-site blood vessels was 96-fold higher. Periostin is known to be induced in response to vascular injury and its expression is associated with smooth muscle cell differentiation in vitro and promotes cell migration. Forty-fold higher expression of heparan sulfate 6-O-endosulfatase1 (Sulf1) was noted in wound-site vessels. Sulf1 has been recently recognized to be anti-angiogenic. During embryonic vasculogenesis, CD24 expression is down-regulated in human embryonic stem cells. Wound-site vessels had lower CD24 expression. The findings of this work provide a unique opportunity to appreciate the striking contrast in the transcriptome composition in blood vessels collected from the intact skin and from the wound-edge tissue. Sets of genes with known vascular functions but never connected to wound healing were identified to be differentially expressed in wound-derived blood vessels paving the way for innovative clinically relevant hypotheses. PMID:17728400
Ang, Xiu Min; Lee, Michelle H.C.; Blocki, Anna; Chen, Clarice; Ong, L.L. Sharon; Asada, H. Harry; Sheppard, Allan
2014-01-01
The microenvironment plays a vital role in both the maintenance of stem cells in their undifferentiated state (niche) and their differentiation after homing into new locations outside this niche. Contrary to conventional in-vitro culture practices, the in-vivo stem cell microenvironment is physiologically crowded. We demonstrate here that re-introducing macromolecular crowding (MMC) at biologically relevant fractional volume occupancy during chemically induced adipogenesis substantially enhances the adipogenic differentiation response of human bone marrow-derived mesenchymal stem cells (MSCs). Both early and late adipogenic markers were significantly up-regulated and cells accumulated 25–40% more lipid content under MMC relative to standard induction cocktails. MMC significantly enhanced deposition of extracellular matrix (ECM), notably collagen IV and perlecan, a heparan sulfate proteoglycan. As a novel observation, MMC also increased the presence of matrix metalloproteinase −2 in the deposited ECM, which was concomitant with geometrical ECM remodeling typical of adipogenesis. This suggested a microenvironment that was richer in both matrix components and associated ligands and was conducive to adipocyte maturation. This assumption was confirmed by seeding undifferentiated MSCs on decellularized ECM deposited by adipogenically differentiated MSCs, Adipo-ECM. On Adipo-ECM generated under crowding, MSCs differentiated much faster under a classical differentiation protocol. This was evidenced throughout the induction time course, by a significant up-regulation of both early and late adipogenic markers and a 60% higher lipid content on MMC-generated Adipo-ECM in comparison to standard induction on tissue culture plastic. This suggests that MMC helps build and endow the nascent microenvironment with adipogenic cues. Therefore, MMC initiates a positive feedback loop between cells and their microenvironment as soon as progenitor cells are empowered to build and shape it, and, in turn, are informed by it to respond by attaining a stable differentiated phenotype if so induced. This work sheds new light on the utility of MMC to tune the microenvironment to augment the generation of adipose tissue from differentiating human MSCs. PMID:24147829
Weed, Darin J; Pritchard, Suzanne M; Gonzalez, Floricel; Aguilar, Hector C; Nicola, Anthony V
2017-03-01
Herpes simplex virus (HSV) entry into a subset of cells requires endocytosis and endosomal low pH. Preexposure of isolated virions to mildly acidic pH of 5 to 6 partially inactivates HSV infectivity in an irreversible manner. Acid inactivation is a hallmark of viruses that enter via low-pH pathways; this occurs by pretriggering conformational changes essential for fusion. The target and mechanism(s) of low-pH inactivation of HSV are unclear. Here, low-pH-treated HSV-1 was defective in fusion activity and yet retained normal levels of attachment to cell surface heparan sulfate and binding to nectin-1 receptor. Low-pH-triggered conformational changes in gB reported to date are reversible, despite irreversible low-pH inactivation. gB conformational changes and their reversibility were measured by antigenic analysis with a panel of monoclonal antibodies and by detecting changes in oligomeric conformation. Three-hour treatment of HSV-1 virions with pH 5 or multiple sequential treatments at pH 5 followed by neutral pH caused an irreversible >2.5 log infectivity reduction. While changes in several gB antigenic sites were reversible, alteration of the H126 epitope was irreversible. gB oligomeric conformational change remained reversible under all conditions tested. Altogether, our results reveal that oligomeric alterations and fusion domain changes represent distinct conformational changes in gB, and the latter correlates with irreversible low-pH inactivation of HSV. We propose that conformational change in the gB fusion domain is important for activation of membrane fusion during viral entry and that in the absence of a host target membrane, this change results in irreversible inactivation of virions. IMPORTANCE HSV-1 is an important pathogen with a high seroprevalence throughout the human population. HSV infects cells via multiple pathways, including a low-pH route into epithelial cells, the primary portal into the host. HSV is inactivated by low-pH preexposure, and gB, a class III fusion protein, undergoes reversible conformational changes in response to low-pH exposure. Here, we show that low-pH inactivation of HSV is irreversible and due to a defect in virion fusion activity. We identified an irreversible change in the fusion domain of gB following multiple sequential low-pH exposures or following prolonged low-pH treatment. This change appears to be separable from the alteration in gB quaternary structure. Together, the results are consistent with a model by which low pH can have an activating or inactivating effect on HSV depending on the presence of a target membrane. Copyright © 2017 American Society for Microbiology.
Bandyopadhyay, Chirosree; Veettil, Mohanan Valiya; Dutta, Sujoy; Chandran, Bala
2014-12-01
Kaposi's sarcoma-associated herpesvirus (KSHV) interacts with cell surface receptors, such as heparan sulfate, integrins (α3β1, αVβ3, and αVβ5), and EphrinA2 (EphA2), and activates focal adhesion kinase (FAK), Src, phosphoinositol 3-kinase (PI3-K), c-Cbl, and RhoA GTPase signal molecules early during lipid raft (LR)-dependent productive macropinocytic entry into human dermal microvascular endothelial cells. Our recent studies have identified CIB1 as a signal amplifier facilitating EphA2 phosphorylation and subsequent cytoskeletal cross talk during KSHV macropinocytosis. Although CIB1 lacks an enzymatic activity and traditional adaptor domain or known interacting sequence, it associated with the KSHV entry signal complex and the CIB1-KSHV association was sustained over 30 min postinfection. To identify factors scaffolding the EphA2-CIB1 signal axis, the role of major cellular scaffold protein p130Cas (Crk-associated substrate of Src) was investigated. Inhibitor and small interfering RNA (siRNA) studies demonstrated that KSHV induced p130Cas in an EphA2-, CIB1-, and Src-dependent manner. p130Cas and Crk were associated with KSHV, LRs, EphA2, and CIB1 early during infection. Live-cell microscopy and biochemical studies demonstrated that p130Cas knockdown did not affect KSHV entry but significantly reduced productive nuclear trafficking of viral DNA and routed KSHV to lysosomal degradation. p130Cas aided in scaffolding adaptor Crk to downstream guanine nucleotide exchange factor phospho-C3G possibly to coordinate GTPase signaling during KSHV trafficking. Collectively, these studies demonstrate that p130Cas acts as a bridging molecule between the KSHV-induced entry signal complex and the downstream trafficking signalosome in endothelial cells and suggest that simultaneous targeting of KSHV entry receptors with p130Cas would be an attractive potential avenue for therapeutic intervention in KSHV infection. Eukaryotic cell adaptor molecules, without any intrinsic enzymatic activity, are well known to allow a great diversity of specific and coordinated protein-protein interactions imparting signal amplification to different networks for physiological and pathological signaling. They are involved in integrating signals from growth factors, extracellular matrix molecules, bacterial pathogens, and apoptotic cells. The present study identifies human microvascular dermal endothelial (HMVEC-d) cellular scaffold protein p130Cas (Crk-associated substrate) as a platform to promote Kaposi's sarcoma-associated herpesvirus (KSHV) trafficking. Early during KSHV de novo infection, p130Cas associates with lipid rafts and scaffolds EphrinA2 (EphA2)-associated critical adaptor members to downstream effector molecules, promoting successful nuclear delivery of the KSHV genome. Hence, simultaneous targeting of the receptor EphA2 and scaffolding action of p130Cas can potentially uncouple the signal cross talk of the KSHV entry-associated upstream signal complex from the immediate downstream trafficking-associated signalosome, consequently routing KSHV toward lysosomal degradation and eventually blocking KSHV infection and associated malignancies. Copyright © 2014, American Society for Microbiology. All Rights Reserved.
Iwami, Daiki; Brinkman, C Colin; Bromberg, Jonathan S
2015-04-01
Circulation of leukocytes via blood, tissue and lymph is integral to adaptive immunity. Afferent lymphatics form CCL21 gradients to guide dendritic cells and T cells to lymphatics and then to draining lymph nodes (dLN). Vascular endothelial growth factor C and vascular endothelial growth factor receptor 3 (VEGFR-3) are the major lymphatic growth factor and receptor. We hypothesized these molecules also regulate chemokine gradients and lymphatic migration. CD4 T cells were injected into the foot pad or ear pinnae, and migration to afferent lymphatics and dLN quantified by flow cytometry or whole mount immunohistochemistry. Vascular endothelial growth factor receptor 3 or its signaling or downstream actions were modified with blocking monoclonal antibodies (mAbs) or other reagents. Anti-VEGFR-3 prevented migration of CD4 T cells into lymphatic lumen and significantly decreased the number that migrated to dLN. Anti-VEGFR-3 abolished CCL21 gradients around lymphatics, although CCL21 production was not inhibited. Heparan sulfate (HS), critical to establish CCL21 gradients, was down-regulated around lymphatics by anti-VEGFR-3 and this was dependent on heparanase-mediated degradation. Moreover, a Phosphoinositide 3-kinase (PI3K)α inhibitor disrupted HS and CCL21 gradients, whereas a PI3K activator prevented the effects of anti-VEGFR-3. During contact hypersensitivity, VEGFR-3, CCL21, and HS expression were all attenuated, and anti-heparanase or PI3K activator reversed these effects. Vascular endothelial growth factor C/VEGFR-3 signaling through PI3Kα regulates the activity of heparanase, which modifies HS and CCL21 gradients around lymphatics. The functional and physical linkages of these molecules regulate lymphatic migration from tissues to dLN. These represent new therapeutic targets to influence immunity and inflammation.
AGE-RELATED FUNCTIONAL AND HISTOPATHOLOGICAL CHANGES OF THE EAR IN THE MPS I MOUSE
Schachern, Patricia A.; Cureoglu, Sebahattin; Tsuprun, Vladimir; Paparella, Michael M.; Whitley, Chester
2007-01-01
Objective Mucopolysaccharidosis type I (MPS I) is an autosomal recessive disorder caused by a mutation in the gene encoding the enzyme α-L-iduronidase. This enzyme is responsible for degradation of dermatan and heparan sulfates. Enzyme deficiency results in their accumulation in lysosomes of virtually all organs, resulting in severe somatic and neurological changes. Clinical findings of otitis media with mixed hearing loss are common. Cellular and molecular mechanisms of ear pathology and hearing loss are not understood. The purpose of this study is to describe the age-related audiologic and histopathologic changes of the ear in the mouse model of MPS I. Methods Auditory brainstemresponses (ABR) were obtained to clicks and tone bursts at 1-32 kHz, and pathological changes to middle and inner ears were studied with light and electron microscopy in fifty-three mice that included: 1) wild type (+/+) - five at 2 months, five at 4 to 6 months, and five at 13 to 19 months; 2) heterozygotes (+/−) - four at 2 months; five at 4 to 6 months; and eight at 13 to 19 months; and 3) homozygotes (−/−); five at 2 months; six at 4 to 6 months; and five at 13 to 19 months. Histopathology was also done on five newborn −/− mice. Results In newborns no lysosomal storage was observed and the ear appeared age appropriately normal. In all other −/− mice, cells with lysosomal storage vacuoles were observed in spiral ligament, spiral prominence, spiral limbus, basilar membrane, epithelial and mesothelial cells of Reissner’s membrane, endothelial cells of vessels, and some ganglion cells; their number increased with aging. Hair cell loss was not observed at 2 or 6 months, but there was total loss of the organ of Corti in year-old mice. Hearing of −/− mice was significantly decreased at all ages compared to +/+ and +/−. Hearing loss progressed from mild to moderate loss at 2 months to profound at 6 months and total deafness by one year of age. Conclusions Progressive age-related changes suggest early therapeutic intervention to prevent sensory cell damage and hearing loss. PMID:17101178
Minniti, Alicia N; Labarca, Mariana; Hurtado, Claudia; Brandan, Enrique
2004-10-01
In Caenorhabditis elegans, the identification of many enzymes involved in the synthesis and modification of glycosaminoglycans (GAGs), essential components of proteoglycans, has attained special attention in recent years. Mutations in all the genes that encode for GAG biosynthetic enzymes show defects in the development of the vulva, specifically in the invagination of the vulval epithelium. Mutants for certain heparan sulfate modifying enzymes present axonal and cellular guidance defects in specific neuronal classes. Although most of the enzymes involved in the biosynthesis and modification of heparan sulfate have been characterized in C. elegans, little is known regarding the core proteins to which these GAGs covalently bind in proteoglycans. A single syndecan homologue (sdn-1) has been identified in the C. elegans genome through sequence analysis. In the present study, we show that C. elegans synthesizes sulfated proteoglycans, seen as three distinct species in western blot analysis. In the sdn-1 (ok449) deletion mutant allele we observed the lack of one species, which corresponds to a 50 kDa product after heparitinase treatment. The expression of sdn-1 mRNA and sequencing revealed that sdn-1 (ok449) deletion mutants lack two glycosylation sites. Hence, the missing protein in the western blot analysis probably corresponds to SDN-1. In addition, we show that SDN-1 localizes to the C. elegans nerve ring, nerve cords and to the vulva. SDN-1 is found specifically phosphorylated in nerve ring neurons and in the vulva, in both wild-type worms and sdn-1 (ok449) deletion mutants. These mutants show a defective egg-laying phenotype. Our results show for the first time, the identification, localization and some functional aspects of syndecan in the nematode C. elegans.
Gysi, Stephan; Rhiner, Christa; Flibotte, Stephane; Moerman, Donald G.; Hengartner, Michael O.
2013-01-01
Heparan sulfate proteoglycans (HSPGs) are proteins with long covalently attached sugar side chains of the heparan sulfate (HS) type. Depending on the cellular context HS chains carry multiple structural modifications such as sulfate residues or epimerized sugars allowing them to bind to a wide range of molecules. HSPGs have been found to play extremely diverse roles in animal development and were shown to interact with certain axon guidance molecules. In this study we describe the role of the Caenorhabditis elegans HSPG core proteins Syndecan (SDN-1) and Glypican (LON-2) and the HS modifying enzymes in the dorsal guidance of D-type motor axons, a process controlled mainly by the conserved axon guidance molecule UNC-6/Netrin. Our genetic analysis established the specific HS code relevant for this axon guidance event. Using two sensitized genetic backgrounds, we isolated novel components influencing D-type motor axon guidance with a link to HSPGs, as well as new alleles of several previously characterized axon guidance genes. Interestingly, the dorsal axon guidance defects induced by mutations in zfp-1 or lin-35 depended on the transgene oxIs12 used to visualize the D-type motor neurons. oxIs12 is a large multi-copy transgene that enlarges the X chromosome by approximately 20%. In a search for genes with a comparable phenotype we found that a mutation in the known dosage compensation gene dpy-21 showed similar axon guidance defects as zfp-1 or lin-35 mutants. Thus, derepression of genes on X, where many genes relevant for HS dependent axon guidance are located, might also influence axon guidance of D-type motor neurons. PMID:24066155
Myette, James R; Soundararajan, Venkataramanan; Shriver, Zachary; Raman, Rahul; Sasisekharan, Ram
2009-12-11
Heparin and heparan sulfate glycosaminoglycans (HSGAGs) comprise a chemically heterogeneous class of sulfated polysaccharides. The development of structure-activity relationships for this class of polysaccharides requires the identification and characterization of degrading enzymes with defined substrate specificity and enzymatic activity. Toward this end, we report here the molecular cloning and extensive structure-function analysis of a 6-O-sulfatase from the Gram-negative bacterium Flavobacterium heparinum. In addition, we report the recombinant expression of this enzyme in Escherichia coli in a soluble, active form and identify it as a specific HSGAG sulfatase. We further define the mechanism of action of the enzyme through biochemical and structural studies. Through the use of defined substrates, we investigate the kinetic properties of the enzyme. This analysis was complemented by homology-based molecular modeling studies that sought to rationalize the substrate specificity of the enzyme and mode of action through an analysis of the active-site topology of the enzyme including identifying key enzyme-substrate interactions and assigning key amino acids within the active site of the enzyme. Taken together, our structural and biochemical studies indicate that 6-O-sulfatase is a predominantly exolytic enzyme that specifically acts on N-sulfated or N-acetylated 6-O-sulfated glucosamines present at the non-reducing end of HSGAG oligosaccharide substrates. This requirement for the N-acetyl or N-sulfo groups on the glucosamine substrate can be explained through eliciting favorable interactions with key residues within the active site of the enzyme. These findings provide a framework that enables the use of 6-O-sulfatase as a tool for HSGAG structure-activity studies as well as expand our biochemical and structural understanding of this important class of enzymes.
Dadoukis, Panagiotis; Klagas, Ioannis; Komnenou, Anastasia; Karakiulakis, George; Karoutis, Athanasios; Karampatakis, Vassilios; Papakonstantinou, Eleni
2013-08-01
Prolonged exposure to infrared (IR) radiation is associated with different types of damage to cornea and lens. The aim of our study was to investigate the effect of acute and chronic exposure to IR radiation on the activity of matrix metalloproteinase-2 (MMP-2) and MMP-9 and on the expression of glycosaminoglycans (GAG) in the rabbit cornea and crystalline lens. New Zealand rabbits were subjected to IR radiation for 4 months (chronic exposure to IR) or to normal light (control group). In experiments regarding acute exposure, animals were subjected to IR radiation or normal light for 12 h, in the presence of 0.1% diclofenac sodium (eye drops instilled in the right eye of animals) or saline (instilled in the left eye of animals). The cornea and lens were dissected away and homogenized. The activity of MMP-2 and MMP-9 was assayed by gelatine zymography. Total GAG were isolated from tissue specimens after lipid extraction and extensive digestion with pronase and DNase and characterized by treatment with GAG-degrading enzymes, followed by electrophoresis on cellulose acetate membranes. Acute or chronic exposure to IR radiation induced the activity of MMP-2 in cornea and lens, whereas only acute IR radiation increased the content of heparan sulphate in crystalline lens. Local administration of diclofenac sodium did not prevent the above effects of acute IR radiation. The detrimental effects of excessive or prolonged exposure of the eyes to IR radiation are associated with induced activity of MMP-2 in cornea and lens and alterations in the content of heparan sulphate in lens. Thus, MMP and GAG may offer alternative targets for pharmacological intervention to confront ocular damages associated with IR radiation.
NASA Astrophysics Data System (ADS)
Shi, Xiaofeng; Huang, Yu; Mao, Yang; Naimy, Hicham; Zaia, Joseph
2012-09-01
Heparan sulfate (HS) is a polysaccharide modified with sulfation, acetylation, and epimerization that enable its binding with protein ligands and regulation of important biological processes. Tandem mass spectrometry has been employed to sequence linear biomolecules e.g., proteins and peptides. However, its application in structural characterization of HS is limited due to the neutral loss of sulfate (SO3) during collisional induced dissociation (CID). In this report, we studied the dissociation patterns of HS disaccharides and demonstrate that the N-sulfate (N-S) bond is especially facile during CID. We identified factors that influence the propensities of such losses from precursor ions and proposed a Free Proton Index (FPI) to help select ions that are able to produce meaningful backbone dissociations. We then investigated the thermodynamics and kinetics of SO3 loss from sulfates that are protonated, deprotonated, and metal-adducted using density functional theory computations. The calculations showed that sulfate loss from a protonated site was much more facile than that from a deprotonated or metal-adducted site. Further, the loss of SO3 from N-sulfate was energetically favored by 3-8 kcal/mol in transition states relative to O-sulfates, making it more prone to this process by a substantial factor. In order to reduce the FPI, representing the number of labile sulfates in HS native chains and oligosaccharides, we developed a series of chemical modifications to selectively replace the N-sulfates of the glucosamine with deuterated acetyl group. These modifications effectively reduced the sulfate density on the HS oligosaccharides and generated considerably more backbone dissociation using on-line LC/tandem MS.
Association of HS6ST3 gene polymorphisms with obesity and triglycerides: gene x gender interaction.
Wang, Ke-Sheng; Wang, Liang; Liu, Xuefeng; Zeng, Min
2013-12-01
The heparan sulfate 6-O-sulfotransferase 3 (HS6ST3) gene is involved in heparan sulphate and heparin metabolism, and has been reported to be associated with diabetic retinopathy in type 2 diabetes.We hypothesized that HS6ST3 gene polymorphisms might play an important role in obesity and related phenotypes (such as triglycerides). We examined genetic associations of 117 single-nucleotide polymorphisms (SNPs) within the HS6ST3 gene with obesity and triglycerides using two Caucasian samples: the Marshfield sample (1442 obesity cases and 2122 controls), and the Health aging and body composition (Health ABC) sample (305 cases and 1336 controls). Logistic regression analysis of obesity as a binary trait and linear regression analysis of triglycerides as a continuous trait, adjusted for age and sex, were performed using PLINK. Single marker analysis showed that six SNPs in the Marshfield sample and one SNP in the Health ABC sample were associated with obesity (P < 0.05). SNP rs535812 revealed a stronger association with obesity in meta-analysis of these two samples (P = 0.0105). The T-A haplotype from rs878950 and rs9525149 revealed significant association with obesity in the Marshfield sample (P = 0.012). Moreover, nine SNPs showed associations with triglycerides in the Marshfield sample (P < 0.05) and the best signal was rs1927796 (P = 0.00858). In addition, rs7331762 showed a strong gene x gender interaction (P = 0.00956) for obesity while rs1927796 showed a strong gene x gender interaction (P = 0.000625) for triglycerides in the Marshfield sample. These findings contribute new insights into the pathogenesis of obesity and triglycerides and demonstrate the importance of gender differences in the aetiology.
The Effect of Milk Constituents and Crowding Agents on Amyloid Fibril Formation by κ-Casein.
Liu, Jihua; Dehle, Francis C; Liu, Yanqin; Bahraminejad, Elmira; Ecroyd, Heath; Thorn, David C; Carver, John A
2016-02-17
When not incorporated into the casein micelle, κ-casein, a major milk protein, rapidly forms amyloid fibrils at physiological pH and temperature. In this study, the effects of milk components (calcium, lactose, lipids, and heparan sulfate) and crowding agents on reduced and carboxymethylated (RCM) κ-casein fibril formation was investigated using far-UV circular dichroism spectroscopy, thioflavin T binding assays, and transmission electron microscopy. Longer-chain phosphatidylcholine lipids, which form the lining of milk ducts and milk fat globules, enhanced RCM κ-casein fibril formation irrespective of whether the lipids were in a monomeric or micellar state, whereas shorter-chain phospholipids and triglycerides had little effect. Heparan sulfate, a component of the milk fat globule membrane and catalyst of amyloid deposition in extracellular tissue, had little effect on the kinetics of RCM κ-casein fibril formation. Major nutritional components such as calcium and lactose also had no significant effect. Macromolecular crowding enhances protein-protein interactions, but in contrast to other fibril-forming species, the extent of RCM κ-casein fibril formation was reduced by the presence of a variety of crowding agents. These data are consistent with a mechanism of κ-casein fibril formation in which the rate-determining step is dissociation from the oligomer to give the highly amyloidogenic monomer. We conclude that the interaction of κ-casein with membrane-associated phospholipids along its secretory pathway may contribute to the development of amyloid deposits in mammary tissue. However, the formation of spherical oligomers such as casein micelles is favored over amyloid fibrils in the crowded environment of milk, within which the occurrence of amyloid fibrils is low.
Elevation of glycosaminoglycans in the amniotic fluid of a fetus with mucopolysaccharidosis VII
Kubaski, Francyne; Brusius-Facchin, Ana Carolina; Mason, Robert W.; Patel, Pravin; Burin, Maira G.; Michelin-Tirelli, Kristiane; Kessler, Rejane Gus; Bender, Fernanda; Leistner-Segal, Sandra; Moreno, Carolina A.; Cavalcanti, Denise P.; Giugliani, Roberto; Tomatsu, Shunji
2017-01-01
Objective The aim of this study was to quantify GAGs in amniotic fluid (AF) from an MPS VII fetus compared with age-matched fetuses obtained from normal pregnancies. Method Disaccharides were measured by liquid chromatography tandem mass spectrometry (LC/MS/MS), compared to age-matched controls. Enzyme assay was performed in AF supernatant or cultured amniocytes. GUSB was analyzed by next generation sequencing using Ion Torrent Personal Genome Machine with a customized panel. Results No activity of β-glucuronidase was detected in fetal cells. The pregnancy was spontaneously terminated in the third trimester. Genetic studies identified a homozygous mutation of p.N379D (c.1135A>G) in the GUSB gene. LC/MS/MS showed that chondroitin sulfate, dermatan sulfate, heparan sulfate, and keratan sulfate levels were markedly increased in the MPS VII AF, compared to those in age-matched control AF (DS, HS, and C6S more than 10 × than age-matched controls; C4S and KS more than 3 times higher). Conclusion This is the first report of specific GAG analysis in AF from an MPS VII fetus, indicating that GAG elevation in AF occurs by 21 weeks of gestation and could be an additional tool for prenatal diagnosis of MPS VII and potentially other MPS types. PMID:28207930
Heparin-binding epidermal growth factor-like growth factor promotes neuroblastoma differentiation.
Gaviglio, Angela L; Knelson, Erik H; Blobe, Gerard C
2017-05-01
High-risk neuroblastoma is characterized by undifferentiated neuroblasts and low schwannian stroma content. The tumor stroma contributes to the suppression of tumor growth by releasing soluble factors that promote neuroblast differentiation. Here we identify heparin-binding epidermal growth factor-like growth factor (HBEGF) as a potent prodifferentiating factor in neuroblastoma. HBEGF mRNA expression is decreased in human neuroblastoma tumors compared with benign tumors, with loss correlating with decreased survival. HBEGF protein is expressed only in stromal compartments of human neuroblastoma specimens, with tissue from high-stage disease containing very little stroma or HBEGF expression. In 3 human neuroblastoma cell lines (SK-N-AS, SK-N-BE2, and SH-SY5Y), soluble HBEGF is sufficient to promote neuroblast differentiation and decrease proliferation. Heparan sulfate proteoglycans and heparin derivatives further enhance HBEGF-induced differentiation by forming a complex with the epidermal growth factor receptor, leading to activation of the ERK1/2 and STAT3 pathways and up-regulation of the inhibitor of DNA binding transcription factor. These data support a role for loss of HBEGF in the neuroblastoma tumor microenvironment in neuroblastoma pathogenesis.-Gaviglio, A. L., Knelson, E. H., Blobe, G. C. Heparin-binding epidermal growth factor-like growth factor promotes neuroblastoma differentiation. © FASEB.
Heparin-binding epidermal growth factor-like growth factor promotes neuroblastoma differentiation
Gaviglio, Angela L.; Knelson, Erik H.; Blobe, Gerard C.
2017-01-01
High-risk neuroblastoma is characterized by undifferentiated neuroblasts and low schwannian stroma content. The tumor stroma contributes to the suppression of tumor growth by releasing soluble factors that promote neuroblast differentiation. Here we identify heparin-binding epidermal growth factor–like growth factor (HBEGF) as a potent prodifferentiating factor in neuroblastoma. HBEGF mRNA expression is decreased in human neuroblastoma tumors compared with benign tumors, with loss correlating with decreased survival. HBEGF protein is expressed only in stromal compartments of human neuroblastoma specimens, with tissue from high-stage disease containing very little stroma or HBEGF expression. In 3 human neuroblastoma cell lines (SK-N-AS, SK-N-BE2, and SH-SY5Y), soluble HBEGF is sufficient to promote neuroblast differentiation and decrease proliferation. Heparan sulfate proteoglycans and heparin derivatives further enhance HBEGF-induced differentiation by forming a complex with the epidermal growth factor receptor, leading to activation of the ERK1/2 and STAT3 pathways and up-regulation of the inhibitor of DNA binding transcription factor. These data support a role for loss of HBEGF in the neuroblastoma tumor microenvironment in neuroblastoma pathogenesis.—Gaviglio, A. L., Knelson, E. H., Blobe, G. C. Heparin-binding epidermal growth factor-like growth factor promotes neuroblastoma differentiation. PMID:28174207
Marcello, Marco
2016-01-01
The range of biological outcomes generated by many signalling proteins in development and homeostasis is increased by their interactions with glycosaminoglycans, particularly heparan sulfate (HS). This interaction controls the localization and movement of these signalling proteins, but whether such control depends on the specificity of the interactions is not known. We used five fibroblast growth factors with an N-terminal HaloTag (Halo-FGFs) for fluorescent labelling, with well-characterized and distinct HS-binding properties, and measured their binding and diffusion in pericellular matrix of fixed rat mammary 27 fibroblasts. Halo-FGF1, Halo-FGF2 and Halo-FGF6 bound to HS, whereas Halo-FGF10 also interacted with chondroitin sulfate/dermatan sulfate, and FGF20 did not bind detectably. The distribution of bound FGFs in the pericellular matrix was not homogeneous, and for FGF10 exhibited striking clusters. Fluorescence recovery after photobleaching showed that FGF2 and FGF6 diffused faster, whereas FGF1 diffused more slowly, and FGF10 was immobile. The results demonstrate that the specificity of the interactions of proteins with glycosaminoglycans controls their binding and diffusion. Moreover, cells regulate the spatial distribution of different protein-binding sites in glycosaminoglycans independently of each other, implying that the extracellular matrix has long-range structure. PMID:27009190
Akl, Mohamed R.; Nagpal, Poonam; Ayoub, Nehad M.; Tai, Betty; Prabhu, Sathyen A.; Capac, Catherine M.; Gliksman, Matthew; Goy, Andre; Suh, K. Stephen
2016-01-01
Fibroblast growth factor (FGF) signaling is essential for normal and cancer biology. Mammalian FGF family members participate in multiple signaling pathways by binding to heparan sulfate and FGF receptors (FGFR) with varying affinities. FGF2 is the prototype member of the FGF family and interacts with its receptor to mediate receptor dimerization, phosphorylation, and activation of signaling pathways, such as Ras-MAPK and PI3K pathways. Excessive mitogenic signaling through the FGF/FGFR axis may induce carcinogenic effects by promoting cancer progression and increasing the angiogenic potential, which can lead to metastatic tumor phenotypes. Dysregulated FGF/FGFR signaling is associated with aggressive cancer phenotypes, enhanced chemotherapy resistance and poor clinical outcomes. In vitro experimental settings have indicated that extracellular FGF2 affects proliferation, drug sensitivity, and apoptosis of cancer cells. Therapeutically targeting FGF2 and FGFR has been extensively assessed in multiple preclinical studies and numerous drugs and treatment options have been tested in clinical trials. Diagnostic assays are used to quantify FGF2, FGFRs, and downstream signaling molecules to better select a target patient population for higher efficacy of cancer therapies. This review focuses on the prognostic significance of FGF2 in cancer with emphasis on therapeutic intervention strategies for solid and hematological malignancies. PMID:27007053
Magruder, Hilary T.; Quinn, Jeffrey A.; Schwartzbauer, Jean E.; Reichner, Jonathan; Huang, Allan
2016-01-01
The G protein-coupled estrogen receptor-1, GPER-1, coordinates fibronectin (FN) matrix assembly and release of heparan-bound epidermal growth factor (HB-EGF). This mechanism of action results in the recruitment of FN-engaged integrin α5β1 to fibrillar adhesions and the formation of integrin α5β1-Shc adaptor protein complexes. Here, we show that GPER-1 stimulation of murine 4 T1 or human SKBR3 breast cancer cells with 17β-estradiol (E2β) promotes the formation of focal adhesions and actin stress fibers and results in increased cellular adhesion and haptotaxis on FN, but not collagen. These actions are also induced by the xenoestrogen, bisphenol A, and the estrogen receptor (ER) antagonist, ICI 182, 780, but not the inactive stereoisomer, 17α-estradiol (E2α). In addition, we show that GPER-1 stimulation of breast cancer cells allows for FN-dependent, anchorage-independent growth and FN fibril formation in “hanging drop” assays, indicating that these GPER-1-mediated actions occur independently of adhesion to solid substrata. Stable expression of Shc mutant Y317F lacking its primary tyrosyl phosphorylation site disrupts E2β-induced focal adhesion and actin stress fiber formation and abolishes E2β-enhanced haptotaxis on FN and anchorage-dependent growth. Collectively, these data demonstrate that E2β action via GPER-1 enhances cellular adhesivity and FN matrix assembly and allows for anchorage-independent growth, cellular events that may allow for cellular survival, and tumor progression. PMID:25096985
Brain Extracellular Space: The Final Frontier of Neuroscience.
Nicholson, Charles; Hrabětová, Sabina
2017-11-21
Brain extracellular space is the narrow microenvironment that surrounds every cell of the central nervous system. It contains a solution that closely resembles cerebrospinal fluid with the addition of extracellular matrix molecules. The space provides a reservoir for ions essential to the electrical activity of neurons and forms an intercellular chemical communication channel. Attempts to reveal the size and structure of the extracellular space using electron microscopy have had limited success; however, a biophysical approach based on diffusion of selected probe molecules has proved useful. A point-source paradigm, realized in the real-time iontophoresis method using tetramethylammonium, as well as earlier radiotracer methods, have shown that the extracellular space occupies ∼20% of brain tissue and small molecules have an effective diffusion coefficient that is two-fifths that in a free solution. Monte Carlo modeling indicates that geometrical constraints, including dead-space microdomains, contribute to the hindrance to diffusion. Imaging the spread of macromolecules shows them increasingly hindered as a function of size and suggests that the gaps between cells are predominantly ∼40 nm with wider local expansions that may represent dead-spaces. Diffusion measurements also characterize interactions of ions and proteins with the chondroitin and heparan sulfate components of the extracellular matrix; however, the many roles of the matrix are only starting to become apparent. The existence and magnitude of bulk flow and the so-called glymphatic system are topics of current interest and controversy. The extracellular space is an exciting area for research that will be propelled by emerging technologies. Copyright © 2017 Biophysical Society. Published by Elsevier Inc. All rights reserved.
Ling, Ling; Tan, Si Kee; Goh, Ting Hwee; Cheung, Edwin; Nurcombe, Victor; van Wijnen, Andre J; Cool, Simon M
2015-07-23
Aberrant activation of fibroblast growth factor receptors (FGFRs) deregulates cell proliferation and promotes cell survival, and may predispose to tumorigenesis. Therefore, selective inactivation of FGFRs is an important strategy for cancer therapy. Here as a proof-of-concept study, we developed a FGFR1 neutralizing antisera, IMB-R1, employing a novel strategy aimed at preventing the access of essential heparan sulfate (HS) co-receptors to the heparin-binding domain on FGFR1. The mRNA and protein expression level of FGFR1 and other FGFRs were examined in several lines of breast cancer and osteosarcoma cells and corresponding normal cells using Taqman real-time quantitative PCR and Western blot analysis. The specificity of IMB-R1 against FGFR1 was assessed with various ELISA-based approaches and Receptor Tyrosine Kinase array. Proliferation assay and apoptosis analysis were performed to assess the effect of IMB-R1 on cancer cell growth and apoptosis, respectively, in comparison with known FGFR1 inhibitors. The IMB-R1 induced alteration of intracellular signaling and gene expression were analysed using Western blot and microarray approaches. Immunohistochemical staining of FGFR1 using IMB-R1 were carried out in different cancer tissues from clinical patients. Throughout the study, statistical differences were determined by Student's t test where appropriate and reported when a p value was less than 0.05. We demonstrate that IMB-R1 is minimally cross-reactive for other FGFRs, and that it potently and specifically inhibits binding of heparin to FGFR1. Furthermore, IMB-R1 blocks the interaction of FGF2 with FGFR1, the kinase activity of FGFR1 and activation of intracellular FGFR signaling. Cancer cells treated with IMB-R1 displayed impaired FGF2 signaling, were unable to grow and instead underwent apoptosis. IMB-R1-induced cell death correlated with a disruption of antioxidative defense networks and increased expression of several tumor suppressors and apoptotic proteins, including p53. Immunostaining with IMB-R1 was stronger in human cancer tissues in which the FGFR1 gene is amplified. Our study suggests that blocking HS interaction with the heparin-binding domains of FGFR1 inhibited cancer cell growth, which can be an attractive strategy to inactivate cancer-related heparin-binding proteins.
Cheng, You-Hong; Eby, Jonathan M; LaPorte, Heather M; Volkman, Brian F; Majetschak, Matthias
2017-01-01
Recent evidence suggests that chemokine CXCL12, the cognate agonist of chemokine receptors CXCR4 and ACKR3, reduces thrombin-mediated impairment of endothelial barrier function. A detailed characterization of the effects of CXCL12 on thrombin-mediated human lung endothelial hyperpermeability is lacking and structure-function correlations are not available. Furthermore, effects of other CXCR4/ACKR3 ligands on lung endothelial barrier function are unknown. Thus, we tested the effects of a panel of CXCR4/ACKR3 ligands (CXCL12, CXCL11, ubiquitin, AMD3100, TC14012) and compared the CXCR4/ACKR3 activities of CXCL12 variants (CXCL12α/β, CXCL12(3-68), CXCL121, CXCL122, CXCL12-S-S4V, CXCL12-R47E, CXCL12-K27A/R41A/R47A) with their effects on human lung endothelial barrier function in permeability assays. CXCL12α enhanced human primary pulmonary artery endothelial cell (hPPAEC) barrier function, whereas CXCL11, ubiquitin, AMD3100 and TC14012 were ineffective. Pre-treatment of hPPAEC with CXCL12α and ubiquitin reduced thrombin-mediated hyperpermeability. CXCL12α-treatment of hPPAEC after thrombin exposure reduced barrier function impairment by 70% (EC50 0.05-0.5nM), which could be antagonized with AMD3100; ubiquitin (0.03-3μM) was ineffective. In a human lung microvascular endothelial cell line (HULEC5a), CXCL12α and ubiquitin post-treatment attenuated thrombin-induced hyperpermeability to a similar degree. CXCL12(3-68) was inefficient to activate CXCR4 in Presto-Tango β-arrestin2 recruitment assays; CXCL12-S-S4V, CXCL12-R47E and CXCL12-K27A/R41A/R47A showed significantly reduced potencies to activate CXCR4. While the potencies of all proteins in ACKR3 Presto-Tango assays were comparable, the efficacy of CXCL12(3-68) to activate ACKR3 was significantly reduced. The potencies to attenuate thrombin-mediated hPPAEC barrier function impairment were: CXCL12α/β, CXCL121, CXCL12-K27A/R41A/R47A > CXCL12-S-S4V, CXCL12-R47E > CXCL122 > CXCL12(3-68). Our findings indicate that CXCR4 activation attenuates thrombin-induced lung endothelial barrier function impairment and suggest that protective effects of CXCL12 are dictated by its CXCR4 agonist activity and interactions of distinct protein moieties with heparan sulfate on the endothelial surface. These data may facilitate development of compounds with improved pharmacological properties to attenuate thrombin-induced vascular leakage in the pulmonary circulation.
Stone, A L; Melton, D J; Lewis, M S
1998-07-01
Heparins/heparan sulfates modulate the function of proteins and cell membranes in numerous biological systems including normal and disease processes in humans. Heparin has been used for many years as an anticoagulant, and anticoagulant heparin-mimetics were developed several decades ago by chemical sulfation of non-mammalian polysaccharides, e.g., an antithrombotic sulfated xylan. This pharmaceutical, which comprises a mixture of sulfated oligoxylans, also mimics most other biological actions of natural heparins in vitro, including inhibition of the human immunodeficiency virus, but the molecular basis for these actions has been unclear. Here, numerous Components of the sulfated oligoxylan mixture were isolated and when bioassayed in the case of anti-HIV-1 infectivity revealed that a structural specificity underlines the capacity of sulfated xylan to inhibit HIV-1, rather than a non-specific mechanism. Components were isolated by chromatographic fractionation through Bio-Gel P10 in 0.5 M ammonium bicarbonate. This fractionation revealed an elution range associated with apparent molecular weights of approximately 22000 to <1500 relative to standard heparin and heparan sulfates and newly prepared sulfated oligosaccharide standards. Components were characterized by metachromatic absorption spectroscopy, ultracentrifugation, GlcA analysis, and potency against HIV-1 infectivity, both in the tetrazolium cytotoxicity assay and in syncytium-forming assays, in CD4-lymphocytes. Structural specificity was indicated by the differential potencies exhibited by the Components: Highest activity (cytotoxicity) was exhibited by Components in the chromatographic region > or = approximately 5500 in mass (50% effective (inhibitory) concentration = 0.5-0.7 microg ml(-1) in the first fractionation series, and 0.1-0.5 microg ml(-1) in a second series). The potency declined sharply below approximately 5400 in mass, but with an exception; a second structure exhibiting relatively high potency eluted among low-mass oligosaccharides which had an average size of approximately a nonomer. Components displayed differential potencies also against the syncytium-forming infectivity of HIV-1. The high potency against syncytium-formation was retained by Components down to a minimum size of about 4500 in mass, smaller than the > or = approximately 5400 required above. One in ten of the beta1,4-linked xyloses in the native xylan are substituted with a monomeric alpha1,2 DGlcA branch. We have speculated that pharmaceutical actions of sulfated xylan might be related to structures involving the alpha-D linked substituents and this was examined using a space-filling model of a sulfated octaxylan and by analyses of Components for GlcA content. Understanding structure/function relations in the heparin-like actions of these agents would be of general significance for the careful examination of their potential clinical usefulness in many human processes modulated by heparins, including AIDS.
Dyksterhuis, L.D.; White, J.F.; Hickey, M.; Kirby, N.; Mudie, S.; Hawley, A.; Vashi, A.; Nigro, J.; Werkmeister, J.A.; Ramshaw, J.A.M.
2011-01-01
We assessed the importance of glycosaminoglycans and sulfur-mediated bonds for the mechanical properties of lens capsules by comparing the stress-strain responses from control and treated pairs of bovine source. No significant change in mechanical properties was observed upon reduction of disulfide bonds. However, removal of glycosaminoglycan chains resulted in a significantly stiffer lens capsule, whereas high concentrations of reducing agent, which is expected to reduce the recently reported sulfilimine bond of collagen IV, resulted in a significantly less stiff lens capsule. A comparison of the diffraction patterns of the control and strongly reduced lens capsules indicated structural rearrangements on a nanometer scale. PMID:21539774
Wijeratne, Sithara S; Martinez, Jerahme R; Grindel, Brian J; Frey, Eric W; Li, Jingqiang; Wang, Liyun; Farach-Carson, Mary C; Kiang, Ching-Hwa
2016-03-01
Perlecan/HSPG2, a large, monomeric heparan sulfate proteoglycan (HSPG), is a key component of the lacunar canalicular system (LCS) of cortical bone, where it is part of the mechanosensing pericellular matrix (PCM) surrounding the osteocytic processes and serves as a tethering element that connects the osteocyte cell body to the bone matrix. Within the pericellular space surrounding the osteocyte cell body, perlecan can experience physiological fluid flow drag force and in that capacity function as a sensor to relay external stimuli to the osteocyte cell membrane. We previously showed that a reduction in perlecan secretion alters the PCM fiber composition and interferes with bone's response to a mechanical loading in vivo. To test our hypothesis that perlecan core protein can sustain tensile forces without unfolding under physiological loading conditions, atomic force microscopy (AFM) was used to capture images of perlecan monomers at nanoscale resolution and to perform single molecule force measurement (SMFMs). We found that the core protein of purified full-length human perlecan is of suitable size to span the pericellular space of the LCS, with a measured end-to-end length of 170±20 nm and a diameter of 2-4 nm. Force pulling revealed a strong protein core that can withstand over 100 pN of tension well over the drag forces that are estimated to be exerted on the individual osteocyte tethers. Data fitting with an extensible worm-like chain model showed that the perlecan protein core has a mean elastic constant of 890 pN and a corresponding Young's modulus of 71 MPa. We conclude that perlecan has physical properties that would allow it to act as a strong but elastic tether in the LCS. Copyright © 2015 International Society of Matrix Biology. Published by Elsevier B.V. All rights reserved.
Lei, Jiehua; Yuan, Yuqi; Lyu, Zhonglin; Wang, Mengmeng; Liu, Qi; Wang, Hongwei; Yuan, Lin; Chen, Hong
2017-08-30
Glycosaminoglycans (GAGs), especially heparin and heparan sulfate (HS), hold great potential for inducing the neural differentiation of embryonic stem cells (ESCs) and have brought new hope for the treatment of neurological diseases. However, the disadvantages of natural heparin/HS, such as difficulty in isolating them with a sufficient amount, highly heterogeneous structure, and the risk of immune responses, have limited their further therapeutic applications. Thus, there is a great demand for stable, controllable, and well-defined synthetic alternatives of heparin/HS with more effective biological functions. In this study, based upon a previously proposed unit-recombination strategy, several heparin-mimicking polymers were synthesized by integrating glucosamine-like 2-methacrylamido glucopyranose monomers (MAG) with three sulfonated units in different structural forms, and their effects on cell proliferation, the pluripotency, and the differentiation of ESCs were carefully studied. The results showed that all the copolymers had good cytocompatibility and displayed much better bioactivity in promoting the neural differentiation of ESCs as compared to natural heparin; copolymers with different sulfonated units exhibited different levels of promoting ability; among them, copolymer with 3-sulfopropyl acrylate (SPA) as a sulfonated unit was the most potent in promoting the neural differentiation of ESCs; the promoting effect is dependent on the molecular weight and concentration of P(MAG-co-SPA), with the highest levels occurring at the intermediate molecular weight and concentration. These results clearly demonstrated that the sulfonated unit in the copolymers played an important role in determining the promoting effect on ESCs' neural differentiation; SPA was identified as the most potent sulfonated unit for copolymer with the strongest promoting ability. The possible reason for sulfonated unit structure as a vital factor influencing the ability of the copolymers may be attributed to the difference in electrostatic and steric hindrance effect. The synthetic heparin-mimicking polymers obtained here can offer an effective alternative to heparin/HS and have great therapeutic potential for nervous system diseases.
Yin, Haifang; Boisguerin, Prisca; Moulton, Hong M; Betts, Corinne; Seow, Yiqi; Boutilier, Jordan; Wang, Qingsong; Walsh, Anthony; Lebleu, Bernard; Wood, Matthew Ja
2013-09-24
We have recently reported that cell-penetrating peptides (CPPs) and novel chimeric peptides containing CPP (referred as B peptide) and muscle-targeting peptide (referred as MSP) motifs significantly improve the systemic exon-skipping activity of morpholino phosphorodiamidate oligomers (PMOs) in dystrophin-deficient mdx mice. In the present study, the general mechanistic significance of the chimeric peptide configuration on the activity and tissue uptake of peptide conjugated PMOs in vivo was investigated. Four additional chimeric peptide-PMO conjugates including newly identified peptide 9 (B-9-PMO and 9-B-PMO) and control peptide 3 (B-3-PMO and 3-B-PMO) were tested in mdx mice. Immunohistochemical staining, RT-PCR and western blot results indicated that B-9-PMO induced significantly higher level of exon skipping and dystrophin restoration than its counterpart (9-B-PMO), further corroborating the notion that the activity of chimeric peptide-PMO conjugates is dependent on relative position of the tissue-targeting peptide motif within the chimeric peptide with respect to PMOs. Subsequent mechanistic studies showed that enhanced cellular uptake of B-MSP-PMO into muscle cells leads to increased exon-skipping activity in comparison with MSP-B-PMO. Surprisingly, further evidence showed that the uptake of chimeric peptide-PMO conjugates of both orientations (B-MSP-PMO and MSP-B-PMO) was ATP- and temperature-dependent and also partially mediated by heparan sulfate proteoglycans (HSPG), indicating that endocytosis is likely the main uptake pathway for both chimeric peptide-PMO conjugates. Collectively, our data demonstrate that peptide orientation in chimeric peptides is an important parameter that determines cellular uptake and activity when conjugated directly to oligonucleotides. These observations provide insight into the design of improved cell targeting compounds for future therapeutics studies.Molecular Therapy-Nucleic Acids (2013) 2, e124; doi:10.1038/mtna.2013.51; published online 24 September 2013.
van Wijk, Xander M.; Lawrence, Roger; Thijssen, Victor L.; van den Broek, Sebastiaan A.; Troost, Ran; van Scherpenzeel, Monique; Naidu, Natasha; Oosterhof, Arie; Griffioen, Arjan W.; Lefeber, Dirk J.; van Delft, Floris L.; van Kuppevelt, Toin H.
2015-01-01
Glycosaminoglycan (GAG) polysaccharides have been implicated in a variety of cellular processes, and alterations in their amount and structure have been associated with diseases such as cancer. In this study, we probed 11 sugar analogs for their capacity to interfere with GAG biosynthesis. One analog, with a modification not directly involved in the glycosidic bond formation, 6F-N-acetyl-d-galactosamine (GalNAc) (Ac3), was selected for further study on its metabolic and biologic effect. Treatment of human ovarian carcinoma cells with 50 μM 6F-GalNAc (Ac3) inhibited biosynthesis of GAGs (chondroitin/dermatan sulfate by ∼50–60%, heparan sulfate by ∼35%), N-acetyl-d-glucosamine (GlcNAc)/GalNAc containing glycans recognized by the lectins Datura stramonium and peanut agglutinin (by ∼74 and ∼43%, respectively), and O-GlcNAc protein modification. With respect to function, 6F-GalNAc (Ac3) treatment inhibited growth factor signaling and reduced in vivo angiogenesis by ∼33%. Although the analog was readily transformed in cells into the uridine 5′-diphosphate (UDP)-activated form, it was not incorporated into GAGs. Rather, it strongly reduced cellular UDP-GalNAc and UDP-GlcNAc pools. Together with data from the literature, these findings indicate that nucleotide sugar depletion without incorporation is a common mechanism of sugar analogs for inhibiting GAG/glycan biosynthesis.—Van Wijk, X. M., Lawrence, R., Thijssen, V. L., van den Broek, S. A., Troost, R., van Scherpenzeel, M., Naidu, N., Oosterhof, A., Griffioen, A. W., Lefeber, D. J., van Delft, F. L., van Kuppevelt, T. H. A common sugar-nucleotide-mediated mechanism of inhibition of (glycosamino)glycan biosynthesis, as evidenced by 6F-GalNAc (Ac3). PMID:25868729
NASA Astrophysics Data System (ADS)
Sandrock, Alfred W.; Matthew, William D.
1987-10-01
The effective regeneration of severed neuronal axons in the peripheral nerves of adult mammals may be explained by the presence of molecules in situ that promote the effective elongation of neurites. The absence of such molecules in the central nervous system of these animals may underlie the relative inability of axons to regenerate in this tissue after injury. In an effort to identify neurite growth-promoting molecules in tissues that support effective axonal regeneration, we have developed an in vitro bioassay that is sensitive to substrate-bound factors of peripheral nerve that influence the growth of neurites. In this assay, neonatal rat superior cervical ganglion explants are placed on longitudinal cryostat sections of fresh-frozen sciatic nerve, and the regrowing axons are visualized by catecholamine histofluorescence. Axons are found to regenerate effectively over sciatic nerve tissue sections. When ganglia are similarly explanted onto cryostat sections of adult rat central nervous system tissue, however, axonal regeneration is virtually absent. We have begun to identify the molecules in peripheral nerve that promote effective axonal regeneration by examining the effect of antibodies that interfere with the activity of previously described neurite growth-promoting factors. Axonal elongation over sciatic nerve tissue was found to be sensitive to the inhibitory effects of INO (for inhibitor of neurite outgrowth), a monoclonal antibody that recognizes and inhibits a neurite growth-promoting activity from PC-12 cell-conditioned medium. The INO antigen appears to be a molecular complex of laminin and heparan sulfate proteoglycan. In contrast, a rabbit antiserum that recognizes laminin purified from mouse Engelbreth-Holm-Swarm (EHS) sarcoma, stains the Schwann cell basal lamina of peripheral nerve, and inhibits neurite growth over purified laminin substrata has no detectable effect on the rate of axonal regeneration in our assay.
Yamamoto, Ayako; Uchiyama, Koji; Nara, Tomoka; Nishimura, Naomichi; Hayasaka, Michiko; Hanaoka, Kazunori; Yamamoto, Tatsuro
2014-01-01
Spock3/Testican-3 is a nervous system-expressed heparan sulfate proteoglycan belonging to a subgroup of the BM-40/SPARC/osteonectin family, the role of which in brain development is unclear. Because Spock1, a member of the Spock family, inhibits their attachment to substrates and the neurite outgrowth of cultured neuronal cells, Spock3 is also thought to be similarly involved in the neuronal development. In the present study, we established a Spock3-mutant mouse harboring a deletion extending from the presumptive upstream regulatory region to exon 4 of the Spock3 locus and performed histological and behavioral studies on these mutant mice. In wild-type (WT) mice, all Spock members were clearly expressed during brain development. In adults, intense Spock1 and Spock2 expressions were observed throughout the entire brain; whereas, Spock3 expression was no longer visible except in the thalamic nuclei. Thus, Spock3 expression is mostly confined to the developmental stage of the brain. In adult mutant mice, the cells of all cortical layers were swollen. The corpus callosum was narrowed around the central region along the rostral-caudal axis and many small spaces were observed without myelin sheaths throughout the entire corpus callosum. In addition, the cortical input and output fibers did not form into thick bundled fibers as well as the WT counterparts did. Moreover, a subpopulation of corticospinal axonal fibers penetrated into the dorsal striatum with moderately altered orientations. Consistent with these modifications of brain structures, the mutant mice exhibited decreased anxiety-like behavior and lowered sociability. Together, these results demonstrate that Spock3 plays an important role in the formation or maintenance of major neuronal structures in the brain. © 2014 S. Karger AG, Basel.
Chen, Hang; Gao, Zhihui; He, Changzheng; Xiang, Rong; van Kuppevelt, Toin H; Belting, Mattias; Zhang, Sihe
2016-05-01
Therapeutic macromolecules are internalized into the cell by either clathrin-mediated endocytosis (CME) or clathrin-independent endocytosis (CIE). Although some chaperone proteins play an essential role in CME (e.g. Hsc70 in clathrin uncoating), relatively few of these proteins are functionally involved in CIE. We previously revealed a role for the mitochondrial chaperone protein GRP75 in heparan sulfate proteoglycan (HSPG)-mediated, membrane raft-associated macromolecule endocytosis. However, the mechanism underlying this process remains unclear. In this study, using a mitochondrial signal peptide-directed protein trafficking expression strategy, we demonstrate that wild-type GRP75 expression enhanced the uptakes of HSPG and CIE marker cholera toxin B subunit but impaired the uptake of CME marker transferrin. The endocytosis regulation function of GRP75 is largely mediated by its subcellular location in mitochondria and is essentially determined by its ATPase domain. Interestingly, the mitochondrial expression of GRP75 or its ATPase domain significantly stimulates increases in both RhoA and Cdc42 activation, remarkably induces stress fibers and enhances filopodia formation, which collectively results in the promotion of CIE, but the inhibition of CME. Furthermore, silencing of Cdc42 or RhoA impaired the ability of GRP75 overexpression to increase CIE. Therefore, these results suggest that endocytosis vesicle enrichment of GRP75 by mitochondria trafficking upregulates CIE through an actin cytoskeleton reorganization mechanism mediated by the concurrent activation of Cdc42 and RhoA. This finding provides novel insight into organelle-derived chaperone signaling and the regulation of different endocytosis pathways in cells. Copyright © 2016 Elsevier Inc. All rights reserved.
Pal-Ghosh, Sonali; Tadvalkar, Gauri; Stepp, Mary Ann
2017-10-01
To determine the impact of the loss of syndecan 1 (SDC1) on intraepithelial corneal nerves (ICNs) during homeostasis, aging, and in response to 1.5-mm trephine and debridement injury. Whole-mount corneas are used to quantify ICN density and thickness over time after birth and in response to injury in SDC1-null and wild-type (WT) mice. High-resolution three-dimensional imaging is used to visualize intraepithelial nerve terminals (INTs), axon fragments, and lysosomes in corneal epithelial cells using antibodies against growth associated protein 43 (GAP43), βIII tubulin, and LAMP1. Quantitative PCR was performed to quantify expression of SDC1, SDC2, SDC3, and SDC4 in corneal epithelial mRNA. Phagocytosis was assessed by quantifying internalization of fluorescently labeled 1-μm latex beads. Intraepithelial corneal nerves innervate the corneas of SDC1-null mice more slowly. At 8 weeks, ICN density is less but thickness is greater. Apically projecting intraepithelial nerve terminals and lysosome-associated membrane glycoprotein 1 (LAMP1) are also reduced in unwounded SDC1-null corneas. Quantitative PCR and immunofluorescence studies show that SDC3 expression and localization are increased in SDC1-null ICNs. Wild-type and SDC1-null corneas lose ICN density and thickness as they age. Recovery of axon density and thickness after trephine but not debridement wounds is slower in SDC1-null corneas compared with WT. Experiments assessing phagocytosis show reduced bead internalization by SDC1-null epithelial cells. Syndecan-1 deficiency alters ICN morphology and homeostasis during aging, reduces epithelial phagocytosis, and impairs reinnervation after trephine but not debridement injury. These data provide insight into the mechanisms used by sensory nerves to reinnervate after injury.
Yamamoto, Shoshiro; Kato, Akari; Sakurai, Yu; Hada, Tomoya; Harashima, Hideyoshi
2017-04-10
The vascular endothelial growth factor (VEGF)-mediated enhancement in vascular permeability is considered to be a major factor in tumor-targeting delivery via the enhanced permeability and retention (EPR) effect. We previously reported that the silencing of the endothelial VEGF receptor (VEGFR2) by a liposomal siRNA system (RGD-MEND) resulted in an enhanced intratumoral distribution of polyethylene glycol (PEG)-modified liposomes (LPs) in a renal cell carcinoma, a type of hypervascularized cancer, although the inhibition of VEGF signaling would be expected to decrease the permeability of the tumor vasculature. We herein report that the enhancement in the intratumoral distribution of LPs by VEGFR2 inhibition was dependent on the vascular type of the tumor (stroma vessel type; SV and tumor vessel type; TV). In the case of TV-type tumors (renal cell carcinoma and hepatocellular carcinoma), inhibiting VEGFR2 improved intratumoral distribution, while no effect was found in the case of SV-type tumors (colorectal cancer). Moreover, through a comparison of the intratumoral distribution of LPs with a variety of physical properties (100nm vs 400nm, neutral vs negative vs positive), VEGFR2 inhibition was found to alter the tumor microenvironment, including heparan sulfate proteoglycans (HSPGs). In addition, the results regarding the effect of the size of nanoparticles indicated that VEGFR2 inhibition improved the penetration of nanoparticles through the vessel wall, but not via permeability, suggesting the involvement of an unknown mechanism. Our findings suggest that a combination of anti-angiogenic therapy and delivery via the EPR effect would be useful in certain cases, and that altering the tumor microenvironment by VEGFR2 blockade has a drastic effect on the intratumoral distribution of nanoparticles. Copyright © 2017 Elsevier B.V. All rights reserved.