Structural characterization of glycosaminoglycans from zebrafish in different ages

Zebrafish-based platform for emerging bio-contaminants and virus inactivation research

Emerging bio-contaminants such as viruses have affected health and environment settings of every country. Viruses are the minuscule entities resulting in severe contagious diseases like SARS, MERS, Ebola, and avian influenza. Recent epidemic like the SARS-CoV-2, the virus has undergone mutations strengthen them and allowing to escape from the remedies. Comprehensive knowledge of viruses is essential for the development of targeted therapeutic and vaccination treatments. Animal models mimicking human biology like non-human primates, rats, mice, and rabbits offer competitive advantage to assess risk of viral infections, chemical toxins, nanoparticles, and microbes. However, their economic maintenance has always been an issue. Furthermore, the redundancy of experimental results due to aforementioned aspects is also in examine. Hence, exploration for the alternative animal models is crucial for risk assessments. The current review examines zebrafish traits and explores the possibilities to monitor emerging bio-contaminants. Additionally, a comprehensive picture of the bio contaminant and virus particle invasion and abatement mechanisms in zebrafish and human cells is presented. Moreover, a zebrafish model to investigate the emerging viruses such as coronaviridae and poxviridae has been suggested.

Characterization of disease-specific chondroitin sulfate nonreducing end accumulation in mucopolysaccharidosis IVA

Morquio syndrome type A, also known as MPS IVA, is a rare autosomal recessive disorder caused by deficiency of N-acetylgalactosamine-6-sulfatase, a lysosomal hydrolase critical in the degradation of keratan sulfate (KS) and chondroitin sulfate (CS). The CS that accumulates in MPS IVA patients has a disease-specific nonreducing end (NRE) terminating with N-acetyl-D-galactosamine 6-sulfate, which can be specifically quantified after enzymatic depolymerization of CS polysaccharide chains. The abundance of N-acetyl-D-galactosamine 6-sulfate over other possible NRE structures is diagnostic for MPS IVA. Here, we describe an assay for the liberation and measurement of N-acetyl-D-galactosamine 6-sulfate and explore its application to MPS IVA patient samples in pilot studies examining disease detection, effects of age and treatment with enzyme-replacement therapy. This assay complements the existing urinary KS assay by quantifying CS-derived substrates, which represent a distinct biochemical aspect of MPS IVA. A more complete understanding of the disease could help to more definitively detect disease across age ranges and more completely measure the pharmacodynamic efficacy of therapies. Larger studies will be needed to clarify the potential value of this CS-derived substrate to manage disease in MPS IVA patients.

Characterization of Glycosaminoglycans in Gaping and Intact Connective Tissues of Farmed Atlantic Salmon (Salmo salar) Fillets by Mass Spectrometry

In the Atlantic salmon (Salmo salar) aquaculture industry, gaping (the separation of muscle bundles from the connective tissue) is a major quality problem. This study characterized chondroitin sulfate (CS) and heparan sulfate (HS) in the connective tissue of intact and gaping salmon fillets from 30 salmon by mass spectrometry. Statistical difference was detected between gaping and intact tissues only when comparing pairwise samples from the same individual (n = 10). The gaping tissue had a lower content of monosulfated CS disaccharides (p = 0.027), and the relative distribution of CS disaccharides was significantly different (p < 0.05). The HS chains were short (average = 14.09, SD = 4.91), and the intact tissue seemed to have a more uniform HS chain structure compared to the gaping tissue. Time-series samples from the same individuals are recommended for future research to improve the understanding of reasons and implications of these differences.

Heparan Sulfate as a Therapeutic Target in Tauopathies: Insights From Zebrafish

Microtubule-associated protein tau (MAPT) hyperphosphorylation and aggregation, are two hallmarks of a family of neurodegenerative disorders collectively referred to as tauopathies. In many tauopathies, including Alzheimer's disease (AD), progressive supranuclear palsy (PSP) and Pick's disease, tau aggregates are found associated with highly sulfated polysaccharides known as heparan sulfates (HSs). In AD, amyloid beta (Aβ) peptide aggregates associated with HS are also characteristic of disease. Heparin, an HS analog, promotes misfolding, hyperphosphorylation and aggregation of tau protein in vitro. HS also provides cell surface receptors for attachment and uptake of tau seeds, enabling their propagation. These findings point to HS-tau interactions as potential therapeutic targets in tauopathies. The zebrafish genome contains genes paralogous to MAPT, genes orthologous to HS biosynthetic and chain modifier enzymes, and other genes implicated in AD. The nervous system in the zebrafish bears anatomical and chemical similarities to that in humans. These homologies, together with numerous technical advantages, make zebrafish a valuable model for investigating basic mechanisms in tauopathies and identifying therapeutic targets. Here, we comprehensively review current knowledge on the role of HSs in tau pathology and HS-targeting therapeutic approaches. We also discuss novel insights from zebrafish suggesting a role for HS 3-O-sulfated motifs in tau pathology and establishing HS antagonists as potential preventive agents or therapies for tauopathies.

Viscera of fishes as raw material for extraction of glycosaminoglycans of pharmacological interest

World fisheries and aquaculture production totaled 167 million tons in 2014. This high fish production generates a lot of waste that could be used as raw material for extraction of substances of pharmacological interest. In this work, we extract and characterize glycosaminoglycans (GAGs) present in the viscera of Nile tilapia (Oreochromis niloticus) and Pacu (Piaractus mesopotamicus), which are among the most vastly produced fishes in inland aquaculture in Brazil. Moreover, the anticoagulant activity of the GAGs fractions was evaluated. GAGs were obtained from total defatted viscera, after proteolysis, precipitation with ethanol, anion exchange chromatography and treatment with chondroitinase. Chondroitin sulfate (CS), dermatan sulfate (DS) and heparan sulfate (HS) were identified by agarose gel electrophoresis and NMR analyses. CS, DS and HS were identified in equivalent fractions obtained from both fishes, and all GAGs fractions showed anticoagulant activity.

Established method of chondroitin sulphate extraction from buffalo (Bubalus bubalis) cartilages and its identification by FTIR

A study was conducted for extraction of chondroitin sulphate (CS) from buffalo tracheal, nasal and joint cartilages. CS was extracted from cartilages using 0.25% papain digestion, dialyzed, precipitated with 10% TCA and finally lyophilized to dry powder. Dimethylmethylene blue assay was performed to estimate the quantity of CS extracted. Identification of extracted CS was performed with SDS-PAGE and Fourier transforms infrared spectroscopy (FTIR). SDS-PAGE analysis of extracted CS revealed similar electrophoretic pattern to that of standard and the molecular weight ranged from 5 to 20 kDa. FTIR spectra of extracted CS revealed presence of characteristic peaks of –CONH vibration of amide group, coupling of C–O stretching vibration, S=O stretching vibrations and –C–O–S molecules confirms the CS moiety. It can be concluded that extraction method adopted could efficiently be utilized for the extraction of CS from buffalo by-products like tracheal, nasal and joint cartilages.

Disaccharide analysis of chondroitin and heparin from farmed Atlantic salmon

The heparin disaccharides detected in farmed Atlantic salmon (Salmo salar) gills and intestines have, with one exception, been reported in porcine heparin. The relative amounts of disaccharides appear to be very different in the two species. Two chondroitin disaccharides with a proposed essential role in the zebrafish (Danio rerio) development and differentiation are detected in farmed Atlantic salmon. In addition, most of the chondroitin/dermatan sulfate and heparin disaccharides detected here have been reported in zebrafish, in support of the claims of the heparin presence in fish. The same chondroitin/dermatan disaccharides were detected in the bones of bony fishes. The rare disaccharide UA2S-GalNAc that was found in trace amounts in all 5 bony fishes was found in relative high amounts in gills and in significant amounts in intestines. The rare heparin disaccharide UA2S-GlcN was in relative highest amounts both in gills and intestines. In context with our previous reports, this communication suggests that glycosaminoglycans in farmed Atlantic salmon heparin need further studies in order to clarify structure and function.

Effects of C-xylopyranoside derivative on epithelial regeneration in an in vitro 3D oral mucosa model

Identifying substandard tissue-engineered oral mucosa grafts with a poor epithelium before clinical use is critical to ensure quality assurance/control in regenerative medicine, leading to success of grafting. This study investigated the effects of one of the C-xylopyranoside derivatives, β-D-xylopyranoside-n-propane-2-one (XPP), on oral epithelial regeneration. Using a three-dimensional oral mucosa model, we analyzed changes of the epithelial structure, glycosaminoglycan (GAG) synthesis, the expression levels of basement membrane zone markers, and substrates of Akt/mTOR signaling. Compared with the control, 2 mM XPP treatment increased the mean and minimal epithelial thickness, and reduced the variation of epithelial thickness. It also stimulated expressions of decorin and syndecan-1 with change of GAG amount and/or composition, and enhanced the expressions of integrin α6, CD44, and Akt/mTOR signaling substrates. These findings suggest that XPP supplementation contributes to consistent epithelial regeneration. Moreover, upregulation of those markers may play a role in increasing the quality of the oral mucosal epithelium.

Isolation and structural characterization of glycosaminoglycans from heads of red salmon (Oncorhynchus nerka)

Glycosaminoglycans (GAGs) are linear, highly negatively charged polysaccharides. They are ubiquitous molecules exhibiting a wide range of biological functions with numerous applications in pharmaceutical, cosmetic, and nutraceutical industrials. The commercial fish-processing industry generates large quantities of solid waste, which can represent a potential resource for GAG production. In this study, we used a three-step recovery and purification scheme for isolation of GAGs from the heads of red salmon (Oncorhynchus nerka). The GAGs recovery yield was 6 to 7 mg from 1 gram of salmon head powder. The recovered GAGs were structurally analyzed with polyacrylamide gel electrophoresis and by disaccharide composition analysis with reversed-phase ion-pair high-performance liquid chromatography. The analyses showed the major composition of the GAGs in red salmon head were chondroitin sulfate C and E.

Comprehensive analysis of herpes simplex virus 1 (HSV-1) entry mediated by zebrafish 3-O-Sulfotransferase isoforms: implications for the development of a zebrafish model of HSV-1 infection

Binding of herpes simplex virus 1 (HSV-1) envelope glycoprotein D (gD) to the receptor 3-O-sulfated heparan sulfate (3-OS HS) mediates viral entry. 3-O-Sulfation of HS is catalyzed by the 3-O-sulfotransferase (3-OST) enzyme. Multiple isoforms of 3-OST are differentially expressed in tissues of zebrafish (ZF) embryos. Here, we performed a comprehensive analysis of the role of ZF 3-OST isoforms (3-OST-1, 3-OST-5, 3-OST-6, and 3-OST-7) in HSV-1 entry. We found that a group of 3-OST gene family isoforms (3-OST-2, -3, -4, and -6) with conserved catalytic and substrate-binding residues of the enzyme mediates HSV-1 entry and spread, while the other group (3-OST-1, -5, and -7) lacks these properties. These results demonstrate that HSV-1 entry can be recapitulated by certain ZF 3-OST enzymes, a significant step toward the establishment of a ZF model of HSV-1 infection and tissue-specific tropism.

Zebrafish 3-O-sulfotransferase-4 generated heparan sulfate mediates HSV-1 entry and spread

Rare modification of heparan sulfate (HS) by glucosaminyl 3-O sulfotransferase (3-OST) isforms generates an entry receptor for herpes simplex virus type-1 (HSV-1). In the zebrafish (ZF) model multiple 3-OST isoforms are differentially expressed. One such isoform is 3-OST-4 which is widely expressed in the central nervous system of ZF. In this report we characterize the role of ZF encoded 3-OST-4 isoform for HSV-1 entry. Expression of ZF 3-OST-4 into resistant Chinese hamster ovary (CHO-K1) cells promoted susceptibility to HSV-1 infection. This entry was 3-O sulfated HS (3-OS HS) dependent as pre-treatment of ZF 3-OST-4 cells with enzyme HS lyases (heparinase II/III) significantly reduced HSV-1 entry. Interestingly, co-expression of ZF 3-OST-4 along with ZF 3-OST-2 which is also expressed in brain rendered cells more susceptible to HSV-1 than 3-OST-4 alone. The role of ZF-3-OST-4 in the spread of HSV-1 was also evaluated as CHO-K1 cells that expressed HSV-1 glycoproteins fused with ZF 3-OST-4 expressing effector CHO-K1 cells. Finally, adding further evidence ZF 3-OST-4 mediated HSV-1 entry was inhibited by anti-3O HS G2 peptide. Taken together our results demonstrate a role for ZF 3-OST-4 in HSV-1 pathogenesis and support the use of ZF as a model to study it.

Zebrafish: modeling for herpes simplex virus infections

For many years, zebrafish have been the prototypical model for studies in developmental biology. In recent years, zebrafish has emerged as a powerful model system to study infectious diseases, including viral infections. Experiments conducted with herpes simplex virus type-1 in adult zebrafish or in embryo models are encouraging as they establish proof of concept with viral-host tropism and possible screening of antiviral compounds. In addition, the presence of human homologs of viral entry receptors in zebrafish such as 3-O sulfated heparan sulfate, nectins, and tumor necrosis factor receptor superfamily member 14-like receptor bring strong rationale for virologists to test their in vivo significance in viral entry in a zebrafish model and compare the structure-function basis of virus zebrafish receptor interaction for viral entry. On the other end, a zebrafish model is already being used for studying inflammation and angiogenesis, with or without genetic manipulations, and therefore can be exploited to study viral infection-associated pathologies. The major advantage with zebrafish is low cost, easy breeding and maintenance, rapid lifecycle, and a transparent nature, which allows visualizing dissemination of fluorescently labeled virus infection in real time either at a localized region or the whole body. Further, the availability of multiple transgenic lines that express fluorescently tagged immune cells for in vivo imaging of virus infected animals is extremely attractive. In addition, a fully developed immune system and potential for receptor-specific knockouts further advocate the use of zebrafish as a new tool to study viral infections. In this review, we focus on expanding the potential of zebrafish model system in understanding human infectious diseases and future benefits.

Spinal deformity in aged zebrafish is accompanied by degenerative changes to their vertebrae that resemble osteoarthritis

Age-related degenerative changes within the vertebral column are a significant cause of morbidity with considerable socio-economic impact worldwide. An improved understanding of these changes through the development of experimental models may lead to improvements in existing clinical treatment options. The zebrafish is a well-established model for the study of skeletogenesis with significant potential in gerontological research. With advancing age, zebrafish frequently develop gross deformities of their vertebral column, previously ascribed to reduced trunk muscle tone. In this study, we assess degenerative changes specifically within the bone and cartilage of the vertebral column of zebrafish at 1, 2 and 3-years of age. We show increased frequency and severity of spinal deformities/curvatures with age. Underlying the most severe phenotypes are partial or complete vertebral dislocations and focal thickening of the vertebral bone at the joint margins. MicroCT examination demonstrates small defects, fractures and morphological evidence suggestive of bone erosion and remodeling (i.e. osteophytes) within the vertebrae during aging, but no significant change in bone density. Light and electron microscopic examination reveal striking age-related changes in cell morphology, suggestive of chondroptosis, and tissue remodelling of the vertebral cartilage, particularly within the pericellular micro-environment. Glycosaminoglycan analysis of the vertebral column by HPLC demonstrates a consistent, age-related increase in the yield of total chondroitin sulfate disaccharide, but no change in sulfation pattern, supported by immunohistochemical analysis. Immunohistochemistry strongly identifies all three chondroitin/dermatan sulphate isoforms (C-0-S, C-4-S/DS and C-6-S) within the vertebral cartilage, particularly within the pericellular micro-environment. In contrast, keratan sulfate immunolocalises specifically with the notochordal tissue of the intervertebral disc, and its labelling diminishes with age. In summary, these observations raise the prospect that zebrafish, in addition to modelling skeletal development, may have utility in modelling age-related degenerative changes that affect the skeleton during senescence.

Expression of glycosaminoglycan epitopes during zebrafish skeletogenesis

BACKGROUND

The zebrafish is an important developmental model. Surprisingly, there are few studies that describe the glycosaminoglycan composition of its extracellular matrix during skeletogenesis. Glycosaminoglycans on proteoglycans contribute to the material properties of musculo skeletal connective tissues, and are important in regulating signalling events during morphogenesis. Sulfation motifs within the chain structure of glycosaminoglycans on cell-associated and extracellular matrix proteoglycans allow them to bind and regulate the sequestration/presentation of bioactive signalling molecules important in musculo-skeletal development.

RESULTS

We describe the spatio-temporal expression of different glycosaminoglycan moieties during zebrafish skeletogenesis with antibodies recognising (1) native sulfation motifs within chondroitin and keratan sulfate chains, and (2) enzyme-generated neoepitope sequences within the chain structure of chondroitin sulfate (i.e., 0-, 4-, and 6-sulfated isoforms) and heparan sulfate glycosaminoglycans. We show that all the glycosaminoglycan moieties investigated are expressed within the developing skeletal tissues of larval zebrafish. However, subtle changes in their patterns of spatio-temporal expression over the period examined suggest that their expression is tightly and dynamically controlled during development.

CONCLUSIONS

The subtle differences observed in the domains of expression between different glycosaminoglycan moieties suggest differences in their functional roles during establishment of the primitive analogues of the skeleton.

Role of Filopodia in HSV-1 Entry into Zebrafish 3-O-Sulfotransferase-3-Expressing Cells

Background:

Heparan sulfate proteoglycans (HSPGs) modified by zebrafish (ZF) encoded glucosaminyl 3-O sulfotransferase-3 (3-OST-3) generate a receptor for herpes simplex virus type-1 (HSV-1) entry and spread. In order to elucidate the mechanism by which HSV-1 enters into ZF-3-OST-3 cells, we investigated the mode of viral entry.

Results:

Under high resolution scanning electron microscopy (SEM), actin cytoskeleton changes were observed by a dramatic increase in the number of filopodia formed during early interactions of HSV-1 with the target cells. While the increase in number was common among all the infected cells, the highest numbers of filopodia was observed in cells expressing the 3-OST-3 modified form of heparan sulfate (HS) encoded either by human or ZF. The levels of viral infection and filopodia induction were reduced with the actin polymerization inhibitors, Cytochalasin-D and Lantriculin B, suggesting an important role for actin reorganization during ZF-3-OST-3 mediated HSV-1 entry. Supporting an interesting possibility of filopodia usage during HSV-1 spread, pre-treatment of cytochalasin D in ZF-3-OST-3 cells drastically reduced virus glycoprotein induced cell fusion.

Conclusions:

Taken together, our results provide new evidence on the involvement of filopodia during HSV-1 infection of ZF-3-OST-3 cells and confirm a role for modified heparan sulfate in cytoskeleton rearrangement during HSV-1 entry.

Zebrafish encoded 3-O-sulfotransferase-2 generated heparan sulfate serves as a receptor during HSV-1 entry and spread

Previously we reported the role of zebrafish (ZF) encoded glucosaminyl 3-O-sulfotransferase-3 (3-OST-3) isoform in assisting herpes simplex virus type-1 (HSV-1) entry and spread by generating an entry receptor to HSV-1 envelope glycoprotein D (gD). However, the ability of ZF encoded 3-OST-2 isoform to participate in HSV-1 entry has not been determined although it is predominantly expressed in ZF brain, a prime target for HSV-1 to infect and establish lifelong latency. Here we report the expression cloning of ZF encoded 3-OST-2 isoform and demonstrate HSV-1 entry into resistant Chinese hamster ovary (CHO-K1) cells expressing the clone. Additional significance of ZF encoded 3-OST-2 receptor was demonstrated using medically important isolates of HSV-1. In addition, interference to HSV-1 entry was observed upon co-expression of HSV-1 gD and ZF 3-OST-2. Similarly HSV-1 entry was significantly inhibited by the pre-treatment of cells with enzyme HS lyases (heparinase II/III). Finally, ZF-3-OST-2 expressing CHO-K1 was able to fuse with HSV-1 glycoprotein expressing cells suggesting their role in HSV-1 spread. Taken together our result demonstrates a role for ZF 3-OST-2 in HSV-1 pathogenesis.

"Casting" light on the role of glycosylation during embryonic development: insights from zebrafish

Zebrafish (Danio rerio) remains a versatile model organism for the investigation of early development and organogenesis, and has emerged as a valuable platform for drug discovery and toxicity evaluation [1-6]. Harnessing the genetic power and experimental accessibility of this system, three decades of research have identified key genes and pathways that control the development of multiple organ systems and tissues, including the heart, kidney, and craniofacial cartilage, as well as the hematopoietic, vascular, and central and peripheral nervous systems [7-31]. In addition to their application in large mutagenic screens, zebrafish has been used to model a variety of diseases such as diabetes, polycystic kidney disease, muscular dystrophy and cancer [32-36]. As this work continues to intersect with cellular pathways and processes such as lipid metabolism, glycosylation and vesicle trafficking, investigators are often faced with the challenge of determining the degree to which these pathways are functionally conserved in zebrafish. While they share a high degree of genetic homology with mouse and human, the manner in which cellular pathways are regulated in zebrafish during early development, and the differences in the organ physiology, warrant consideration before functional studies can be effectively interpreted and compared with other vertebrate systems. This point is particularly relevant for glycosylation since an understanding of the glycan diversity and the mechanisms that control glycan biosynthesis during zebrafish embryogenesis (as in many organisms) is still developing.Nonetheless, a growing number of studies in zebrafish have begun to cast light on the functional roles of specific classes of glycans during organ and tissue development. While many of the initial efforts involved characterizing identified mutants in a number of glycosylation pathways, the use of reverse genetic approaches to directly model glycosylation-related disorders is now increasingly popular. In this review, the glycomics of zebrafish and the developmental expression of their glycans will be briefly summarized along with recent chemical biology approaches to visualize certain classes of glycans within developing embryos. Work regarding the role of protein-bound glycans and glycosaminoglycans (GAG) in zebrafish development and organogenesis will also be highlighted. Lastly, future opportunities and challenges in the expanding field of zebrafish glycobiology are discussed.

Evolution of glycosaminoglycans: Comparative biochemical study

Glycosaminoglycans, a major component of the extracellular matrix molecules in animal tissues, play important roles in various physiological events. Glycosaminoglycans are found in not only vertebrates but also many invertebrates, implying a conserved function in the animal kingdom. Here, we discuss the analysis of glycosaminoglycans in 11 invertebrate phyla focusing on structure as well as physiological functions elucidated in model organisms. Various sulfated structures of heparan sulfate are widely distributed from very primitive organisms to humans, indicating an involvement in fundamental biological processes. By contrast, chondroitin/dermatan sulfate from lower organisms is limited in its structural complexity and often associated with a particular function. The presence of hyaluronic acid outside of vertebrates has been reported only in a mollusk.

Heparin mapping using heparin lyases and the generation of a novel low molecular weight heparin

Seven pharmaceutical heparins were investigated by oligosaccharide mapping by digestion with heparin lyase 1, 2, or 3, followed by high performance liquid chromatography analysis. The structure of one of the prepared mapping standards, ΔUA-Gal-Gal-Xyl-O-CH(2)CONHCH(2)COOH (where ΔUA is 4-deoxy-α-l-threo-hex-4-eno-pyranosyluronic acid, Gal is β-d-galactpyranose, and Xyl is β-d-xylopyranose) released from the linkage region using either heparin lyase 2 or heparin lyase 3 digestion, is reported for the first time. A size-dependent susceptibility of site cleaved by heparin lyase 3 was also observed. Heparin lyase 3 acts on the undersulfated domains of the heparin chain and does not cleave the linkages within heparin's antithrombin III binding site. Thus, a novel low molecular weight heparin (LMWH) is afforded on heparin lyase 3 digestion of heparin due to this unique substrate specificity, which has anticoagulant activity comparable to that of currently available LMWH.

Analysis of glycosaminoglycans in stem cell glycomics

Glycosaminoglycans (GAGs) play a critical role in the binding and activation of growth factors in cell signal transduction required for biological development. A glycomics approach can be used to examine GAG content, composition, and structure in stem cells in order to characterize their general differentiation. Specifically, this method may be used to evaluate chondrogenic differentiations by profiling for the GAG content of the differentiated cells. Here, embryonic-like teratocarcinoma cells, NCCIT, a developmentally pluripotent cell line, were used as a model for establishing GAG glycomic methods, but will be easily transferrable to embryonic stem cell cultures.

Hyphenated techniques for the analysis of heparin and heparan sulfate

The elucidation of the structure of glycosaminoglycan has proven to be challenging for analytical chemists. Molecules of glycosaminoglycan have a high negative charge and are polydisperse and microheterogeneous, thus requiring the application of multiple analytical techniques and methods. Heparin and heparan sulfate are the most structurally complex of the glycosaminoglycans and are widely distributed in nature. They play critical roles in physiological and pathophysiological processes through their interaction with heparin-binding proteins. Moreover, heparin and low-molecular weight heparin are currently used as pharmaceutical drugs to control blood coagulation. In 2008, the health crisis resulting from the contamination of pharmaceutical heparin led to considerable attention regarding their analysis and structural characterization. Modern analytical techniques, including high-performance liquid chromatography, capillary electrophoresis, mass spectrometry, and nuclear magnetic resonance spectroscopy, played critical roles in this effort. A successful combination of separation and spectral techniques will clearly provide a critical advantage in the future analysis of heparin and heparan sulfate. This review focuses on recent efforts to develop hyphenated techniques for the analysis of heparin and heparan sulfate.

Glycosaminoglycan characterization by electrospray ionization mass spectrometry including fourier transform mass spectrometry

Electrospray ionization mass spectrometry (ESI MS) is a versatile analytical technique in glycomics of glycosaminoglycans (GAGs). Combined with enzymology, ESI MS is used for assessing changes in disaccharide composition of GAGs biosynthesized under different environmental or physiological conditions. ESI coupled with high-resolution mass analyzers such as a Fourier transform mass spectrometer (FTMS) permits accurate mass measurement of large oligosaccharides and intact GAGs as well as structural characterization of GAG oligosaccharides using information-rich fragmentation methods such as electron detachment dissociation. The first part of this chapter describes methods for disaccharide compositional profiling using ESI MS and the second part is dedicated to FTMS and tandem MS methods of GAG compositional and structural analysis.

Proteoglycomics: recent progress and future challenges

Proteoglycomics is a systematic study of structure, expression, and function of proteoglycans, a posttranslationally modified subset of a proteome. Although relying on the established technologies of proteomics and glycomics, proteoglycomics research requires unique approaches for elucidating structure-function relationships of both proteoglycan components, glycosaminoglycan chain, and core protein. This review discusses our current understanding of structure and function of proteoglycans, major players in the development, normal physiology, and disease. A brief outline of the proteoglycomic sample preparation and analysis is provided along with examples of several recent proteoglycomic studies. Unique challenges in the characterization of glycosaminoglycan component of proteoglycans are discussed, with emphasis on the many analytical tools used and the types of information they provide.

Zebrafish-encoded 3-O-sulfotransferase-3 isoform mediates herpes simplex virus type 1 entry and spread

Heparan sulfate proteoglycans modified by human glucosaminyl 3-O-sulfotransferase-3 (3-OST-3) isoform generates the cellular receptor for herpes simplex virus type 1 (HSV-1). Interestingly, the ability of zebrafish (ZF)-encoded 3-OST-3 isoform to modify heparan sulfate to mediate HSV-1 entry and cell-cell fusion has not been determined although it is predominantly expressed in ZF, a popular model organism to study viral infections. Here, we demonstrate that expression of ZF-encoded 3-OST-3 isoform renders the resistant Chinese hamster ovary (CHO-K1) cells to become susceptible for HSV-1 entry. The following lines of evidence support the important role of ZF-encoded 3-OST-3 isoform as the mediator of HSV-1 entry into CHO-K1 cells: (1) ZF 3-OST-3-expressing CHO-K1 cells were able to preferentially bind HSV-1 glycoprotein D, and (2) CHO-K1 cells expressing ZF-encoded 3-OST-3 acquire the ability to fuse with cells expressing HSV-1 glycoproteins. Finally, knocking down 3-OST-3 receptor by siRNA in ZF fibroblasts cells significantly reduced HSV-1 entry and glycoprotein D binding to cells. Taken together, our results provide novel insight into the significance of ZF 3-OST-3 isoform as an HSV-1 entry and fusion receptor and its potential involvement in the HSV-1 disease model of ZF.