Elevation of S2-bound α1-acid glycoprotein is associated with chronic hepatitis C virus infection and hepatocellular carcinoma.

There is an urgent need for new high-quality markers for the early detection of hepatocellular carcinoma (HCC). Åström et al. suggested that S2-bound α1-acid glycoprotein (AGP) might be a promising marker.

Determination of Fucose Concentration in a Lectin-Based Displacement Microfluidic Assay.

We compare three different methods to quantify the monosaccharide fucose in solutions using the displacement of a large glycoprotein, lactoferrin. Two microfluidic analysis methods, namely fluorescence detection of (labeled) lactoferrin as it is displaced by unlabeled fucose and the displacement of (unlabeled) lactoferrin in SPR, provide fast responses and continuous data during the experiment, theoretically providing significant information regarding the interaction kinetics between the saccharide groups and binding sites. For comparison, we also performed a static displacement ELISA.

Reverse lectin ELISA for detecting fucosylated forms of α1-acid glycoprotein associated with hepatocellular carcinoma.

Altered fucosylation of glycoproteins is associated with development of hepatocellular carcinoma (HCC). Lectins have been commonly used to assay changes in fucosylation of plasma glycoproteins. In the present study a recombinantly engineered form of the fucose binding lectin Aleuria aurantia (AAL) consisting of a single binding site for fucose (S2), was used to construct a reverse lectin ELISA method.

Fucoidan-Mimetic Glycopolymers as Tools for Studying Molecular and Cellular Responses in Human Blood Platelets.

The marine sulfated polysaccharide fucoidan displays superior ability to induce platelet aggregation compared to other sulfated polysaccharides. As such, it is an attractive tool for studying molecular and cellular responses in activated platelets. The heterogeneous structure, however, poses a problem in such applications.

Synthesis and anticancer properties of fucoidan-mimetic glycopolymer coated gold nanoparticles.

Gold nanoparticles coated with fucoidan-mimetic glycopolymers were synthesized that displayed good colloidal stability and promising anti-cancer properties. Fucoidan mimetic glycopolymers on their own were nontoxic, while glycopolymer coated gold nanoparticles displayed selective cytotoxicity to human colon cancer cell lines (HCT116) while it was non-toxic to mouse fibroblast cells (NIH3T3).

Synthesis and biological evaluation of fucoidan-mimetic glycopolymers through cyanoxyl-mediated free-radical polymerization.

The sulfated marine polysaccharide fucoidan has been reported to have health benefits ranging from antivirus and anticancer properties to modulation of high blood pressure. Hence, they could enhance the biological function of materials for biomedical applications. However, the incorporation of fucoidan into biomaterials has been difficult, possibly due to its complex structure and lack of suitable functional groups for covalent anchoring to biomaterials.

Disialo-trisialo bridging of transferrin is due to increased branching and fucosylation of the carbohydrate moiety.

Background: Carbohydrate deficient transferrin (CDT) is used for detection of alcohol abuse and follow-up. High performance liquid chromatography (HPLC) of transferrin glycoforms is highly specific for identification of alcohol abuse, but unresolved disialo- and trisialotransferrin glycoforms sometimes makes interpretation difficult. The cause of this phenomenon is unknown, cannot be explained by genetic variants of transferrin, but seems to be associated with liver disease.

Elucidating the selectivity of recombinant forms of Aleuria aurantia lectin using weak affinity chromatography.

Aberrant glycosylation is connected to several pathological conditions and lectins are useful tools to characterize glycosylated biomarkers. The Aleuria aurantia lectin (AAL) is of special interest since it interacts with all types of fucosylated saccharides. AAL has been expressed in Escherichia coli as a fully functional recombinant protein.

New treatment for IgA nephropathy: enteric budesonide targeted to the ileocecal region ameliorates proteinuria.

Background: Systemic corticosteroid treatment has been shown to exert some protection against renal deterioration in IgA nephropathy (IgAN) but is not commonly recommended for long-term use due to the well-known systemic side effects. In this study, we investigated the efficacy and safety of a new enteric formulation of the locally acting glucocorticoid budesonide (Nefecon®), designed to release the active compound in the ileocecal region. The primary objective was to evaluate the efficacy of targeted release budesonide on albuminuria.

Production and characterization of a monomeric form and a single-site form of Aleuria aurantia lectin.

Lectins have widely been used in structural and functional studies of complex carbohydrates. They usually bind carbohydrates with relatively low affinity, but compensate for this by multivalency. This multivalent nature of lectins can sometimes produce unwanted reactions such as agglutination or precipitation of target glycoproteins, when using them in different biological and analytical assays.

alpha(1)-acid glycoprotein (AGP)-induced platelet shape change involves the Rho/Rho kinase signalling pathway.

alpha(1)-acid glycoprotein (AGP) is an acute-phase protein that contributes to inflammation processes. The role of AGP in platelet activation and thrombosis is, however, largely unknown. Therefore, we thoroughly investigated the effects of AGP on human platelets.

Sialic acid residues play a pivotal role in alpha(1)-acid glycoprotein (AGP)-induced generation of reactive oxygen species in chemotactic peptide pre-activated neutrophil granulocytes.

Objective: We have recently shown that terminal sialic acid residues are essential for alpha(1)-acid glycoprotein (AGP)-induced Ca(2+) mobilization in neutrophils. The aim of the present study was to establish the importance of sialic acid residues on AGP in modulating human neutrophil functions, with emphasis on the generation of reactive oxygen species (ROS).

Materials And Methods: ROS were measured by luminol-enhanced chemiluminescence in isolated human neutrophils.

Effects of alpha1-acid glycoprotein fucosylation on its Ca2+ mobilizing capacity in neutrophils.

We recently showed that the acute-phase protein alpha(1)-acid glycoprotein (AGP) induces rises in cytosolic calcium concentration, [Ca(2+)](i,) in neutrophils through sialic acid dependent interactions with the neutrophil receptors siglec-5 and/or siglec-14. Whereas both siglec-5 and siglec-14 have a relatively broad specificity for sialylated oligosaccharide structures, including both structures with terminal alpha2-3 or alpha2-6 linked sialic acid, there is a markedly reduced affinity to the fucosylated epitope sialyl Lewis x (SLe(x)). Increased fucosylation, leading to increased expression of SLe(x) on AGP is commonly associated with inflammatory conditions.

Detection of a high affinity binding site in recombinant Aleuria aurantia lectin.

Lectins are carbohydrate binding proteins that are involved in many recognition events at molecular and cellular levels. Lectin-oligosaccharide interactions are generally considered to be of weak affinity, however some mushroom lectins have unusually high binding affinity towards oligosaccharides with K (d) values in the micromolar range. This would make mushroom lectins ideal candidates to study protein-carbohydrate interactions.

The acute-phase protein alpha 1-acid glycoprotein (AGP) induces rises in cytosolic Ca2+ in neutrophil granulocytes via sialic acid binding immunoglobulin-like lectins (siglecs).

We studied whether the acute-phase protein alpha1-acid glycoprotein (AGP) induces rises in [Ca2+]i in neutrophils and sought to identify the corresponding AGP receptor (or receptors). We found that AGP elicited a minimal rise in [Ca2+]i in Fura-2-loaded neutrophils, and this response was markedly enhanced by pretreatment with anti-L-selectin antibodies. (The EC50 value of the AGP-induced Ca2+ response was 9 microg/ml.

Characterization of EBV-transformed B-cells established from an individual homozygously mutated (G329A) in the FUT7 alpha1,3-fucosyltransferase gene.

The alpha1,3-fucosyltransferase VII (Fuc-TVII) is involved in the biosynthesis of E- and P-selectin ligands such as sialyl Lewis x (SLe(x)) on human leukocytes. Recently, individuals were characterized carrying a missense mutation (G329A; Arg110-Gln) in the FUT7 gene encoding this enzyme. The mutated FUT7 construct produced a Fuc-TVII enzyme with impaired activity compared with the wildtype enzyme.

HPLC analysis of carbohydrate deficient transferrin isoforms isolated by the Axis-Shield %CDT method.

Background: Carbohydrate-deficient transferrin (CDT) is elevated during prolonged overconsumption of alcohol and CDT is considered to be the most specific biochemical marker for alcohol overconsumption. However, an accurate method for analysing CDT is necessary because the test is frequently used for example in legal matters.

Methods: Patient serum samples were analysed with the Axis-Shield %CDT and eluates were pooled together.

Lectin affinity capillary electrophoresis in glycoform analysis applying the partial filling technique.

The study of protein glycosylation and its significance in biological interactions is a field of growing interest. This work demonstrates a lectin-based separation of protein glycoforms of alpha1-acid glycoprotein (AGP or orosomucoid) with capillary electrophoresis. Glycoform analysis was performed with a "partial filling technique" with the lectin Concanavalin A (Con A) as affinity ligand.

Diagnostic accuracy of alpha(1)-acid glycoprotein fucosylation for liver cirrhosis in patients undergoing hepatic biopsy.

Background: Increased fucosylation of serum glycoproteins has previously been reported in patients with liver disease. We analyzed alpha(1)-acid glycoprotein (AGP) fucosylation in serum samples from patients investigated for suspected liver disease to evaluate its value as a biochemical marker for liver cirrhosis.

Methods: We used a novel lectin immunoassay adapted to the AutoDELFIA system to analyze AGP fucosylation in 261 consecutive patients admitted for liver biopsy at Malmö University Hospital in Southern Sweden.

Polymorphonuclear leukocytes from individuals carrying the G329A mutation in the alpha 1,3-fucosyltransferase VII gene (FUT7) roll on E- and P-selectins.

We recently identified several individuals carrying a missense mutation (G329A; Arg(110)-Gln) in the FUT7 gene encoding fucosyltransferase VII. This enzyme is involved in the biosynthesis of the sialyl Lewis x (Le(x)) epitope on human leukocytes, which has been identified as an important component of leukocyte ligands for E- and P-selectin. No enzyme activity was measurable in expression studies in COS-7 cells using the mutated FUT7 construct.

Analysis of glycoproteins in cell culture supernatants using a lectin immunosensor technique.

A method based on a surface plasmon resonance technique for detection of changes in concentration and glycosylation of proteins in cell culture supernatant is described. The method was used to analyze alpha(1)-acid glycoprotein (AGP) produced by a human hepatoma cell line (HepG2). Cell culture supernatant was injected to a BIACORE 2000 instrument and AGP was captured on the sensor chip by immobilized antibodies.

Fucosylation of alpha1-acid glycoprotein (orosomucoid) compared with traditional biochemical markers of inflammation in recent onset rheumatoid arthritis.

Background: Fucosylation of alpha1-acid glycoprotein (AGP, orosomucoid) has previously been found to be increased in patients with rheumatoid arthritis. Furthermore, the degree of fucosylation has been suggested to reflect disease activity. Therefore, we investigated the fucosylation of AGP in 131 patients (96 women and 35 men) with recent onset rheumatoid arthritis (RA).

Characterization of galactosyl glycerolipids in the HT29 human colon carcinoma cell line.

Glycoglycerolipids constitute a family of glycolipids with apparently very restricted expression in human tissues. They have previously been detected only in the testis and the nervous system. In the present study, two glycoglycerolipids were isolated from the HT29 human colon carcinoma cell line.