The present invention provides, in part, an antibody display system that simultaneously uses a secretion and a display mode. A bait complexed with a monovalent antibody fragment can be expressed on the surface of the host cell wherein the fragment may be assayed for antigen binding while full antibody is simultaneously secreted from the host cell. Methods of using the system for identifying antibodies that bind specifically to an antigen of interest are also provided. Polypeptides, polynucleotides and host cells useful for making the antibody display system are also provided along with methods of use thereof.

A method for evaluating the progression of hepatic fibrosis in non-alcoholic steatohepatitis, said method comprising measuring the amount of a sugar chain having a structure represented by formula (I) and/or a precursor sugar chain of the biosynthesis of a sugar chain having a structure represented by formula (I) in a sample.

Disclosed are compositions and methods related to the use of sialoglycan as markers for the diagnosis and prognosis of cancers and inflammatory conditions. In one aspect, also disclosed herein are engineered probes and chimeric probes with differential binding ability to sialoglycans.

The present disclosure provides methods, compositions, and kits for the rapid release, labeling, and detection of O-glycans present on a glycoconjugate, such as a glycoprotein, glycopeptide, peptidoglycan, or proteoglycan of interest. The compositions and methods allow the released O-glycans to be subjected to high-throughput analysis.

The present invention provides a set of novel isobaric chemical tags, also referred herein as SUGAR (Isobaric Multiplex Reagents for Carbonyl Containing Compound). These labeling tags are compact and easy to synthesize at high yield and purity in just a few steps using commercially available starting materials. The tagging reagents of the present invention comprise: a) a reporter group, having at least one atom that is optionally isotopically labeled; b) a balancing group, also having at least one atom that is optionally isotopically labeled, and c) an aldehyde, ketone, or carboxylic acid reactive group. The multiplex SUGAR tags are able to react with an aldehyde, ketone, or carboxylic acid group of the molecule to be tagged, which offers the capability for labeling and quantitation of glycans, proteins/peptides, and fatty acids.

Disclosed is a novel means for accurate qualitative and quantitative analyses for each N-glycosylation site. The method of analyzing N-linked sugar chain(s) of glycoprotein according to the present invention comprises: treating a part of a glycopeptide-containing sample to be analyzed with endo-β-N-acetylglucosaminidases to cleave off sugar chains while leaving one GlcNAc of the chitobiose core on the Asn at the N-glycosylation site; subjecting the obtained sugar chain-cleaved sample to preliminary liquid chromatography/mass spectrometry; predicting the retention time of the glycopeptide of interest and the mass-to-charge ratio (m/z) of the precursor ion in main analysis based on the results of the preliminary liquid chromatography/mass spectrometry; and carrying out the main analysis. By this method, the binding sites and structures of N-linked sugar chains in a glycoprotein can be analyzed. By using the sugar chain-cleaved sample as an internal standard in the main analysis, quantitative analysis of sugar chains at each glycosylation site also becomes possible.

A mass spectrometry method includes detecting, in a first mass spectrometry of a sample containing a glycan having a plurality of sialic acids each modified differently, a plurality of oxonium ions derived from each of the plurality of sialic acids, and calculating relative values of intensities of the plurality of oxonium ions based on data obtained by the detection.

Provided is a glycated protein assay reagent containing at least a Trinder reagent, 4-aminoantipyrine, protease, a stabilizer of the protease, and ferrocyanide, wherein at least the Trinder reagent is contained in a Trinder reagent-containing partial composition, at least the 4-aminoantipyrine is contained in a 4-aminoantipyrine-containing partial composition, the stabilizer of the protease is a stabilizer that increases the oxidation-reduction potential of the ferrocyanide above 0.058 V when the stabilizer of the protease and the ferrocyanide are mixed, and the oxidation-reduction potential is an oxidation-reduction potential in a reaction system containing the stabilizer of the protease and the ferrocyanide and not containing glycated protein.

The present invention provides a set of novel isobaric chemical tags, also referred herein as SUGAR (Isobaric Multiplex Reagents for Carbonyl Containing Compound). These labeling tags are compact and easy to synthesize at high yield and purity in just a few steps using commercially available starting materials. The tagging reagents of the present invention comprise: a) a reporter group, having at least one atom that is optionally isotopically labeled; b) a balancing group, also having at least one atom that is optionally isotopically labeled, and c) an aldehyde, ketone, or carboxylic acid reactive group. The multiplex SUGAR tags are able to react with an aldehyde, ketone, or carboxylic acid group of the molecule to be tagged, which offers the capability for labeling and quantitation of glycans, proteins/peptides, and fatty acids.

The invention relates to methods for the diagnosis of ischemia or ischemic tissue damage, methods for predicting the progression of ischemia in a patient having suffered an ischemic event, for determining the prognosis of a patient having suffered an ischemic event and for determining the risk that a patient suffering from stable coronary disease suffers a recurrent ischemic event based on the detection of the levels of glycosylated Apo J. The invention relates as well to a method for the determination of glycosylated Apo J in a sample.