The present invention pertains to methods for characterizing proteins in a sample using native capillary electrophoresis-mass spectrometry. The present invention pertains to methods for detecting and/or discriminating between post-translational modification variants of an antibody of interest in a sample, detecting and/or discriminating between antibodies in an antibody mixture, and characterizing monospecific antibody side products in a bispecific antibody sample.

The purpose of the present invention is to provide: a liver-type fatty acid-binding protein standard by which, in a measurement using a specifically binding substance, the range of variation of a measured value caused by a liver-type fatty acid-binding protein can be narrowed; a method of evaluating the standard; a method of drawing a calibration curve of a liver-type fatty acid-binding protein; and a method of quantifying the protein. A liver-type fatty acid-binding protein standard in which a coefficient of change in oxidation, said coefficient being represented by the ratio of a measured value obtained by using a liver-type fatty acid-binding protein standard having been subjected to an oxidation treatment with 10 mM of an oxidant for 1 hour at 25 C. to a measured value obtained by using the liver-type fatty acid-binding protein standard not subjected to the oxidation treatment, is set to 1.4 or less; a liver-type fatty acid-binding protein to be used in the standard; a DNA encoding the protein; a cell transformed by the DNA; a method of producing the protein; a method of evaluating the standard; a method of regulating the variation range of a measured value in a measurement using the standard; a method of drawing a calibration curve for the protein; and a method of quantifying the protein.

One aspect of the present invention describes materials and methods of quantitatively measuring the density or percent occupancy of DNA binding proteins such as histones, histone variants, histone post translational modifications and transcription factors in chromatin at given DNA loci. One embodiment measures a factor's average quantity at specific gene loci, and controls for a number of pitfalls concerning antibody quality and handling issues. Other embodiments include calibrating and quantifying chromatin immunoprecipitation assays, assessing an affinity reagent specificity, as well as required reagents and their formulation in kits. Another embodiment allows for the diagnosis of a condition or disease by measuring the density of a histone modification at a genomic locus.

A reagent composition for releasing vitamin D compounds bound to vitamin D-binding protein, an in vitro method for the detection of a vitamin D compound in which the vitamin D compound is released from vitamin D-binding protein by the use of this reagent composition and the reagent mixture obtained in this manner. The use of the disclosed reagent composition to release vitamin D compounds as well as a kit for detecting a vitamin D compound which contains the reagent composition for releasing vitamin D compounds in addition to common detecting reagents.

The present invention relates to a combination comprising an aminothiolester compound or a pharmaceutically acceptable salt thereof, in particular the S-methyl 4-(dimethylamino)-4-methylpent-2-ynethioate or a pharmaceutically acceptable salt thereof, and more particularly the 4-(Dimethylamino)-4-methyl-2-pentynethioic acid S-methyl ester fumarate, and a compound able to increase H.sub.2O.sub.2 level in cancer cells of a subject, in particular for use for the treatment of cancer in a subject, wherein cancer cells of said subject do not overproduce H.sub.2O.sub.2 in comparison to a control value and have a level of GSH below 5 nmol for 25000 cells.

Provided is a method for analyzing a protein-containing sample. The method comprises (1) dissolving a probe capable of non-specifically interacting with a plurality of proteins in a plurality of solvents having different ionic strengths and/or pH levels; (2) adding a protein-containing sample to a plurality of probe solutions prepared in the step (1), thereby the proteins in the sample and the probe are interacted non-specifically; (3) measuring the fluorescence intensities of the plurality of probe solutions to which the protein-containing sample was added in the step (2); and (4) comparing the pattern of fluorescence intensities obtained in the step (3) with the pattern of fluorescence intensities obtained from a reference sample.

This disclosure relates to methods of determining the amount of post translational modification (PTM) associated with one or more tau peptide fragments of a tau protein in a sample, and methods of evaluating a subject for having a tauopathy, the methods comprising, in part, determining the amount of post translational modification (PTM) associated with one or more tau peptide fragments of a tau protein in a sample, and comparing the amount of the tau PTMs associated with one or more tau peptide fragments with one or more reference levels for the tau peptide fragments, thereby determining whether a subject has a tauopathy.

Compositions and methods for identifying glucuronylated protein drug products are provided.

Methods of predicting an in vivo serum concentration of an antibody with a post-translational modification of interest after administration of the antibody are provided, as are methods for predicting a subject's exposure to post-translational variants of the antibody. The methods include predicting a percentage of the antibody with the post-translational modification of interest using an in vivo rate constant determined for the post-translational modification, and multiplying the predicted percentage of the antibody with the post-translational modification of interest by the in vivo concentration of the antibody to determine the concentration of the antibody with the post-translational modification of interest.

The description relates to a method and kits for determining the total carbonylation level on a polypeptide.