Methods disclosed herein include an improved technique for comparing a glycosylation profile of a first protein (e.g., an innovator protein drug) with a glycosylation profile of a second protein (e.g., a corresponding biogeneric/biosimilar). For example, a method of manufacture can include providing or obtaining a batch of a test glycoprotein drug substance, using mass spectrometry to acquire a test oxonium ion profile from a sample of the test glycoprotein drug substance batch, comparing the test oxonium ion profile to a corresponding target oxonium ion profile of a target glycoprotein drug product, and processing the batch of the test glycoprotein drug substance as a drug product if the difference between the test oxonium ion profile and the corresponding target oxonium ion profile is tolerable, or taking an alternative action if the difference between the test oxonium ion profile and the target oxonium ion profile is not tolerable.

It is intended to provide a method and an immunochromatographic device, which are capable of measurement with sufficient sensitivity by performing a nitrous acid extraction treatment over a sufficient period of time in an immunochromatography method of extracting and measuring a sugar chain antigen by nitrous acid extraction on an immunochromatographic test piece. The present invention provides an immunochromatographic device comprising an immunochromatographic test piece for extracting and measuring a sugar chain antigen in a specimen, and a container which stores the test piece, the immunochromatographic device having a specimen addition port in a sample pad of the test piece, the immunochromatographic test piece comprising: a sample pad to which a specimen mixed with nitrite or an acid solution is added; a label region comprising a labeled antibody obtained by labeling an antibody against the sugar chain antigen; and a detection region on which the antibody against the sugar chain antigen is immobilized, wherein an antibody-sugar chain antigen-labeled antibody complex is formed in the detection region to measure the sugar chain antigen, and the immunochromatographic test piece having a region impregnated with a neutralizing reagent upstream of the label region, and further having a region impregnated with a solid acid reagent when the specimen mixed with the nitrite is used, or a region impregnated with nitrite when the specimen mixed with the acid solution is used, upstream of the region impregnated with the neutralizing reagent, wherein the immunochromatographic device (i) has a wide specimen addition port for promoting the extraction of the sugar chain antigen with the nitrite and the solid acid reagent by retaining an added specimen sample solution and supplying the specimen sample solution in a short time to the region impregnated with the solid acid reagent or the nitrite, and (ii) has no space between the addition port and the sample pad so as to prevent the sample from escaping from the addition port.

Methods of assessing biosimilarity of proteins, e.g., therapeutic antibodies, are described.

Lung cancer can be detected by measuring sites in pancreatic ribonuclease 1 (also abbreviated as “RNase 1”), wherein each of the sites is a site capable of being modified with an N-linked sugar chain. Lung cancer is detected by measuring items A and B as mentioned below and then comparing the ratio of the value of A to the value of B: A=the amount of sites in pancreatic ribonuclease 1, wherein the sites are sites each capable of being modified with an N-linked sugar chain and each having an N-linked sugar chain bound thereto or each having an N-linked sugar chain unbound thereto; and B=the amount of sites in pancreatic ribonuclease 1, wherein the sites are sites each capable of being modified with an N-linked sugar chain.

The invention provides a method of diagnosing arthritis or other joint degrading disease in a subject which comprises determining whether there is a presence or increase of lubricin having a joint tissue posttranslational modification, in a blood sample from the subject, the presence or increase of the lubricin having the joint tissue posttranslational modification indicating arthritis or other joint degrading disease in the subject. The invention further provides a kit or protocol for detecting arthritis or other joint degrading disease by detecting lubricin, the lubricin comprising a joint tissue posttranslational modification.

Glycoproteins having particular sialylation patterns, and methods of making and using such glycoproteins, are described.

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.

Provided is a method of obtaining an index value used for pathological tissue diagnosis of prostate cancer, which method has low invasiveness and can be performed at a low cost. The method is a method of estimating a Gleason score that represents the malignancy of prostate cancer, which method includes: measuring the content of a prostate-specific antigen having an N-acetylgalactosamine residue at a non-reducing terminal of a sugar chain in a sample; and estimating that the Gleason score is 7 or higher when the thus measured value is larger than a threshold value, or estimating that the Gleason score is 6 or lower when the measured value is smaller than a threshold value. The prostate-specific antigen is preferably quantified by a method including the step of binding a molecule having an affinity for β-N-acetylgalactosamine residue, such as Wisteria floribunda lectin, soybean agglutinin, Vicia Villosa lectin or an anti-β-N-acetylgalactosamine antibody, to the prostate-specific antigen.

Provided is a test method for identifying prostate cancer by analyzing a sugar chain modifying PSA in a specimen, and detecting an abundance of a multisialylated LacdiNAc structure, in particular Glycan ID: 7512, Glycan ID: 7603, Glycan ID: 7612, and/or Glycan ID: 7613. Furthermore, calculation of PSA G-index from relative abundance(s) of Glycan ID: 7512 and/or Glycan ID: 7603 enables detection of prostate cancer with good specificity even in a patient having a PSA value in a gray zone.

A measurement method includes a measurement step of measuring a first single value and a second signal value, the first signal value being based on a reaction between a first reacting substance and the sample, the second signal value being based on a reaction between a second reacting substance and the sample, the first reacting substance having a higher reactivity to a second detection target than to a first detection target, the second reacting substance having a higher reactivity to the first detection target than to the second detection target.