PIVKA-II measurement method, measurement reagent, and measurement kit

Patent metadata

Field	Value
Publication number	US-10539559-B2
Application number	US-201314420122-A
Country	US
Kind code	B2
Filing date	Aug 6, 2013
Priority date	Aug 9, 2012
Publication date	Jan 21, 2020
Grant date	Jan 21, 2020

Abstract

Disclosed are a PIVKA-II measurement method that achieves better serum-plasma correlation than conventional methods, and a reagent and a kit therefor. The PIVKA-II measurement method according to the present invention comprises measuring PIVKA-II in a sample by an immunoassay using a mixture of an anti-F1 antibody that specifically binds to prothrombin fragment F1 or an antigen-binding fragment thereof and an anti-F2 antibody that specifically binds to prothrombin fragment F2 or an antigen-binding fragment thereof; and an anti-PIVKA-II antibody that specifically binds to PIVKA-II or an antigen-binding fragment thereof.

First claim

The invention claimed is:

1. A method for measuring Protein Induced by Vitamin K Absence or Antagonist-II (PIVKA-II), comprising:
measuring PIVKA-II in a sample by carrying out an immunoassay using antibodies comprising (a) an anti-PIVKA-II antibody that specifically binds to PIVKA-II or an antigen-binding fragment thereof and (b) a mixture of (i) an anti-F1 antibody that specifically binds to prothrombin fragment 1 or an antigen-binding fragment thereof and (ii) an anti-F2 antibody that specifically binds to prothrombin fragment 2 or an antigen-binding fragment thereof,
wherein said anti-F1 antibody, said anti-F2 antibody, and said anti-PIVKA-II antibody are monoclonal antibodies,
wherein the mixture of the anti-F1 antibody and the anti-F2 antibody is in a mixing ratio of 1:0.2-2,
wherein the immunoassay is a sandwich immunoassay using said mixture as a labeled antibody and said anti-PIVKA-II antibody as an immobilized antibody, or using said mixture as an immobilized antibody and said anti-PIVKA-II antibody as the labeled antibody, and
wherein said sample is serum or plasma.

2. The method according to claim 1 , wherein said anti-F1 antibody is an antibody that recognizes an epitope in the F1 region and binds to PIVKA-II, and said anti-F2 antibody is an antibody that recognizes an epitope in the F2 region and binds to PIVKA-II.

3. The method according to claim 1 , wherein said immunoassay is carried out by a sandwich method using said mixture as a labeled antibody and said anti-PIVKA-II antibody or antigen-binding fragment thereof as an immobilized antibody.

4. The method according to claim 1 , wherein the mixture ratio between said anti-F1 antibody or the antigen-binding fragment thereof and said anti-F2 antibody or the antigen-binding fragment thereof is a weight ratio of 1:0.5-1.0.

5. The method according to claim 1 , wherein said immunoassay has a serum-plasma ratio of 95% to 113%.

6. The method according to claim 1 , wherein the mixture of the anti-F1 antibody and the anti-F2 antibody is in a mixing ratio of 1:0.2-0.5.

Assignees

• Fujirebio Kk
• Sekisui Medical Co Ltd

Inventors

• Yamaguchi Kentaro
• Aoyagi Katsumi
• Terao Azusa

Classifications

• G01N33/86 Primary

  involving blood coagulating time {or factors, or their receptors} · CPC title

• C07K14/745

  Blood coagulation or fibrinolysis factors · CPC title

• G01N33/57525

  of the liver or pancreas · CPC title

• G01N33/54306 Primary

  Solid-phase reaction mechanisms · CPC title

• G01N2333/745

  Assays involving non-enzymic blood coagulation factors · CPC title