Patent ID: 9347941
Filing Date: 2016-05-24
CPC Classification: G01N

Claim Text:
1. An antigen detecting method for diagnosing rheumatoid arthritis, comprising (1) treating a biological sample of a human subject suspected of having rheumatoid arthritis with a first antibody binding specifically to an autoantigen of rheumatoid arthritis to form an antigen-antibody complex between the first antibody and an autoantigen of rheumatoid arthritis present in the sample; and (2) detecting a citrullinated autoantigen by treating the antigen-antibody complex with a second antibody comprising a heavy chain variable region having an amino acid sequence of SEQ ID NO: 3 and a light chain variable region having an amino acid sequence of SEQ ID NO: 4, or an antigen-binding fragment thereof; (3) measuring a level of the citrullinated antigen-antibody complex formation to diagnose rheumatoid arthritis, wherein the biological sample in step (1) is a tissue, a cell, whole blood, plasma, blood serum, blood, saliva, synovial fluid, urine, sputum, lymph fluid, or intercellular fluid, and wherein the autoantigen of rheumatoid arthritis in the step (1) is selected from the group consisting of filaggrin, fibrin, fibrinogen, vimentin, collagen and alpha-enolase.