Antigens derived from citrullinated 14-3-3 and uses thereof in the diagnosis of rheumatoid arthritis

A method for diagnosing Rheumatoid Arthritis in a subject comprising:

• i) obtaining a biological sample from a subject suspected of having or at risk for developing Rheumatoid Arthritis,
• ii) contacting said biological sample from the subject with at least one citrullinated 14-3-3 eta protein or fragment thereof comprising at least one citrullinated 14-3-3 eta epitope under a condition suitable for the formation of at least one immune complex between the citrullinated 14-3-3 eta protein or fragment thereof and autoantibodies specific for said citrullinated 14-3-3 eta epitope that may be present in the biological sample, wherein said citrullinated 14-3-3 eta epitope comprises a citrulline residue at a position selected from the group consisting of position 4, position 12, position 19, position 42, position 61, position 86 and position 227 of SEQ ID NO:
• 5;
• and
• iii) detecting the presence of immune complexes between the citrullinated 14-3-3 eta protein or fragment thereof and autoantibodies that specifically bind the citrullinated 14-3-3 eta epitope of the citrullinated 14-3-3 eta protein or fragment thereof, wherein said presence of said immune complexes is indicative of Rheumatoid Arthritis in said subject.