Predicting Arthritis

Scientists from the Kennedy Institute of Rheumatology at the Oxford University have reported that a simple blood test could predict the onset of rheumatoid arthritis (RA), sixteen years before it contracts a person. The blood test finds out antibodies that attack a protein called tenascin–C.

When inflammation occurs in the body, some proteins are altered in a process called citrullination. These altered proteins can prompt an immune response, in which the antibodies work against the body causing RA. Currently, the test that spots antibodies to citrullinated proteins is used to diagnose RA. The test, however, has a low diagnostic sensitivity but a more general test called CCP, which detects synthetic citrullinated peptides, identifies a lot more RA cases.

Tenascin–C is found in high levels in the joints of people suffering from RA. Therefore, scientists decided to see whether it could be citrullinated and if so, whether it was a target for antibodies that attack the body in RA. When scientists looked for antibodies in more than 2,000 patients, they diagnosed RA in around 50 percent cases. This list includes those cases that were previously not diagnosed by CCP.