Test Details: This test looks for CCP (cyclic citrullinated peptide) antibodies in the blood. Autoantibodies can cause disease by attacking the healthy cells of the body. CCP antibodies target healthy tissues in the joints. Rheumatoid arthritis is a progressive, autoimmune disease that causes pain, swelling, and stiffness in the joints. CCP antibodies are found in more than 75 percent of people who have Rheumatoid arthritis (RA). This test is also helpful in differentiating RA from other inflammatory arthritis or connective tissue diseases.