Changes in the serum levels of several proteins have been observed in RA patients: cytokines such as IL-1α, IL1-β, IL-6, IL-10, and TNF-α are increased in RA compared to normal (Deane et al., 2010; Milman et al., 2010); and intercellular adhesion molecule-1 (ICAM-1) level is increased in juvenile RA compared to normal (Bloom et al., 2005; Ishikawa et al., 2009). Here, IL1B is linked to rheumatoid arthritis.