Levels of circulating MDL-1-expressing monocytes, mRNA expression levels of MDL-1 and DAP12 on PBMCs, and levels of serum proinflammatory cytokines in patients with active rheumatoid arthritis (RA), patients with inactive RA, patients with osteoarthritis (OA) and healthy controls (HC). Here, TYROBP is linked to rheumatoid arthritis.