Anti-lubricin monoclonal antibodies created using lubricin-knockout mice immunodetect lubricin in several species and in patients with healthy and diseased joints.

The epitope motif is repeated is present about 20 times in the lubricin protein sequence. The epitope-specific mAbs were used to detect lubricin in synovial fluid, plasma and serum of patients with rheumatoid arthritis or osteoarthritis by western blot and by competition ELISA.