TYRP1 and rheumatoid arthritis: Besides for the potent Cat-B inhibition in vitro, this series of m-PFMKs were effective in reducing inflammation and degradation of articular cartilage and bone in an ex vivo model of adjuvant-induced arthritis, as it is well-known that rheumatoid arthritis is associated with high levels of Cat-B in the synovial joints [17].