Figure 1.

The role of neutrophils in the early as well as late stages of osteoarthritis progression. Neutrophils are recruited at the synovial capsule and contribute to the secretion of many cytokines and chemokines within synovial fluid that promote inflammation and vascular infiltration and inhibit chondrogenic progenitor cell migration. The formation of neutrophil elastase (NE) enhances cartilage degradation, chondrocytes apoptosis, unbalanced subchondral bone remodeling, and osteophyte formation.