Figure 4.

Immunohistochemical analysis of cartilage oligomeric matrix protein (COMP)-specific mAbs binding to joint cartilage in vivo. COMP specific-mAbs were purified, biotinylated and injected into neonatal COMP^+/+ mice (100 μg of antibody in 100 μl of PBS/mice) and limbs were collected after 24 h. Seven μm cryo-sections were stained with DAB using extravidin-peroxidase as the detection system. Anti-CII monoclonal antibody (M2139)-injected animals served as positive controls, anti-COMP mAb injected COMP^-/- mice were used as negative controls. Positive mAb binding to joint surfaces is marked by arrows.