LACK OF CHONDROITIN SULFATE EPITOPE IN THE PROLIFERATING ZONE OF THE GROWTH-PLATE OF CHICKEN TIBIA

Monoclonal antibodies specific to chondroitin sulphate (CS-56) and ker atan sulphate (AH12) were used to localize proteoglycans in the proxim al tibial articular cartilage and growth plate of broiler chickens. Th ere was no CS-56 labelling in the proliferative zone of the growth pla te. In contrast, intense labelling with this antibody was observed in the transitional and hypertrophic zones of the growth plate and the ar ticular cartilage. This was confirmed by extracting chondroitin sulpha te fractions from different zones of the growth plate and articular ca rtilage, and examining their antigenicities to CS-56 by ELISA inhibiti on assay. It was suggested that the maturation oo chondrocytes in the growth plate is related to the production of chondroitin sulphate with CS-56 epitope, which may be a prerequisite for normal endochondral bo ne formation in the chicken tibia. The role of chondroitin sulphate re cognized by CS-56 in the articular cartilage is unknown.