To study the abnormal characteristics of chondrocyte differentiation and abnormal expression of collagen types in articular cartilage from patients with Kaschin kaschin-Beck disease (KBD).
The abnormal differentiation and expression of collagen types I, II, III, IV and X in articular cartilage from five cases of KBD patients were examined using monoclonal immunohistochemical methods.
(1) The expression of tyep II collagen was decreased in the upper zone in KBD articular cartilage. (2) The expression of types I, III and VI collagen were found throughout the articular cartilage, but type X collagen was located in the calcified cartilage zone and around chondrocyte clusters in the deep zone. (3) Chondrocyte clusters exhibited significant pericellular staining for types I, II, III and VI collagen, but did not stain with any collagen antibody in the chondronecrosis areas.
The abnormal collagen pattern in the articular cartilage of KBD patients was similar to that seen in primary osteoarthritic cartilage, but having more pronounced type I collagen expression in the surface zone and no collagen expression in the chondronecrosis areas.