Expression of intercellular adhesion molecule 1 (ICAM-1) on human articular cartilage chondrocytes.

Monoclonal antibodies have been used to demonstrate the induction of intercellular adhesion molecule 1 (ICAM-1) on chondrocytes in human articular cartilage. ICAM-1 was found not to be constitutively expressed but could be induced by exogenous interleukin 1 alpha(IL1- alpha) at concentrations ranging from 0.01 to 20 ng/ml during in vitro culture. Maximum expression was observed with 2-5ng/ml. In time-course experiments ICAM-1 was not expressed after 4h in culture with IL1 alpha. Expression was induced by 16h and was sustained for a minimum of 6 days in the continued presence of the cytokine. The endothelial leukocyte adhesion molecule (ELAM-1) was not expressed on chondrocytes and was not induced by IL1-alpha.