Idiopathic chondrolysis--an immunopathologic study.

Investigations were performed to determine the potential of an immunologically-mediated basis underlying development of severe bilateral knee chondrolysis arising over a 2-yr period in a 29-yr-old man. Humoral and cell-mediated immune responses to autologous and homologous articular cartilage proteoglycan and collagen rich fractions were identified in sequential studies. Employing gradient derived peripheral blood mononuclear cells there was demonstration of spontaneous, T cell mitogen augmented and autologous cartilage antigen-induced release of factors capable of degrading articular cartilage proteoglycans and inhibiting chondrocyte glycosaminoglycan synthesis. Evidence has thus been provided incriminating immunologic events, likely functioning in a perpetuant manner, in the pathogenesis of this chondrolytic process.