Independent induction of interleukin 6 and prostaglandin E2 by interleukin 1 in human articular chondrocytes.

Interleukin 6 is a cytokine with growth and differentiation activities on a number of cell types. Human articular chondrocytes produce interleukin 6 and this production appears to be constitutive but can be stimulated in a dose-dependent manner by interleukin 1. Other stimulators of interleukin 6 production in chondrocytes include tumour necrosis factor-alpha, polyriboinosinic: polyribocytidylic acid and bacterial lipopolysaccharide. Interleukin 6 production is not inhibited by prostaglandin E2 but may be partially dependent on prostaglandin E2 production. Using an antiserum to interleukin 6 we have demonstrated that the production of prostaglandin E2 under basal conditions and in response to interleukin 1 is probably not mediated by interleukin 6.