Natural human IL-1 beta exhibits regulatory actions on human bone-derived cells in vitro.

We have shown that natural homogenous IL-1 beta exhibits regulatory activities on human bone-derived osteoblast-like cells in vitro. IL-1 beta stimulated cellular proliferation and the synthesis of prostaglandin E2 and plasminogen activator activity by the cultured human osteoblast-like cells. In contrast to these stimulatory actions, IL-1 beta antagonised the stimulatory effects of 1.25(OH)2 D3 on the production of alkaline phosphatase and osteocalcin, two markers of the osteoblast phenotype. These studies indicate that this cytokine may therefore have potential physiological and pathological effects on bone metabolism.