Inflammatory cytokines induce synthesis and secretion of gro protein and a neutrophil chemotactic factor but not β2-microglobulin in human synovial cells and fibroblasts

Abstract

Exposure of human synovial cells and fibroblasts in monolayer culture to interleukin 1 results in prominent secretion of proteins with M(r) values of 6000 and 7000. By N-terminal sequence analysis, the M(r)-6000 protein is identified as the protein encoded by a recently described gro mRNA. The M(r)-7000 protein is identical to a neutrophil chemotactic factor released from monocytes. Stimulation of normal human fibroblasts with tumour necrosis factor α also results in expression and secretion of these two proteins. In addition to these cytokine-induced proteins, we have identified β2-microglobulin as an M(r)-8000 protein constitutively secreted by synovial cells.