TIMP‐1 protein expression is stimulated by IL‐1β and IL‐6 in primary rat hepatocytes

Degradation of extracellular matrix proteins is performed by metalloproteinases which are inhibited by tissue inhibitors of metalloproteinases (TIMP). We expressed the murine TIMP-1 protein in E. coli and prepared a polyclonal antiserum against the recombinant protein. Using this antiserum we studied the biosynthesis and glycosylation of murine TIMP-1 protein in COS-7 cells transfected with a TIMP-1 expression plasmid by metabolic labeling and indirect immunofluorescence studies. In primary rat hepatocytes we show for the first time that TIMP-1 protein expression is up-regulated upon stimulation with IL-1 beta and IL-6. Since TIMP-1 is induced during the acute phase reaction it could possibly be involved in the pathogenesis of liver fibrosis.