A new hepatocyte stimulating factor: cardiotrophin-1 (CT-1)

Abstract Recently, a novel cytokine, cardiotrophin-1 (CT-1), was cloned and found to induce cardiac myocyte hypertrophy in vitro. Amino acid sequence similarity showed CT-1 to be a member of the IL-6/LIF/CNTF/OSM/IL-11 cytokine family. Since all known members of the IL-6 cytokine family induce an hepatic acute phase protein (APP) gene expression, we investigated the ability of CT-1 to induce a liver acute phase response. Upon stimulation of rat hepatoma cells, CT-1 and LIF induced the strongest rat fibrinogen mRNA expression, OSM and IL-6 induced a less pronounced response. When human hepatoma cells and primary rat hepatocytes were stimulated with CT-1, the expression of human haptoglobin a…