MONONUCLEAR PHAGOCYTES OF ACUTELY INJURED RAT-LIVER ABUNDANTLY SYNTHESIZE AND SECRETE FIBRONECTIN IN CONTRAST TO KUPFFER CELLS OF NORMAL LIVER

Fibronectin (FN) is a multifunctional glycoprotein involved in wound healing. It is early deposited after liver injury in necrotic areas. The cellular source of this FN remained undetermined. For this reason, mononuclerar phagocytes (MNP) of normal and acutely CCl4-injured rat liver were isolated, characterized immunocytochemically and kept in culture. Synthesis of FN was studied by biosynthetic labelling, immunoprecipitation, and SDS-PAGE and on RNA level by Northern blotting and hybridization with 32-P-labeled, FN-specific cDNAs. In contrast to normal Liver, MNP of acutely injured livers synthesized and secreted FN in abundant amounts. Synthesis was higher in small than in large MNP and higher in MNP isolated 36h after the injury (vs 60h) and decreased during the time in culture. MNP could be an important cellular source of FN deposited in the early stage of liver injury. (C) 1995 Academic Press, Inc.