Biosynthesis of interstitial types of collagen by albumin-producing rat liver parenchymal cell (hepatocyte) clones in culture

Abstract

Collagenous components produced by an albumin-producing rat liver parenchymal cell clone (BB) in culture were analyzed. The cells secreted 90% of the [3H]proline-labeled collagenous components into the medium after 18 h incubation in vitro. Analysis of the components by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and by CM cellulose chromatography of cyanogen bromide peptides after separation of individual collagen chains showed that the cells produced type I, type I trimer and type III collagens in the ratio 59:29:4. These components account for 90% of the collagen isolated. Type I and type I trimer collagens were present in the medium and cell layer fractions, but type III collagen was found solely in the medium. The cells produced other minor collagenous components, one of which was similar to type V collagen. Analysis of collagen components produced by another liver parenchymal cell clone (BC) and by 3 subclones derived from BB cells showed that these cloned cells synthesized similar types of collagen. Apparently, parenchymal cells play an essential role in the hepatic connective tissue metabolism in normal and pathological conditions.