Increased lysyl oxidase activity in culture medium of nonparenchymal cells from fibrotic livers.

Lysyl oxidase, which plays an important role in collagen deposition in chronic liver diseases, was studied in nonparenchymal cell cultures from fibrotic human livers. Liver biopsy specimens were obtained from control patients without apparent hepatic disease, and from patients with chronic persistent hepatitis, chronic active hepatitis, or liver cirrhosis. Nonparenchymal cells from biopsy specimens were cultured. At the third passage of the culture, lysyl oxidase activity was measured in the culture medium and cell layer. Most of the activity in the culture medium of cirrhotic liver cells was significantly higher than that in the medium of liver cells from controls or from patients with chronic hepatitis, whereas no significant difference in activity was noted between chronic persistent hepatitis and chronic active hepatitis cells. In patients with chronic hepatitis, lysyl oxidase activity in the culture medium from liver cells of alcoholics was significantly higher than that in the medium from liver cells of nonalcoholics. Thus, increased lysyl oxidase activity was found in the medium of nonparenchymal cell cultures from patients with cirrhosis and from alcoholics with chronic hepatitis. This increased activity may be related to fibrotic processes in the liver.