Distribution of collagen types I, III, and V in fibrotic and neoplastic human liver.

The distribution of collagen types I, III, and V in normal and fibrotic human livers and hepatocellular carcinoma was studied by indirect immunofluorescence procedure using type specific antibodies. Type I collagen as well as type III collagen was present in normal liver within the portal tracts and along the perisinusoidal spaces. Basement membrane collagen, type V collagen, was demonstrated only around the bile ducts and vessels of the portal tracts and central veins. In fibrotic liver, both type I and III collagens were found in increased amounts in fibrotic areas. In fibrous septa of active cirrhosis, however, type I collagen as well as type III collagen was abundant, whereas in inactive cirrhosis type I fibers were predominant. Type V collagen was observed in the walls of proliferative bile ductules and vessels in the fibrotic liver, and also along the sinusoids in the periportal areas. In hepatocellular carcinoma, each type of collagen was distributed regularly along the sinusoid-like vascular channels within the tumor.