Distribution of collagen type I and type III and of two collagenous components of basement membranes in the human liver.

The distribution of collagen type I and III and of the basement membrane collagens type IV and alphaA (alphaB)2 in normal and fibrotic human livers has been studied by indirect immunofluorescence using type specific antibodies. Collagens type I as well as type III are present in normal livers in the blood vessel walls and the wall of biliary ducts of the portal tracts. In the parenchyma both types are visible along the sinusoids. Basement membrane collagens are only present in the connective tissue of portal canals and of central veins whereas in the parenchyma both type IV and alphaA (alphaB)2-collagen are nearly absent. In the tissue of fibrotic livers basement membrane collagens are also found in the parenchyma in similar distribution as type I and III.