Autoantibodies to collagen in patients with chronic liver diseases.

Sera of patients with various liver diseases were investigated for the presence of autoantibodies to type I collagen with a sensitive radioimmunoassay employing 3H-labelled collagen type I. A high percentage (69%) of patients with chronic liver diseases, equally distributed between chronic active hepatitis and alcoholic liver disease, was found to possess antibodies to denatured type I collagen, while no antibodies against native collagen were found. These antibodies belonged predominantly to the IgA immunoglobulin class. None of the patients with acute hepatitis or cholestatic liver disease, nor the healthy individual investigated had IgA-anticollagen antibodies. These findings may be useful as a parameter for the detection of chronic liver disease.