Circulating levels and liver tissue distribution of intercellular adhesion molecule-1 during beta-interferon therapy of hepatitis C virus-associated chronic active liver disease.

Abstract

Intercellular adhesion molecule-1, an immunoglobulin supergene family member, is known to account for important steps in cell activation and the immune response. By a non-isotopic slot-dot immunoblotting assay, we measured circulating levels of intercellular adhesion molecule-1 in 26 patients with hepatitis C virus-associated chronic active liver disease before and after beta-interferon therapy, in 6 patients with non-A, non-B acute self-limiting hepatitis and in 13 healthy subjects. Circulating intercellular adhesion molecule-1 was found in 10 of 13 (77%) normal controls at low concentrations which were not statistically different from those measured in patients with hepatitis C virus-associated chronic active liver disease responsive to beta-interferon, whereas significantly higher levels were found in unresponsive patients. Higher serum intercellular adhesion molecule-1 levels were found in 4 of 10 (40%) beta-interferon-responsive patients compared with 13 of 16 (18%) unresponsive patients. Intercellular adhesion molecule-1 levels persisted after discontinuation of beta-interferon treatment and did not correlate with hepatocytolysis (as indicated by alanine aminotransferase serum activity) either in chronic active liver disease or acute hepatitis. However, a good correlation was found between intercellular adhesion molecule-1 and its expression on liver cells, thus emphasizing that induced circulating levels may reflect the state of activation at the sites of the inflammatory process. These data strongly support the view that intercellular adhesion molecule-1 plays an important role in liver cell damage in hepatitis C virus-associated acute and chronic liver disease, and that its circulating levels may be a good prognostic parameter of responsiveness to beta-interferon therapy.