Intrahepatic up-regulated expression of extracellular matrix protein receptors in chronic active hepatitis type B.

The aim of the present study was to investigate the differences in expression of beta 1 integrins between normal liver and the inflamed livers of patients with chronic active hepatitis B. Immunohistochemical staining with monoclonal antibodies that specifically recognize the common beta 1 chain and five different alpha subunits has been performed in frozen liver biopsy sections from 10 patients with chronic active hepatitis B and from 4 patients with normal livers. The major findings of our study were de novo expression in liver with chronic active hepatitis B of alpha 2 and alpha 3 subunits on both periportal hepatocytes and on lobular hepatocytes in close proximity to lymphocyte infiltrates. These results indicate the existence of an up-regulatory process in the expression of beta 1 integrins, especially the alpha 2 and alpha 3 subunits, in the inflamed liver tissue from patients with chronic active hepatitis B, suggesting that these integrins could play an important role in the development of liver fibrosis and in regulating intrahepatic lymphocyte migration.