Expression of beta 2-microglobulin on hepatocytes in acute and chronic type B hepatitis.

beta 2-Microglobulin display was examined in 131 liver biopsies from patients with acute and chronic type B hepatitis, using an indirect immunoperoxidase method. Enhanced expression of beta 2-microglobulin on hepatocyte membranes was observed in patients with acute hepatitis, chronic active hepatitis with moderate to severe activity and cirrhosis, when compared with normal liver. In acute hepatitis, beta 2-microglobulin-positive hepatocytes were mainly observed in perivenular areas in association with bridging necrosis. In chronic hepatitis, beta 2-microglobulin-positive hepatocytes were observed mainly in periportal zones and in some areas of lobular activity. Diffuse-enhanced display of beta 2-microglobulin on hepatocytes was observed in 5 of 6 patients treated with lymphoblastoid interferon as part of a trial of antiviral therapy. The mechanism by which beta 2-microglobulin display is enhanced on hepatocytes in patients not treated with interferon is uncertain. However, display of beta 2-microglobulin on hepatocytes probably reflects display of HLA-A, B and C antigens and may influence the course of hepatitis B virus infection by increasing susceptibility of the affected cells to T cell-mediated immune attack.