Expression of beta-2-microglobulin on hepatocytes after liver transplantation.

The distribution of beta 2-microglobulin was studied by an immunoperoxidase method in paraffin sections from sixteen serial graft liver biopsy samples taken after liver transplantation from four patients who had received transplants for advanced primary biliary cirrhosis. Mild to moderate acute rejection was diagnosed in three of the patients. Expression of beta 2-microglobulin on hepatocyte membranes was greater during rejection, and tended to fall after the rejection episode. However, a few hepatocytes continued to display beta 2-microglobulin on their cell membranes. Rejection was characterised histologically by infiltration of portal tracts with lymphoid cells, and cholestasis. Enhanced display of beta 2-microglobulin on hepatocytes probably reflects display of HLA A, B, and C antigens and may be associated with increased susceptibility of the affected cells to T-lymphocyte-mediated immune attack.