Effect of neonatal thymectomy on D-galactosamine induced liver injury in mice

Abstract

To evaluate the various influences of neonatal thymectomy on galactosamine (Gal-N) induced tiver injury in A/J mice, we serially observed histological changes in the liver and serum autoantibody to liver-specific membrane lipoprotein (LSP) in normal mice, mice thymectamized 2-3 days after birth (Tx 2-3 mice), and those thyrnectornized 5 days after birth (Tx 5 mice). In the normal and Tx 2-3 mice, massive hepatocyte necrosis was observed in the acute stage. Then in the normal mice, hepatitis healed 1 week after Gal-N administration, and autoantibody to LSP was always negative. However, in Tx 2-3 mice, considerable mononuclear cell infiltration in the portal area was frequently observed even 3 months after Gal-N administration, and the serum level of autoantibody to LSP remained high. On the other hand, Tx 5 mice showed findings similar to those in the normal mice. These results suggest that healing of Gal-N induced liver injury is delayed by thymectomy 2-3 days after birth due to sensitization with LSP preparations.