Splenectomy induces biochemical remission and regeneration in experimental murine autoimmune hepatitis

Autoimmune hepatitis (AIH) is a chronic immune-mediated inflammatory liver disease. It is known that AIH originates not from the spleen but from the liver itself. Nonetheless, most details of the etiology and pathophysiology are unknown. We induced experimental murine AIH (emAIH) in NOD/Ltj mice by single administration of a replication-deficient adenovirus and performed splenectomy during late-stage disease. Biochemical disease remission occurred, which was characterized by improvement in transaminase levels. The causes of this remission included a shift in the transcriptomic signature of serum proteins toward regeneration. At the cellular level, there was a marked decrease in activated CD8⁺ T cells and an increase in intrahepatic regulatory T cells (Tregs). Here, intrahepatic Treg numbers correlated with biochemical remission. Notably, an imbalance in the T-cell/B-cell ratio was observed, with a disproportionate increase in total B cells. In summary, intrahepatic increases in Tregs, biochemical remission, and regeneration could be induced by splenectomy in the late stage of emAIH.