Homo sapiens Raw sequence reads

Hepatitis B virus (HBV)-associated acute liver failure (ALF) is a dramatic clinical syndrome leading to death or liver transplantation in 80% of cases. However, the pathogenesis of ALF remains largely unknown. Here, we performed a comprehensive genetic and functional characterization of the virus and the host in liver tissue from HBV-associated ALF and compared the results with those of classic acute hepatitis B in chimpanzees. In contrast with acute hepatitis B, HBV strains detected in ALF livers displayed highly mutated HBV core antigen (HBcAg), associated with increased HBcAg expression ex vivo, which was independent of viral replication levels. Combined gene and microRNA expression profiling revealed a dominant B-cell-driven disease signature, with extensive intrahepatic production of IgM and IgG in germline configuration exclusively targeting HBcAg with subnanomolar affinities, and complement deposition. Thus, HBV-ALF appears to be an anomalous T-cell-independent, HBV core-driven B-cell disease, which results from the rare and unfortunate encounter between a host with an unusual naïve B-cell repertoire and an infecting virus with a highly mutated core antigen.