cDNA clone of hepatitis A virus encoding a virulent virus: induction of viral hepatitis by direct nucleic acid transfection of marmosets.

Direct inoculation of marmoset livers with an in vitro transcription mixture containing cDNA and full-length genomic RNA transcripts of hepatitis A virus resulted in acute viral hepatitis. Elevations in serum levels of liver enzymes were correlated with appearance of antibody to hepatitis A virus. Genomes of infectious hepatitis A virus isolated from the feces of transfected marmosets contained the same mutation as the cDNA template used for transfection. Liver biopsies confirmed that the virus encoded by the cDNA clone induced histopathological changes equivalent to those caused by virulent wild-type virus.