REPLICATION OF HEPATITIS-A VIRUS AND PROCESSING OF PROTEINS

Isolation and propagation of hepatitis A virus (HAV) in cell culture is routinely possible. All primary HAV isolates and most established virus strains, however, show a protracted replication behaviour and tend to establish a persistent infection. Rapidly replicating, cytolytic variant viruses can be selected from persistently infected cultures under distinct conditions. Factors critical for the outcome of HAV infection include the genetics of the virus, the physiological state of the infected cell, the presence of defective interfering particles, syn thesis and encapsidation of viral RNA and possibly synthesis and processing of viral proteins. Analysis of the latter events have proved to be difficult. Only seven of the 11 peptides coded for by the HAV genome have been experimentally identified and the sequence of cleavages by which they are released from the precursor polyprotein is still a matter of discussion.