Quantification of viral RNA in multiple pieces of explant liver tissue shows distinct focal differences of hepatitis B infection.

Hepatitis B virus (HBV) DNA and RNA were quantified by digital PCR assays in 20-30 tissue pieces from each of four liver explants with cirrhosis caused by HBV. The within-patient variability of HBV RNA levels between pieces was up to thousand-fold. Core RNA and S RNA levels were similar and correlated strongly when replication was high, supporting transcription from cccDNA. By contrast, enhanced expression of S RNA relative to cccDNA and core RNA in patients with medium-high or low replication supports that HBV surface antigen (HBsAg) can be expressed mainly from integrated HBV DNA in such patients.