In chronic viral type B
hepatitis, the presence in the serum of
pre-S proteins of hepatitis B virus (HBV) envelope reflects viral replication. As peripheral blood mononuclear cells (PBMC) are known to be target cells for HBV replication, the aim of our study was to investigate the clinical relevance of pre-S
protein expression in PBMC. Fifty-seven patients with chronic type B
hepatitis and HBs antigenemia were studied. Following separation using the
Ficoll gradient, the PBMC were lysed and studied for
pre-S proteins by Western blot. HBs Ag and HBc/e Ag were assayed in parallel by radioimmunoassay. HBs Ag was detected in PBMC in 86 percent of cases, HBc/e Ag in 28 percent of cases and
pre-S proteins in 34 percent of cases. A statistically significant association was found between the presence of HBc/e Ag in PBMC and both the serum HBe Ag (chi 2 test, p less than 0.01) and the serum
viral DNA/
DNA polymerase (t test, p = 2.10(-4)). The pre-S
protein expression in PBMC was significantly associated with higher levels of
DNA/
DNA polymerase activity (chi 2 test, p less than 0.05). The expression of
pre-S proteins in PBMC appears therefore to correlate with the HBV viral replication phase. The HBc/e Ag and pre-S
protein detection in PBMC therefore offers a reliable non invasive approach to tissular viral replication. The clinical relevance of pre-S testing in PBMC was illustrated by the study of 12 cases of
chronic active hepatitis positive for anti-HBe but with no or low level of serum
DNA polymerase activity.(ABSTRACT TRUNCATED AT 250 WORDS)