Interleukin-1 and interleukin-2 activity in chronic hepatitis B virus infection.

Abnormalities of lymphocyte proliferation in chronic hepatitis B virus infection are well documented, although the underlying mechanisms are poorly understood. To determine whether these defects may be secondary to disordered lymphokine production, we have simultaneously assayed interleukin-1 and interleukin-2 production in 31 chronic carriers of the hepatitis B virus. Supernatants from mononuclear cells cultured both in the presence and absence of lipopolysaccharide contained significantly increased quantities of interleukin-1 activity in patients compared with normal controls (p less than 0.01). Lysates of monocytes from patients also contained more interleukin-1 than those of controls (p less than 0.05) in the presence of lipopolysaccharide or silica, or both. These results indicate that interleukin-1 production is markedly elevated in patients with chronic hepatitis B virus infection, whereas in contrast, interleukin-2 production was found to be reduced in these patients (p less than 0.01). As one of the biological properties of interleukin-1 is to stimulate fibroblasts to produce collagen, the relationship between fibrosis in the liver biopsy specimen and interleukin production was examined. There was a highly significant correlation (p less than 0.001) between interleukin-1 production and the severity of fibrosis, suggesting that this lymphokine may be closely related to the development of cirrhosis in such patients.

Expression of pre-S gene-encoded proteins in liver and serum during chronic hepatitis B virus infection in comparison to other markers of active virus replication.

Pre-S gene-encoded proteins of the hepatitis B virus (HBV) were studied in the liver by immunofluorescence and in serum by radioimmunoassay in 30 patients with chronic HBV infection. The results were compared with molecular hybridization analysis of HBV-DNA in liver and serum, with serum hepatitis B e antigen/antibody (HBeAg/anti-HBe) status and with underlying liver histology. Pre-S peptides were detected in the serum of 11 patients, 10 of whom were positive for serum HBV-DNA and/or liver hepatitis B core antigen. Only 4 of these patients were HBeAg positive. The prevalence of serum pre-S among HBV replicating carriers was 59% (10/17) compared to only 8% (1/13) among those with non-replicating virus (P less than 0.01). All patients with circulating pre-S peptides had active liver disease. Anti-pre-S was detected in the serum of only 4 patients, 3 with integrated HBV-DNA. In contrast to serum findings, pre-S peptides were detected in the liver of all patients with histochemically demonstrable hepatitis B surface antigen (HBsAg), regardless of HBV replicative status. HBsAg carriers with integrated HBV-DNA had abundant cytoplasmic pre-S1 and pre-S2 localized in numerous ground-glass hepatocytes. It is concluded that pre-S peptides are usually displayed in the liver simultaneously with histochemically detectable HBsAg; they are secreted in the serum in association with high HBV replication and release of HBV particles, but in the absence of episomal HBV replication, pre-S peptides seem to be largely retained within hepatocytic membranes.

Leucocyte hepatitis B virus DNA in acute and chronic hepatitis B virus infection.

In the present study we have investigated 53 patients with a spectrum of acute and chronic hepatitis B virus (HBV) infection for the presence of leucocyte HBV-DNA with the aid of molecular techniques. HBV-DNA was detected in peripheral blood mononuclear cells of 31 of 45 (69%) of chronic HBsAg carriers and 2 of 8 (25%) patients with acute hepatitis B. Although HBV-DNA was detected more frequently in leucocytes from those HBsAg carriers seropositive for HBeAg (79%), 50% of those with anti-HBe in serum had leucocytes positive for HBV-DNA independent of the presence of serum HBV-DNA. Examination of various leucocyte subpopulations showed the presence of HBV-DNA in polymorphonuclear leucocytes as well as T- and non-T-enriched mononuclear cell fractions. The HBV-DNA identified was predominantly 3.2-kilobase (kb), while higher molecular weight sequences were rarely detected, and lower molecular weight sequences indicative of active viral replication were not observed. These data indicate that although leucocytes do not actively support viral replication, they frequently harbour 3.2-kb HBV-DNA and may act as a reservoir for infection and, more importantly, since leucocytes contaminate several body secretions, may be involved in virus transmission.

Failure of exogenous interleukin 1 and interleukin 2 to correct decreased lymphocyte transformation in chronic hepatitis B virus carriers.

To test the hypothesis that reduced lymphocyte transformation in response to PHA in chronic hepatitis B virus infection might be due to deficient lymphokine production, lymphocyte transformation was measured in the presence or absence of exogenous interleukin 1, interleukin 2 or both, or, as a source of mixed lymphokines, supernatants from mixed lymphocyte reactions. The response to PHA was significantly impaired in patients compared to controls, but was not corrected by interleukin 1, interleukin 2 or supernatant from mixed lymphocyte reactions over a wide range of concentrations. Variation of the proportion of monocytes in culture or the addition of indomethacin had no effect on lymphocyte transformation. Thus, reduced lymphocyte proliferation in response to PHA in patients with chronic hepatitis B virus infection cannot be attributed to deficient lymphokine production or to active suppression by monocytes or prostaglandins and a direct role for the hepatitis B virus or a viral product is under investigation.