Suppressor T-cell activity in chronic hepatitis B-virus infection: relationship with the presence of HBV-DNA in serum

CD8low T-cell subpopulation is increased in patients with chronic hepatitis B virus infection

Recent studies suggest that CD8(+) T cells with down-regulated CD8 expression (CD3(+)CD8(low) T cells) represented as a distinct phenotype of CD8(+) T cells are increased and linked to disease severity in some chronically persistent infection, such as chronic HIV and parasite infection. However, the role of CD3(+)CD8(low) T cells in the context of chronic HBV infection is poorly understood. In this study, peripheral blood samples of 47 chronic hepatitis B patients and 19 healthy controls were collected and tested for the frequency and phenotype of CD8(low) T cells. The circulating CD8(low) T cells were significantly more frequent in the patients compared to those in healthy controls, and the CD8(low) T cells in the patients expressed less IFN-γ and more mTGF-β1 than those in the controls, suggesting their type-2 polarized and suppressive properties. Meanwhile, the concentrations of plasma soluble HLA class I molecules were found elevated in the patients, and positively associated with the frequencies of CD8(low) T cells. Furthermore, the CD8(low) T-cell frequency in the HLA-A2-positive patients (n=21) was found negatively correlated with the T-cell responsiveness against the HBc₁₈₋₂₇ peptide, the latter was impaired as revealed by IFN-γ Elispot assay. Our findings suggested that a better understanding of the involvement of CD8(low) T cells in chronically persistent HBV infection would add to our knowledge of the impaired T-cell response in the patients.

Therapeutic response of chronic active hepatitis B (CAHB) to a new immunomodulator: AM3. Immunohematological effects

AM3, a biological response modifier (BRM) of polysaccharide/protein nature, was given by the oral route to 13 patients with chronic active hepatitis B (CAHB). After 12 months of daily treatment, 8 patients cleared serum HBV-DNA and HBeAg together with ALT normalization. Immunohaematologic studies showed how time of inhibition of viral replication was related to significant decreases of CD4, CD8 and B cell blood lymphocytes. After serum viral elimination, however, a significant haematologic rebound of peripheral blood mononuclear cells (PMNC): CD3, CD4 and CD8 lymphocytes was seen. These data, suggest that the antiviral activities of AM3 may be due to its immunodulatory capacities. These promising results, together with the absence of any side effects, justify the entry to trials with a larger number of patients. Furthermore, treatment with AM3 may help to elucidate the pathophysiology of CAHB.

Transforming growth factors beta 1 and alpha in chronic liver disease. Effects of interferon alfa therapy

BACKGROUND

Cirrhosis is a diffuse process of hepatic fibrosis and regenerative nodule formation of unknown pathogenesis. Transforming growth factor (TGF) beta 1 induces the production of extracellular matrix proteins by liver cells and has been implicated in the pathogenesis of hepatic fibrosis in laboratory animals. TGF alpha is a hepatocyte mitogen that participates in liver regeneration.

METHODS

Using Northern blot analysis, we studied the expression of TGF beta 1 messenger RNA (mRNA) in liver specimens from 42 patients with chronic hepatitis and cirrhosis and 12 subjects with either normal or fatty livers. The results were correlated with measurements of procollagen Type I mRNA in liver tissue, procollagen Type III peptide in serum, and the degree of histologic injury. We also investigated whether TGF alpha mRNA would be detectable in biopsy specimens of livers with proliferative activity.

RESULTS

TGF beta 1 mRNA expression correlated closely with the expression of procollagen Type I mRNA (r = 0.94) and serum procollagen Type III peptide (r = 0.89) and with the histologic activity index (r = 0.73). All patients with increased fibrogenic activity (serum procollagen Type III peptide level, greater than 11.9 micrograms per liter) had increased levels of TGF beta 1 mRNA (2 to 14 times the levels in the control group or in patients with normal fibrogenic activity), and both TGF alpha and H3 histone (a marker of DNA synthesis) mRNAs were detectable in patients with regenerative nodules. Six of eight patients with hepatitis C treated with interferon alfa for one year had sustained clinical responses with normalization of serum procollagen Type III peptide and aminotransferase activity. All these patients had normal levels of TGF beta 1 mRNA in liver specimens obtained at the end of the year.

CONCLUSIONS

TGF beta 1 may have an important role in the pathogenesis of fibrosis in patients with chronic liver disease, and TGF alpha expression may be associated with liver regeneration in these patients.