Impaired non-viral specific immune function of dendritic cell does not interfere with clearance and cytotoxic T lymphocyte response to HBV or HCV / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To investigate the correlation between impaired non-viral specific immune function of dendritic cell (DC) and viral clearance and cytotoxic T lymphocyte (CTL) response to HBV or HCV in patients with HBV and HCV coinfection.</p><p><b>METHODS</b>Twenty-five patients with HBV and HCV coinfection were investigated in this study. In 1994 and 2002, biochemical and virological markers and quantitative serum HBV DNA and HCV RNA levels were detected in these patients. According to the virus clearance status, these patients were divided into 4 groups: 14 patients with both HBV and HCV clearance (Group A), 6 patients with HCV clearance only (Group B), 3 patients with HBV clearance only (Group C), and 2 patients with persistent infection of HBV and HCV (Group D). Phenotypes and immune functions of monocyte-derived DCs were compared between these groups. 51Cr release assay were used to measure CTL response to epitopes derived from HBV, HCV or influenza virus (as positive control) in HLA-A2+ patients.</p><p><b>RESULTS</b>Impaired non-viral specific immune functions of DCs were observed in group B, C and D compared with group A and normal donors (Group N). These impaired functions included CD86 decreasing expression and lower capacity to stimulating allogenic T cells and uptaking antigen. The specific CTL response to HBV- and HCV-derived peptides could be induced in group A (12/12). The specific CTL response to HBV-derived peptides or to HCV-derived peptides could be induced in group C (3/3) or B (5/5), respectively. But the specific CTL response to both of two HBV-derived peptides or two HCV-derived peptides could not be induced in group C (0/3) or B (0/5), respectively. And no CTL response to HBV or HCV-derived peptides could be induced in groups D (0/1) and N (0/4).</p><p><b>CONCLUSION</b>1. The results suggest that specific CTL response to HBV or HCV play a vital role in the viral clearance. 2. The DCs with impaired non-viral specific immune functions exist in chronic patients with HBV and/or HCV infection, but do not interfere with clearance and CTL response to HBV or HCV. It is reasonable to speculate that impaired functions of DCs result from viral infection.</p>

Dendritic cells originated from the peripheral blood in chronic hepatitis B patients can induce specific T cell immune response / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To study whether dendritic cells (DCs) derived from the peripheral blood in chronic hepatitis B patients can induce specific T cell immune response.</p><p><b>METHODS</b>(1)The subjects were divided into 3 groups: chronic hepatitis B group (CHB), acute hepatitis B group (AHB), and normal donor group (ND). The peripheral blood mononuclear cells (PBMCs) isolated from those subjects were stimulated with HBcAg 18 to 27 CTL epitope peptide, and intracellular cytokine staining (ICCS) was used for detecting IFN-gamma, IL-2 and TNF-alpha produced by CD8+ T cell. (2) DCs generated from PBMCs were pulsed with HBcAg 18 to 27 CTL epitope peptide, then were cocultured with autologous lymphocytes for 10 days to induce antigen-specific T cell, which was assessed by ICCS and cytotoxic assay.</p><p><b>RESULTS</b>(1) The memory effect of the PBMCs from AHB group to HBcAg 18 to 27 CTL epitope peptide was stronger than that from CHB or ND group (t=2.508-3.305, P<0.05). (2)After lymphocytes were cocultured with DC treated with HBcAg 18 to 27 CTL epitope peptide, antigen-specific T cell effect was induced. And the killing rates were (57.0+/-23.0)%, (49.5+/-20.2)%, (21.8+/-12.9)% at the effector/target of 30:1, 10:1, 3:1, which were higher than that in control group.</p><p><b>CONCLUSIONS</b>The memory T cells against HBV antigen lacks in CHB patients. DCs from CHB patients pulsed with HBcAg 18 to 27 epitope peptide can induce HBV antigen-specific T cell, which can kill specific target cells and produce cytokines involved in virus clearance.</p>

Comparison of hepatitis B virus serotype and genotype among HBsAg positive hepatitis B patients in a northern and a southern city of China / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To understand HBV serotypes and genotypes epidemiology in a northern city and a southern city in China.</p><p><b>METHODS</b>Using polymerase chain reaction (PCR) and direct sequencing of HBV DNA PCR products, the serotypes and genotypes of HBV in 530 from HBsAg positive samples. The enrolled patients were from Harbin, a northern city and Lianjiang, a southern city in China.</p><p><b>RESULTS</b>Comparison of the serotypes and genotypes of HBV between Harbin and Lianjiang showed that adrq+ was the most predominant hepatitis B virus serotype in both Harbin and Lianjiang (87.2% and 73.5%,respectively), adw2 was the next (12.0% and 25.7%, respectively); genotype C was the most frequent in Harbin and Lianjiang (87.8% and 73.2%, respectively), and genotype B was the next (12.2% and 26.1%, respectively) only 1 patient was infected by genotype D, and 1 patient was found to be co-infected by genotype B and C in Lianjiang.</p><p><b>CONCLUSION</b>The results suggest that the percentage of HBV serotypes and genotypes between Harbin and Lianjiang was significantly different (P less than 0.001), but the main HBV serotype and genotype of the two cities were similar.</p>