Identification of circulating type II pre-dendritic cells (pDC2) and its clinical significance in chronic hepatitis B virus infection / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To investigate the characteristics of circulating type II pre-dendritic cells (pDC2) and evaluate its role in patients with chronic hepatitis B virus infection.</p><p><b>METHODS</b>The quantitative alterations of pDC2 in 27 chronic HBV-infected patients as treated group and 15 healthy individuals as a control group were analyzed by using flow cytometry based on the comparison of CD4+/CD8+ ratios of T lymphocyte subsets between the two groups. The IFN-alpha-producing ability of pDC2 after incubation was determined by ELISA.</p><p><b>RESULTS</b>The percentage of pDC2 (0.096 +/- 0.086) from the peripheral blood in chronic HBV-infected patients were significantly lower than that (0.304 +/- 0.093) from the normal controls (P less than 0.001) while the CD4+/CD8+ ratios were higher than those in normal controls (P less than 0.01). The values of IFN-alpha-producing function and IL-12 of circulating pDC2 in chronic HBV-infected patients group were significantly lower than those in healthy subjects (P < 0.001). The percentage of pDC2 and CD4+/CD8+ ratios were higher in the patients positive for HBV DNA in sera than those in patients negative for HBV DNA in sera (P < 0.01).</p><p><b>CONCLUSION</b>The decreased number of circulating pDC2 and IFN-alpha-producing function from peripheral blood in patients with chronic hepatitis B virus infection may result in the decline of host immune response, which may partially contribute to the disease progress of HBV infection and existence of viral genomic DNA in patient's sera.</p>

Antiviral effect of human CTLs activated by HBsAg stimulated dendritic cells in vitro / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To investigate the ability of human dendritic cells (DCs) inducing specific T lymphocyte response and inhibit the expression of HBeAg and HBsAg in 2.2.15 cell culture supernatant.</p><p><b>METHODS</b>DCs were prepared from peripheral blood mononuclear cells induced with granulocyte macrophage colony-stimulating factor(GM-CSF) and interleukin 4. DCs was impulsed with pure HBsAg before DCs maturation and cocultured with self-blood T lymphocyte, while DCs without pure HBsAg stimulated group, T lymphocyte group and only T lymphocyte group were prepared as control group. The culture supernatant of 2.2.15 cell with stimulated T lymphocytes was collected on day 1, day 3, day 5 and day 7, respectively. The expressed levels of HBeAg and HBsAg were detected by ELISA method.</p><p><b>RESULTS</b>DCs after antigen stimulation had a strong ability to present antigen and induce immune activation, DCs after loading with antigen in normal control and chronic hepatitis patients group had stronger stimulative ability for T lymphocytes proliferation than that of DCs without loading with antigen and only T lymphocyte group(P less than 0.01). The stimulating ability of DCs had a positive correlation to the dosage of loaded antigen; CTLs produced as a result of DCs stimulation had a specific inhibitive effect on the expression of HBeAg in 2.2.15 cell supernatant,but not on the expression of HbsAg.</p><p><b>CONCLUSION</b>Human dendritic cells stimulated with HBsAg in vitro can efficiently present antigen and stimulate the production of specific CTLs to HBV, which can efficiently inhibit the expression of HBeAg in 2.2.15 cell supernatant- DC vaccine may become an antiviral therapy strategy for chronic hepatitis B virus infected patients in future.</p>