[Correlation of the expression of NF-κB p65 and hepatic fibrosis in hepatitis patients].

OBJECTIVE: To explore the relationship between the expression of NF-κB p65 and hepatic fibrosis in chronic hepatitis B (CHB) patients. METHODS: Sixty CHB patients with hepatic fibrosis underwent liver biopsy to determine the stages of liver fibrosis (S0-S4). The distribution and expression of collagens I, III and NF-κB p65 in different stages of fibrosis in liver tissue were observed by immunohistochemistry and the results analyzed statistically. RESULTS: The expression of NF-κB p65 was positively correlated with the stage of hepatic fibrosis. That was S4 > S3 > S2 > S1 (S0) (P < 0.01). And it was also positively correlated with the expression of collagens I and III (P < 0.01). CONCLUSION: The elevated expression of NF-κB p65 is closely associated with the occurrence and development of hepatic fibrosis. Its mechanism is probably related with the increased secretion of collagens I and III after the activation of hepatic stellate cell.

[Lamivudine, interferon-alpha and oxymatrine treatment for the surviving hepatic failure patients with hepatitis B].

OBJECTIVE: To investigate the effect of lamivudine, interferon alpha and oxymatrine treatment for surviving hepatic failure patients with hepatitis B. METHODS: 200 hepatitis B patients, including 100 subacute or acute-on-chronic hepatic failure survivals (group A), and 100 chronic (group B, n=100) hepatic failure survivals, were enrolled in this study. Patients in group A received interferon alpha (n=35), lamivudine (n=33) , or combinational lamivudine and oxymatrine (n=32) therapy for six months; Patients in group B received lamivudine (n=49), or combinational lamivudine and oxymatrine (n=51) therapy for six months, respectively. After the treatment, all patients were followed-up for six months. RESULTS: At the end of follow-up, all patients in group A survived, while in group B three patients (6.1%) receiving lamivudine, and four (7.8%, P>0.05) receiving combinational therapy died; more than 90% of all survivals had their HBV DNA loss. The HBeAg/anti-HBe seroconversion rate in patients of group A treated with interferon alpha (9/17, 52.9%) was higher than that in patients treated with combinational lamivudine and matrine (5/16, 31.3%, P<0.05), which was higher than that in the patients treated with lamivudine alone (1/17, 5.9%, P<0.01), and the Knodell histological activity index score in patients treated with lamivudine (7.2+/-0.8, P<0.05) was lower than that in patients treated with interferon alpha (8.2+/-1.3, P<0.05), and the best efficacy was found in receiving combinational therapy (6.9+/-0.7, P<0.01); Lamivudine or lamivudine in combination with matrine significantly inhibited the intrahepatic inflammatory activities, but had no effect on the existing fibrosis in group B patients. CONCLUSION: Long term nucleotide analogues treatment may delay the progress of fibrosis in hepatitis B-induced hepatic failure survivals, and the administration of matrine in time may further enhance the anti-fibrotic effect of nucleotide analogues.

Induction of hepatitis C virus-specific cytotoxic T and B cell responses by dendritic cells expressing a modified antigen targeting receptor.

AIM: To find a novel antigen (Ag) presentation strategy to improve the immune responses induced by dendritic cell (DC) vaccine expressing hepatitis C virus (HCV) core antigen (pcDNA3HCV C-Fc) in Balb/c mice (H-2d). METHODS: pcDNA3HCV C-Fc plasmid and eukaryotic expression vector pcDNA3 were injected into mice sc. Immune responses to pcDNA3HCV C-Fc were studied. Meanwhile the effect of pcDNA3HCV C-Fc on anti-translated subcutaneous tumor of SP2/0 cells stably expressing HCV C Ag (SP2/0-HCV C-FC) was also studied. Anti-HCV C in serum was detected by enzyme-linked immunoadsordent assay (ELISA) and HCV specific cytotoxic T lymphocyte (CTL) activity was measured by LDH release assay. After 3 wk of DNA immunization, the cells of SP2/0-HCV C-FC were inoculated into mice subcutaneously and tumor growth was measured every 5 d. The survival rate and living time of mice were also calculated. RESULTS: After 4 wk of DC immunization, the A(450 nm) values of sera in mice immunized with pcDNA3HCV C-Fc-DC and pcDNA3-DC were 0.56+/-0.17 and 0.12+/-0.03 respectively. The antibody titres in mice codeliveried with pcDNA3HCV C-Fc with DC were significantly higher than those of mice injected with pcDNA3-DC. The HCV specific CTL activities in mice coinjected with DC and pcDNA3HCV C-Fc or empty expression vectors were (73.2+/-3.1)% and (24.4+/-8.8)%, which were significantly higher than those of mice injected with water. The DC vaccine could evidently inhibit tumor growth, prolong the survival time of mice and improve the survival rate of mice and these effects could be improved by HCV C-Fc (pcDNA3HCV C-Fc) gene codelivered. CONCLUSION: DC vaccine has a strong antigenicity in humoral and cellular immunities, which can be promoted by transduced pcDNA3HCV C-Fc expressing HCV C or Fc. Thus, pcDNA3HCV C-Fc-transduced DCs may be a promising candidate for a CTL-based vaccine against HCV.

DC-SIGN: binding receptors for hepatitis C virus.

OBJECTIVE: To review the recent developments in and research into binding receptors of hepatitis C virus (HCV) and especially the role of dendritic cell-specific adhesion receptor (DC-SIGN) in HCV. DATA SOURCES: Both Chinese- and English-language literature was searched using MEDLINE (2000 - 2003) and the databank of Chinese-language literature (2000 - 2003). STUDY SELECTION: Relevant articles on DC-SIGN and HCV binding receptors in recent domestic and foreign literature were selected. DATA EXTRACTION: Data were mainly extracted from 40 articles which are listed in the references section of this review. RESULTS: DC-SIGN, a dendritic cell-specific adhesion receptor and a type II transmembrane mannose-binding C-type lectin, is very important in the function of dendritic cells (DC), both in mediating naïve T cell interactions through ICAM-3 and as a rolling receptor that mediates the DC-specific ICAM-2-dependent migration processes. It can be used by HCV and other viral and bacterial pathogens including human immunodeficiency virus (HIV), Ebola virus, CMV and Mycobacterium tuberculosis to facilitate infection. Both DC-SIGN and DC-SIGNR can act either in cis, by concentrating virus on target cells, or in trans, by transmission of bound virus to a target cell expressing appropriate entry receptors. Recent report showed that DC-SIGN not only plays a role in entry into DC, HCV E2 interaction with DC-SIGN might also be detrimental to the interaction of DC with T cells during antigen presentation. CONCLUSIONS: DC-SIGNs are high-affinity binding receptors for HCV. The clinical strategies that target DC-SIGN may be successful in restricting HCV dissemination and pathogenesis as well as directing the migration of DCs to manipulate appropriate immune responses in autoimmunity and tumorigenic situations.

[Acceleration of mixed lymphocyte reaction by HCV C-Fc gene-transferred murine dendritic cells].

AIM: To observe the metergasis of murine dendritic cells (DCs) transfected with HCV C-Fc gene through electroporation. METHODS: Mononucleocytes isolated from murine bone marrow were co-cultured with rmGM-CSF and rm-IL-4 for 7 days. Morphological characteristics of the cultured cells were observed under scan electron-microscope (SEM) and the expression of DEC205 on the cells was detected by FACS. DCs derived from the culture were transfected with plasmids containing HCV C-Fc gene. HCV C-Fc level in the transfected cells was detected by indirect immunofluorescence assay. MLR was studied with DCs and T cells. RESULTS: Following 7-day culture, a large number of cells with typical characteristics of DC were observed. The HCV C-Fc level in the transfected DCs was higher. MLR was stimulated markedly by DCs transfected with HCV C-Fc gene in comparison with the control group. CONCLUSION: A large number of DCs could be generated from murine bone marrow mononucleocyte cultures supplemented with GM-CSF and IL-4 for 1 week. The function of DCs transfected with pcDNA3HCV C-Fc was enhanced in MLR.

DC-SIGN: binding receptor for HCV?

DC-SIGN, a dendritic Cell-specific adhesion receptor and a type II transmembrane mannose-binding C-type lectin, is very important in the function of DC, both in mediating naive T cell interactions through ICAM-3 and as a rolling receptor that mediates the DC-specific ICAM-2-dependent migration processes. It can be used by viral and bacterial pathogens including Human Immunodeficiency Virus (HIV), HCV, Ebola Virus, CMV and Mycobacterium tuberculosis to facilitate infection. Both DC-SIGN and DC-SIGNR can act either in cis, by concentrating virus on target cells, or in trans, by transmission of bound virus to a target cell expressing appropriate entry receptors. Recent work showed that DC-SIGN are high-affinity binding receptors for HCV. Besides playing a role in entry into DC, HCV E2 interaction with DC-SIGN might also be detrimental for the interaction of DC with T cells during antigen presentation. The clinical strategies that target DC-SIGN may be successful in restricting HCV dissemination and pathogenesis as well as directing the migration of DCs to manipulate appropriate immune responses in autoimmunity and tumorigenic situations.

RNA interference: antiviral weapon and beyond.

RNA interference (RNAi) is a remarkable type of gene regulation based on sequence-specific targeting and degradation of RNA. The term encompasses related pathways found in a broad range of eukaryotic organisms, including fungi, plants, and animals. RNA interference is part of a sophisticated network of interconnected pathways for cellular defense, RNA surveillance, and development and it may become a powerful tool to manipulate gene expression experimentally. RNAi technology is currently being evaluated not only as an extremely powerful instrument for functional genomic analyses, but also as a potentially useful method to develop specific dsRNA based gene-silencing therapeutics. Several laboratories have been interested in using RNAi to control viral infection and many reports in Nature and in Cell show that short interfering (si) RNAs can inhibit infection by HIV-1, polio and hepatitis C viruses in a sequence-specific manner. RNA-based strategies for gene inhibition in mammalian cells have recently been described, which offer the promise of antiviral therapy.