Tratamiento de la hepatitis B: nuevas drogas y oportunidades / Treatment of the hepatitis B: new drugs and opportunities

Las nuevas opciones terapéuticas de la infección por virus de la hepatitis B, (VHB), han mejorado sustancialmente en los últimos años. El interferón recombinante alfa ha sido usado en las últimas dos décadas como el tratamiento de opción, pero desde la década de los noventa se han introducido nuevas drogas que inhiben la replicación del VHB. Los protocolos de tratamiento para diferentes tipos de pacientes, como son hepatitis B y antígeno e positivo (HBeAg +) o negativo (HBeAg -), pacientes con cirrosis hepática, e individuos infestados después del transplante están actualmente en pleno desarrollo. Sin embargo, estamos enfrentando el creciente reto de tomar decisiones terapéuticas cada vez más complejas: ¿Cuál es la mejor droga para cada paciente?, ¿Cuándo debemos comenzar la terapia?, ¿Usamos una terapia combinada, y si es así, qué drogas escogeremos? ¿Qué tiempo debemos tratar a los pacientes con hepatitis B? ¿Existe algún índice que nos ayude en la práctica clínica? Esta revisión presenta el resultado de algunos estudios que quizás nos puedan ayudar a responder estas preguntas.

Therapeutic options for hepatitis B virus (HBV) infection have significantly improved in recent years. Although recombinant interferon alfa has been used for chronic hepatitis B for almost 2 decades, several drugs directly inhibiting HBV replication have been introduced since the late 1990s. Treatment guidelines for different cohorts of patients, such as hepatitis B e antigen (HBeAg) positive and -negative patients, patients with liver cirrhosis, and HBV-infected individuals post liver transplantation, have been developed. However, we face the growing challenge of treatment decisions becoming more complex. In this context, the following questions come to the fore: What is the best drug for which patient? When should we start therapy? Should we use combination therapy, and if so, which agents should be combined? How long should we treat patients with chronic hepatitis B? Are there predictors of response that could help us in clinical practice? This report briefly reviews some of the studies that may help address some of these questions.

Effects of trichostatin A(TSA) on the proliferation and apoptosis of hepatoma cell lines and the the replication of hepatitis B virus(HBV) / 重庆医科大学学报

Objective:To compare the effect of histone deacetylase inhititor trichostatin A(TSA) on the proliferation and apotosis of different hepatoma cell lines and to investigate the effect of TSA on hepatitis B virus(HBV) replication. Methods:Human hepatoma cell lines HepG2,HepG2.2.15,QGY7701 and normal liver cell line L02 were treated with TSA, the effects on proliferation and apoptosis were examined by MTT assay and agarose gel electrophoresis of DNA; The viral proteins of hepatitis B surface antigen(HBsAg)and e antigen(HBeAg) in culture medium were measured using the Abbott Microparticle Enzyme Immunoassay kits;The medium HBV DNA levels were quantified using HBV real-time PCR kit. Results:(a)TSA treatment repressed proliferation and induced apoptosis in hepatoma cell lines;(b)The normal repressed proliferation and induced apoptosis in hepatoma cell lines;(b) The normal liver cell line L02 was not sensitive to the treatment of TSA;(c)TSA stimulated HBV replication. Conclusions:TSA treatment could inhibit proliferation of different hepatoma lines,and the normal liver cell line L02 is not sensitive to TSA treatment. However,TSA stimulates HBV replication. Therefore,our results suggest that TSA might be a good chemotherapic candidate for hepatocellular carcinoma patients without HBV infection but may not be suited to treat hepatocellular cancer patients with HBV infection.

Study on HBV Gene Replication and Expression of Experimental Hepatitis B Model Using Baculovirus Gene Delivery System

PURPOSE: The lack of reliable in vitro infection systems or convenient animal models has hindered the progress of hepatitis B virus (HBV) research and the development of new treatment options. We established an in vitro model of hepatitis B, using recombinant HBV encoding baculovirus, which provided HBV replication and antigens expression in HepG2 cells. The objectives of this study were to characterize the magnitude of HBV expression and the level of replication obtainable in HepG2 cells, to establish the optimum infection and culture conditions of HBV expression and replication. METHODS: Replication of a competent HBV genome encoding the baculovirus, RC-HBV-Bac, was generated for delivering the HBV genome to HepG2 cells. HBV replication and antigens expression were determined in relation to the infection and culture conditions. RESULTS: In RC-HBV-Bac infected HepG2 cells, HBsAg, HBeAg and HBcAg were expressed in the cytoplasm and nuclei, and secreted into the medium. HBV replication was evidenced by the presence of a replication complex and covalently closed circular (ccc) DNA in the cytoplasmic fraction of infected cells. The level of HBV expression was directly proportional to the multiplication of RC-HBV-Bac infection. Polyethylene glycol was able to enhance the infection efficiency of the baculovirus to HepG2 cells. High levels of HBV replication were achieved under culture conditions supplemented with dimethyl sulfoxide and a low serum concentration. CONCLUSION: This in vitro model of hepatitis B, generated by baculovirus gene delivery, represents a simple and flexible system for the study of HBV replication and drug testing.

Construction of double-copy and x gene deleted hepatitis B virus DNA expression plasmid and cells transfection study / 第二军医大学学报

Objective:To construct double copy and x gene deleted HBV expression plasmid and study its expression in Hep3B cell line. Methods:The double copy HBV DNA ( adr Ⅰ) was used to inactivate HBV x gene by inserting mutation and gene recombination. The inserted 55 bp DNA sequence was synthesized artificially; the insertion point was ApaL Ⅰ of x gene area. After recombination, an x gene defected HBV plasmid containing single P, S and C gene was constructed,which can express in mammalian cell line. Another plasmid carrying double copy HBV DNA with normal x gene was constructed as contrast. Both were used to transfect Hep3B cells. Then the cells were screened by G418 and HBV virus in culture medium were isolated and detected by fluorescence quantitative PCR. Results: Plasmids pcDNA3 KN F1F2 and pcDNA3 ES HBV2 were constructed successfully. After cell transfection, the HBV DNA was highly expressed with both plasmids on the 3 rd, 6 th,14th day. Conclusion: The plasmids constructed can express in Hep3B cell line and cause HBV replication; x gene defected HBV gene has no effect on HBV replication in Hep3B cell line.

Inhibition of HBV replication by antisense oligodeoxyribonucleotides in HepG2 cells transfected with a cloned HBV DNA

The effect of antisense oligodeoxyribonucleotides(oligo[dN]s) on hepatitis B virus(HBV) replication in HepG2 cells harboring a cloned HBV genome was examined. Antisense oligo(dN)s directed at translational initiation sites of S, pre C and P genes of HBV were treated to the cells and the amount of HBsAg and HBV DNA content were measured 72 hours after the treatment. HBsAg expressions in HepG2 cells harboring the HBV genome were inhibited 68%, 53%, and 46% by the treatment with antisense oligo[dN] directed at S, pre C, and P gene loci, respectively, and HBV DNA content in the cells was also reduced by the treatment of each antisense oligo[dN]. The doubling times of the cultured cells treated with 25 micrograms, 50 micrograms, and 100 micrograms of antisense oligo[dN]/ml medium were 43.3, 62.1, and 93.0 hours, respectively, compared with 37.5 hours of the untreated control cells. Cellular DNA synthesis was inhibited by the treatment with 100 micrograms/ml of antisense oligo [dN], however, no significant effect was observed by the treatment with 50 micrograms or less of antisense oligo[dN]/ml. These results suggested that antisense oligo[dN]s specific to the translational initiation sites of S, pre C, and P genes of HBV may have therapeutic potential for the suppression of HBV propagation in chronic HBV infected patients.

The Clinical Study for Pre-S2 Antigen and Antibody in Serum Related to HBV Replication and Liver In jury / 昆明医科大学学报

0.05). The patients whose Pre-S2 antigen and antibody are positive in the serum are mainly with chronic hepatitis B (P