单链抗体已用于抗乙肝病毒(hepatitis B virus,HBV)的研究,目前已研制出作用于各种靶点,如HBV表面抗原pre-S1、核心蛋白(hepatitis B virus core antigen,HBc)、DNA聚合酶及X蛋白的多种单链抗体。单链抗体对偶联的分子具有靶向定位作用,因此,对抗原的亲和性大小、对靶细胞内化(Internalization)的强弱及其自身结构的稳定性是影响单链抗体应用的主要因素。
BACKGROUND: It has been demonstrated that only a minority of patients with hepatitis B e antigen (HBeAg) negative chronic hepatitis B (CHB) obtain a sustained response after either interferon (IFN) or nucleos (t)ide analogue monotherapy. Therefore, combination therapy of drugs with synergistic antiviral effects was proposed to have a sustained response in these patients. We compared the effect and safety of lamivudine monotherapy and its combination with IFN including conventional interferon (CON-IFN) and pegylated interferon (PEG-IFN) for HBeAg-negative CHB patients. DATA SOURCES: A group of three independent reviewers identified 9 eligible randomized controlled trials through electronic searches (MEDLINE, OVID, EMBASE, the Cochrane Library Clinical Trials Registry, and the Chinese Medical Database), manual searches, and contact with experts. Sustained virological and biochemical responses were defined as primary efficacy measures. We performed quantitative meta-analyses to assess differences between CON-IFN plus lamivudine combination and lamivudine monotherapy groups. RESULTS: No greater sustained virological and biochemical rates were found in patients receiving CON-IFN/lamivudine combination therapy [29.1% vs. 26.7%, odds ratio (OR)=0.98, 95% confidence interval (CI) 0.65-1.50, P=0.94, and 41.8% vs. 40.3%, OR=1.13, 95% CI 0.78-1.65, P=0.51, respectively],though a reduced YMDD mutation rate was achieved in the combination group [8.39% vs. 30.0%, OR=0.16, 95% CI 0.076-0.33, P<0.001]. However, data from one PEG-IFN trial showed greater sustained virological and biochemical rates in patients receiving combination therapy [response rate 19.5% vs. 6.6%, OR=3.42, 95% CI 1.71-6.84, P<0.001 and 60.0% vs. 44.2%, OR=1.88, 95% CI 1.23-2.85, P=0.003, respectively]. CONCLUSIONS: Addition of CON-IFN to lamivudine did not improve treatment efficacy but suppressed YMDD mutation by lamivudine. Combination of PEG-IFN and lamivudine might increase the sustained response, and further clinical trials are needed for confirmation.
Objective:To explore the mechanisms of fulminant hepatitis(FH) in the early stages,and to determine the critical pathways in its initiation and progression.Methods:Twelve BALB/c mice were divided into four groups:one group left as negative control and sacrificed immediately after injection of phosphate-buffered saline(PBS),and another three groups with concanavalin A(Con A) administration sacrificed at 1,3,and 6 h after injection.Affymetrix GeneChip Mouse 430 2.0 Array was employed to evaluate the expression profile of each of the 12 samples.Further analysis was done on the microarray data to extract the genes that were differentially expressed.Enrichment analysis was carried out to determine relevant pathways within which regulated genes were significantly enriched.Results:A total of 393,8354 and 11 344 differentially expressed genes were found,respectively,at three time points.During 0-1 h and 1-3 h,most of the pathways enriched with regulated genes were related to immune response and inflammation,among which Toll-like receptor(TLR) signaling and mitogen-activated protein kinase(MAPK) signaling appeared during both phases,while cytokine-cytokine receptor interaction,apoptosis,T cell receptor signaling,and natural killer(NK) cell-mediated cytotoxicity pathways emerged during the second phase.Pathways found to be significant during 3-6 h were mostly related to metabolic processes.Conclusion:The TLR signaling pathway dominates the early responses of Con A-induced FH in mice.It stimulates the production of type I cytokines,therefore recruiting and activating T/NK cells.Activated T/NK cells exert their cytotoxicity on hepatocytes through inducing death receptorintermediated apoptosis,resulting in liver injury.
Qing-yi CAO Feng CHEN Jie LI Shan-shan WU Jing WANG Zhi CHEN
