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Hepatitis B immunoglobulin (HBIG) has been routinely applied in the liver transplantation setting to block HBV reinfection of grafts. However, new monoclonal anti-HBV surface antibodies have been developed to replace HBIG. The epitopes of such monoclonal antibodies may affect the emergence of escape variants and deserve study.The conformational epitope of sLenvervimab, a surrogate form of Lenvervimab, which is a monoclonal anti-HBsAg antibody currently under phase 3 trial, was investigated by selecting escape mutants from a human liver chimeric mouse. HBV-infected chimeric mice treated with sLenvervimab monotherapy showed an initial decline in circulating HBsAg levels, followed by a quick rebound in 1 month. Sequencing of circulating or liver HBV DNA revealed emerging variants, with replacement of amino acid E164 or T140, two residues widely separated in HBsAg. E164 HBV variants strongly resisted sLenvervimab neutralization in cell culture infection, and the T140 variant moderately resisted sLenvervimab neutralization. Natural HBV variants with amino-acid replacements adjacent to E164 were constructed and examined for sLenvervimab neutralization effects. Variants with K160 replacement also resisted neutralization. These data revealed the conformational epitope of sLenvervimab.Selection of antibody-escape HBV variants in human chimeric mice works efficiently. Analysis of such emerging variants helps to identify anchor amino-acid residues of the conformational epitope that are difficult to discover by conventional approaches.

Background Hepatitis B virus (HBV) persistently infected about 250 million people worldwide, and a curative treatment remains an unmet medical need. Among many approaches to treat chronic hepatitis B (CHB), therapeutic vaccines have been developed for two decades, but none have yielded promising results in clinical trials. Therefore, dissection of HBV clearance mechanisms during therapeutic vaccination in appropriate models, which could give rise to new curative therapies, is urgently needed. Growing evidence indicates that prolonged and intensive exposure of antigen-specific T cells to viral antigens is a major cause of T cell exhaustion, and decreases anti-HBV immunity efficacy of therapeutic vaccination. HBV X protein (HBx) is expressed at low levels, and the understanding of its immunogenicity and potential in therapeutic CHB vaccines is limited. Methods HBV genome sequences from CHB patients were cloned into a pAAV plasmid backbone and transfected into immunocompetent mouse hepatocytes through hydrodynamic injection. Mice carrying > 500 IU/mL serum HBV surface antigen (HBs) for more than 4 weeks were considered HBV carriers mimicking human CHB and received 3 doses of weekly HBx vaccine by subcutaneous immunization. Serum HBV clearance was evaluated by monitoring serum HBs and HBV-DNA titers. Residual HBV in the liver was evaluated by western blotting for HBV core antigen. The splenic antigen-specific T cell response was quantified by a 15-mer overlapping peptide-stimulated interferon-γ enzyme-linked immunospot assay. Blood and hepatic immune cells were quantified by flow cytometric analysis. Results Our HBx-based vaccine induced systemic HBx-specific CD4+ and CD8+ T cell responses in HBV carrier mice and demonstrated significant HBs and HBV-DNA elimination. The protective effect persisted for at least 30 days without additional booster immunization. Different infiltrating myeloid cell subsets, each with distinctive roles during immune-mediated HBV clearance, were found in the liver of vaccinated mice. During vaccine therapy, inflammatory monocyte depletion resulted in sustained HBV clearance inhibition, whereas phagocytic monocyte-derived macrophage and Kupffer cell elimination resulted in only transient inhibition of vaccine-induced HBV clearance. Conclusions We report the potential role of HBx as a major immunogen in an HBV therapeutic vaccine and the significance of a liver-infiltrating monocyte subset during hepatic viral clearance.

Additional file 1: Figure S1. Structures of RAP1-HBx, RAP1-E7 and pEt32a-HBx; Figure S2. HBV carrier mice do not produce protective anti-HBs antibodies; Figure S3. HBx vaccine immunization removes serum HBs in mice carrying different HBV genotypes; Figure S4. TVGV-HBx exhibits antiviral activity in a dose-dependent manner; Figure S5. Quantification of CpG-ODN-induced monocyte changes in the blood; Figure S6. The effect of gemcitabine or clodronate liposome treatment on the blood neutrophil frequency; Figure S7. Gemcitabine treatment does not inhibit systemic T cell immunity; Figure S8. Representative flow cytometry plots of liver myeloid cell subpopulations after TVGV-HBx vaccination and monocyte depletion; and Figure S9. Schematic diagram of monocyte preconditioning of the liver immune environment and its impact on HBx therapeutic vaccine efficacy.

Objective This study aimed to investigate the therapeutic potential of monoclonal antibody (mAb) against HBV as a novel treatment approach to chronic hepatitis B (CHB) in mouse models. Methods Therapeutic effects of mAbs against various epitopes on viral surface protein were evaluated in mice mimicking persistent HBV infection. The immunological mechanisms of mAb-mediated viral clearance were systematically investigated. Results Among 11 tested mAbs, a novel mAb E6F6 exhibited the most striking therapeutic effects in several HBV-persistent mice. Single-dose administration of E6F6 could profoundly suppress the levels of hepatitis B surface antigen (HBsAg) and HBV DNA for several weeks in HBV-transgenic mice. E6F6 regimen efficiently prevented initial HBV infection, and reduced viral dissemination from infected hepatocytes in human-liver-chimeric mice. E6F6-based immunotherapy facilitated the restoration of anti-HBV T-cell response in hydrodynamic injection (HDI)-based HBV carrier mice. Immunological analyses suggested that the Fcγ receptor-dependent phagocytosis plays a predominant role in E6F6-mediated viral suppression. Molecular analyses suggested that E6F6 recognises an evolutionarily conserved epitope (GPCK(R)TCT) and only forms a smaller antibody–viral particle immune complex with limited interparticle crosslinking when it binds to viral particles. This unique binding characteristic of E6F6 to HBV was possibly associated with its effective in vivo opsonophagocytosis for viral clearance. Conclusions These results provided new insight into understanding the therapeutic role and mechanism of antibody against persistent viral infection. The E6F6-like mAbs may provide a novel immunotherapeutic agent against human chronic HBV infection.

Chronic hepatitis B is a global health issue, as WHO estimates about 240 millions in the world. Without antiviral therapies, a quarter of the HBV carriers will eventually succumb to cirrhosis or hepatocellular carcinoma (Fattovich et al. 2004; Di Bisceglie 2009; Beasley 1988; Liaw et al. 1988). Active therapies have been developed, such as pegylated interferon and antiviral nucleos(t)ide analogs, in the last 20 years (Belloni et al. 2012; Papatheodoridis et al. 2002; Lau et al. 2005). Despite of an effective control of HBV replication by long-term NA treatments, the success of eliminating intrahepatic HBV or infected hepatocytes remains low (about 1–10% of treated patients). A search for novel, curative antiviral therapies has been actively taken up in many institutes. Practically, current NA therapies effectively eliminate extracellular virions, and so the next step will be to eliminate the intracellular viral RNAs, viral proteins, or eventually viral DNAs. The theme has become a more and more important medical task, especially after the advent of highly effective direct antiviral agents curing essentially hepatitis C. Therefore, there are many excellent reviews on the HBV life cycle or immunology that point out or summarize possible targets for future antiviral development (Lanford et al. 2013; Isogawa et al. 2005; Ma et al. 2015; Tang et al. 2016; Petersen et al. 2016). This chapter will skip these overlapping parts but only describe certain exploratory experiments toward novel targets ongoing. The main approach is to develop antiviral immunotherapies which can eradicate intrahepatic HBV DNAs or the HBV-infected hepatocytes in the near future.

Estrogen has been postulated to contribute to the development and progression of lung cancer. We examined the epidemiologic evidence, explored the characteristics of estrogen receptors (ER) in lung adenocarcinoma, and investigated the effect of estrogen on lung cancer cell migration, including the signaling pathway involved. For epidemiologic evidence, a total of 1434 consecutive non-small cell lung cancer patients who underwent standardized staging and homogenous treatment were prospectively enrolled from January 2002 to December 2008, and followed until December 2012. The possible prognostic factors to be analyzed included stage, age, gender, menopausal status, smoking history and histology. For laboratory study, lung cancer cell lines A549 and PE089 and malignant pleural effusions from the patients with lung adenocarcinoma were used. We found that the premenopausal patients had more advanced disease and a shorter survival among the never-smoking female patients with lung adenocarcinoma. ERβ was the predominant ER in the lung cancer cell lines. We proposed a different pathway that estrogen upregulated the expression of osteopontin and then promoted cell migration through αvβ3 integrin binding and activated MEK-ERK signaling pathway, which is a common downstream pathway with epidermal growth factor receptor (EGFR) activation. An additive effect of ER antagonists and EGFR antagonists on the inhibition of cell migration was also noted. Our results suggest that estrogen adversely affects the prognosis of patients with lung adenocarcinoma. Osteopontin contributed to the cross-talk between ER and EGFR signaling pathways. Estrogen, with its receptor, has the potential to be a prognosticator and a therapeutic target in lung cancer.

Environmental awareness, green directives, liberal return policies, and recycling of materials are globally accepted by industry and the general public as an integral part of the product life cycle. Reverse logistics reflects the acceptance of new policies by analyzing the processes associated with the flow of products, components and materials from end users to re-users consisting of second markets and remanufacturing. The components may be widely dispersed during reverse logistics. Radio frequency identification (RFID) complying with the EPCglobal (2004) Network architecture, i.e., a hardware- and software-integrated cross-platform IT framework, is adopted to better enable data collection and transmission in reverse logistic management. This research develops a hybrid qualitative and quantitative approach, using fuzzy cognitive maps and genetic algorithms, to model and evaluate the performance of RFID-enabled reverse logistic operations (The framework revisited here was published as ''Using fuzzy cognitive map for evaluation of RFID-based reverse logistics services'', Proceedings of the 2009 international conference on systems, man, and cybernetics (Paper No. 741), October 11-14, 2009, San Antonio, Texas, USA.). Fuzzy cognitive maps provide an advantage to linguistically express the causal relationships between reverse logistic parameters. Inference analysis using genetic algorithms contributes to the performance forecasting and decision support for improving reverse logistic efficiency.

Insertion of silver tetracyanoquinodimethane (AgTCNQ) complexes into a Langmuir-Blodgett matrix is achieved by diffusion of silver nitrate into N -docosylpyridinium-TCNQ complex multilayers, followed by reaction of silver cations with the TCNQ species in situ . Formation of a new compound in the films causes a change in optical absorption related to charge transfer of TCNQ complexes and a chemical shift in binding energy for the core levels of silver and nitrogen incorporated in the TCNQ radical anion as well as an increase in thickness per layer by 2.5 A of the films. The reaction rate is influenced by film reactivity, but is independent of the bulk solution concentration of silver nitrate, probably because of the limited diffusion of the molecules in compact films.

The geometry of poly(2,5-furanlene vinylene) (PFV) was optimized by the CNDO/2 method. The electronic structure of PFV has been studied by tight-binding extended Huckle calculation through interpretation of projected DOS plots, differential overlap populations and LCAO coefficients of solid orbitals. The calculated valence band XPS spectrum is in good agreement with the experimental one obtained by valence band X-ray photoelectron spectroscopy in peak positions and intensities.

Reverse logistics research is used to analyze the processes associated with the flows of products, components and materials from end users to re-users in different industries. The products and components collected for reverse logistics are often widely dispersed, which complicates efforts to efficiently collect, reuse and reassemble used components for reprocessing and remanufacturing. Therefore, Radio Frequency Identification (RFID) technology combined with the EPCglobal network architecture is applied to facilitate product and component data collection and data transmission. This research proposes a decision support model that integrates fuzzy cognitive maps trained using a genetic algorithm. The advantage of using fuzzy cognitive maps is that the model and the relationships among nodes (states) can be linguistically expressed both quantitatively and qualitatively. Furthermore, to diminish the subjective effects of the weights, the genetic algorithm is applied. The model and the information system integrate the EPCglobal network architecture with the RFID technology. Finally, a case concerning automobile repair reverse logistics is used to demonstrate the usefulness of the approach.

The photoelectron emission from thin films of lightly doped polythiophene was investigated in the ultraviolet and vacuum ultraviolet spectral region. Absolute quantum yields rising from 4*10-6 at 5 eV to 3*10-3 at 10.5 eV were measured. The photoemission threshold was determined to be Eth=5.06+or-0.05 eV. The films were produced electrochemically with perchlorate ions as the dopant.

Campus navigation and parking assistant system (CaNPAs) is a driver and pedestrian guidance and parking information system designed for use on university, company and government campuses and building complexes. The system communicates with its user via simple portable devices and can provide each user with voice navigation directions along the way to the user's destination. It also can provide information on available parking spaces at and around the user's destination and along the selected route. The system is designed to be low cost, easy to deploy and maintain. This paper describes its architecture and implementation.

The author regrets as there were some mistakes in the below references in the original paper. The corrected references of these are as below: R. Luis, S. Rossitza and L.S. Jose, Modeling IT projects success with fuzzy cognitive maps, Expert Systems with Applications 32 (2) (2007), pp. 543–559. and B. Salvador and L.S. Jose, Benchmarking main activation functions in fuzzy cognitive maps, Expert Systems with Applications 36 (3) (2009), pp. 5221–5229. The correct references are: Rodriguez-Repiso, L., Setchi, R., & Salmeron, J. L. (2007). Modeling IT projects success with fuzzy cognitive maps. Expert Systems with Applications, 32(2), 543–559. and Bueno, S., & Salmeron, J. L. (2009). Benchmarking main activation functions in fuzzy cognitive maps. Expert Systems with Applications, 36(3), 5221–5229.