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Multitudinous broadly neutralizing antibodies (bNAbs) against HIV-1 have been developed as novel antiviral prophylactic and therapeutic agents. Combinations of bNAbs are generally even more effective than when they are applied individually, showing excellent neutralization coverage and limiting the emergence of escape mutants. In this study, we investigated the design and characterization of three trispecific antibodies that allow a single molecule to interact with independent HIV-1 envelope determinants—(1) the host receptor CD4, (2) the host co-receptor CCR5 and (3) distinct domains in the envelope glycoprotein of HIV-1—using an ELISA, an HIV-1 pseudovirus neutralization assay and in vivo antiviral experiments in humanized mice. We found that trispecific bNAbs and monovalent ones all had satisfactory binding activities against the corresponding antigens in the ELISA, exhibited higher potency and breadth than any previously described single bnAb in the HIV-1 pseudovirus neutralization assay and showed an excellent antiviral effect in vivo. The trispecific antibodies simultaneously recognize the host receptor CD4, host co-receptor CCR5 and HIV-1 envelope glycoprotein, which could mean they have promise as prophylactic and therapeutic agents against HIV-1. [ABSTRACT FROM AUTHOR]

The discovery of broadly neutralizing monoclonal antibodies against influenza viruses has raised hope for the successful development of new antiviral drugs. However, due to the speed and variety of mutations in influenza viruses, single‐component antibodies that recognize specific epitopes are susceptible to viral escape and have limited efficacy when administration is delayed. Hence, it is necessary to develop alternative strategies with better antiviral activity. Influenza B virus infection can cause severe illness in children and the elderly. Commonly used anti‐influenza drugs have low clinical efficacy against influenza B virus. In this study, we investigated the antiviral efficacy of combinations of representative monoclonal antibodies targeting different antigenic epitopes against the influenza B virus. We found that combinations of antibodies recognizing the hemagglutinin (HA) head and stem regions showed a stronger neutralizing activity than single antibodies and other antibody combinations in vitro. In addition, we found that pair‐wise combinations of antibodies recognizing the HA head region, HA stem region, and neuraminidase enzyme‐activated region showed superior antiviral activity than single antibodies in both mouse and ferret in vivo protection assays. Notably, these antibody combinations still displayed good antiviral efficacy when treatment was delayed. Mechanistic studies further revealed that combining antibodies recognizing different epitope regions resulted in extremely strong antibody‐dependent cell‐mediated cytotoxicity, which may partly explain their superior antiviral effects. Together, the findings of this study provide new avenues for the development of better antiviral drugs and vaccines against influenza viruses. [ABSTRACT FROM AUTHOR]

BACKGROUND Heavy metal pollution has become one of the most serious environmental problems. Novel approaches are needed for removal of heavy metal from water. Copper, a familiar heavy metal, has attracted much attention for its remarkable toxic domino offect at elevated concentrations. RESULTS A novel ion imprinted approach combined with microfluidic technology was explored. Cu2+ was taken as ionic template and chitosan was used as carrier material. Chemical crosslinking was applied in the formation of imprinted sign. A selective biosorbent of ion-imprinted microspheres ( IIMS) with uniform size, regular shape and high performance for Cu2+ had been prepared. The SEM, FTIR, EDS, XPS were employed to detect their distinct features. IIMS showed much higher adsorption capacity ( qm=81.97 mg g−1) than those non-imprinted chitosan microspheres ( CSMS). The adsorption isotherm fitted the Langmuir equation while thermodynamic adsorption results were considered strong proof of an adsorption exothermal process. IIMS exhibited excellent selectivity for Cu2+ when competitive metal ions and Cu2+ co-existed together, which profited from the specific spaces of Cu2+ template left after crosslinking and desorption. Results confirmed that chemical adsorption was dominant and amino played an important role in adsorption process. CONCLUSION IIMS showed high adsorption capacity and excellent selectivity for Cu2+. Combining microfluidic technology with an ion-imprinted method proved to be a promising process for preparing selective materials. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Human adenovirus (HAdV) infects the respiratory system, thus posing a threat to health. However, immunodiagnostic reagents for human adenovirus are limited. This study aimed to develop efficient diagnostic reagents based on monoclonal antibodies for diagnosing various human adenovirus infections. Evolutionary and homology analyses of various human adenoviral antigen genes revealed highly conserved antigenic fragments. The prokaryotic expression system was applied to recombinant penton, hexon, and IVa2 conserved fragments of adenovirus, which were injected into BALB/c mice to prepare human adenovirus-specific monoclonal antibodies. Enzyme-linked immunosorbent assay (ELISA), indirect immunofluorescence assay (IFA), and Western blotting were used to determine the immune specificity of the monoclonal antibodies. Indirect ELISA showed that monoclonal antibodies 1F10, 8D3, 4A1, and 9B2 were specifically bound to HAdV-3 and HAdV-55 and revealed high sensitivity and low detection limits for various human adenoviruses. Western blotting showed that 1F10 and 8D3 specifically recognized various human adenovirus types, including HAdV-1, HAdV-2, HAdV-3, HAdV-4, HAdV-5, HAdV-7, HAdV-21, and HAdV-55, and 4A1 specifically recognized HAdV-1, HAdV-2, HAdV-3, HAdV-5, HAdV-7, HAdV-21, and HAdV-55. IFAs showed that 1F10, 8D3, and 4A1 exhibited highly selective localization to A549 cells infected with HAdV-3 and HAdV-55. Finally, two antibody pairs that could detect hexon antigens HAdV-3 and HAdV-55 at low concentrations were developed. The monoclonal antibodies developed in this study show potential for detecting human adenoviruses., Importance: In this study, we selected the three most conserved antigenic fragments of human adenovirus to prepare a murine monoclonal antibody for the first time, and human adenovirus antigenic fragments with heretofore unheard of degrees of conservatism were isolated. The three monoclonal antibodies with the ability to recognize human respiratory adenovirus over a broad spectrum were screened by hybridoma and monoclonal antibody preparation. Human adenovirus infections are serious; however, therapeutic drugs and diagnostic reagents are scarce. Thus, to reduce the serious consequences of human viral infections and adenovirus pneumonitis, early diagnosis of infection is required. The present study provides three monoclonal antibodies capable of recognizing a wide range of human adenoviruses, thereby offering guidance for subsequent research and development., Competing Interests: The authors declare no conflict of interest.