Characterization of VRC01, a potent and broadly neutralizing anti-HIV mAb, produced in transiently and stably transformed tobacco

The proposed clinical trial in Africa of VRC01, a potent broadly neutralizing antibody (bNAb) capable of neutralizing 91% of known HIV-1 isolates, raises concerns about testing a treatment which will be too expensive to be accessible by the most important target population, the poor in under-developed regions such as sub-Saharan Africa. Here, we report the expression of VRC01 in plants as an economic alternative to conventional mammalian-cell-based production platforms. The heavy and light chain genes of VRC01 were cloned onto a single vector, pTRAk.2, which was transformed into Nicotiana benthamiana or Nicotiana tabacum using transient and stable expression production systems respectively. VRC01 has been successfully expressed transiently in plants with expression level of approximately 80 mg antibody/kg; stable transgenic lines expressing up to 100 mg antibody/kg were also obtained. Plant-produced VRC01 from both systems showed a largely homogeneous N-glycosylation profile with a single dominant glycoform. The binding kinetics to gp120 IIIB (approximately 1 nM), neutralization of HIV-1 BaL or a panel of 10 VRC01-sensitive HIV-1 Env pseudoviruses of VRC01 produced in transient and stable plants were also consistent with VRC01 from HEK cells

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Proceedings of EMEA 2000 in Kanazaw

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Proceedings of EMEA 2001 in Beijing, 19-20 June 2001 in Beijing (China

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Proceedings of EMEA 2001 in Kanazawa, 25-27 September 2001 in Kanazawa (Japan

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Proceedings of EMEA 1999 in Kanazawa, 20-21 October 1999 in Kanazawa (Japan

Experimental and Quantum Chemical Studies on the Corrosion Inhibition Potentials of Xylopia aethiopica extracts

Root and root bark extracts of Xylopia aethiopica (XE) have been evaluated as corrosion inhibitors for mild steel in aerated 0.1 M HCl and H2SO4 solutions by gravimetric method. The inhibition efficiency increases with increase in inhibitor concentrations. Adsorption mechanisms for the adsorptions of XE extracts’ molecules were predicted using the following adsorption isotherms (Langmuir, Freundlich, Temkin and El-Awady) by linear regression. With the aid of Chi-square (X2) statistic, the best fitted adsorption isotherms were selected. Physisorption mechanisms have been proposed for the extracts in the studied acidic media.  Quantum chemical calculations gave some electronic properties of the molecules of XE extracts so as to ascertain any correlation(s) between the corrosion inhibition and molecular structures. Keywords: Quantum Chemical calculation, Xylopia aethiopica, corrosion inhibitio

Blood Cytokines as Biomarkers of In Vivo Toxicity in Preclinical Safety Assessment: Considerations for Their Use

In the drive to develop drugs with well-characterized and clinically monitorable safety profiles, there is incentive to expand the repertoire of safety biomarkers for toxicities without routine markers or premonitory detection. Biomarkers in blood are pursued because of specimen accessibility, opportunity for serial monitoring, quantitative measurement, and the availability of assay platforms. Cytokines, chemokines, and growth factors (here referred to collectively as cytokines) show robust modulation in proximal events of inflammation, immune response, and repair. These are key general processes in many toxicities; therefore, cytokines are commonly identified during biomarker discovery studies. In addition, multiplexed cytokine immunoassays are easily applied to biomarker discovery and routine toxicity studies to measure blood cytokines. However, cytokines pose several challenges as safety biomarkers because of a short serum half-life; low to undetectable baseline levels; lack of tissue-specific or toxicity-specific expression; complexities related to cytokine expression with multiorgan involvement; and species, strain, and interindividual differences. Additional challenges to their application are caused by analytical, methodological, and study design–related variables. A final consideration is the strength of the relationship between changes in cytokine levels and the development of phenotypic or functional manifestations of toxicity. These factors should inform the integrated judgment-based qualification of novel biomarkers in preclinical, and potentially clinical, risk assessment. The dearth of robust, predictive cytokine biomarkers for specific toxicities is an indication of the significant complexity of these challenges. This review will consider the current state of the science and recommendations for appropriate application of cytokines in preclinical safety assessment

Combining the in vivo comet and micronucleus assays: a practical approach to genotoxicity testing and data interpretation

Despite regulatory directives requiring the reduction of animal use in safety testing, recent modifications to genotoxicity testing guidelines now propose the use of two in vivo genotoxicity assays as a follow-up to an in vitro positive (International Conference on Harmonization Consensus Draft Guidance S2[R1] released March, 2008). To address both goals, the in vivo comet and micronucleus (MN) assays can be successfully combined into one informative study. Combining these two assays with such differences in sensitivity, endpoints measured and the type of data generated significantly improves upon the current standard capabilities for detecting genotoxicity without requiring additional animals. But to take full advantage of the benefits of incorporating the comet assay in safety testing, these same differences must be recognized and considered. Developed from over 15 years experience using the in vivo comet and MN assays in genotoxicity testing of chemicals and pharmaceuticals, this paper presents guidelines for the appropriate experimental design, dose selection and data interpretation for combined in vivo comet/MN assay studies. To illustrate the approach, data from combined assay studies are presented and discussed

Antimicrobial resistance monitoring and surveillance in the meat chain: A report from five countries in the European Union and European Economic Area

Background The emergence of antimicrobial resistance (AMR) in zoonotic foodborne pathogens (Salmonella, Campylobacter) and indicator microorganisms (E. coli, enterococci) is a major public health risk. Zoonotic bacteria, resistant to antimicrobials, are of special concern because they might compromise the effective treatment of infections in humans. Scope and approach In this review, the AMR monitoring and surveillance programmes in five selected countries within European Union (EU) and European Economic Area (EEA) are described. The sampling schemes, susceptibility testing for AMR identification, clinical breakpoints (clinical resistance) and epidemiological cut-off values (microbiological resistance) were considered to reflect on the most important variations between and within food-producing animal species, between countries, and to identify the most effective approach to tackle and manage the antimicrobial resistance in the food chain. Key findings and conclusions The science-based monitoring of AMR should encompass the whole food chain, supported with public health surveillance and should be conducted in accordance with ‘Zoonoses Directive’ (99/2003/EC). Such approach encompasses the integrated AMR monitoring in food animals, food and humans in the whole food (meat) chain continuum, e.g. pre-harvest (on-farm), harvest (in abattoir) and post-harvest (at retail). The information on AMR in critically important antimicrobials (CIA) for human medicine should be of particular importance

Differences in bioactivity between human insulin and insulin analogues approved for therapeutic use- compilation of reports from the past 20 years

In order to provide comprehensive information on the differences in bioactivity between human insulin and insulin analogues, published in vitro comparisons of human insulin and the rapid acting analogues insulin lispro (Humalog®), insulin aspart ( NovoRapid®), insulin glulisine (Apidra®), and the slow acting analogues insulin glargine (Lantus®), and insulin detemir (Levemir®) were gathered from the past 20 years (except for receptor binding studies). A total of 50 reports were retrieved, with great heterogeneity among study methodology. However, various differences in bioactivity compared to human insulin were obvious (e.g. differences in effects on metabolism, mitogenesis, apoptosis, intracellular signalling, thrombocyte function, protein degradation). Whether or not these differences have clinical bearings (and among which patient populations) remains to be determined