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Order Martellivirales: Virgaviridae
Published in Paul Pumpens, Peter Pushko, Philippe Le Mercier, Virus-Like Particles, 2022
Paul Pumpens, Peter Pushko, Philippe Le Mercier
Smith et al. (2007) introduced the TMV OAS into the RNA genome of Semliki Forest virus (SFV) and generated an SFV expression vector that was efficiently packaged in vitro by the TMV coat purified from wild-type or chimeric virions. The SFV vector was lacking the SFV structural proteins but expressing the beta-galactosidase (β-gal) reporter gene. The vector encapsidation significantly improved the humoral and cellular immune responses in mice. Furthermore, reassembly with recombinant TMV coats permitted the display of peptide epitopes on the capsid surface as either genetic fusions or through chemical conjugation to complement the immunoreactivity of the encapsidated RNA genetic payload. This SFV vector/TMV coat system provided therefore an original packaging and delivery model, as reviewed early by McCormick and Palmer (2008).
Human Monoclonal Antibodies and Immune Modulation in Viral Hepatitis, Schistosomiasis, and HTLV Infection
Published in Thomas F. Kresina, Immune Modulating Agents, 2020
Thomas F. Kresina, Garry A. Neil, Steven K. H. Foung
Disease association studies of these viruses have been hindered by the need for multiple assays to confirm and differentiate infection between these viruses. To approach this problem, our laboratory isolated and characterized a unique HTLV-I epitope with the human monoclonal antibody, 0.5 alpha [43–45]. The lambda gtll expression vector system was used to generate an epitope library of HTLV-I envelope gene-encoded antigenic determinants. In this system, recombinant peptides are expressed as fusion proteins within the native bacterial beta-galactosidase molecule. By immunoscreening with the 0.5 alpha antibody, multiple recombinant epitopes were isolated. One of these recombinant proteins, designated MTA-1, has been identified with HTLV-1 infection but not with HTLV-II infection or controls.
Participation of Cytokines and Growth Factors in Biliary Epithelial Proliferation and Mito-Inhibition during Ductular Reactions
Published in Gianfranco Alpini, Domenico Alvaro, Marco Marzioni, Gene LeSage, Nicholas LaRusso, The Pathophysiology of Biliary Epithelia, 2020
Anthony J. Demetris, J.G. Lunz, Vladimir Subbotin, Tong Wu, Isao Nozaki, Sarah Contrucci, Xia Yin
Recently, we have achieved significant progress in BEC transfection using the common bile duct to deliver a nonviral vector consisting of plasmid DNA complexed with polymers. Using these DNA/polymer complexes for gene delivery,185 we have been able to achieve luciferase reporter gene expression levels in the hundreds of nanograms per gram of liver tissue. In addition, using a beta-galactosidase reporter gene with the same delivery system and conditions, we found that the expressing cells appeared to be exclusively BEC (Fig. 7). These results are especially encouraging given the fact that BEC comprise only about 5–6% of liver cells,28 suggesting that high level BEC transfection using nonviral complexes is possible. Similar BEC-specific transfection results were obtained using a mouse BDL model (Fig. 7).
Obesity and Related Metabolic Biomarkers and Its Association with Serum Levels of Estrogen in Pre-pubertal Chilean Girls
Published in Endocrine Research, 2020
Diana Carolina Mesa Valencia, Verónica Mericq, Camila Corvalán, Ana Pereira
Measurement of ultrasensitive estrogens was performed by an ultrasensitive recombinant cell bioassay (RCBA). This technique uses a strain of Saccharomy cescerevisiae, which is transformed with two plasmids. One plasmid is the DNA of the complementary human estrogen receptor, and the other plasmid includes an estrogen response element upstream of the beta-galactosidase structural gene. Yeast was incubated for 8 hours with either extracts of 0.8 ml of standard serum or estradiol. Beta-galactosidase activity was measured with ortho-nitrophenol galactopyranoside as a substrate. A standard linear interpolation curve was used to estimate the estradiol equivalent units.16 The sensitivity of the bioassay was 0.02–0.2 pg/ml (0.07 to 0.7 pmol/l). The intra- and interassay coefficients of variation of 0.2 pg/ml (0.7 pmol/l) were 10–50%.17
Vaccinia-based oncolytic immunotherapy Pexastimogene Devacirepvec in patients with advanced hepatocellular carcinoma after sorafenib failure: a randomized multicenter Phase IIb trial (TRAVERSE)
Published in OncoImmunology, 2019
M. Moehler, J. Heo, H.C. Lee, W.Y. Tak, Y. Chao, S.W. Paik, H.J. Yim, K.S. Byun, A. Baron, G. Ungerechts, D. Jonker, L. Ruo, M. Cho, A. Kaubisch, H. Wege, P. Merle, O. Ebert, F. Habersetzer, J.F. Blanc, Olivier Rosmorduc, R. Lencioni, R. Patt, A.M. Leen, F. Foerster, M. Homerin, N. Stojkowitz, M. Lusky, J.M. Limacher, M. Hennequi, N. Gaspar, B. McFadden, N. De Silva, D. Shen, A. Pelusio, D.H. Kirn, C.J. Breitbach, J.M. Burke
Samples that tested positive in a screening step were tested in a confirmatory assay to identify true positives by assessing the specificity of the signal through competition with soluble beta-galactosidase. Positive signals were defined using a statistically determined, study-specific screening and confirmatory cutpoints calculated from background ECL signals of 110 patients' Day 1 predose samples. The screening cutpoint CP was set to a theoretical 5% false-positive rate (95% confidence Interval) and the confirmatory step CP was set to a theoretical 0.1% false-positive rate (99.9% confidence interval).48 To calculate the CP values, the data was transformed to Log (base 10) and assessed for normality using the Shapiro–Wilk test. After removal of outliers, a non-parametric analysis was used to calculate the CP for the screening step, whereas a parametric analysis was used to calculate the CP for the confirmatory step. The relative level of antibodies in samples was expressed as end point titer (EPT), defined as the reciprocal of the last dilution above the CP (set in this study at twice the Negative Control mean signal).
Taking a prebiotic approach to early immunomodulation for allergy prevention
Published in Expert Review of Clinical Immunology, 2018
Rachelle Pretorius, Susan L. Prescott, Debra J. Palmer
For industrial use, chicory is the principal source of inulin from which FOS are manufactured by partial enzymatic hydrolysis. Over recent years, the use of added FOS to manufactured food products such as cereal, bread, and dairy products marketed as functional foods has emerged. Functional foods, which are foods with added components to provide health benefit to the host, are now readily available for consumers to purchase at their local supermarket, pharmacy and health food shop. Additionally, capsule and powder form supplements containing prebiotics in the form of FOS and/or inulin are also available. The majority of the current prebiotic functional foods market is dominated by the addition of inulin and FOS to foods, but there is growing interest also in the use of lactose-derived prebiotics. GOS is manufactured from lactose using a naturally occurring enzyme beta-galactosidase [34]. In 2009, the US FDA declared GOS to be generally recognized as safe to be added as an ingredient in functional foods. To date, GOS is predominately added to infant formula (as discussed below) rather than a source of prebiotics within the maternal diet.