72 research outputs found

    Extension as a Multilevel Bridging Organization: Supporting Networked Environmental Governance

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    Governmental and nongovernmental actors at different spatial and jurisdictional levels have information that can benefit natural resources management; however, barriers in communication and organizational culture often prevent information sharing and joint endeavors. Bridging entities, such as task forces or working groups, bring together potential stakeholders to pool expertise and stimulate shared learning. Using a network survey, interview data, and meeting minutes, we constructed a case study of task forces convened to stimulate management of the emerald ash borer, an invasive wood-boring beetle. We found that coordinated action among university and county Extension catalyzed bridging through visionary program design and network positioning

    Engineering CHO cells for the production of Hard-To-Produce proteins

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    Over the past decades, the CHO cell has become increasingly popular as the favorite host cell line for the production of protein based therapeutic drugs. In comparison with the popularity of the CHO cells and the frequent use of these cells to produce a large part of the bestselling blockbuster drugs, less intensive efforts have been done to understand the machinery used by the CHO cells during growth and production. The main approach has (broadly speaking) been to approach the CHO cell as a “black box” where one could insert the gene of interest, perform a number of amplifying steps, like gene amplification, selection for stable clones, intense screening for stably expressing high producers, and massive efforts to optimize a specific bioprocess for the selected cell line(s). Since 2013, the Novo Nordisk Foundation Center for Biosustainablity at the Technical University of Denmark has embarked on a large CHO program to open up the “black box”, to get a deeper understanding of the available machinery inside the protein producing “cell factory” that is CHO cells. We are using this understanding to engineer new CHO cell lines having significantly improved features for the production of therapeutic proteins. We are not only doing this by improving the titer, quality, downstream processing and speed of development for already well-known proteins (e.g. Ab), but also for the production of therapeutic proteins that cannot be produced in CHO cells today, due low titer, wrong post translational modifications, and/or low activity. By combining the competences embedded in the CHO program, we are able to exploit the combination of genome scale modelling, high throughput protein expression, deep understanding of both the glycosylation machinery as well as the secretory and metabolic pathways involved in the expression of secreted proteins. This knowledge is being used as input to a high throughput CHO cell line engineering pipeline, able to engineer up to 10 cell lines and 25 gene targets in parallel. This has resulted in a large number of new CHO cell lines enabling the production of proteins with specific tailor-made glycoprofiles, higher quality, less degradation, improved bioprocess, higher viable cell density and better cell viability. We have made a cell lines where we have removed a number of naturally expressed host cell proteins (HCP) from CHO, which has resulted in higher titer and higher VCD, cell lines showing increased resistance to viral infections, cell lines displaying homogenous glycoprofiles, reduced degradation, and drastically changed cell lines that does not produce lactate. These features are currently being combined to engineer CHO cells able to produce proteins that have not been possible to produce with adequate product quality and titer using CHO cells to date

    Elimination of the Warburg effect in Chinese hamster ovary (CHO) cells improves cell phenotype as a protein production platform

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    Lactate is a common metabolite and is central to many important processes. One of its more prominent roles is in the Warburg effect, in which cancer cells exhibit high rates of glycolytic flux followed by secretion of lactate, even in the presence of oxygen. This fermentation of pyruvate to lactate via lactate dehydrogenase (Ldh) accompanies increased proliferation of cancer cells and several other types of rapidly proliferating cell types in immune cell activation and embryonic development. Aerobic glycolysis is also prominent in biotherapeutic protein production, where mammalian production cells often secrete high levels of lactate. The accumulation of lactate is deleterious for cell growth, viability, product formation, and quality, both directly via acidification of the media and indirectly through base addition to control culture pH. Despite a clear genetic target, efforts to eliminate lactate secretion via knockout of Ldh(s) in mammalian cells have been unsuccessful, pointing to the essentiality of Ldh mediated NAD regeneration. A wide variety of approaches have been utilized to limit lactate accumulation in culture, including knockdown or inhibition of Ldh, replacement of glucose with alternate sugars, controlled feeding strategies, and many others, however none have proven successful in eliminating the Warburg effect. We report the elimination of the Warburg effect in a CHO cell line by using CRISPR/Cas9-based engineering to simultaneously knockout enzymes responsible for lactate production and ancillary regulators. The resulting cell lines remain proliferative while consuming significantly less glucose and can be used to generate protein producing lines using standard industrial processes. In a pH-controlled fedbatch process, the Warburg null cells require minimal base addition to maintain a stable pH, allowing an extended growth phase. The knockout strategy was also successfully applied to a CHO cell line producing Rituximab, again resulting in a prolonged growth phase. Additionally, protein production was maintained, while product quality was improved with increased glycan galactosylation. Thus, CHO cells without the capacity of Warburg metabolism may be useful for engineering production cell lines with enhanced bioproduction traits

    Dihydropyrimidine Dehydrogenase Testing prior to Treatment with 5-Fluorouracil, Capecitabine, and Tegafur: A Consensus Paper

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    Background: 5-Fluorouracil (FU) is one of the most commonly used cytostatic drugs in the systemic treatment of cancer. Treatment with FU may cause severe or life-threatening side effects and the treatment-related mortality rate is 0.2–1.0%. Summary: Among other risk factors associated with increased toxicity, a genetic deficiency in dihydropyrimidine dehydrogenase (DPD), an enzyme responsible for the metabolism of FU, is well known. This is due to variants in the DPD gene (DPYD). Up to 9% of European patients carry a DPD gene variant that decreases enzyme activity, and DPD is completely lacking in approximately 0.5% of patients. Here we describe the clinical and genetic background and summarize recommendations for the genetic testing and tailoring of treatment with 5-FU derivatives. The statement was developed as a consensus statement organized by the German Society for Hematology and Medical Oncology in cooperation with 13 medical associations from Austria, Germany, and Switzerland. Key Messages: (i) Patients should be tested for the 4 most common genetic DPYD variants before treatment with drugs containing FU. (ii) Testing forms the basis for a differentiated, risk-adapted algorithm with recommendations for treatment with FU-containing drugs. (iii) Testing may optionally be supplemented by therapeutic drug monitorin

    Molecular medicine and concepts of disease: the ethical value of a conceptual analysis of emerging biomedical technologies

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    Although it is now generally acknowledged that new biomedical technologies often produce new definitions and sometimes even new concepts of disease, this observation is rarely used in research that anticipates potential ethical issues in emerging technologies. This article argues that it is useful to start with an analysis of implied concepts of disease when anticipating ethical issues of biomedical technologies. It shows, moreover, that it is possible to do so at an early stage, i.e. when a technology is only just emerging. The specific case analysed here is that of ‘molecular medicine’. This group of emerging technologies combines a ‘cascade model’ of disease processes with a ‘personal pattern’ model of bodily functioning. Whereas the ethical implications of the first are partly familiar from earlier—albeit controversial—forms of preventive and predictive medicine, those of the second are quite novel and potentially far-reaching

    What is bad in cancer is good in the embryo: Importance of EMT in neural crest development

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