{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,16]],"date-time":"2026-07-16T23:09:24Z","timestamp":1784243364201,"version":"3.55.0"},"reference-count":109,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2023,9,27]],"date-time":"2023-09-27T00:00:00Z","timestamp":1695772800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Hessen State Ministry of Higher Education, Research and the Arts"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Yellow Fever (YF) is a severe disease that, while preventable through vaccination, lacks rapid intervention options for those already infected. There is an urgent need for passive immunization techniques using YF-virus-like particles (YF-VLPs). To address this, we successfully established a bioreactor-based production process for YF-VLPs, leveraging transient transfection and integrating Process Analytical Technology. A cornerstone of this approach was the optimization of plasmid DNA (pDNA) production to a yield of 11 mg\/L using design of experiments. Glucose, NaCl, yeast extract, and a phosphate buffer showed significant influence on specific pDNA yield. The preliminary work for VLP-production in bioreactor showed adjustments to the HEK cell density, the polyplex formation duration, and medium exchanges effectively elevated transfection efficiencies. The additive Pluronic F-68 was neutral in its effects, and anti-clumping agents (ACA) adversely affected the transfection process. Finally, we established the stirred-tank bioreactor process with integrated dielectric spectroscopy, which gave real-time insight in relevant process steps, e.g., cell growth, polyplex uptake, and harvest time. We confirmed the presence and integrity of YF-VLP via Western blot, imaging flow cytometry measurement, and transmission electron microscopy. The YF-VLP production process can serve as a platform to produce VLPs as passive immunizing agents against other neglected tropical diseases.<\/jats:p>","DOI":"10.3390\/v15102013","type":"journal-article","created":{"date-parts":[[2023,9,28]],"date-time":"2023-09-28T01:42:12Z","timestamp":1695865332000},"page":"2013","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["A Bioreactor-Based Yellow Fever Virus-like Particle Production Process with Integrated Process Analytical Technology Based on Transient Transfection"],"prefix":"10.3390","volume":"15","author":[{"given":"Gregor","family":"Dekevic","sequence":"first","affiliation":[{"name":"Institute of Bioprocess Engineering and Pharmaceutical Technology, University of Applied Sciences Mittelhessen, Wiesenstrasse 14, 35390 Giessen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tobias","family":"Tertel","sequence":"additional","affiliation":[{"name":"Institute for Transfusion Medicine, University Hospital Essen, University of Duisburg-Essen, Virchowstrasse 179, 45147 Essen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lars","family":"Tasto","sequence":"additional","affiliation":[{"name":"Institute of Bioprocess Engineering and Pharmaceutical Technology, University of Applied Sciences Mittelhessen, Wiesenstrasse 14, 35390 Giessen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Deborah","family":"Schmidt","sequence":"additional","affiliation":[{"name":"Institute of Bioprocess Engineering and Pharmaceutical Technology, University of Applied Sciences Mittelhessen, Wiesenstrasse 14, 35390 Giessen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2446-948X","authenticated-orcid":false,"given":"Bernd","family":"Giebel","sequence":"additional","affiliation":[{"name":"Institute for Transfusion Medicine, University Hospital Essen, University of Duisburg-Essen, Virchowstrasse 179, 45147 Essen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7485-500X","authenticated-orcid":false,"given":"Peter","family":"Czermak","sequence":"additional","affiliation":[{"name":"Institute of Bioprocess Engineering and Pharmaceutical Technology, University of Applied Sciences Mittelhessen, Wiesenstrasse 14, 35390 Giessen, Germany"},{"name":"Faculty of Biology and Chemistry, University of Giessen, Heinrich-Buff-Ring 17, 35392 Giessen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9266-1356","authenticated-orcid":false,"given":"Denise","family":"Salzig","sequence":"additional","affiliation":[{"name":"Institute of Bioprocess Engineering and Pharmaceutical Technology, University of Applied Sciences Mittelhessen, Wiesenstrasse 14, 35390 Giessen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,9,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Garske, T., Van Kerkhove, M.D., Yactayo, S., Ronveaux, O., Lewis, R.F., Staples, J.E., Perea, W., Ferguson, N.M., and Yellow Fever Expert Committee (2014). 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