{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,7]],"date-time":"2026-02-07T18:10:47Z","timestamp":1770487847794,"version":"3.49.0"},"reference-count":48,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2020,10,7]],"date-time":"2020-10-07T00:00:00Z","timestamp":1602028800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["SFRH\/BD\/134107\/2017"],"award-info":[{"award-number":["SFRH\/BD\/134107\/2017"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["FRH\/BD\/138937\/2018"],"award-info":[{"award-number":["FRH\/BD\/138937\/2018"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["IF\/01704\/2014"],"award-info":[{"award-number":["IF\/01704\/2014"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["IF\/01704\/2014\/CP1229\/CT0001"],"award-info":[{"award-number":["IF\/01704\/2014\/CP1229\/CT0001"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000780","name":"European Commission","doi-asserted-by":"publisher","award":["FP7-HEALTH-2013-INNOVATION-1, GA n. 602640"],"award-info":[{"award-number":["FP7-HEALTH-2013-INNOVATION-1, GA n. 602640"]}],"id":[{"id":"10.13039\/501100000780","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Vaccines"],"abstract":"<jats:p>The use of non-standard culture conditions has proven efficient to increase cell performance and recombinant protein production in different cell hosts. However, the establishment of high-producing cell populations through adaptive laboratory evolution (ALE) has been poorly explored, in particular for insect cells. In this study, insect High Five cells were successfully adapted to grow at a neutral culture pH (7.0) through ALE for an improved production of influenza hemagglutinin (HA)-displaying virus-like particles (VLPs). A stepwise approach was used for the adaptation process, in which the culture pH gradually increased from standard 6.2 to 7.0 (\u0394Ph = 0.2\u20130.3), and cells were maintained at each pH value for 2\u20133 weeks until a constant growth rate and a cell viability over 95% were observed. These adapted cells enabled an increase in cell-specific HA productivity up to three-fold and volumetric HA titer of up to four-fold as compared to non-adapted cells. Of note, the adaptation process is the element driving increased specific HA productivity as a pH shift alone was inefficient at improving productivities. The production of HA-VLPs in adapted cells was successfully demonstrated at the bioreactor scale. The produced HA-VLPs show the typical size and morphology of influenza VLPs, thus confirming the null impact of the adaptation process and neutral culture pH on the quality of HA-VLPs produced. This work strengthens the potential of ALE as a bioprocess engineering strategy to improve the production of influenza HA-VLPs in insect High Five cells.<\/jats:p>","DOI":"10.3390\/vaccines8040589","type":"journal-article","created":{"date-parts":[[2020,10,7]],"date-time":"2020-10-07T09:12:58Z","timestamp":1602061978000},"page":"589","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":22,"title":["Improving Influenza HA-Vlps Production in Insect High Five Cells via Adaptive Laboratory Evolution"],"prefix":"10.3390","volume":"8","author":[{"given":"Ricardo","family":"Correia","sequence":"first","affiliation":[{"name":"IBET, Instituto de Biologia Experimental e Tecnol\u00f3gica, Apartado 12, 2780-901 Oeiras, Portugal"},{"name":"ITQB NOVA, Instituto de Tecnologia Qu\u00edmica e Biol\u00f3gica Ant\u00f3nio Xavier, Universidade Nova de Lisboa, Av. da Rep\u00fablica, 2780-157 Oeiras, Portugal"}]},{"given":"B\u00e1rbara","family":"Fernandes","sequence":"additional","affiliation":[{"name":"IBET, Instituto de Biologia Experimental e Tecnol\u00f3gica, Apartado 12, 2780-901 Oeiras, Portugal"},{"name":"ITQB NOVA, Instituto de Tecnologia Qu\u00edmica e Biol\u00f3gica Ant\u00f3nio Xavier, Universidade Nova de Lisboa, Av. da Rep\u00fablica, 2780-157 Oeiras, Portugal"}]},{"given":"Paula M.","family":"Alves","sequence":"additional","affiliation":[{"name":"IBET, Instituto de Biologia Experimental e Tecnol\u00f3gica, Apartado 12, 2780-901 Oeiras, Portugal"},{"name":"ITQB NOVA, Instituto de Tecnologia Qu\u00edmica e Biol\u00f3gica Ant\u00f3nio Xavier, Universidade Nova de Lisboa, Av. da Rep\u00fablica, 2780-157 Oeiras, Portugal"}]},{"given":"Manuel J.T.","family":"Carrondo","sequence":"additional","affiliation":[{"name":"IBET, Instituto de Biologia Experimental e Tecnol\u00f3gica, Apartado 12, 2780-901 Oeiras, Portugal"}]},{"given":"Ant\u00f3nio","family":"Rold\u00e3o","sequence":"additional","affiliation":[{"name":"IBET, Instituto de Biologia Experimental e Tecnol\u00f3gica, Apartado 12, 2780-901 Oeiras, Portugal"},{"name":"ITQB NOVA, Instituto de Tecnologia Qu\u00edmica e Biol\u00f3gica Ant\u00f3nio Xavier, Universidade Nova de Lisboa, Av. da Rep\u00fablica, 2780-157 Oeiras, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2020,10,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"407","DOI":"10.1146\/annurev.med.51.1.407","article-title":"Global Epidemiology of influenza: Past and present","volume":"51","author":"Cox","year":"2000","journal-title":"Annu. 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