"Application of CRISPR/Cas9 genome editing to improve recombinant protein production in CHO cells"

Lise Marie Grav*, Karen Julie la Cour Karottki, Jae Seong Lee, Helene Faustrup Kildegaard‡. Heterologous Protein Production in CHO Cells. Methods in Molecular Biology 1603: 101-118.

Genome editing has become an increasingly important aspect of Chinese Hamster Ovary (CHO ) cell line engineering for improving production of recombinant protein therapeutics. Currently, the focus is directed toward expanding the product diversity, controlling and improving product quality and yields..

"A consensus genome-scale reconstruction of Chinese hamster ovary cell metabolism"

Hooman Hefzi*, Kok Siong Ang*, Michael Hanscho*, Aarash Bordbar, David Ruckerbauer, Meiyappan Lakshmanan, Camila A Orellana, Deniz Baycin-Hizal, Yingxiang Huang, Daniel Ley, Veronica S Martinez, Sarantos Kyriakopoulos, Natalia E Jiménez, Daniel C Zielinsk. Cell systems 3(5): 434-443. e8.

Chinese hamster ovary (CHO) cells dominate biotherapeutic protein production and are widely used in mammalian cell line engineering research. To elucidate metabolic bottlenecks in protein production and to guide cell engineering and bioprocess optimization, we reconstructed the metabolic pathways in..

"Accelerated homology-directed targeted integration of transgenes in Chinese hamster ovary cells via CRISPR/Cas9 and fluorescent enrichment"

Jae Seong Lee*, Lise Marie Grav, Lasse Ebdrup Pedersen, Gyun Min Lee, Helene Faustrup Kildegaard‡. Biotechnology and Bioengineering 113(11): 2518-2523.

Targeted gene integration into site-specific loci can be achieved in Chinese hamster ovary (CHO) cells via CRISPR/Cas9 genome editing technology and the homology-directed repair (HDR) pathway. The low efficiency of HDR often requires antibiotic selection, which limits targeted integration of multipl..

"Chemical inhibition of autophagy: Examining its potential to increase the specific productivity of recombinant CHO cell lines"

Eric Baek*, Che Lin Kim, Mi Gyeom Kim, Jae Seong Lee, Gyun Min Lee‡. Biotechnology and Bioengineering 113(9): 1953-1961.

Chinese hamster ovary (CHO) cells activate and undergo apoptosis and autophagy for various environmental stresses. Unlike apoptosis, studies on increasing the production of therapeutic proteins in CHO cells by targeting the autophagy pathway are limited. In order to identify the effects of chemical ..

"One-step generation of triple knockout CHO cell lines using CRISPR/Cas9 and fluorescent enrichment"

Lise Marie Grav*, Jae Seong Lee*, Signe Gerling, Thomas Beuchert Kallehauge, Anders Holmgaard Hansen, Stefan Kol, Gyun Min Lee, Lasse Ebdrup Pedersen, Helene Faustrup Kildegaard‡. Biotechnology Journal 10(9): 1446-1456.

The CRISPR/Cas9 genome editing technology has previously been shown to be a highly efficient tool for generating gene disruptions in CHO cells. In this study we further demonstrate the applicability and efficiency of CRISPR/Cas9 genome editing by disrupting FUT8, BAK and BAX simultaneously in a mult..

"CRISPR/Cas9-mediated genome engineering of CHO cell factories: Application and perspectives"

Jae Seong Lee*, Lise Marie Grav, Nathan E Lewis, Helene Faustrup Kildegaard‡. Biotechnology Journal 10(7): 979-994.

Chinese hamster ovary (CHO) cells are the most widely used production host for therapeutic proteins. With the recent emergence of CHO genome sequences, CHO cell line engineering has taken on a new aspect through targeted genome editing. The bacterial clustered regularly interspaced short palindromic..

"Site-specific integration in CHO cells mediated by CRISPR/Cas9 and homology-directed DNA repair pathway"

Jae Seong Lee*, Thomas Beuchert Kallehauge, Lasse Ebdrup Pedersen, Helene Faustrup Kildegaard‡. Scientific Reports 5(1): 8572.

Chinese hamster ovary (CHO) cells are the most widely used mammalian hosts for production of therapeutic proteins. However, development of recombinant CHO cell lines has been hampered by unstable and variable transgene expression caused by random integration. Here we demonstrate efficient targeted g..

"Autophagy and its implication in Chinese hamster ovary cell culture"

Yeon Jung Kim*, Eric Baek, Jae Seong Lee, Gyun Min Lee‡. Biotechnology Letters 35(11): 1753-1763.

Chinese hamster ovary (CHO) cells, that are widely used for production of therapeutic proteins, are subjected to apoptosis and autophagy under the stresses induced by conditions such as nutrient deprivation, hyperosmolality and addition of sodium butyrate. To achieve a cost-effective level of produc..

"Anti-cell death engineering of CHO cells: co-overexpression of Bcl-2 for apoptosis inhibition, Beclin-1 for autophagy induction"

Jae Seong Lee*, Tae Kwang Ha, Jin Hyoung Park, Gyun Min Lee‡. Biotechnology and Bioengineering 110(8): 2195-2207.

Genetic engineering approaches to inhibit cell death in Chinese hamster ovary (CHO) cell cultures have been limited primarily to anti-apoptosis engineering. Recently, autophagy has received attention as a new anti-cell death engineering target in addition to apoptosis. In order to achieve a more eff..

"Overexpression of PACEsol improves BMP-7 processing in recombinant CHO cells"

Madhavi Sathyamurthy*, Jae Seong Lee, Jin Hyoung Park, Yeon Jung Kim, Ji Yeon Jeong, Ju Woong Jang, Gyun Min Lee‡. Journal of Biotechnology 164(2): 336-339.

Bone morphogenetic protein-7 (BMP-7) is a member of the TGF-β superfamily and plays a critical role in cartilage, bone, and kidney development. BMP-7 is synthesized as a large precursor and undergoes proteolytic cleavage by subtilisin-like proprotein convertase to secrete the functionally active mat..

"Rapamycin treatment inhibits CHO cell death in a serum‐free suspension culture by autophagy induction"

Jae Seong Lee*, Gyun Min Lee‡. Biotechnology and Bioengineering 109(12): 3093-3102.

Rapamycin, a specific mTOR inhibitor, has been used as a chemical activator in autophagy research both in vitro and in vivo. Recently, autophagy has received attention as an anti-cell death engineering target in addition to apoptosis in the Chinese hamster ovary (CHO) cell engineering field. Here, t..

"Estimation of autophagy pathway genes for autophagy induction: Overexpression of Atg9A does not induce autophagy in recombinant Chinese hamster ovary cells"

Jae Seong Lee*, Gyun Min Lee‡. Biochemical Engineering Journal 68: 221-226.

Autophagy, a self-eating process, has attracted attention as a new target for anti-cell death engineering of recombinant Chinese hamster ovary (rCHO) cells in order to improve culture performance. In an effort to obtain genetic targets for autophagy control, changes in the mRNA and protein expressio..

"Differential induction of autophagy in caspase-3/7 down-regulating and Bcl-2 overexpressing recombinant CHO cells subjected to sodium butyrate treatment"

Jae Seong Lee*, Yeon Jung Kim, Che Lin Kim, Gyun Min Lee‡. Journal of Biotechnology 161(1): 34-41.

Previous research showed that co-down-regulation of caspase-3/7 in rCHO cells, unlike Bcl-2 overexpression, did not effectively block apoptotic cell death induced by 3mM sodium butyrate (NaBu). Here, it is found that the control of autophagy is also related to this different response to NaBu treatme..

"Current state and perspectives on erythropoietin production"

Jae Seong Lee*, Tae Kwang Ha, Seung Joo Lee, Gyun Min Lee‡. Applied Microbiology and Biotechnology 95(6): 1405-1416.

Erythropoietin is a major regulator of erythropoiesis which maintains the body's red blood cell mass and tissue oxygenation at an optimum level. Recombinant human erythropoietin (rhEPO), which is a widely used therapeutic agent for the treatment of anemia and which represents one of the largest biop..

"Monitoring of autophagy in Chinese hamster ovary cells using flow cytometry"

Jae Seong Lee*, Gyun Min Lee‡. Methods 56(3): 375-382.

Recently, autophagy, which is a degradative process, has drawn attention as an anti-cell death engineering target in addition to apoptosis in recombinant Chinese hamster ovary (rCHO) cell cultures for enhanced production of therapeutic proteins. Appropriate autophagy monitoring methods, that are sui..