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Woo HJ, Kim J, Kim SM, Kim D, Moon JY, Park D, Lee JS. Context-dependent genomic locus effects on antibody production in recombinant Chinese hamster ovary cells generated through random integration. Comput Struct Biotechnol J 2024; 23:1654-1665. [PMID: 38680870 PMCID: PMC11046053 DOI: 10.1016/j.csbj.2024.04.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 03/30/2024] [Accepted: 04/07/2024] [Indexed: 05/01/2024] Open
Abstract
High-yield production of therapeutic protein using Chinese hamster ovary (CHO) cells requires stable cell line development (CLD). CLD typically uses random integration of transgenes; however, this results in clonal variation and subsequent laborious clone screening. Therefore, site-specific integration of a protein expression cassette into a desired chromosomal locus showing high transcriptional activity and stability, referred to as a hot spot, is emerging. Although positional effects are important for therapeutic protein expression, the sequence-specific mechanisms by which hotspots work are not well understood. In this study, we performed whole-genome sequencing (WGS) to locate randomly inserted vectors in the genome of recombinant CHO cells expressing high levels of monoclonal antibodies (mAbs) and experimentally validated these locations and vector compositions. The integration site was characterized by active histone marks and potential enhancer activities, and clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) mediated indel mutations in the region upstream of the integration site led to a significant reduction in specific antibody productivity by up to 30%. Notably, the integration site and its core region did not function equivalently outside the native genomic context, showing a minimal effect on the increase in exogenous protein expression in the host cell line. We also observed a superior production capacity of the mAb expressing cell line compared to that of the host cell line. Collectively, this study demonstrates that developing recombinant CHO cell lines to produce therapeutic proteins at high levels requires a balance of factors including transgene configuration, genomic locus landscape, and host cell properties.
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Affiliation(s)
- Hyun Jee Woo
- Department of Molecular Science and Technology, Ajou University, Suwon 16499, Republic of Korea
| | - Jaehoon Kim
- Department of Molecular Science and Technology, Ajou University, Suwon 16499, Republic of Korea
- Molecular Science and Technology Research Center, Ajou University, Suwon 16499, Republic of Korea
| | - Seul Mi Kim
- Department of Molecular Science and Technology, Ajou University, Suwon 16499, Republic of Korea
| | - Dongwoo Kim
- Department of Molecular Science and Technology, Ajou University, Suwon 16499, Republic of Korea
| | - Jae Yun Moon
- Department of Molecular Science and Technology, Ajou University, Suwon 16499, Republic of Korea
| | - Daechan Park
- Department of Molecular Science and Technology, Ajou University, Suwon 16499, Republic of Korea
- Department of Biological Sciences, Ajou University, Suwon 16499, Republic of Korea
| | - Jae Seong Lee
- Department of Molecular Science and Technology, Ajou University, Suwon 16499, Republic of Korea
- Department of Applied Chemistry and Biological Engineering, Ajou University, Suwon 16499, Republic of Korea
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Schloßhauer JL, Tholen L, Körner A, Kubick S, Chatzopoulou S, Hönow A, Zemella A. Promoting the production of challenging proteins via induced expression in CHO cells and modified cell-free lysates harboring T7 RNA polymerase and mutant eIF2α. Synth Syst Biotechnol 2024; 9:416-424. [PMID: 38601208 PMCID: PMC11004649 DOI: 10.1016/j.synbio.2024.03.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Revised: 02/12/2024] [Accepted: 03/16/2024] [Indexed: 04/12/2024] Open
Abstract
Chinese hamster ovary (CHO) cells are crucial in biopharmaceutical production due to their scalability and capacity for human-like post-translational modifications. However, toxic proteins and membrane proteins are often difficult-to-express in living cells. Alternatively, cell-free protein synthesis can be employed. This study explores innovative strategies for enhancing the production of challenging proteins through the modification of CHO cells by investigating both, cell-based and cell-free approaches. A major result in our study involves the integration of a mutant eIF2 translation initiation factor and T7 RNA polymerase into CHO cell lysates for cell-free protein synthesis. This resulted in elevated yields, while eliminating the necessity for exogenous additions during cell-free production, thereby substantially enhancing efficiency. Additionally, we explore the potential of the Rosa26 genomic site for the integration of T7 RNA polymerase and cell-based tetracycline-controlled protein expression. These findings provide promising advancements in bioproduction technologies, offering flexibility to switch between cell-free and cell-based protein production as needed.
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Affiliation(s)
- Jeffrey L. Schloßhauer
- Fraunhofer Project Group PZ-Syn of the Fraunhofer Institute for Cell Therapy and Immunology-IZI, Branch Bioanalytics and Bioprocesses-IZI-BB, Am Mühlenberg, Potsdam, Germany
- Fraunhofer Institute for Cell Therapy and Immunology-IZI, Branch Bioanalytics and Bioprocesses-IZI-BB, Am Mühlenberg, Potsdam, Germany
- Institute for Chemistry and Biochemistry, Laboratory of Protein Biochemistry, Freie Universität Berlin, Thielallee 63, 14195, Berlin, Germany
| | - Lena Tholen
- Fraunhofer Institute for Cell Therapy and Immunology-IZI, Branch Bioanalytics and Bioprocesses-IZI-BB, Am Mühlenberg, Potsdam, Germany
| | - Alexander Körner
- Fraunhofer Institute for Cell Therapy and Immunology-IZI, Branch Bioanalytics and Bioprocesses-IZI-BB, Am Mühlenberg, Potsdam, Germany
- Institute of Biotechnology, Technische Universität Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany
| | - Stefan Kubick
- Fraunhofer Institute for Cell Therapy and Immunology-IZI, Branch Bioanalytics and Bioprocesses-IZI-BB, Am Mühlenberg, Potsdam, Germany
- Faculty of Health Sciences, Joint Faculty of the Brandenburg University of Technology Cottbus –Senftenberg, The Brandenburg Medical School Theodor Fontane, University of Potsdam, Potsdam, Germany
- Institute for Chemistry and Biochemistry, Laboratory of Protein Biochemistry, Freie Universität Berlin, Thielallee 63, 14195, Berlin, Germany
| | - Sofia Chatzopoulou
- Fraunhofer Institute for Cell Therapy and Immunology-IZI, Branch Bioanalytics and Bioprocesses-IZI-BB, Am Mühlenberg, Potsdam, Germany
| | - Anja Hönow
- New/era/mabs GmbH, August-Bebel-Str. 89, 14482, Potsdam, Germany
| | - Anne Zemella
- Fraunhofer Institute for Cell Therapy and Immunology-IZI, Branch Bioanalytics and Bioprocesses-IZI-BB, Am Mühlenberg, Potsdam, Germany
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Adibzadeh S, Amiri S, Barkhordari F, Mowla SJ, Bayat H, Ghanbari S, Faghihi F, Davami F. CHO cell engineering via targeted integration of circular miR-21 decoy using CRISPR/RMCE hybrid system. Appl Microbiol Biotechnol 2024; 108:434. [PMID: 39120640 PMCID: PMC11315787 DOI: 10.1007/s00253-024-13266-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2024] [Revised: 07/21/2024] [Accepted: 07/24/2024] [Indexed: 08/10/2024]
Abstract
Chinese hamster ovary (CHO) cells, widely acknowledged as the preferred host system for industrial recombinant protein manufacturing, play a crucial role in developing pharmaceuticals, including anticancer therapeutics. Nevertheless, mammalian cell-based biopharmaceutical production methods are still beset by cellular constraints such as limited growth and poor productivity. MicroRNA-21 (miR-21) has a major impact on a variety of malignancies, including glioblastoma multiforme (GBM). However, reduced productivity and growth rate have been linked to miR-21 overexpression in CHO cells. The current study aimed to engineer a recombinant CHO (rCHO) cell using the CRISPR-mediated precise integration into target chromosome (CRIS-PITCh) system coupled with the Bxb1 recombinase-mediated cassette exchange (RMCE) to express a circular miR-21 decoy (CM21D) with five bulged binding sites for miR-21 sponging. Implementing the ribonucleoprotein (RNP) delivery method, a landing pad was inserted into the genome utilizing the CRIS-PITCh technique. Subsequently, the CM21D cassette flanked by Bxb1 attB was then retargeted into the integrated landing pad using the RMCE/Bxb1 system. This strategy raised the targeting efficiency by 1.7-fold, and off-target effects were decreased. The miR-21 target genes (Pdcd4 and Atp11b) noticed a significant increase in expression upon the miR-21 sponging through CM21D. Following the expression of CM21D, rCHO cells showed a substantial decrease in doubling time and a 1.3-fold increase in growth rate. Further analysis showed an increased yield of hrsACE2, a secretory recombinant protein, by 2.06-fold. Hence, we can conclude that sponging-induced inhibition of miR-21 may lead to a growth rate increase that could be linked to increased CHO cell productivity. For industrial cell lines, including CHO cells, an increase in productivity is crucial. The results of our research indicate that CM21D is an auspicious CHO engineering approach. KEY POINTS: • CHO is an ideal host cell line for producing industrial therapeutics manufacturing, and miR-21 is downregulated in CHO cells, which produce recombinant proteins. • The miR-21 target genes noticed a significant increase in expression upon the miR-21 sponging through CM21D. Additionally, sponging of miR-21 by CM21D enhanced the growth rate of CHO cells. • Productivity and growth rate were increased in CHO cells expressing recombinant hrs-ACE2 protein after CM21D knocking in.
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Affiliation(s)
- Setare Adibzadeh
- Department of Medical Biotechnology, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran
- Student Research Committee, Pasteur Institute of Iran, Tehran, Iran
| | - Shahin Amiri
- Department of Medical Biotechnology, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran
- Student Research Committee, Pasteur Institute of Iran, Tehran, Iran
| | - Farzaneh Barkhordari
- Department of Medical Biotechnology, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran
| | - Seyed Javad Mowla
- Department of Molecular Genetics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran
| | - Hadi Bayat
- Biochemical Neuroendocrinology, Institut de Recherches Cliniques de Montréal (IRCM), affiliated to the Division of Experimental Medicine, Faculty of Medicine and Health Sciences, McGill University, Montréal, H2W 1R7, Canada
| | - Samaneh Ghanbari
- Department of Medical Biotechnology, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran
| | - Faezeh Faghihi
- Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, Iran.
| | - Fatemeh Davami
- Department of Medical Biotechnology, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran.
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Bai S, Luo H, Tong H, Wu Y, Yuan Y. Advances on transfer and maintenance of large DNA in bacteria, fungi, and mammalian cells. Biotechnol Adv 2024; 76:108421. [PMID: 39127411 DOI: 10.1016/j.biotechadv.2024.108421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Revised: 05/07/2024] [Accepted: 08/04/2024] [Indexed: 08/12/2024]
Abstract
Advances in synthetic biology allow the design and manipulation of DNA from the scale of genes to genomes, enabling the engineering of complex genetic information for application in biomanufacturing, biomedicine and other areas. The transfer and subsequent maintenance of large DNA are two core steps in large scale genome rewriting. Compared to small DNA, the high molecular weight and fragility of large DNA make its transfer and maintenance a challenging process. This review outlines the methods currently available for transferring and maintaining large DNA in bacteria, fungi, and mammalian cells. It highlights their mechanisms, capabilities and applications. The transfer methods are categorized into general methods (e.g., electroporation, conjugative transfer, induced cell fusion-mediated transfer, and chemical transformation) and specialized methods (e.g., natural transformation, mating-based transfer, virus-mediated transfection) based on their applicability to recipient cells. The maintenance methods are classified into genomic integration (e.g., CRISPR/Cas-assisted insertion) and episomal maintenance (e.g., artificial chromosomes). Additionally, this review identifies the major technological advantages and disadvantages of each method and discusses the development for large DNA transfer and maintenance technologies.
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Affiliation(s)
- Song Bai
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, 300072 Tianjin, China; Frontiers Research Institute for Synthetic Biology, Tianjin University, Tianjin 300072, China
| | - Han Luo
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, 300072 Tianjin, China; Frontiers Research Institute for Synthetic Biology, Tianjin University, Tianjin 300072, China
| | - Hanze Tong
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, 300072 Tianjin, China; Frontiers Research Institute for Synthetic Biology, Tianjin University, Tianjin 300072, China
| | - Yi Wu
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, 300072 Tianjin, China; Frontiers Research Institute for Synthetic Biology, Tianjin University, Tianjin 300072, China. @tju.edu.cn
| | - Yingjin Yuan
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, 300072 Tianjin, China; Frontiers Research Institute for Synthetic Biology, Tianjin University, Tianjin 300072, China
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Yoon C, Lee EJ, Kim D, Joung S, Kim Y, Jung H, Kim YG, Lee GM. SiMPl-GS: Advancing Cell Line Development via Synthetic Selection Marker for Next-Generation Biopharmaceutical Production. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024:e2405593. [PMID: 39105414 DOI: 10.1002/advs.202405593] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2024] [Revised: 07/24/2024] [Indexed: 08/07/2024]
Abstract
Rapid and efficient cell line development (CLD) process is essential to expedite therapeutic protein development. However, the performance of widely used glutamine-based selection systems is limited by low selection efficiency, stringency, and the inability to select multiple genes. Therefore, an AND-gate synthetic selection system is rationally designed using split intein-mediated protein ligation of glutamine synthetase (GS) (SiMPl-GS). Split sites of the GS are selected using a computational approach and validated with GS-knockout Chinese hamster ovary cells for their potential to enable cell survival in a glutamine-free medium. In CLD, SiMPl-GS outperforms the wild-type GS by selectively enriching high producers. Unlike wild-type GS, SiMPl-GS results in cell pools in which most cells produce high levels of therapeutic proteins. Harnessing orthogonal split intein pairs further enables the selection of four plasmids with a single selection, streamlining multispecific antibody-producing CLD. Taken together, SiMPl-GS is a simple yet effective means to expedite CLD for therapeutic protein production.
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Affiliation(s)
- Chansik Yoon
- Department of Biological Sciences, KAIST, Daejeon, 34141, Republic of Korea
| | - Eun-Ji Lee
- Biotherapeutics Translational Research Center, KRIBB, Daejeon, 34113, Republic of Korea
- Department of Bioprocess Engineering, KRIBB School of Biotechnology, UST, Daejeon, 34141, Republic of Korea
| | - Dongil Kim
- Department of Biological Sciences, KAIST, Daejeon, 34141, Republic of Korea
| | - Siyun Joung
- Department of Biological Sciences, KAIST, Daejeon, 34141, Republic of Korea
| | - Yujin Kim
- Department of Biological Sciences, KAIST, Daejeon, 34141, Republic of Korea
| | - Heungchae Jung
- Department of Bioprocess Engineering, KRIBB School of Biotechnology, UST, Daejeon, 34141, Republic of Korea
- BIO Center, Daejeon Technopark, Daejeon, 34054, Republic of Korea
| | - Yeon-Gu Kim
- Biotherapeutics Translational Research Center, KRIBB, Daejeon, 34113, Republic of Korea
- Department of Bioprocess Engineering, KRIBB School of Biotechnology, UST, Daejeon, 34141, Republic of Korea
| | - Gyun Min Lee
- Department of Biological Sciences, KAIST, Daejeon, 34141, Republic of Korea
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Tung J, Huang L, George G, Harding HP, Ron D, Ordonez A. A genome-wide CRISPR/Cas9 screen identifies calreticulin as a selective repressor of ATF6α. eLife 2024; 13:RP96979. [PMID: 39073063 PMCID: PMC11286266 DOI: 10.7554/elife.96979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/30/2024] Open
Abstract
Activating transcription factor 6 (ATF6) is one of three endoplasmic reticulum (ER) transmembrane stress sensors that mediate the unfolded protein response (UPR). Despite its crucial role in long-term ER stress adaptation, regulation of ATF6 alpha (α) signalling remains poorly understood, possibly because its activation involves ER-to-Golgi and nuclear trafficking. Here, we generated an ATF6α/Inositol-requiring kinase 1 (IRE1) dual UPR reporter CHO-K1 cell line and performed an unbiased genome-wide CRISPR/Cas9 mutagenesis screen to systematically profile genetic factors that specifically contribute to ATF6α signalling in the presence and absence of ER stress. The screen identified both anticipated and new candidate genes that regulate ATF6α activation. Among these, calreticulin (CRT), a key ER luminal chaperone, selectively repressed ATF6α signalling: Cells lacking CRT constitutively activated a BiP::sfGFP ATF6α-dependent reporter, had higher BiP levels and an increased rate of trafficking and processing of ATF6α. Purified CRT interacted with the luminal domain of ATF6α in vitro and the two proteins co-immunoprecipitated from cell lysates. CRT depletion exposed a negative feedback loop implicating ATF6α in repressing IRE1 activity basally and overexpression of CRT reversed this repression. Our findings indicate that CRT, beyond its known role as a chaperone, also serves as an ER repressor of ATF6α to selectively regulate one arm of the UPR.
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Affiliation(s)
- Joanne Tung
- Cambridge Institute for Medical Research (CIMR), University of Cambridge, Cambridge Biomedical CampusCambridgeUnited Kingdom
| | - Lei Huang
- Cambridge Institute for Medical Research (CIMR), University of Cambridge, Cambridge Biomedical CampusCambridgeUnited Kingdom
| | - Ginto George
- Cambridge Institute for Medical Research (CIMR), University of Cambridge, Cambridge Biomedical CampusCambridgeUnited Kingdom
| | - Heather P Harding
- Cambridge Institute for Medical Research (CIMR), University of Cambridge, Cambridge Biomedical CampusCambridgeUnited Kingdom
| | - David Ron
- Cambridge Institute for Medical Research (CIMR), University of Cambridge, Cambridge Biomedical CampusCambridgeUnited Kingdom
| | - Adriana Ordonez
- Cambridge Institute for Medical Research (CIMR), University of Cambridge, Cambridge Biomedical CampusCambridgeUnited Kingdom
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Cho K, Lee JS. Revisiting the impact of genomic hot spots: C12orf35 locus as a hot spot and engineering target. Biotechnol Bioeng 2024. [PMID: 38978356 DOI: 10.1002/bit.28801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2024] [Revised: 06/18/2024] [Accepted: 06/30/2024] [Indexed: 07/10/2024]
Abstract
Traditional Chinese hamster ovary (CHO) cell line development is based on random integration (RI) of transgene that causes clonal variation and subsequent large-scale clone screening. Therefore, site-specific integration (SSI) of transgenes into genomic hot spots has recently emerged as an alternative method for cell line development. However, the specific mechanisms underlying hot spot site formation remain unclear. In this study, we aimed to generate landing pad (LP) cell lines via the RI of transgenes encoding fluorescent reporter proteins flanked by recombination sites to facilitate recombinase-mediated cassette exchange. The RI-based LP cell line expressing high reporter levels with spontaneous C12orf35 locus deletion exhibited similar reporter fluorescent protein levels compared to targeted integrants with an identical reporter LP construct at the CHO genome hot spot, the C12orf35 locus. Additionally, Resf1, a C12orf35 locus gene, knockout (KO) in the RI-based LP cell line with conserved C12orf35 increased reporter expression levels, comparable to those in cell lines with C12orf35 locus disruption. These results indicate that the effect of SSI into the C12orf35 locus, a genomic hot spot, on high-level transgene expression was caused by C12orf35 disruption. In contrast to C12orf35 KO, KO at other well-known hot spot sites at specific loci of genes, including Fer1L4, Hprt1, Adgrl4, Clcc1, Dop1b, and Ddc, did not increase transgene expression. Overall, our findings suggest that C12orf35 is a promising engineering target and a hot spot for SSI-based cell line development.
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Affiliation(s)
- Kyuhee Cho
- Department of Molecular Science and Technology, Ajou University, Suwon, Republic of Korea
| | - Jae Seong Lee
- Department of Molecular Science and Technology, Ajou University, Suwon, Republic of Korea
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Peterman EL, Ploessl DS, Galloway KE. Accelerating Diverse Cell-Based Therapies Through Scalable Design. Annu Rev Chem Biomol Eng 2024; 15:267-292. [PMID: 38594944 DOI: 10.1146/annurev-chembioeng-100722-121610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/11/2024]
Abstract
Augmenting cells with novel, genetically encoded functions will support therapies that expand beyond natural capacity for immune surveillance and tissue regeneration. However, engineering cells at scale with transgenic cargoes remains a challenge in realizing the potential of cell-based therapies. In this review, we introduce a range of applications for engineering primary cells and stem cells for cell-based therapies. We highlight tools and advances that have launched mammalian cell engineering from bioproduction to precision editing of therapeutically relevant cells. Additionally, we examine how transgenesis methods and genetic cargo designs can be tailored for performance. Altogether, we offer a vision for accelerating the translation of innovative cell-based therapies by harnessing diverse cell types, integrating the expanding array of synthetic biology tools, and building cellular tools through advanced genome writing techniques.
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Affiliation(s)
- Emma L Peterman
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA;
| | - Deon S Ploessl
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA;
| | - Kate E Galloway
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA;
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Huhtinen O, Prince S, Lamminmäki U, Salbo R, Kulmala A. Increased stable integration efficiency in CHO cells through enhanced nuclear localization of Bxb1 serine integrase. BMC Biotechnol 2024; 24:44. [PMID: 38926833 PMCID: PMC11210126 DOI: 10.1186/s12896-024-00871-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Accepted: 06/20/2024] [Indexed: 06/28/2024] Open
Abstract
BACKGROUND Mammalian display is an appealing technology for therapeutic antibody development. Despite the advantages of mammalian display, such as full-length IgG display with mammalian glycosylation and its inherent ability to select antibodies with good biophysical properties, the restricted library size and large culture volumes remain challenges. Bxb1 serine integrase is commonly used for the stable genomic integration of antibody genes into mammalian cells, but presently lacks the efficiency required for the display of large mammalian display libraries. To increase the Bxb1 integrase-mediated stable integration efficiency, our study investigates factors that potentially affect the nuclear localization of Bxb1 integrase. METHODS In an attempt to enhance Bxb1 serine integrase-mediated integration efficiency, we fused various nuclear localization signals (NLS) to the N- and C-termini of the integrase. Concurrently, we co-expressed multiple proteins associated with nuclear transport to assess their impact on the stable integration efficiency of green fluorescent protein (GFP)-encoding DNA and an antibody display cassette into the genome of Chinese hamster ovary (CHO) cells containing a landing pad for Bxb1 integrase-mediated integration. RESULTS The nucleoplasmin NLS from Xenopus laevis, when fused to the C-terminus of Bxb1 integrase, demonstrated the highest enhancement in stable integration efficiency among the tested NLS fusions, exhibiting over a 6-fold improvement compared to Bxb1 integrase lacking an NLS fusion. Subsequent additions of extra NLS fusions to the Bxb1 integrase revealed an additional 131% enhancement in stable integration efficiency with the inclusion of two copies of C-terminal nucleoplasmin NLS fusions. Further improvement was achieved by co-expressing the Ran GTPase-activating protein (RanGAP). Finally, to validate the applicability of these findings to more complex proteins, the DNA encoding the membrane-bound clinical antibody abrilumab was stably integrated into the genome of CHO cells using Bxb1 integrase with two copies of C-terminal nucleoplasmin NLS fusions and co-expression of RanGAP. This approach demonstrated over 14-fold increase in integration efficiency compared to Bxb1 integrase lacking an NLS fusion. CONCLUSIONS This study demonstrates that optimizing the NLS sequence fusion for Bxb1 integrase significantly enhances the stable genomic integration efficiency. These findings provide a practical approach for constructing larger libraries in mammalian cells through the stable integration of genes into a genomic landing pad.
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Affiliation(s)
- Olli Huhtinen
- Protein & Antibody Engineering, Orion Corporation, Turku, Finland.
- Department of Life Technologies, University of Turku, Turku, Finland.
| | - Stuart Prince
- MediCity Research Laboratory, University of Turku, Turku, Finland
- Institute of Biomedicine, University of Turku, Turku, Finland
| | - Urpo Lamminmäki
- Department of Life Technologies, University of Turku, Turku, Finland
| | - Rune Salbo
- Protein & Antibody Engineering, Orion Corporation, Turku, Finland
| | - Antti Kulmala
- Protein & Antibody Engineering, Orion Corporation, Turku, Finland.
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Rossi M, Breman E. Engineering strategies to safely drive CAR T-cells into the future. Front Immunol 2024; 15:1411393. [PMID: 38962002 PMCID: PMC11219585 DOI: 10.3389/fimmu.2024.1411393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2024] [Accepted: 05/27/2024] [Indexed: 07/05/2024] Open
Abstract
Chimeric antigen receptor (CAR) T-cell therapy has proven a breakthrough in cancer treatment in the last decade, giving unprecedented results against hematological malignancies. All approved CAR T-cell products, as well as many being assessed in clinical trials, are generated using viral vectors to deploy the exogenous genetic material into T-cells. Viral vectors have a long-standing clinical history in gene delivery, and thus underwent iterations of optimization to improve their efficiency and safety. Nonetheless, their capacity to integrate semi-randomly into the host genome makes them potentially oncogenic via insertional mutagenesis and dysregulation of key cellular genes. Secondary cancers following CAR T-cell administration appear to be a rare adverse event. However several cases documented in the last few years put the spotlight on this issue, which might have been underestimated so far, given the relatively recent deployment of CAR T-cell therapies. Furthermore, the initial successes obtained in hematological malignancies have not yet been replicated in solid tumors. It is now clear that further enhancements are needed to allow CAR T-cells to increase long-term persistence, overcome exhaustion and cope with the immunosuppressive tumor microenvironment. To this aim, a variety of genomic engineering strategies are under evaluation, most relying on CRISPR/Cas9 or other gene editing technologies. These approaches are liable to introduce unintended, irreversible genomic alterations in the product cells. In the first part of this review, we will discuss the viral and non-viral approaches used for the generation of CAR T-cells, whereas in the second part we will focus on gene editing and non-gene editing T-cell engineering, with particular regard to advantages, limitations, and safety. Finally, we will critically analyze the different gene deployment and genomic engineering combinations, delineating strategies with a superior safety profile for the production of next-generation CAR T-cell.
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11
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Wang Z, Chen C, Ge X. Large T antigen mediated target gene replication improves site-specific recombination efficiency. Front Bioeng Biotechnol 2024; 12:1377167. [PMID: 38737535 PMCID: PMC11082406 DOI: 10.3389/fbioe.2024.1377167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Accepted: 04/11/2024] [Indexed: 05/14/2024] Open
Abstract
With advantages of high-fidelity, monoclonality and large cargo capacity, site-specific recombination (SSR) holds great promises for precise genomic modifications. However, broad applications of SSR have been hurdled by low integration efficiency, and the amount of donor DNA available in nucleus for SSR presents as a limiting factor. Inspired by the DNA replication mechanisms observed in double-stranded DNA virus SV40, we hypothesized that expression of SV40 large T antigen (TAg) can increase the copy number of the donor plasmid bearing an SV40 origin, and in consequence promote recombination events. This hypothesis was tested with dual recombinase-mediated cassette exchange (RMCE) in suspension 293F cells. Results showed that TAg co-transfection significantly enhanced SSR in polyclonal cells. In the monoclonal cell line carrying a single landing pad at an identified genomic locus, 12% RMCE efficiency was achieved, and such improvement was indeed correlated with donor plasmid amplification. The developed TAg facilitated RMCE (T-RMCE) was exploited for the construction of large libraries of >107 diversity, from which GFP variants with enhanced fluorescence were isolated. We expect the underlying principle of target gene amplification can be applicable to other SSR processes and gene editing approaches in general for directed evolution and large-scale genomic screening in mammalian cells.
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Affiliation(s)
- Zening Wang
- Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, TX, United States
- Department of Chemical and Environmental Engineering, University of California Riverside, Riverside, CA, United States
| | - Chuan Chen
- Department of Chemical and Environmental Engineering, University of California Riverside, Riverside, CA, United States
| | - Xin Ge
- Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, TX, United States
- Department of Chemical and Environmental Engineering, University of California Riverside, Riverside, CA, United States
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12
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Boob AG, Zhu Z, Intasian P, Jain M, Petrov V, Lane ST, Tan SI, Xun G, Zhao H. CRISPR-COPIES: an in silico platform for discovery of neutral integration sites for CRISPR/Cas-facilitated gene integration. Nucleic Acids Res 2024; 52:e30. [PMID: 38346683 PMCID: PMC11014336 DOI: 10.1093/nar/gkae062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2023] [Revised: 01/09/2024] [Accepted: 01/19/2024] [Indexed: 04/14/2024] Open
Abstract
The CRISPR/Cas system has emerged as a powerful tool for genome editing in metabolic engineering and human gene therapy. However, locating the optimal site on the chromosome to integrate heterologous genes using the CRISPR/Cas system remains an open question. Selecting a suitable site for gene integration involves considering multiple complex criteria, including factors related to CRISPR/Cas-mediated integration, genetic stability, and gene expression. Consequently, identifying such sites on specific or different chromosomal locations typically requires extensive characterization efforts. To address these challenges, we have developed CRISPR-COPIES, a COmputational Pipeline for the Identification of CRISPR/Cas-facilitated intEgration Sites. This tool leverages ScaNN, a state-of-the-art model on the embedding-based nearest neighbor search for fast and accurate off-target search, and can identify genome-wide intergenic sites for most bacterial and fungal genomes within minutes. As a proof of concept, we utilized CRISPR-COPIES to characterize neutral integration sites in three diverse species: Saccharomyces cerevisiae, Cupriavidus necator, and HEK293T cells. In addition, we developed a user-friendly web interface for CRISPR-COPIES (https://biofoundry.web.illinois.edu/copies/). We anticipate that CRISPR-COPIES will serve as a valuable tool for targeted DNA integration and aid in the characterization of synthetic biology toolkits, enable rapid strain construction to produce valuable biochemicals, and support human gene and cell therapy applications.
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Affiliation(s)
- Aashutosh Girish Boob
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- DOE Center for Advanced Bioenergy and Bioproducts Innovation, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Zhixin Zhu
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Pattarawan Intasian
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- School of Biomolecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology, Wangchan Valley, Rayong 21210, Thailand
| | - Manan Jain
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- DOE Center for Advanced Bioenergy and Bioproducts Innovation, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Vassily Andrew Petrov
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- DOE Center for Advanced Bioenergy and Bioproducts Innovation, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Stephan Thomas Lane
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- DOE Center for Advanced Bioenergy and Bioproducts Innovation, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Shih-I Tan
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- DOE Center for Advanced Bioenergy and Bioproducts Innovation, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Guanhua Xun
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Huimin Zhao
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- DOE Center for Advanced Bioenergy and Bioproducts Innovation, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
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13
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Kumar V, Barwal A, Sharma N, Mir DS, Kumar P, Kumar V. Therapeutic proteins: developments, progress, challenges, and future perspectives. 3 Biotech 2024; 14:112. [PMID: 38510462 PMCID: PMC10948735 DOI: 10.1007/s13205-024-03958-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2023] [Accepted: 02/13/2024] [Indexed: 03/22/2024] Open
Abstract
Proteins are considered magic molecules due to their enormous applications in the health sector. Over the past few decades, therapeutic proteins have emerged as a promising treatment option for various diseases, particularly cancer, cardiovascular disease, diabetes, and others. The formulation of protein-based therapies is a major area of research, however, a few factors still hinder the large-scale production of these therapeutic products, such as stability, heterogenicity, immunogenicity, high cost of production, etc. This review provides comprehensive information on various sources and production of therapeutic proteins. The review also summarizes the challenges currently faced by scientists while developing protein-based therapeutics, along with possible solutions. It can be concluded that these proteins can be used in combination with small molecular drugs to give synergistic benefits in the future.
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Affiliation(s)
- Vimal Kumar
- University Institute of Biotechnology, Chandigarh University, Gharuan, Mohali, Punjab 140413 India
| | - Arti Barwal
- Department of Microbial Biotechnology, Panjab University, South Campus, Sector-25, Chandigarh, 160014 India
| | - Nitin Sharma
- Department of Biotechnology, Chandigarh Group of Colleges, Mohali, Punjab 140307 India
| | - Danish Shafi Mir
- University Institute of Biotechnology, Chandigarh University, Gharuan, Mohali, Punjab 140413 India
| | - Pradeep Kumar
- Faculty of Applied Sciences and Biotechnology, Shoolini University of Biotechnology and Management Sciences, Solan, 173229 India
| | - Vikas Kumar
- University Institute of Biotechnology, Chandigarh University, Gharuan, Mohali, Punjab 140413 India
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14
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Bhatt B, García-Díaz P, Foight GW. Synthetic transcription factor engineering for cell and gene therapy. Trends Biotechnol 2024; 42:449-463. [PMID: 37865540 DOI: 10.1016/j.tibtech.2023.09.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 09/22/2023] [Accepted: 09/25/2023] [Indexed: 10/23/2023]
Abstract
Synthetic transcription factors (synTFs) that control beneficial transgene expression are an important method to increase the safety and efficacy of cell and gene therapy. Reliance on synTF components from non-human sources has slowed progress in the field because of concerns about immunogenicity and inducer drug properties. Recent advances in human-derived DNA-binding domains (DBDs) and transcriptional activation domains (TADs) paired with novel control modules responsive to clinically approved small molecules have poised the synTF field to overcome these hurdles. Advances include controllers inducible by autonomous signaling inputs and more complex, multi-input synTF circuits. Demonstrations of advanced control strategies with human-derived transcription factor components in clinically relevant vectors and in vivo models will facilitate progression into the clinic.
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Affiliation(s)
- Bhoomi Bhatt
- Center for Cell and Gene Therapy, Texas Children's Hospital, Houston Methodist Hospital, and Baylor College of Medicine, Houston, TX, USA
| | - Pablo García-Díaz
- Center for Cell and Gene Therapy, Texas Children's Hospital, Houston Methodist Hospital, and Baylor College of Medicine, Houston, TX, USA
| | - Glenna Wink Foight
- Center for Cell and Gene Therapy, Texas Children's Hospital, Houston Methodist Hospital, and Baylor College of Medicine, Houston, TX, USA; Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA.
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15
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Mock M, Langmead CJ, Grandsard P, Edavettal S, Russell A. Recent advances in generative biology for biotherapeutic discovery. Trends Pharmacol Sci 2024; 45:255-267. [PMID: 38378385 DOI: 10.1016/j.tips.2024.01.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 12/22/2023] [Accepted: 01/05/2024] [Indexed: 02/22/2024]
Abstract
Generative biology combines artificial intelligence (AI), advanced life sciences technologies, and automation to revolutionize the process of designing novel biomolecules with prescribed properties, giving drug discoverers the ability to escape the limitations of biology during the design of next-generation protein therapeutics. Significant hurdles remain, namely: (i) the inherently complex nature of drug discovery, (ii) the bewildering number of promising computational and experimental techniques that have emerged in the past several years, and (iii) the limited availability of relevant protein sequence-function data for drug-like molecules. There is a need to focus on computational methods that will be most practically effective for protein drug discovery and on building experimental platforms to generate the data most appropriate for these methods. Here, we discuss recent advances in computational and experimental life sciences that are most crucial for impacting the pace and success of protein drug discovery.
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Affiliation(s)
- Marissa Mock
- Amgen Research, Amgen Inc., One Amgen Center Drive, Thousand Oaks, CA 91320, USA
| | | | - Peter Grandsard
- Amgen Research, Amgen Inc., One Amgen Center Drive, Thousand Oaks, CA 91320, USA
| | - Suzanne Edavettal
- Amgen Research, Amgen Inc., One Amgen Center Drive, Thousand Oaks, CA 91320, USA
| | - Alan Russell
- Amgen Research, Amgen Inc., One Amgen Center Drive, Thousand Oaks, CA 91320, USA.
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16
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Lampe GD, King RT, Halpin-Healy TS, Klompe SE, Hogan MI, Vo PLH, Tang S, Chavez A, Sternberg SH. Targeted DNA integration in human cells without double-strand breaks using CRISPR-associated transposases. Nat Biotechnol 2024; 42:87-98. [PMID: 36991112 PMCID: PMC10620015 DOI: 10.1038/s41587-023-01748-1] [Citation(s) in RCA: 28] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 03/13/2023] [Indexed: 03/31/2023]
Abstract
Conventional genome engineering with CRISPR-Cas9 creates double-strand breaks (DSBs) that lead to undesirable byproducts and reduce product purity. Here we report an approach for programmable integration of large DNA sequences in human cells that avoids the generation of DSBs by using Type I-F CRISPR-associated transposases (CASTs). We optimized DNA targeting by the QCascade complex through protein design and developed potent transcriptional activators by exploiting the multi-valent recruitment of the AAA+ ATPase TnsC to genomic sites targeted by QCascade. After initial detection of plasmid-based integration, we screened 15 additional CAST systems from a wide range of bacterial hosts, identified a homolog from Pseudoalteromonas that exhibits improved activity and further increased integration efficiencies. Finally, we discovered that bacterial ClpX enhances genomic integration by multiple orders of magnitude, likely by promoting active disassembly of the post-integration CAST complex, akin to its known role in Mu transposition. Our work highlights the ability to reconstitute complex, multi-component machineries in human cells and establishes a strong foundation to exploit CRISPR-associated transposases for eukaryotic genome engineering.
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Affiliation(s)
- George D Lampe
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA
| | - Rebeca T King
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA
| | - Tyler S Halpin-Healy
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA
- Regeneron Pharmaceuticals, Inc., Tarrytown, NY, USA
| | - Sanne E Klompe
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA
- Department of Genomes and Genetics, Institut Pasteur, Paris, France
| | - Marcus I Hogan
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, USA
| | - Phuc Leo H Vo
- Department of Molecular Pharmacology and Therapeutics, Columbia University, New York, NY, USA
- Vertex Pharmaceuticals, Inc., Boston, MA, USA
| | - Stephen Tang
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA
| | - Alejandro Chavez
- Department of Pathology and Cell Biology, Columbia University, New York, NY, USA
- Department of Pediatrics, University of California, San Diego, La Jolla, CA, USA
| | - Samuel H Sternberg
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA.
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17
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Zhang C, Chang F, Miao H, Fu Y, Tong X, Feng Y, Zheng W, Ma X. Construction and application of a multifunctional CHO cell platform utilizing Cre/ lox and Dre/ rox site-specific recombination systems. Front Bioeng Biotechnol 2023; 11:1320841. [PMID: 38173869 PMCID: PMC10761530 DOI: 10.3389/fbioe.2023.1320841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Accepted: 12/04/2023] [Indexed: 01/05/2024] Open
Abstract
During the development of traditional Chinese hamster ovary (CHO) cell lines, target genes randomly integrate into the genome upon entering the nucleus, resulting in unpredictable productivity of cell clones. The characterization and screening of high-yielding cell lines is a time-consuming and expensive process. Site-specific integration is recognized as an effective approach for overcoming random integration and improving production stability. We have designed a multifunctional expression cassette, called CDbox, which can be manipulated by the site-specific recombination systems Cre/lox and Dre/rox. The CDbox expression cassette was inserted at the Hipp11(H11) locus hotspot in the CHO-K1 genome using CRISPR/Cas9 technology, and a compliant CHO-CDbox cell platform was screened and obtained. The CHO-CDbox cell platform was transformed into a pool of EGFP-expressing cells using Cre/lox recombinase-mediated cassette exchange (RMCE) in only 2 weeks, and this expression remained stable for at least 75 generations without the need for drug stress. Subsequently, we used the Dre/rox system to directly eliminate the EGFP gene. In addition, two practical applications of the CHO-CDbox cell platform were presented. The first was the quick construction of the Pembrolizumab antibody stable expression strain, while the second was a protocol for the integration of surface-displayed and secreted antibodies on CHO cells. The previous research on site-specific integration of CHO cells has always focused on the single functionality of insertion of target genes. This newly developed CHO cell platform is expected to offer expanded applicability for protein production and gene function studies.
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Affiliation(s)
- Chen Zhang
- State Key Laboratory of Bioreactor Engineering, School of Biotechnology, East China University of Science and Technology, Shanghai, China
| | - Feng Chang
- State Key Laboratory of Bioreactor Engineering, School of Biotechnology, East China University of Science and Technology, Shanghai, China
| | - Hui Miao
- State Key Laboratory of Bioreactor Engineering, School of Biotechnology, East China University of Science and Technology, Shanghai, China
| | - Yunhui Fu
- State Key Laboratory of Bioreactor Engineering, School of Biotechnology, East China University of Science and Technology, Shanghai, China
| | - Xikui Tong
- State Key Laboratory of Bioreactor Engineering, School of Biotechnology, East China University of Science and Technology, Shanghai, China
| | - Yu Feng
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, China
| | - Wenyun Zheng
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, China
| | - Xingyuan Ma
- State Key Laboratory of Bioreactor Engineering, School of Biotechnology, East China University of Science and Technology, Shanghai, China
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18
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Arbel-Groissman M, Menuhin-Gruman I, Naki D, Bergman S, Tuller T. Fighting the battle against evolution: designing genetically modified organisms for evolutionary stability. Trends Biotechnol 2023; 41:1518-1531. [PMID: 37442714 DOI: 10.1016/j.tibtech.2023.06.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 06/10/2023] [Accepted: 06/16/2023] [Indexed: 07/15/2023]
Abstract
Synthetic biology has made significant progress in many areas, but a major challenge that has received limited attention is the evolutionary stability of synthetic constructs made of heterologous genes. The expression of these constructs in microorganisms, that is, production of proteins that are not necessary for the organism, is a metabolic burden, leading to a decrease in relative fitness and make the synthetic constructs unstable over time. This is a significant concern for the synthetic biology community, particularly when it comes to bringing this technology out of the laboratory. In this review, we discuss the issue of evolutionary stability in synthetic biology and review the available tools to address this challenge.
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Affiliation(s)
- Matan Arbel-Groissman
- Shmunis School of Biomedicine and Cancer Research, The George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Itamar Menuhin-Gruman
- School of Mathematical Sciences, The Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Doron Naki
- Shmunis School of Biomedicine and Cancer Research, The George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Shaked Bergman
- Department of Biomedical Engineering, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Tamir Tuller
- Department of Biomedical Engineering, Tel Aviv University, Tel Aviv 6997801, Israel; The Sagol School of Neuroscience, Tel-Aviv University, Tel Aviv 6997801, Israel.
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19
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Roelle S, Kamath ND, Matreyek KA. Mammalian Genomic Manipulation with Orthogonal Bxb1 DNA Recombinase Sites for the Functional Characterization of Protein Variants. ACS Synth Biol 2023; 12:3352-3365. [PMID: 37922210 PMCID: PMC10661055 DOI: 10.1021/acssynbio.3c00355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2023] [Revised: 09/22/2023] [Accepted: 10/19/2023] [Indexed: 11/05/2023]
Abstract
The Bxb1 bacteriophage serine DNA recombinase is an efficient tool for engineering recombinant DNA into the genomes of cultured cells. Generally, a single engineered "landing pad" site is introduced into the cell genome, permitting the integration of transgenic circuits or libraries of transgene variants. While sufficient for many studies, the extent of genetic manipulation possible with a single recombinase site is limiting and insufficient for more complex cell-based assays. Here, we harnessed two orthogonal Bxb1 recombinase sites to enable alternative avenues for using mammalian synthetic biology to characterize transgenic protein variants. By designing plasmids flanked by a second pair of auxiliary recombination sites, we demonstrate that we can avoid the genomic integration of undesirable bacterial DNA elements using the same starting cells engineered for whole-plasmid integration. We also created "double landing pad" cells simultaneously harboring two orthogonal Bxb1 recombinase sites at separate genomic loci, allowing complex cell-based genetic assays. Integration of a genetically encoded calcium indicator allowed for the real-time monitoring of intracellular calcium signaling dynamics, including kinetic perturbations that occur upon overexpression of the wild-type or variant version of the calcium signaling relay protein STIM1. A panel of missense mutants of the HIV-1 accessory protein Vif was paired with various paralogs within the human Apobec3 innate immune protein family to identify combinations capable or incapable of interacting within cells. These cells allow transgenic protein variant libraries to be readily paired with assay-specific protein partners or biosensors, enabling new functional readouts for large-scale genetic assays for protein function.
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Affiliation(s)
- Sarah
M. Roelle
- Department of Pathology, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106, United States
| | - Nisha D. Kamath
- Department of Pathology, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106, United States
| | - Kenneth A. Matreyek
- Department of Pathology, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106, United States
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20
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Nguyen NTB, Leung HW, Pang KT, Tay SJ, Walsh I, Choo ABH, Yang Y. Optimizing effector functions of monoclonal antibodies via tailored N-glycan engineering using a dual landing pad CHO targeted integration platform. Sci Rep 2023; 13:15620. [PMID: 37731040 PMCID: PMC10511539 DOI: 10.1038/s41598-023-42925-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Accepted: 09/16/2023] [Indexed: 09/22/2023] Open
Abstract
Monoclonal antibodies (mAbs) eliminate cancer cells via various effector mechanisms including antibody-dependent cell-mediated cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC), which are influenced by the N-glycan structures on the Fc region of mAbs. Manipulating these glycan structures on mAbs allows for optimization of therapeutic benefits associated with effector functions. Traditional approaches such as gene deletion or overexpression often lead to only all-or-nothing changes in gene expression and fail to modulate the expression of multiple genes at defined ratios and levels. In this work, we have developed a CHO cell engineering platform enabling modulation of multiple gene expression to tailor the N-glycan profiles of mAbs for enhanced effector functions. Our platform involves a CHO targeted integration platform with two independent landing pads, allowing expression of multiple genes at two pre-determined genomic sites. By combining with internal ribosome entry site (IRES)-based polycistronic vectors, we simultaneously modulated the expression of α-mannosidase II (MANII) and chimeric β-1,4-N-acetylglucosaminyl-transferase III (cGNTIII) genes in CHO cells. This strategy enabled the production of mAbs carrying N-glycans with various levels of bisecting and non-fucosylated structures. Importantly, these engineered mAbs exhibited different degrees of effector cell activation and CDC, facilitating the identification of mAbs with optimal effector functions. This platform was demonstrated as a powerful tool for producing antibody therapeutics with tailored effector functions via precise engineering of N-glycan profiles. It holds promise for advancing the field of metabolic engineering in mammalian cells.
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Affiliation(s)
- Ngan T B Nguyen
- Bioprocessing Technology Institute (BTI), Agency for Science, Technology and Research (A*STAR), 20 Biopolis Way, #06-01 Centros, Singapore, 138668, Singapore
| | - Hau Wan Leung
- Bioprocessing Technology Institute (BTI), Agency for Science, Technology and Research (A*STAR), 20 Biopolis Way, #06-01 Centros, Singapore, 138668, Singapore
| | - Kuin Tian Pang
- Bioprocessing Technology Institute (BTI), Agency for Science, Technology and Research (A*STAR), 20 Biopolis Way, #06-01 Centros, Singapore, 138668, Singapore
| | - Shi Jie Tay
- Bioprocessing Technology Institute (BTI), Agency for Science, Technology and Research (A*STAR), 20 Biopolis Way, #06-01 Centros, Singapore, 138668, Singapore
| | - Ian Walsh
- Bioprocessing Technology Institute (BTI), Agency for Science, Technology and Research (A*STAR), 20 Biopolis Way, #06-01 Centros, Singapore, 138668, Singapore
| | - Andre B H Choo
- Bioprocessing Technology Institute (BTI), Agency for Science, Technology and Research (A*STAR), 20 Biopolis Way, #06-01 Centros, Singapore, 138668, Singapore
| | - Yuansheng Yang
- Bioprocessing Technology Institute (BTI), Agency for Science, Technology and Research (A*STAR), 20 Biopolis Way, #06-01 Centros, Singapore, 138668, Singapore.
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21
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Wauford N, Patel A, Tordoff J, Enghuus C, Jin A, Toppen J, Kemp ML, Weiss R. Synthetic symmetry breaking and programmable multicellular structure formation. Cell Syst 2023; 14:806-818.e5. [PMID: 37689062 PMCID: PMC10919224 DOI: 10.1016/j.cels.2023.08.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 04/14/2023] [Accepted: 08/02/2023] [Indexed: 09/11/2023]
Abstract
During development, cells undergo symmetry breaking into differentiated subpopulations that self-organize into complex structures.1,2,3,4,5 However, few tools exist to recapitulate these behaviors in a controllable and coupled manner.6,7,8,9 Here, we engineer a stochastic recombinase genetic switch tunable by small molecules to induce programmable symmetry breaking, commitment to downstream cell fates, and morphological self-organization. Inducers determine commitment probabilities, generating tunable subpopulations as a function of inducer dosage. We use this switch to control the cell-cell adhesion properties of cells committed to each fate.10,11 We generate a wide variety of 3D morphologies from a monoclonal population and develop a computational model showing high concordance with experimental results, yielding new quantitative insights into the relationship between cell-cell adhesion strengths and downstream morphologies. We expect that programmable symmetry breaking, generating precise and tunable subpopulation ratios and coupled to structure formation, will serve as an integral component of the toolbox for complex tissue and organoid engineering.
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Affiliation(s)
- Noreen Wauford
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Akshay Patel
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Jesse Tordoff
- Program in Computational and Systems Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Casper Enghuus
- Department of Microbiology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Andrew Jin
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - Jack Toppen
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, USA
| | - Melissa L Kemp
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - Ron Weiss
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA; Department of Electrical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.
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22
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Zhang M, Ehmann ME, Matukumalli S, Boob AG, Gilbert DM, Zhao H. SHIELD: a platform for high-throughput screening of barrier-type DNA elements in human cells. Nat Commun 2023; 14:5616. [PMID: 37699958 PMCID: PMC10497619 DOI: 10.1038/s41467-023-41468-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Accepted: 09/04/2023] [Indexed: 09/14/2023] Open
Abstract
Chromatin boundary elements contribute to the partitioning of mammalian genomes into topological domains to regulate gene expression. Certain boundary elements are adopted as DNA insulators for safe and stable transgene expression in mammalian cells. These elements, however, are ill-defined and less characterized in the non-coding genome, partially due to the lack of a platform to readily evaluate boundary-associated activities of putative DNA sequences. Here we report SHIELD (Site-specific Heterochromatin Insertion of Elements at Lamina-associated Domains), a platform tailored for the high-throughput screening of barrier-type DNA elements in human cells. SHIELD takes advantage of the high specificity of serine integrase at heterochromatin, and exploits the natural heterochromatin spreading inside lamina-associated domains (LADs) for the discovery of potent barrier elements. We adopt SHIELD to evaluate the barrier activity of 1000 DNA elements in a high-throughput manner and identify 8 candidates with barrier activities comparable to the core region of cHS4 element in human HCT116 cells. We anticipate SHIELD could facilitate the discovery of novel barrier DNA elements from the non-coding genome in human cells.
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Affiliation(s)
- Meng Zhang
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Mary Elisabeth Ehmann
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Srija Matukumalli
- Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Aashutosh Girish Boob
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - David M Gilbert
- San Diego Biomedical Research Institute, San Diego, CA, 92121, USA
| | - Huimin Zhao
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.
- Department of Chemistry, Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.
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23
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Bachhav B, de Rossi J, Llanos CD, Segatori L. Cell factory engineering: Challenges and opportunities for synthetic biology applications. Biotechnol Bioeng 2023; 120:2441-2459. [PMID: 36859509 PMCID: PMC10440303 DOI: 10.1002/bit.28365] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 02/14/2023] [Accepted: 02/27/2023] [Indexed: 03/03/2023]
Abstract
The production of high-quality recombinant proteins is critical to maintaining a continuous supply of biopharmaceuticals, such as therapeutic antibodies. Engineering mammalian cell factories presents a number of limitations typically associated with the proteotoxic stress induced upon aberrant accumulation of off-pathway protein folding intermediates, which eventually culminate in the induction of apoptosis. In this review, we will discuss advances in cell engineering and their applications at different hierarchical levels of control of the expression of recombinant proteins, from transcription and translational to posttranslational modifications and subcellular trafficking. We also highlight challenges and unique opportunities to apply modern synthetic biology tools to the design of programmable cell factories for improved biomanufacturing of therapeutic proteins.
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Affiliation(s)
- Bhagyashree Bachhav
- Department of Chemical and Biochemical Engineering, Rice University, Houston, United States
| | - Jacopo de Rossi
- Systems, Synthetic, and Physical Biology, Rice University, Houston, United States
| | - Carlos D. Llanos
- Systems, Synthetic, and Physical Biology, Rice University, Houston, United States
| | - Laura Segatori
- Department of Chemical and Biochemical Engineering, Rice University, Houston, United States
- Systems, Synthetic, and Physical Biology, Rice University, Houston, United States
- Department of Bioengineering, Rice University, Houston, United States
- Department of Biosciences, Rice University, Houston, United States
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24
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Milito A, Aschern M, McQuillan JL, Yang JS. Challenges and advances towards the rational design of microalgal synthetic promoters in Chlamydomonas reinhardtii. JOURNAL OF EXPERIMENTAL BOTANY 2023; 74:3833-3850. [PMID: 37025006 DOI: 10.1093/jxb/erad100] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Accepted: 03/24/2023] [Indexed: 06/19/2023]
Abstract
Microalgae hold enormous potential to provide a safe and sustainable source of high-value compounds, acting as carbon-fixing biofactories that could help to mitigate rapidly progressing climate change. Bioengineering microalgal strains will be key to optimizing and modifying their metabolic outputs, and to render them competitive with established industrial biotechnology hosts, such as bacteria or yeast. To achieve this, precise and tuneable control over transgene expression will be essential, which would require the development and rational design of synthetic promoters as a key strategy. Among green microalgae, Chlamydomonas reinhardtii represents the reference species for bioengineering and synthetic biology; however, the repertoire of functional synthetic promoters for this species, and for microalgae generally, is limited in comparison to other commercial chassis, emphasizing the need to expand the current microalgal gene expression toolbox. Here, we discuss state-of-the-art promoter analyses, and highlight areas of research required to advance synthetic promoter development in C. reinhardtii. In particular, we exemplify high-throughput studies performed in other model systems that could be applicable to microalgae, and propose novel approaches to interrogating algal promoters. We lastly outline the major limitations hindering microalgal promoter development, while providing novel suggestions and perspectives for how to overcome them.
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Affiliation(s)
- Alfonsina Milito
- Centre for Research in Agricultural Genomics (CRAG), CSIC-IRTA-UAB-UB, Campus UAB, Bellaterra, Barcelona, Spain
| | - Moritz Aschern
- Centre for Research in Agricultural Genomics (CRAG), CSIC-IRTA-UAB-UB, Campus UAB, Bellaterra, Barcelona, Spain
| | - Josie L McQuillan
- Department of Chemical and Biological Engineering, University of Sheffield, Mappin Street, Sheffield, S1 3JD, UK
| | - Jae-Seong Yang
- Centre for Research in Agricultural Genomics (CRAG), CSIC-IRTA-UAB-UB, Campus UAB, Bellaterra, Barcelona, Spain
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25
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Fatma Z, Tan SI, Boob AG, Zhao H. A landing pad system for multicopy gene integration in Issatchenkia orientalis. Metab Eng 2023; 78:200-208. [PMID: 37343658 DOI: 10.1016/j.ymben.2023.06.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 06/18/2023] [Accepted: 06/18/2023] [Indexed: 06/23/2023]
Abstract
The robust nature of the non-conventional yeast Issatchenkia orientalis allows it to grow under highly acidic conditions and therefore, has gained increasing interest in producing organic acids using a variety of carbon sources. Recently, the development of a genetic toolbox for I. orientalis, including an episomal plasmid, characterization of multiple promoters and terminators, and CRISPR-Cas9 tools, has eased the metabolic engineering efforts in I. orientalis. However, multiplex engineering is still hampered by the lack of efficient multicopy integration tools. To facilitate the construction of large, complex metabolic pathways by multiplex CRISPR-Cas9-mediated genome editing, we developed a bioinformatics pipeline to identify and prioritize genome-wide intergenic loci and characterized 47 gRNAs located in 21 intergenic regions. These loci are screened for guide RNA cutting efficiency, integration efficiency of a gene cassette, the resulting cellular fitness, and GFP expression level. We further developed a landing pad system using components from these well-characterized loci, which can aid in the integration of multiple genes using single guide RNA and multiple repair templates of the user's choice. We have demonstrated the use of the landing pad for simultaneous integrations of 2, 3, 4, or 5 genes to the target loci with efficiencies greater than 80%. As a proof of concept, we showed how the production of 5-aminolevulinic acid can be improved by integrating five copies of genes at multiple sites in one step. We have further demonstrated the efficiency of this tool by constructing a metabolic pathway for succinic acid production by integrating five gene expression cassettes using a single guide RNA along with five different repair templates, leading to the production of 9 g/L of succinic acid in batch fermentations. This study demonstrates the effectiveness of a single gRNA-mediated CRISPR platform to build complex metabolic pathways in a non-conventional yeast. This landing pad system will be a valuable tool for the metabolic engineering of I. orientalis.
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Affiliation(s)
- Zia Fatma
- Department of Chemical and Biomolecular Engineering, Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, United States
| | - Shih-I Tan
- Department of Chemical and Biomolecular Engineering, Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, United States
| | - Aashutosh Girish Boob
- Department of Chemical and Biomolecular Engineering, Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, United States
| | - Huimin Zhao
- Department of Chemical and Biomolecular Engineering, Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, United States; Departments of Chemistry, Biochemistry, and Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, United States.
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26
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Dehdilani N, Goshayeshi L, Yousefi Taemeh S, Bahrami AR, Rival Gervier S, Pain B, Dehghani H. Integrating Omics and CRISPR Technology for Identification and Verification of Genomic Safe Harbor Loci in the Chicken Genome. Biol Proced Online 2023; 25:18. [PMID: 37355580 DOI: 10.1186/s12575-023-00210-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Accepted: 06/02/2023] [Indexed: 06/26/2023] Open
Abstract
BACKGROUND One of the most prominent questions in the field of transgenesis is 'Where in the genome to integrate a transgene?'. Escape from epigenetic silencing and promoter shutdown of the transgene needs reliable genomic safe harbor (GSH) loci. Advances in genome engineering technologies combined with multi-omics bioinformatics data have enabled rational evaluation of GSH loci in the host genome. Currently, no validated GSH loci have been evaluated in the chicken genome. RESULTS Here, we analyzed and experimentally examined two GSH loci in the genome of chicken cells. To this end, putative GSH loci including chicken HIPP-like (cHIPP; between DRG1 and EIF4ENIF1 genes) and chicken ROSA-like (cROSA; upstream of the THUMPD3 gene) were predicted using multi-omics bioinformatics data. Then, the durable expression of the transgene was validated by experimental characterization of continuously-cultured isogenous cell clones harboring DsRed2-ΔCMV-EGFP cassette in the predicted loci. The weakened form of the CMV promoter (ΔCMV) allowed the precise evaluation of GSH loci in a locus-dependent manner compared to the full-length CMV promoter. CONCLUSIONS cHIPP and cROSA loci introduced in this study can be reliably exploited for consistent bio-manufacturing of recombinant proteins in the genetically-engineered chickens. Also, results showed that the genomic context dictates the expression of transgene controlled by ΔCMV in GSH loci.
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Affiliation(s)
- Nima Dehdilani
- Stem Cell Biology and Regenerative Medicine Research Group, Research Institute of Biotechnology, Ferdowsi University of Mashhad, Azadi Square, Mashhad, Iran
| | - Lena Goshayeshi
- Stem Cell Biology and Regenerative Medicine Research Group, Research Institute of Biotechnology, Ferdowsi University of Mashhad, Azadi Square, Mashhad, Iran
- Division of Biotechnology, Faculty of Veterinary Medicine, Ferdowsi University of Mashhad, Mashhad, Iran
| | - Sara Yousefi Taemeh
- Stem Cell Biology and Regenerative Medicine Research Group, Research Institute of Biotechnology, Ferdowsi University of Mashhad, Azadi Square, Mashhad, Iran
- Division of Biotechnology, Faculty of Veterinary Medicine, Ferdowsi University of Mashhad, Mashhad, Iran
| | - Ahmad Reza Bahrami
- Department of Biology, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, Iran
- Industrial Biotechnology Research Group, Institute of Biotechnology, Ferdowsi University of Mashhad, Mashhad, Iran
| | - Sylvie Rival Gervier
- Stem Cell and Brain Research Institute, University of Lyon, Université Lyon 1, INSERM, INRAE, U1208, USC1361, 69500, Bron, France
| | - Bertrand Pain
- Stem Cell and Brain Research Institute, University of Lyon, Université Lyon 1, INSERM, INRAE, U1208, USC1361, 69500, Bron, France
| | - Hesam Dehghani
- Stem Cell Biology and Regenerative Medicine Research Group, Research Institute of Biotechnology, Ferdowsi University of Mashhad, Azadi Square, Mashhad, Iran.
- Division of Biotechnology, Faculty of Veterinary Medicine, Ferdowsi University of Mashhad, Mashhad, Iran.
- Department of Basic Sciences, Faculty of Veterinary Medicine, Ferdowsi University of Mashhad, Mashhad, Iran.
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27
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Triassi AJ, Fields BD, Monahan CE, Means JM, Park Y, Doosthosseini H, Padmakumar JP, Isabella VM, Voigt CA. Redesign of an Escherichia coli Nissle treatment for phenylketonuria using insulated genomic landing pads and genetic circuits to reduce burden. Cell Syst 2023; 14:512-524.e12. [PMID: 37348465 DOI: 10.1016/j.cels.2023.05.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 01/18/2023] [Accepted: 05/19/2023] [Indexed: 06/24/2023]
Abstract
To build therapeutic strains, Escherichia coli Nissle (EcN) have been engineered to express antibiotics, toxin-degrading enzymes, immunoregulators, and anti-cancer chemotherapies. For efficacy, the recombinant genes need to be highly expressed, but this imposes a burden on the cell, and plasmids are difficult to maintain in the body. To address these problems, we have developed landing pads in the EcN genome and genetic circuits to control therapeutic gene expression. These tools were applied to EcN SYNB1618, undergoing clinical trials as a phenylketonuria treatment. The pathway for converting phenylalanine to trans-cinnamic acid was moved to a landing pad under the control of a circuit that keeps the pathway off during storage. The resulting strain (EcN SYN8784) achieved higher activity than EcN SYNB1618, reaching levels near when the pathway is carried on a plasmid. This work demonstrates a simple system for engineering EcN that aids quantitative strain design for therapeutics.
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Affiliation(s)
- Alexander J Triassi
- Synthetic Biology Center, Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Brandon D Fields
- Synthetic Biology Center, Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | | | | | - Yongjin Park
- Synthetic Biology Center, Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Hamid Doosthosseini
- Synthetic Biology Center, Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Jai P Padmakumar
- Synthetic Biology Center, Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | | | - Christopher A Voigt
- Synthetic Biology Center, Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
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28
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Fichter KM, Setayesh T, Malik P. Strategies for precise gene edits in mammalian cells. MOLECULAR THERAPY. NUCLEIC ACIDS 2023; 32:536-552. [PMID: 37215153 PMCID: PMC10192336 DOI: 10.1016/j.omtn.2023.04.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
CRISPR-Cas technologies have the potential to revolutionize genetic medicine. However, work is still needed to make this technology clinically efficient for gene correction. A barrier to making precise genetic edits in the human genome is controlling how CRISPR-Cas-induced DNA breaks are repaired by the cell. Since error-prone non-homologous end-joining is often the preferred cellular repair pathway, CRISPR-Cas-induced breaks often result in gene disruption. Homology-directed repair (HDR) makes precise genetic changes and is the clinically desired pathway, but this repair pathway requires a homology donor template and cycling cells. Newer editing strategies, such as base and prime editing, can affect precise repair for relatively small edits without requiring HDR and circumvent cell cycle dependence. However, these technologies have limitations in the extent of genetic editing and require the delivery of bulky cargo. Here, we discuss the pros and cons of precise gene correction using CRISPR-Cas-induced HDR, as well as base and prime editing for repairing small mutations. Finally, we consider emerging new technologies, such as recombination and transposases, which can circumvent both cell cycle and cellular DNA repair dependence for editing the genome.
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Affiliation(s)
- Katye M. Fichter
- Division of Experimental Hematology and Cancer Biology, Cancer and Blood Disease Institute, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Tahereh Setayesh
- Division of Experimental Hematology and Cancer Biology, Cancer and Blood Disease Institute, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Punam Malik
- Division of Experimental Hematology and Cancer Biology, Cancer and Blood Disease Institute, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH 45229, USA
- Division of Hematology, Cancer and Blood Disease Institute, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH 45229, USA
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29
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Huhtinen O, Salbo R, Lamminmäki U, Prince S. Selection of biophysically favorable antibody variants using a modified Flp-In CHO mammalian display platform. Front Bioeng Biotechnol 2023; 11:1170081. [PMID: 37229492 PMCID: PMC10203562 DOI: 10.3389/fbioe.2023.1170081] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Accepted: 04/17/2023] [Indexed: 05/27/2023] Open
Abstract
Mammalian display enables the selection of biophysically favorable antibodies from a large IgG antibody library displayed on the plasma membrane of mammalian cells. We constructed and validated a novel mammalian display platform utilizing the commercially available Flp-In CHO cell line as a starting point. We introduced a single copy of a landing pad for Bxb1 integrase-driven recombinase-mediated cassette exchange into the FRT site of the Flp-In CHO line to facilitate the efficient single-copy integration of an antibody display cassette into the genome of the cell line. We then proceeded to demonstrate the ability of our platform to select biophysically favorable antibodies from a library of 1 × 106 displayed antibodies designed to improve the biophysical properties of bococizumab via randomization of problematic hydrophobic surface residues of the antibody. Enrichment of bococizumab variants via fluorescence-activated cell sorting selections was followed by next generation sequencing and thorough characterization of biophysical properties of 10 bococizumab variants that subsequently allowed attribution of the mutations to the biophysical properties of the antibody variants. The mammalian displayed variants exhibited reduced aggregation propensity and polyreactivity, while critically retaining its target binding thereby demonstrating the utility of this valuable tool.
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Affiliation(s)
- Olli Huhtinen
- Protein and Antibody Engineering, Orion Corporation, Turku, Finland
- Department of Life Technologies, University of Turku, Turku, Finland
| | - Rune Salbo
- Protein and Antibody Engineering, Orion Corporation, Turku, Finland
| | - Urpo Lamminmäki
- Department of Life Technologies, University of Turku, Turku, Finland
| | - Stuart Prince
- MediCity Research Laboratory, University of Turku, Turku, Finland
- Institute of Biomedicine, University of Turku, Turku, Finland
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30
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Glinšek K, Bozovičar K, Bratkovič T. CRISPR Technologies in Chinese Hamster Ovary Cell Line Engineering. Int J Mol Sci 2023; 24:ijms24098144. [PMID: 37175850 PMCID: PMC10179654 DOI: 10.3390/ijms24098144] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Revised: 04/26/2023] [Accepted: 04/28/2023] [Indexed: 05/15/2023] Open
Abstract
The Chinese hamster ovary (CHO) cell line is a well-established platform for the production of biopharmaceuticals due to its ability to express complex therapeutic proteins with human-like glycopatterns in high amounts. The advent of CRISPR technology has opened up new avenues for the engineering of CHO cell lines for improved protein production and enhanced product quality. This review summarizes recent advances in the application of CRISPR technology for CHO cell line engineering with a particular focus on glycosylation modulation, productivity enhancement, tackling adventitious agents, elimination of problematic host cell proteins, development of antibiotic-free selection systems, site-specific transgene integration, and CRISPR-mediated gene activation and repression. The review highlights the potential of CRISPR technology in CHO cell line genome editing and epigenetic engineering for the more efficient and cost-effective development of biopharmaceuticals while ensuring the safety and quality of the final product.
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Affiliation(s)
- Katja Glinšek
- Faculty of Pharmacy, University of Ljubljana, Aškerčeva 7, 1000 Ljubljana, Slovenia
| | - Krištof Bozovičar
- Faculty of Pharmacy, University of Ljubljana, Aškerčeva 7, 1000 Ljubljana, Slovenia
| | - Tomaž Bratkovič
- Faculty of Pharmacy, University of Ljubljana, Aškerčeva 7, 1000 Ljubljana, Slovenia
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31
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Kalkan AK, Palaz F, Sofija S, Elmousa N, Ledezma Y, Cachat E, Rios-Solis L. Improving recombinant protein production in CHO cells using the CRISPR-Cas system. Biotechnol Adv 2023; 64:108115. [PMID: 36758652 DOI: 10.1016/j.biotechadv.2023.108115] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 12/28/2022] [Accepted: 02/03/2023] [Indexed: 02/10/2023]
Abstract
Chinese hamster ovary (CHO) cells are among the most widely used mammalian cell lines in the biopharmaceutical industry. Therefore, it is not surprising that significant efforts have been made around the engineering of CHO cells using genetic engineering methods such as the CRISPR-Cas system. In this review, we summarize key recent studies that have used different CRISPR-Cas systems such as Cas9, Cas13 or dCas9 fused with effector domains to improve recombinant protein (r-protein) production in CHO cells. Here, every relevant stage of production was considered, underscoring the advantages and limitations of these systems, as well as discussing their bottlenecks and probable solutions. A special emphasis was given on how these systems could disrupt and/or regulate genes related to glycan composition, which has relevant effects over r-protein properties and in vivo activity. Furthermore, the related promising future applications of CRISPR to achieve a tunable, reversible, or highly stable editing of CHO cells are discussed. Overall, the studies covered in this review show that despite the complexity of mammalian cells, the synthetic biology community has developed many mature strategies to improve r-protein production using CHO cells. In this regard, CRISPR-Cas technology clearly provides efficient and flexible genetic manipulation and allows for the generation of more productive CHO cell lines, leading to more cost-efficient production of biopharmaceuticals, however, there is still a need for many emerging techniques in CRISPR to be reported in CHO cells; therefore, more research in these cells is needed to realize the full potential of this technology.
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Affiliation(s)
- Ali Kerem Kalkan
- Department of Bioengineering and Imperial College Centre for Synthetic Biology, Imperial College London, London, UK; Environmental Engineering Department, Gebze Technical University, Turkey
| | - Fahreddin Palaz
- Faculty of Medicine, Hacettepe University, Ankara 06100, Turkey
| | - Semeniuk Sofija
- Centre for Engineering Biology, University of Edinburgh, Edinburgh EH9 3BF, UK; Institute of Quantitative Biology, Biochemistry and Biotechnology, School of Biological Sciences University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Nada Elmousa
- Institute for Bioengineering, School of Engineering, University of Edinburgh, Edinburgh EH9 3DW, UK
| | - Yuri Ledezma
- Institute for Bioengineering, School of Engineering, University of Edinburgh, Edinburgh EH9 3DW, UK; Biology Department, Faculty of Pure and Natural Sciences, Universidad Mayor de San Andrés, Bolivia
| | - Elise Cachat
- Centre for Engineering Biology, University of Edinburgh, Edinburgh EH9 3BF, UK; Institute of Quantitative Biology, Biochemistry and Biotechnology, School of Biological Sciences University of Edinburgh, Edinburgh EH9 3BF, UK; UK Centre for Mammalian Synthetic Biology, University of Edinburgh, Edinburgh EH8 9YL, UK
| | - Leonardo Rios-Solis
- Centre for Engineering Biology, University of Edinburgh, Edinburgh EH9 3BF, UK; Institute for Bioengineering, School of Engineering, University of Edinburgh, Edinburgh EH9 3DW, UK; School of Natural and Environmental Sciences, Molecular Biology and Biotechnology Division, Newcastle University, Newcastle Upon Tyne, NE1 7RU, UK.
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32
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Jerez-Longres C, Gómez-Matos M, Becker J, Hörner M, Wieland FG, Timmer J, Weber W. Engineering a material-genetic interface as safety switch for embedded therapeutic cells. BIOMATERIALS ADVANCES 2023; 150:213422. [PMID: 37084636 DOI: 10.1016/j.bioadv.2023.213422] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Revised: 03/28/2023] [Accepted: 04/04/2023] [Indexed: 04/23/2023]
Abstract
Encapsulated cell-based therapies involve the use of genetically-modified cells embedded in a material in order to produce a therapeutic agent in a specific location in the patient's body. This approach has shown great potential in animal model systems for treating diseases such as type I diabetes or cancer, with selected approaches having been tested in clinical trials. Despite the promise shown by encapsulated cell therapy, though, there are safety concerns yet to be addressed, such as the escape of the engineered cells from the encapsulation material and the resulting production of therapeutic agents at uncontrolled sites in the body. For that reason, there is great interest in the implementation of safety switches that protect from those side effects. Here, we develop a material-genetic interface as safety switch for engineered mammalian cells embedded into hydrogels. Our switch allows the therapeutic cells to sense whether they are embedded in the hydrogel by means of a synthetic receptor and signaling cascade that link transgene expression to the presence of an intact embedding material. The system design is highly modular, allowing its flexible adaptation to other cell types and embedding materials. This autonomously acting switch constitutes an advantage over previously described safety switches, which rely on user-triggered signals to modulate activity or survival of the implanted cells. We envision that the concept developed here will advance the safety of cell therapies and facilitate their translation to clinical evaluation.
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Affiliation(s)
- Carolina Jerez-Longres
- Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Schänzlestrasse 18, 79104 Freiburg, Germany; Faculty of Biology, University of Freiburg, Schänzlestrasse 1, 79104 Freiburg, Germany; SGBM - Spemann Graduate School of Biology and Medicine, University of Freiburg, Albertstrasse 19a, 79104 Freiburg, Germany
| | - Marieta Gómez-Matos
- Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Schänzlestrasse 18, 79104 Freiburg, Germany; Faculty of Biology, University of Freiburg, Schänzlestrasse 1, 79104 Freiburg, Germany
| | - Jan Becker
- Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Schänzlestrasse 18, 79104 Freiburg, Germany; Faculty of Biology, University of Freiburg, Schänzlestrasse 1, 79104 Freiburg, Germany
| | - Maximilian Hörner
- Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Schänzlestrasse 18, 79104 Freiburg, Germany; Faculty of Biology, University of Freiburg, Schänzlestrasse 1, 79104 Freiburg, Germany
| | - Franz-Georg Wieland
- Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Schänzlestrasse 18, 79104 Freiburg, Germany; Institute of Physics, University of Freiburg, Hermann-Herder-Strasse 3, 79104 Freiburg, Germany; Freiburg Center for Data Analysis and Modelling (FDM), University of Freiburg, Ernst-Zermelo-Strasse 1, 79104 Freiburg, Germany
| | - Jens Timmer
- Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Schänzlestrasse 18, 79104 Freiburg, Germany; Institute of Physics, University of Freiburg, Hermann-Herder-Strasse 3, 79104 Freiburg, Germany; Freiburg Center for Data Analysis and Modelling (FDM), University of Freiburg, Ernst-Zermelo-Strasse 1, 79104 Freiburg, Germany
| | - Wilfried Weber
- INM - Leibniz Institute for New Materials, Campus D2 2, 66123 Saarbrücken, Germany; Department of Materials Science and Materials Engineering, Saarland University, 66123 Saarbrücken, Germany; Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Schänzlestrasse 18, 79104 Freiburg, Germany; Faculty of Biology, University of Freiburg, Schänzlestrasse 1, 79104 Freiburg, Germany; SGBM - Spemann Graduate School of Biology and Medicine, University of Freiburg, Albertstrasse 19a, 79104 Freiburg, Germany.
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33
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Amiri S, Adibzadeh S, Ghanbari S, Rahmani B, Kheirandish MH, Farokhi-Fard A, Dastjerdeh MS, Davami F. CRISPR-interceded CHO cell line development approaches. Biotechnol Bioeng 2023; 120:865-902. [PMID: 36597180 DOI: 10.1002/bit.28329] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Revised: 11/28/2022] [Accepted: 01/02/2023] [Indexed: 01/05/2023]
Abstract
For industrial production of recombinant protein biopharmaceuticals, Chinese hamster ovary (CHO) cells represent the most widely adopted host cell system, owing to their capacity to produce high-quality biologics with human-like posttranslational modifications. As opposed to random integration, targeted genome editing in genomic safe harbor sites has offered CHO cell line engineering a new perspective, ensuring production consistency in long-term culture and high biotherapeutic expression levels. Corresponding the remarkable advancements in knowledge of CRISPR-Cas systems, the use of CRISPR-Cas technology along with the donor design strategies has been pushed into increasing novel scenarios in cell line engineering, allowing scientists to modify mammalian genomes such as CHO cell line quickly, readily, and efficiently. Depending on the strategies and production requirements, the gene of interest can also be incorporated at single or multiple loci. This review will give a gist of all the most fundamental recent advancements in CHO cell line development, such as different cell line engineering approaches along with donor design strategies for targeted integration of the desired construct into genomic hot spots, which could ultimately lead to the fast-track product development process with consistent, improved product yield and quality.
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Affiliation(s)
- Shahin Amiri
- Department of Medical Biotechnology, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran
| | - Setare Adibzadeh
- Department of Medical Biotechnology, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran
| | - Samaneh Ghanbari
- Department of Medical Biotechnology, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran
| | - Behnaz Rahmani
- Department of Medical Biotechnology, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran
| | - Mohammad H Kheirandish
- Department of Medical Biotechnology, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran
- Department of Medical Biotechnology, School of Advanced Technologies, Tehran University of Medical Sciences, Tehran, Iran
| | - Aref Farokhi-Fard
- Department of Medical Biotechnology, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran
| | - Mansoureh S Dastjerdeh
- Department of Medical Biotechnology, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran
| | - Fatemeh Davami
- Department of Medical Biotechnology, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran
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Lampe GD, King RT, Halpin-Healy TS, Klompe SE, Hogan MI, Vo PLH, Tang S, Chavez A, Sternberg SH. Targeted DNA integration in human cells without double-strand breaks using CRISPR RNA-guided transposases. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.17.533036. [PMID: 36993517 PMCID: PMC10055298 DOI: 10.1101/2023.03.17.533036] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Traditional genome-editing reagents such as CRISPR-Cas9 achieve targeted DNA modification by introducing double-strand breaks (DSBs), thereby stimulating localized DNA repair by endogenous cellular repair factors. While highly effective at generating heterogenous knockout mutations, this approach suffers from undesirable byproducts and an inability to control product purity. Here we develop a system in human cells for programmable, DSB-free DNA integration using Type I CRISPR-associated transposons (CASTs). To adapt our previously described CAST systems, we optimized DNA targeting by the QCascade complex through a comprehensive assessment of protein design, and we developed potent transcriptional activators by exploiting the multi-valent recruitment of the AAA+ ATPase, TnsC, to genomic sites targeted by QCascade. After initial detection of plasmid-based transposition, we screened 15 homologous CAST systems from a wide range of bacterial hosts, identified a CAST homolog from Pseudoalteromonas that exhibited improved activity, and increased integration efficiencies through parameter optimization. We further discovered that bacterial ClpX enhances genomic integration by multiple orders of magnitude, and we propose that this critical accessory factor functions to drive active disassembly of the post-transposition CAST complex, akin to its demonstrated role in Mu transposition. Our work highlights the ability to functionally reconstitute complex, multi-component machineries in human cells, and establishes a strong foundation to realize the full potential of CRISPR-associated transposons for human genome engineering.
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Affiliation(s)
- George D Lampe
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA
| | - Rebeca T King
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA
| | - Tyler S Halpin-Healy
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA
| | - Sanne E Klompe
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA
| | - Marcus I Hogan
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA
| | - Phuc Leo H Vo
- Department of Molecular Pharmacology and Therapeutics, Columbia University, New York, NY, USA
| | - Stephen Tang
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA
| | - Alejandro Chavez
- Department of Pathology and Cell Biology, Columbia University, New York, NY, USA
| | - Samuel H Sternberg
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA
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Abstract
Ubiquitously expressed throughout the body, ATP-sensitive potassium (KATP) channels couple cellular metabolism to electrical activity in multiple tissues; their unique assembly as four Kir6 pore-forming subunits and four sulfonylurea receptor (SUR) subunits has resulted in a large armory of selective channel opener and inhibitor drugs. The spectrum of monogenic pathologies that result from gain- or loss-of-function mutations in these channels, and the potential for therapeutic correction of these pathologies, is now clear. However, while available drugs can be effective treatments for specific pathologies, cross-reactivity with the other Kir6 or SUR subfamily members can result in drug-induced versions of each pathology and may limit therapeutic usefulness. This review discusses the background to KATP channel physiology, pathology, and pharmacology and considers the potential for more specific or effective therapeutic agents.
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Affiliation(s)
- Colin G. Nichols
- Center for the Investigation of Membrane Excitability Diseases and Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri, USA
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36
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Targeted integration in CHO cells using CRIS-PITCh/Bxb1 recombinase-mediated cassette exchange hybrid system. Appl Microbiol Biotechnol 2023; 107:769-783. [PMID: 36536089 PMCID: PMC9763083 DOI: 10.1007/s00253-022-12322-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 11/27/2022] [Accepted: 11/30/2022] [Indexed: 12/24/2022]
Abstract
Recombinant Chinese hamster ovary (CHO) cell line development for complex biotherapeutic production is conventionally based on the random integration (RI) approach. Due to the lack of control over the integration site and copy number, RI-generated cell pools are always coupled with rigorous screening to find clones that satisfy requirements for production titers, quality, and stability. Targeted integration into a well-defined genomic site has been suggested as a possible strategy to mitigate the drawbacks associated with RI. In this work, we employed the CRISPR-mediated precise integration into target chromosome (CRIS-PITCh) system in combination with the Bxb1 recombinase-mediated cassette exchange (RMCE) system to generate an isogenic transgene-expressing cell line. We successfully utilized the CRIS-PITCh system to target a 2.6 kb Bxb1 landing pad with homology arms as short as 30 bp into the upstream region of the S100A gene cluster, achieving a targeting efficiency of 10.4%. The platform cell line (PCL) with a single copy of the landing pad was then employed for the Bxb1-mediated landing pad exchange with an EGFP encoding cassette to prove its functionality. Finally, to accomplish the main goal of our cell line development method, the PCL was applied for the expression of a secretory glycoprotein, human recombinant soluble angiotensin-converting enzyme 2 (hrsACE2). Taken together, on-target, single-copy, and stable expression of the transgene over long-term cultivation demonstrated our CRIS-PITCh/RMCE hybrid approach might possibly improve the cell line development process in terms of timeline, specificity, and stability. KEY POINTS: • CRIS-PITCh system is an efficient method for single copy targeted integration of the landing pad and generation of platform cell line • Upstream region of the S100A gene cluster of CHO-K1 is retargetable by recombinase-mediated cassette exchange (RMCE) approach and provides a stable expression of the transgene • CRIS-PITCh/Bxb1 RMCE hybrid system has the potential to overcome some limitations of the random integration approach and accelerate the cell line development timeline.
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37
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Oliviero C, Hinz SC, Grzeschik J, Hock B, Kolmar H, Hagens G. Cell Line Development Using Targeted Gene Integration into MAR-Rich Landing Pads for Stable Expression of Transgenes. Methods Mol Biol 2023; 2681:343-359. [PMID: 37405657 DOI: 10.1007/978-1-0716-3279-6_19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/06/2023]
Abstract
Integration of a gene of interest (GOI) into the genome of mammalian cells is the first step of cell line development campaigns for the production of biotherapeutics. Besides random integration methods, targeted gene integration approaches have emerged as promising tools over the last few years. In addition to reducing heterogeneity within a pool of recombinant transfectants, this process can also facilitate shorter timelines of the current cell line development process. Herein, we describe protocols for generating host cell lines carrying matrix attachment region (MAR)-rich landing pads (LPs), including BxB1 recombination sites. These LP-containing cell lines allow for site-specific and simultaneous integration of multiple GOIs. The resulting transgene-expressing stable recombinant clones can be used for the production of mono- or multispecific antibodies.
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Affiliation(s)
- Claudia Oliviero
- Institute of Life Technologies, Haute Ecole d'Ingénierie HES-SO Valais Wallis, Sion, Switzerland
| | - Steffen C Hinz
- Institute of Life Technologies, Haute Ecole d'Ingénierie HES-SO Valais Wallis, Sion, Switzerland
| | | | - Björn Hock
- Aerium Therapeutics, Epalinges, Switzerland
| | - Harald Kolmar
- Institute for Organic Chemistry and Biochemistry, Technische Universität Darmstadt, Darmstadt, Germany
| | - Gerrit Hagens
- Institute of Life Technologies, Haute Ecole d'Ingénierie HES-SO Valais Wallis, Sion, Switzerland.
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38
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Daboussi F, Lindley ND. Challenges to Ensure a Better Translation of Metabolic Engineering for Industrial Applications. Methods Mol Biol 2023; 2553:1-20. [PMID: 36227536 DOI: 10.1007/978-1-0716-2617-7_1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Metabolic engineering has evolved towards creating cell factories with increasingly complex pathways as economic criteria push biotechnology to higher value products to provide a sustainable source of speciality chemicals. Optimization of such pathways often requires high combinatory exploration of best pathway balance, and this has led to increasing use of high-throughput automated strain construction platforms or novel optimization techniques. In addition, the low catalytic efficiency of such pathways has shifted emphasis from gene expression strategies towards novel protein engineering to increase specific activity of the enzymes involved so as to limit the metabolic burden associated with excessively high pressure on ribosomal machinery when using massive overexpression systems. Metabolic burden is now generally recognized as a major hurdle to be overcome with consequences on genetic stability but also on the intensified performance needed industrially to attain the economic targets for successful product launch. Increasing awareness of the need to integrate novel genetic information into specific sites within the genome which not only enhance genetic stability (safe harbors) but also enable maximum expression profiles has led to genome-wide assessment of best integration sites, and bioinformatics will facilitate the identification of most probable landing pads within the genome.To facilitate the transfer of novel biotechnological potential to industrial-scale production, more attention, however, has to be paid to engineering metabolic fitness adapted to the specific stress conditions inherent to large-scale fermentation and the inevitable heterogeneity that will occur due to mass transfer limitations and the resulting deviation away from ideal conditions as seen in laboratory-scale validation of the engineered cells. To ensure smooth and rapid transfer of novel cell lines to industry with an accelerated passage through scale-up, better coordination is required form the onset between the biochemical engineers involved in process technology and the genetic engineers building the new strain so as to have an overall strategy able to maximize innovation at all levels. This should be one of our key objectives when building fermentation-friendly chassis organisms.
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Affiliation(s)
- Fayza Daboussi
- Toulouse White Biotechnology, Toulouse cedex 4, France
- Toulouse Biotechnology Institute, Toulouse cedex 4, France
| | - Nic D Lindley
- Toulouse White Biotechnology, Toulouse cedex 4, France.
- Toulouse Biotechnology Institute, Toulouse cedex 4, France.
- ASTAR Singapore Institute of Food and Biotechnology Innovation (SIFBI), Singapore, Singapore.
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39
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Cabrera A, Edelstein HI, Glykofrydis F, Love KS, Palacios S, Tycko J, Zhang M, Lensch S, Shields CE, Livingston M, Weiss R, Zhao H, Haynes KA, Morsut L, Chen YY, Khalil AS, Wong WW, Collins JJ, Rosser SJ, Polizzi K, Elowitz MB, Fussenegger M, Hilton IB, Leonard JN, Bintu L, Galloway KE, Deans TL. The sound of silence: Transgene silencing in mammalian cell engineering. Cell Syst 2022; 13:950-973. [PMID: 36549273 PMCID: PMC9880859 DOI: 10.1016/j.cels.2022.11.005] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 09/22/2022] [Accepted: 11/22/2022] [Indexed: 12/24/2022]
Abstract
To elucidate principles operating in native biological systems and to develop novel biotechnologies, synthetic biology aims to build and integrate synthetic gene circuits within native transcriptional networks. The utility of synthetic gene circuits for cell engineering relies on the ability to control the expression of all constituent transgene components. Transgene silencing, defined as the loss of expression over time, persists as an obstacle for engineering primary cells and stem cells with transgenic cargos. In this review, we highlight the challenge that transgene silencing poses to the robust engineering of mammalian cells, outline potential molecular mechanisms of silencing, and present approaches for preventing transgene silencing. We conclude with a perspective identifying future research directions for improving the performance of synthetic gene circuits.
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Affiliation(s)
- Alan Cabrera
- Department of Bioengineering, Rice University, Houston, TX 77005, USA; Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Hailey I Edelstein
- Center for Synthetic Biology, Northwestern University, Evanston, IL 60208, USA; The Eli and Edythe Broad CIRM Center, Department of Chemical and Biological Engineering, Northwestern University, Evanston, IL 60208, USA
| | - Fokion Glykofrydis
- Department of Stem Cell Biology and Regenerative Medicine, University of Southern California, Los Angeles, CA 90033-9080, USA
| | - Kasey S Love
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Sebastian Palacios
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Josh Tycko
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Meng Zhang
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Champaign, Urbana, IL 61801, USA
| | - Sarah Lensch
- Department of Bioengineering, Stanford University, Stanford, CA 94305, USA
| | - Cara E Shields
- Wallace H. Coulter Department of Biomedical Engineering, Emory University, Atlanta, GA 30322, USA
| | - Mark Livingston
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT 84112, USA
| | - Ron Weiss
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Huimin Zhao
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Champaign, Urbana, IL 61801, USA
| | - Karmella A Haynes
- Wallace H. Coulter Department of Biomedical Engineering, Emory University, Atlanta, GA 30322, USA
| | - Leonardo Morsut
- Department of Stem Cell Biology and Regenerative Medicine, University of Southern California, Los Angeles, CA 90033-9080, USA
| | - Yvonne Y Chen
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA; Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, Los Angeles, CA 90095, USA; Parker Institute for Cancer Immunotherapy Center at UCLA, Los Angeles, CA 90095, USA
| | - Ahmad S Khalil
- Biological Design Center and Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA; Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, USA
| | - Wilson W Wong
- Biological Design Center and Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA
| | - James J Collins
- Department of Stem Cell Biology and Regenerative Medicine, University of Southern California, Los Angeles, CA 90033-9080, USA; Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, USA; Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, USA; Harvard-MIT Program in Health Sciences and Technology, Cambridge, MA 02139, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02139, USA
| | - Susan J Rosser
- School of Biological Sciences, University of Edinburgh, Edinburgh, UK
| | - Karen Polizzi
- Department of Chemical Engineering, Imperial College London, South Kensington Campus, London, UK; Imperial College Centre for Synthetic Biology, South Kensington Campus, London, UK
| | - Michael B Elowitz
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA; Howard Hughes Medical Institute, California Institute of Technology, Pasadena, CA 91125, USA
| | - Martin Fussenegger
- Department of Biosystems Science and Engineering, ETH Zurich, Mattenstrasse 26, Basel 4058, Switzerland; Faculty of Science, University of Basel, Mattenstrasse 26, Basel 4058, Switzerland
| | - Isaac B Hilton
- Department of Bioengineering, Rice University, Houston, TX 77005, USA
| | - Joshua N Leonard
- Center for Synthetic Biology, Northwestern University, Evanston, IL 60208, USA; The Eli and Edythe Broad CIRM Center, Department of Chemical and Biological Engineering, Northwestern University, Evanston, IL 60208, USA
| | - Lacramioara Bintu
- Department of Bioengineering, Stanford University, Stanford, CA 94305, USA
| | - Kate E Galloway
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Tara L Deans
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT 84112, USA.
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40
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Blanch-Asensio A, Grandela C, Brandão KO, de Korte T, Mei H, Ariyurek Y, Yiangou L, Mol MP, van Meer BJ, Kloet SL, Mummery CL, Davis RP. STRAIGHT-IN enables high-throughput targeting of large DNA payloads in human pluripotent stem cells. CELL REPORTS METHODS 2022; 2:100300. [PMID: 36313798 PMCID: PMC9606106 DOI: 10.1016/j.crmeth.2022.100300] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 07/12/2022] [Accepted: 08/31/2022] [Indexed: 04/20/2023]
Abstract
Inserting large DNA payloads (>10 kb) into specific genomic sites of mammalian cells remains challenging. Applications ranging from synthetic biology to evaluating the pathogenicity of disease-associated variants for precision medicine initiatives would greatly benefit from tools that facilitate this process. Here, we merge the strengths of different classes of site-specific recombinases and combine these with CRISPR-Cas9-mediated homologous recombination to develop a strategy for stringent site-specific replacement of genomic fragments at least 50 kb in size in human induced pluripotent stem cells (hiPSCs). We demonstrate the versatility of STRAIGHT-IN (serine and tyrosine recombinase-assisted integration of genes for high-throughput investigation) by (1) inserting various combinations of fluorescent reporters into hiPSCs to assess the excitation-contraction coupling cascade in derivative cardiomyocytes and (2) simultaneously targeting multiple variants associated with inherited cardiac arrhythmic disorders into a pool of hiPSCs. STRAIGHT-IN offers a precise approach to generate genetically matched panels of hiPSC lines efficiently and cost effectively.
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Affiliation(s)
- Albert Blanch-Asensio
- Department of Anatomy and Embryology, Leiden University Medical Center, 2300RC Leiden, the Netherlands
| | - Catarina Grandela
- Department of Anatomy and Embryology, Leiden University Medical Center, 2300RC Leiden, the Netherlands
| | - Karina O. Brandão
- Department of Anatomy and Embryology, Leiden University Medical Center, 2300RC Leiden, the Netherlands
| | - Tessa de Korte
- Department of Anatomy and Embryology, Leiden University Medical Center, 2300RC Leiden, the Netherlands
| | - Hailiang Mei
- Sequencing Analysis Support Core, Leiden University Medical Center, 2333RC Leiden, the Netherlands
| | - Yavuz Ariyurek
- Leiden Genome Technology Center, Leiden University Medical Center, 2333RC Leiden, the Netherlands
| | - Loukia Yiangou
- Department of Anatomy and Embryology, Leiden University Medical Center, 2300RC Leiden, the Netherlands
| | - Mervyn P.H. Mol
- Department of Anatomy and Embryology, Leiden University Medical Center, 2300RC Leiden, the Netherlands
| | - Berend J. van Meer
- Department of Anatomy and Embryology, Leiden University Medical Center, 2300RC Leiden, the Netherlands
| | - Susan L. Kloet
- Leiden Genome Technology Center, Leiden University Medical Center, 2333RC Leiden, the Netherlands
| | - Christine L. Mummery
- Department of Anatomy and Embryology, Leiden University Medical Center, 2300RC Leiden, the Netherlands
- Department of Applied Stem Cell Technologies, University of Twente, 7500AE Enschede, the Netherlands
| | - Richard P. Davis
- Department of Anatomy and Embryology, Leiden University Medical Center, 2300RC Leiden, the Netherlands
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41
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Chen WCW, Gaidukov L, Lai Y, Wu MR, Cao J, Gutbrod MJ, Choi GCG, Utomo RP, Chen YC, Wroblewska L, Kellis M, Zhang L, Weiss R, Lu TK. A synthetic transcription platform for programmable gene expression in mammalian cells. Nat Commun 2022; 13:6167. [PMID: 36257931 PMCID: PMC9579178 DOI: 10.1038/s41467-022-33287-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Accepted: 09/13/2022] [Indexed: 12/24/2022] Open
Abstract
Precise, scalable, and sustainable control of genetic and cellular activities in mammalian cells is key to developing precision therapeutics and smart biomanufacturing. Here we create a highly tunable, modular, versatile CRISPR-based synthetic transcription system for the programmable control of gene expression and cellular phenotypes in mammalian cells. Genetic circuits consisting of well-characterized libraries of guide RNAs, binding motifs of synthetic operators, transcriptional activators, and additional genetic regulatory elements express mammalian genes in a highly predictable and tunable manner. We demonstrate the programmable control of reporter genes episomally and chromosomally, with up to 25-fold more activity than seen with the EF1α promoter, in multiple cell types. We use these circuits to program the secretion of human monoclonal antibodies and to control T-cell effector function marked by interferon-γ production. Antibody titers and interferon-γ concentrations significantly correlate with synthetic promoter strengths, providing a platform for programming gene expression and cellular function in diverse applications.
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Affiliation(s)
- William C W Chen
- Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
- Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
- Cardiovascular Research Center, Massachusetts General Hospital, Boston, MA, 02114, USA.
- Division of Basic Biomedical Sciences, Sanford School of Medicine, University of South Dakota, Vermillion, SD, 57069, USA.
| | - Leonid Gaidukov
- Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Yong Lai
- Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Ming-Ru Wu
- Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA, 02215, USA
| | - Jicong Cao
- Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Michael J Gutbrod
- Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Broad Institute of Massachusetts Institute of Technology and Harvard University, Cambridge, MA, 02139, USA
| | - Gigi C G Choi
- Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Laboratory of Combinatorial Genetics and Synthetic Biology, School of Biomedical Sciences, The University of Hong Kong, Hong Kong, China
| | - Rachel P Utomo
- Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Department of Biochemistry, Wellesley College, Wellesley, MA, 02481, USA
| | - Ying-Chou Chen
- Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei, Taiwan
| | | | - Manolis Kellis
- Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Broad Institute of Massachusetts Institute of Technology and Harvard University, Cambridge, MA, 02139, USA
| | - Lin Zhang
- Pfizer Inc., Andover, MA, 01810, USA
| | - Ron Weiss
- Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Timothy K Lu
- Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
- Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
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42
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Hertel O, Neuss A, Busche T, Brandt D, Kalinowski J, Bahnemann J, Noll T. Enhancing stability of recombinant CHO cells by CRISPR/Cas9-mediated site-specific integration into regions with distinct histone modifications. Front Bioeng Biotechnol 2022; 10:1010719. [PMID: 36312557 PMCID: PMC9606416 DOI: 10.3389/fbioe.2022.1010719] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Accepted: 09/30/2022] [Indexed: 11/24/2022] Open
Abstract
Chinese hamster ovary (CHO) cells are the most important platform for producing biotherapeutics. Random integration of a transgene into epigenetically instable regions of the genome results in silencing of the gene of interest and loss of productivity during upstream processing. Therefore, cost- and time-intensive long-term stability studies must be performed. Site-specific integration into safe harbors is a strategy to overcome these limitations of conventional cell line design. Recent publications predict safe harbors in CHO cells based on omics data sets or by learning from random integrations, but those predictions remain theory. In this study, we established a CRISPR/Cas9-mediated site-specific integration strategy based on ChIP-seq data to improve stability of recombinant CHO cells. Therefore, a ChIP experiment from the exponential and stationary growth phase of a fed-batch cultivation of CHO-K1 cells yielded 709 potentially stable integration sites. The reporter gene eGFP was integrated into three regions harboring specific modifications by CRISPR/Cas9. Targeted Cas9 nanopore sequencing showed site-specific integration in all 3 cell pools with a specificity between 23 and 73%. Subsequently, the cells with the three different integration sites were compared with the randomly integrated donor vector in terms of transcript level, productivity, gene copy numbers and stability. All site-specific integrations showed an increase in productivity and transcript levels of up to 7.4-fold. In a long-term cultivation over 70 generations, two of the site-specific integrations showed a stable productivity (>70%) independent of selection pressure.
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Affiliation(s)
- Oliver Hertel
- Cell Culture Technology, Faculty of Technology, Bielefeld University, Bielefeld, Germany
- Center for Biotechnology (CeBiTec), Bielefeld University, Bielefeld, Germany
- *Correspondence: Oliver Hertel,
| | - Anne Neuss
- Biochemical Engineering (AVT.BioVT), RWTH Aachen University, Aachen, Germany
| | - Tobias Busche
- Center for Biotechnology (CeBiTec), Bielefeld University, Bielefeld, Germany
| | - David Brandt
- Center for Biotechnology (CeBiTec), Bielefeld University, Bielefeld, Germany
| | - Jörn Kalinowski
- Center for Biotechnology (CeBiTec), Bielefeld University, Bielefeld, Germany
| | | | - Thomas Noll
- Cell Culture Technology, Faculty of Technology, Bielefeld University, Bielefeld, Germany
- Center for Biotechnology (CeBiTec), Bielefeld University, Bielefeld, Germany
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Min H, Kim SM, Kim D, Lee S, Lee S, Lee JS. Hybrid cell line development system utilizing site-specific integration and methotrexate-mediated gene amplification in Chinese hamster ovary cells. Front Bioeng Biotechnol 2022; 10:977193. [PMID: 36185448 PMCID: PMC9521551 DOI: 10.3389/fbioe.2022.977193] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 08/24/2022] [Indexed: 11/13/2022] Open
Abstract
Site-specific integration has emerged as a promising strategy for streamlined and predictable Chinese hamster ovary (CHO) cell line development (CLD). However, the low specific productivity of the targeted integrants limits their practical application. In this study, we developed a hybrid CLD platform combining site-specific integration of a transgene and dihydrofolate reductase/methotrexate (DHFR/MTX)-mediated gene amplification to generate high-producing recombinant CHO cell lines. We used the CRISPR/Cas9-based recombinase-mediated cassette exchange landing pad platform to integrate the DHFR expression cassette and transgene landing pad into a CHO genomic hot spot, C12orf35 locus, of DHFR-knockout CHO-K1 host cell lines. When subjected to various MTX concentrations up to 1 μM, EGFP-expressing targeted integrants showed a 3.6-fold increase in EGFP expression in the presence of 200 nM MTX, accompanied by an increase in the DHFR and EGFP copy number. A single-step 200 nM MTX amplification increased the specific monoclonal antibody (mAb) productivity (qmAb) of recombinant mAb-producing targeted integrants by 2.8-folds, reaching a qmAb of 9.1–11.0 pg/cell/day. Fluorescence in situ hybridization analysis showed colocalization of DHFR and mAb sequences at the intended chromosomal locations without clear amplified arrays of signals. Most MTX-amplified targeted integrants sustained recombinant mAb production during long-term culture in the absence of MTX, supporting stable gene expression in the amplified cell lines. Our study provides a new CLD platform that increases the productivity of targeted integrants by amplifying the transgene copies.
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Affiliation(s)
- Honggi Min
- Department of Molecular Science and Technology, Ajou University, Suwon, South Korea
| | - Seul Mi Kim
- Department of Molecular Science and Technology, Ajou University, Suwon, South Korea
| | - Dongwoo Kim
- Department of Molecular Science and Technology, Ajou University, Suwon, South Korea
| | - Solhwi Lee
- Department of Applied Chemistry and Biological Engineering, Ajou University, Suwon, South Korea
| | - Sumin Lee
- Department of Molecular Science and Technology, Ajou University, Suwon, South Korea
| | - Jae Seong Lee
- Department of Molecular Science and Technology, Ajou University, Suwon, South Korea
- Department of Applied Chemistry and Biological Engineering, Ajou University, Suwon, South Korea
- *Correspondence: Jae Seong Lee,
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44
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DiAndreth B, Wauford N, Hu E, Palacios S, Weiss R. PERSIST platform provides programmable RNA regulation using CRISPR endoRNases. Nat Commun 2022; 13:2582. [PMID: 35562172 PMCID: PMC9095627 DOI: 10.1038/s41467-022-30172-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Accepted: 04/20/2022] [Indexed: 12/26/2022] Open
Abstract
Regulated transgene expression is an integral component of gene therapies, cell therapies and biomanufacturing. However, transcription factor-based regulation, upon which most applications are based, suffers from complications such as epigenetic silencing that limit expression longevity and reliability. Constitutive transgene transcription paired with post-transcriptional gene regulation could combat silencing, but few such RNA- or protein-level platforms exist. Here we develop an RNA-regulation platform we call "PERSIST" which consists of nine CRISPR-specific endoRNases as RNA-level activators and repressors as well as modular OFF- and ON-switch regulatory motifs. We show that PERSIST-regulated transgenes exhibit strong OFF and ON responses, resist silencing for at least two months, and can be readily layered to construct cascades, logic functions, switches and other sophisticated circuit topologies. The orthogonal, modular and composable nature of this platform as well as the ease in constructing robust and predictable gene circuits promises myriad applications in gene and cell therapies.
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Affiliation(s)
- Breanna DiAndreth
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Noreen Wauford
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Eileen Hu
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Sebastian Palacios
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Ron Weiss
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
- Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
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45
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Schloßhauer JL, Cavak N, Zemella A, Thoring L, Kubick S. Cell Engineering and Cultivation of Chinese Hamster Ovary Cells for the Development of Orthogonal Eukaryotic Cell-free Translation Systems. Front Mol Biosci 2022; 9:832379. [PMID: 35586195 PMCID: PMC9109823 DOI: 10.3389/fmolb.2022.832379] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Accepted: 03/15/2022] [Indexed: 12/03/2022] Open
Abstract
The investigation of protein structures, functions and interactions often requires modifications to adapt protein properties to the specific application. Among many possible methods to equip proteins with new chemical groups, the utilization of orthogonal aminoacyl-tRNA synthetase/tRNA pairs enables the site-specific incorporation of non-canonical amino acids at defined positions in the protein. The open nature of cell-free protein synthesis reactions provides an optimal environment, as the orthogonal components do not need to be transported across the cell membrane and the impact on cell viability is negligible. In the present work, it was shown that the expression of orthogonal aminoacyl-tRNA synthetases in CHO cells prior to cell disruption enhanced the modification of the pharmaceutically relevant adenosine A2a receptor. For this purpose, in complement to transient transfection of CHO cells, an approach based on CRISPR/Cas9 technology was selected to generate a translationally active cell lysate harboring endogenous orthogonal aminoacyl-tRNA synthetase.
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Affiliation(s)
- Jeffrey L. Schloßhauer
- Branch Bioanalytics and Bioprocesses (IZI-BB), Fraunhofer Institute for Cell Therapy and Immunology (IZI), Potsdam, Germany
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany
| | - Niño Cavak
- Branch Bioanalytics and Bioprocesses (IZI-BB), Fraunhofer Institute for Cell Therapy and Immunology (IZI), Potsdam, Germany
| | - Anne Zemella
- Branch Bioanalytics and Bioprocesses (IZI-BB), Fraunhofer Institute for Cell Therapy and Immunology (IZI), Potsdam, Germany
| | - Lena Thoring
- Branch Bioanalytics and Bioprocesses (IZI-BB), Fraunhofer Institute for Cell Therapy and Immunology (IZI), Potsdam, Germany
| | - Stefan Kubick
- Branch Bioanalytics and Bioprocesses (IZI-BB), Fraunhofer Institute for Cell Therapy and Immunology (IZI), Potsdam, Germany
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany
- Faculty of Health Sciences, Joint Faculty of the Brandenburg University of Technology Cottbus –Senftenberg, The Brandenburg Medical School Theodor Fontane and the University of Potsdam, Potsdam, Germany
- *Correspondence: Stefan Kubick,
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46
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Oliviero C, Hinz SC, Bogen JP, Kornmann H, Hock B, Kolmar H, Hagens G. Generation of a Host Cell line containing a MAR-rich landing pad for site-specific integration and expression of transgenes. Biotechnol Prog 2022; 38:e3254. [PMID: 35396920 PMCID: PMC9539524 DOI: 10.1002/btpr.3254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 03/22/2022] [Accepted: 03/31/2022] [Indexed: 11/10/2022]
Abstract
In recent years, targeted gene integration (TI) has been introduced as a strategy for the generation of recombinant mammalian cell lines for the production of biotherapeutics. Besides reducing the immense heterogeneity within a pool of recombinant transfectants, TI also aims at shortening the duration of the current cell line development process. Here we describe the generation of a host cell line carrying Matrix‐Attachment Region (MAR)‐rich landing pads (LPs), which allow for the simultaneous and site‐specific integration of multiple genes of interest (GOIs). We show that several copies of each chicken lysozyme 5'MAR‐based LP containing either BxB1 wild type or mutated recombination sites, integrated at one random chromosomal locus of the host cell genome. We further demonstrate that these LP‐containing host cell lines can be used for the site‐specific integration of several GOIs and thus, generation of transgene‐expressing stable recombinant clones. Transgene expression was shown by site‐specific integration of heavy and light chain genes coding for a monospecific antibody (msAb) as well as for a bi‐specific antibody (bsAb). The genetic stability of the herein described LP‐based recombinant clones expressing msAb or bsAb was demonstrated by cultivating the recombinant clones and measuring antibody titers over 85 generations. We conclude that the host cell containing multiple copies of MAR‐rich landing pads can be successfully used for stable expression of one or several GOIs.
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Affiliation(s)
- Claudia Oliviero
- Institute of Life Technology, Haute Ecole d'Ingénierie HES-SO Valais Wallis, Rue de l'Industrie 19, CH-1950 Sion, Switzerland
| | - Steffen C Hinz
- Institute of Life Technology, Haute Ecole d'Ingénierie HES-SO Valais Wallis, Rue de l'Industrie 19, CH-1950 Sion, Switzerland
| | - Jan P Bogen
- Institute for Organic Chemistry and Biochemistry, Technical University of Darmstadt, Alarich-Weiss-Strasse 4, D-64287, Darmstadt, Germany
| | - Henri Kornmann
- Ferring Biologics Innovation Center, Route de la Corniche 8, CH-1066, Epalinges, Switzerland
| | - Björn Hock
- Ferring Biologics Innovation Center, Route de la Corniche 8, CH-1066, Epalinges, Switzerland.,SwissThera SA, Route de la Corniche 4, CH-1066, Epalinges, Switzerland
| | - Harald Kolmar
- Institute for Organic Chemistry and Biochemistry, Technical University of Darmstadt, Alarich-Weiss-Strasse 4, D-64287, Darmstadt, Germany
| | - Gerrit Hagens
- Institute of Life Technology, Haute Ecole d'Ingénierie HES-SO Valais Wallis, Rue de l'Industrie 19, CH-1950 Sion, Switzerland
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Spahn PN, Zhang X, Hu Q, Lu H, Hamaker NK, Hefzi H, Li S, Kuo CC, Huang Y, Lee JC, Davis AJ, Ly P, Lee KH, Lewis NE. Restoration of DNA repair mitigates genome instability and increases productivity of Chinese hamster ovary cells. Biotechnol Bioeng 2022; 119:963-982. [PMID: 34953085 PMCID: PMC8821244 DOI: 10.1002/bit.28016] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Accepted: 12/18/2021] [Indexed: 11/11/2022]
Abstract
Chinese hamster ovary (CHO) cells are the primary host for manufacturing of therapeutic proteins. However, productivity loss is a major problem and is associated with genome instability, as chromosomal aberrations reduce transgene copy number and decrease protein expression. We analyzed whole-genome sequencing data from 11 CHO cell lines and found deleterious single-nucleotide variants in DNA repair genes. Comparison with primary Chinese hamster cells confirmed DNA repair to be compromised in CHO. Correction of key DNA repair genes by single-nucleotide variant reversal or expression of intact complementary DNAs successfully improved DNA repair and mitigated karyotypic instability. Moreover, overexpression of intact copies of LIG4 and XRCC6 in a CHO cell line expressing secreted alkaline phosphatase mitigated transgene copy loss and improved protein titer retention. These results show that correction of DNA repair genes yields improvements in genome stability in CHO, and provide new opportunities for cell line development for sustainable protein expression.
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Affiliation(s)
- Philipp N. Spahn
- Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, The Novo Nordisk Foundation Center for Biosustainability at the University of California, San Diego School of Medicine, San Diego, La Jolla, CA 92093
| | - Xiaolin Zhang
- Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, DE 19711
| | - Qing Hu
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Huiming Lu
- Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Nathaniel K. Hamaker
- Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, DE 19711
| | - Hooman Hefzi
- Department of Bioengineering, University of California, San Diego, La Jolla, CA 92093
| | - Shangzhong Li
- Department of Bioengineering, University of California, San Diego, La Jolla, CA 92093
| | - Chih-Chung Kuo
- Department of Bioengineering, University of California, San Diego, La Jolla, CA 92093
| | - Yingxiang Huang
- Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093
| | - Jamie C. Lee
- Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, Department of Bioengineering, University of California, San Diego, La Jolla, CA 92093
| | - Anthony J. Davis
- Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Peter Ly
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Kelvin H. Lee
- Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, DE 19711, These authors jointly supervised this work: Kelvin H. Lee, , 302-831-0344, Nathan E. Lewis, , 858-997-5844
| | - Nathan E. Lewis
- Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, The Novo Nordisk Foundation Center for Biosustainability at the University of California, San Diego School of Medicine, San Diego, La Jolla, CA 92093, Department of Bioengineering, University of California, San Diego, La Jolla, CA 92093, These authors jointly supervised this work: Kelvin H. Lee, , 302-831-0344, Nathan E. Lewis, , 858-997-5844
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48
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Szkodny AC, Lee KH. Biopharmaceutical Manufacturing: Historical Perspectives and Future Directions. Annu Rev Chem Biomol Eng 2022; 13:141-165. [PMID: 35300518 DOI: 10.1146/annurev-chembioeng-092220-125832] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
This review describes key milestones related to the production of biopharmaceuticals-therapies manufactured using recombinant DNA technology. The market for biopharmaceuticals has grown significantly since the first biopharmaceutical approval in 1982, and the scientific maturity of the technologies used in their manufacturing processes has grown concomitantly. Early processes relied on established unit operations, with research focused on process scale-up and improved culture productivity. In the early 2000s, changes in regulatory frameworks and the introduction of Quality by Design emphasized the importance of developing manufacturing processes to deliver a desired product quality profile. As a result, companies adopted platform processes and focused on understanding the dynamic interplay between product quality and processing conditions. The consistent and reproducible manufacturing processes of today's biopharmaceutical industry have set high standards for product efficacy, quality, and safety, and as the industry continues to evolve in the coming decade, intensified processing capabilities for an expanded range of therapeutic modalities will likely become routine. Expected final online publication date for the Annual Review of Chemical and Biomolecular Engineering, Volume 13 is October 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Alana C Szkodny
- Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware 19716, USA; ;
| | - Kelvin H Lee
- Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware 19716, USA; ;
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49
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Aznauryan E, Yermanos A, Kinzina E, Devaux A, Kapetanovic E, Milanova D, Church GM, Reddy ST. Discovery and validation of human genomic safe harbor sites for gene and cell therapies. CELL REPORTS METHODS 2022; 2:100154. [PMID: 35474867 PMCID: PMC9017210 DOI: 10.1016/j.crmeth.2021.100154] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 11/12/2021] [Accepted: 12/22/2021] [Indexed: 12/13/2022]
Abstract
Existing approaches to therapeutic gene transfer are marred by the transient nature of gene expression following non-integrative gene delivery and by safety concerns due to the random mechanism of viral-mediated genomic insertions. The disadvantages of these methods encourage future research in identifying human genomic sites that allow for durable and safe expression of genes of interest. We conducted a bioinformatic search followed by the experimental characterization of human genomic sites, identifying two that demonstrated the stable expression of integrated reporter and therapeutic genes without malignant changes to the cellular transcriptome. The cell-type agnostic criteria used in our bioinformatic search suggest widescale applicability of identified sites for engineering of a diverse range of tissues for clinical and research purposes, including modified T cells for cancer therapy and engineered skin to ameliorate inherited diseases and aging. In addition, the stable and robust levels of gene expression from identified sites allow for the industry-scale biomanufacturing of proteins in human cells.
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Affiliation(s)
- Erik Aznauryan
- Department of Biosystems Science and Engineering, ETH Zürich, Basel, Switzerland
- Systems Biology Program, Life Science Zürich Graduate School, Zürich, Switzerland
- Wyss Institute for Biologically Inspired Engineering at Harvard University, Boston, MA 02115, USA
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Alexander Yermanos
- Department of Biosystems Science and Engineering, ETH Zürich, Basel, Switzerland
- Institute of Microbiology, ETH Zürich, Zürich, Switzerland
- Department of Pathology and Immunology, University of Geneva, Geneva, Switzerland
| | - Elvira Kinzina
- McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Anna Devaux
- Department of Biomedicine, University of Basel, Basel, Switzerland
| | - Edo Kapetanovic
- Department of Biosystems Science and Engineering, ETH Zürich, Basel, Switzerland
| | - Denitsa Milanova
- Wyss Institute for Biologically Inspired Engineering at Harvard University, Boston, MA 02115, USA
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - George M. Church
- Wyss Institute for Biologically Inspired Engineering at Harvard University, Boston, MA 02115, USA
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Sai T. Reddy
- Department of Biosystems Science and Engineering, ETH Zürich, Basel, Switzerland
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50
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Massively parallel phenotyping of coding variants in cancer with Perturb-seq. Nat Biotechnol 2022; 40:896-905. [DOI: 10.1038/s41587-021-01160-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2020] [Accepted: 11/11/2021] [Indexed: 02/08/2023]
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