101
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Zalai D, Hevér H, Lovász K, Molnár D, Wechselberger P, Hofer A, Párta L, Putics Á, Herwig C. A control strategy to investigate the relationship between specific productivity and high-mannose glycoforms in CHO cells. Appl Microbiol Biotechnol 2016; 100:7011-24. [PMID: 26910040 PMCID: PMC4947490 DOI: 10.1007/s00253-016-7380-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Revised: 02/01/2016] [Accepted: 02/03/2016] [Indexed: 12/26/2022]
Abstract
The integration of physiological knowledge into process control strategies is a cornerstone for the improvement of biopharmaceutical cell culture technologies. The present contribution investigates the applicability of specific productivity as a physiological control parameter in a cell culture process producing a monoclonal antibody (mAb) in CHO cells. In order to characterize cell physiology, the on-line oxygen uptake rate (OUR) was monitored and the time-resolved specific productivity was calculated as physiological parameters. This characterization enabled to identify the tight link between the deprivation of tyrosine and the decrease in cell respiration and in specific productivity. Subsequently, this link was used to control specific productivity by applying different feeding profiles. The maintenance of specific productivity at various levels enabled to identify a correlation between the rate of product formation and the relative abundance of high-mannose glycoforms. An increase in high mannose content was assumed to be the result of high specific productivity. Furthermore, the high mannose content as a function of cultivation pH and specific productivity was investigated in a design of experiment approach. This study demonstrated how physiological parameters could be used to understand interactions between process parameters, physiological parameters, and product quality attributes.
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Affiliation(s)
- Dénes Zalai
- Department of Biotechnology, Gedeon Richter Plc., 19-21, Gyömrői út, Budapest, 1103, Hungary.,Institute of Chemical Engineering, Research Area Biochemical Engineering, Vienna University of Technology, Gumpendorfer Strasse 1a, 1060, Vienna, Austria
| | - Helga Hevér
- Spectroscopic Research Department, Gedeon Richter Plc., 19-21, Gyömrői út, Budapest, 1103, Hungary
| | - Krisztina Lovász
- Department of Biotechnology, Gedeon Richter Plc., 19-21, Gyömrői út, Budapest, 1103, Hungary
| | - Dóra Molnár
- Department of Biotechnology, Gedeon Richter Plc., 19-21, Gyömrői út, Budapest, 1103, Hungary
| | - Patrick Wechselberger
- Institute of Chemical Engineering, Research Area Biochemical Engineering, Vienna University of Technology, Gumpendorfer Strasse 1a, 1060, Vienna, Austria.,CD Laboratory for Mechanistic and Physiological Methods for Improved Bioprocesses, Vienna, Austria
| | - Alexandra Hofer
- Institute of Chemical Engineering, Research Area Biochemical Engineering, Vienna University of Technology, Gumpendorfer Strasse 1a, 1060, Vienna, Austria
| | - László Párta
- Department of Biotechnology, Gedeon Richter Plc., 19-21, Gyömrői út, Budapest, 1103, Hungary
| | - Ákos Putics
- Department of Biotechnology, Gedeon Richter Plc., 19-21, Gyömrői út, Budapest, 1103, Hungary
| | - Christoph Herwig
- Institute of Chemical Engineering, Research Area Biochemical Engineering, Vienna University of Technology, Gumpendorfer Strasse 1a, 1060, Vienna, Austria. .,CD Laboratory for Mechanistic and Physiological Methods for Improved Bioprocesses, Vienna, Austria.
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102
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Tastanova A, Schulz A, Folcher M, Tolstrup A, Puklowski A, Kaufmann H, Fussenegger M. Overexpression of YY1 increases the protein production in mammalian cells. J Biotechnol 2016; 219:72-85. [DOI: 10.1016/j.jbiotec.2015.12.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Revised: 12/02/2015] [Accepted: 12/09/2015] [Indexed: 01/07/2023]
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103
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Badsha MB, Kurata H, Onitsuka M, Oga T, Omasa T. Metabolic analysis of antibody producing Chinese hamster ovary cell culture under different stresses conditions. J Biosci Bioeng 2016; 122:117-24. [PMID: 26803706 DOI: 10.1016/j.jbiosc.2015.12.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Revised: 12/15/2015] [Accepted: 12/17/2015] [Indexed: 01/03/2023]
Abstract
Chinese hamster ovary (CHO) cells are commonly used as the host cell lines concerning their ability to produce therapeutic proteins with complex post-translational modifications. In this study, we have investigated the time course extra- and intracellular metabolome data of the CHO-K1 cell line, under a control and stress conditions. The addition of NaCl and trehalose greatly suppressed cell growth, where the maximum viable cell density of NaCl and trehalose cultures were 2.2-fold and 2.8-fold less than that of a control culture. Contrariwise, the antibody production of both the NaCl and trehalose cultures was sustained for a longer time to surpass that of the control culture. The NaCl and trehalose cultures showed relatively similar dynamics of cell growth, antibody production, and substrate/product concentrations, while they indicated different dynamics from the control culture. The principal component analysis of extra- and intracellular metabolome dynamics indicated that their dynamic behaviors were consistent with biological functions. The qualitative pattern matching classification and hierarchical clustering analyses for the intracellular metabolome identified the metabolite clusters whose dynamic behaviors depend on NaCl and trehalose. The volcano plot revealed several reporter metabolites whose dynamics greatly change between in the NaCl and trehalose cultures. The elastic net identified some critical, intracellular metabolites that are distinct between the NaCl and trehalose. While a relatively small number of intracellular metabolites related to the cell growth, glucose, glutamine, lactate and ammonium ion concentrations, the mechanism of antibody production was suggested to be very complicated or not to be explained by elastic net regression analysis.
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Affiliation(s)
- Md Bahadur Badsha
- Department of Bioscience and Bioinformatics, Kyushu Institute of Technology, 680-4 Kawazu, Iizuka, Fukuoka 820-8502, Japan.
| | - Hiroyuki Kurata
- Department of Bioscience and Bioinformatics, Kyushu Institute of Technology, 680-4 Kawazu, Iizuka, Fukuoka 820-8502, Japan; Biomedical Informatics R&D Center, Kyushu Institute of Technology, 680-4 Kawazu, Iizuka, Fukuoka 820-8502, Japan.
| | - Masayoshi Onitsuka
- Institute of Technology and Science, Tokushima University, 2-1 Minamijosanjima-cho, Tokushima 770-8506, Japan.
| | - Takushi Oga
- Human Metabolome Technologies, Inc., 24 Denby Road, Suite 217, Boston, MA 02134, USA.
| | - Takeshi Omasa
- Department of Biotechnology, Graduate School of Engineering, Osaka University, U1E801, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
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104
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Brown AJ, James DC. Precision control of recombinant gene transcription for CHO cell synthetic biology. Biotechnol Adv 2015; 34:492-503. [PMID: 26721629 DOI: 10.1016/j.biotechadv.2015.12.012] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Revised: 12/11/2015] [Accepted: 12/22/2015] [Indexed: 11/30/2022]
Abstract
The next generation of mammalian cell factories for biopharmaceutical production will be genetically engineered to possess both generic and product-specific manufacturing capabilities that may not exist naturally. Introduction of entirely new combinations of synthetic functions (e.g. novel metabolic or stress-response pathways), and retro-engineering of existing functional cell modules will drive disruptive change in cellular manufacturing performance. However, before we can apply the core concepts underpinning synthetic biology (design, build, test) to CHO cell engineering we must first develop practical and robust enabling technologies. Fundamentally, we will require the ability to precisely control the relative stoichiometry of numerous functional components we simultaneously introduce into the host cell factory. In this review we discuss how this can be achieved by design of engineered promoters that enable concerted control of recombinant gene transcription. We describe the specific mechanisms of transcriptional regulation that affect promoter function during bioproduction processes, and detail the highly-specific promoter design criteria that are required in the context of CHO cell engineering. The relative applicability of diverse promoter development strategies are discussed, including re-engineering of natural sequences, design of synthetic transcription factor-based systems, and construction of synthetic promoters. This review highlights the potential of promoter engineering to achieve precision transcriptional control for CHO cell synthetic biology.
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Affiliation(s)
- Adam J Brown
- Department of Chemical and Biological Engineering, University of Sheffield, Sheffield S1 3JD, England, United Kingdom
| | - David C James
- Department of Chemical and Biological Engineering, University of Sheffield, Sheffield S1 3JD, England, United Kingdom.
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105
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Abbott WM, Middleton B, Kartberg F, Claesson J, Roth R, Fisher D. Optimisation of a simple method to transiently transfect a CHO cell line in high-throughput and at large scale. Protein Expr Purif 2015; 116:113-9. [DOI: 10.1016/j.pep.2015.08.016] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Revised: 08/13/2015] [Accepted: 08/14/2015] [Indexed: 12/12/2022]
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106
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The art of CHO cell engineering: A comprehensive retrospect and future perspectives. Biotechnol Adv 2015; 33:1878-96. [DOI: 10.1016/j.biotechadv.2015.10.015] [Citation(s) in RCA: 174] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Revised: 10/21/2015] [Accepted: 10/30/2015] [Indexed: 12/14/2022]
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107
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Johari YB, Estes SD, Alves CS, Sinacore MS, James DC. Integrated cell and process engineering for improved transient production of a “difficult-to-express“ fusion protein by CHO cells. Biotechnol Bioeng 2015; 112:2527-42. [DOI: 10.1002/bit.25687] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Revised: 06/08/2015] [Accepted: 06/24/2015] [Indexed: 12/11/2022]
Affiliation(s)
- Yusuf B. Johari
- Department of Chemical and Biological Engineering; University of Sheffield; ChELSI Institute; Mappin Street; Sheffield S1 3JD UK
| | - Scott D. Estes
- Cell Culture Development; Biogen Idec, Inc.; Cambridge Massachusetts
| | | | - Marty S. Sinacore
- Cell Culture Development; Biogen Idec, Inc.; Cambridge Massachusetts
| | - David C. James
- Department of Chemical and Biological Engineering; University of Sheffield; ChELSI Institute; Mappin Street; Sheffield S1 3JD UK
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108
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Tang H, Bao X, Shen Y, Song M, Wang S, Wang C, Hou J. Engineering protein folding and translocation improves heterologous protein secretion inSaccharomyces cerevisiae. Biotechnol Bioeng 2015; 112:1872-82. [DOI: 10.1002/bit.25596] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Revised: 03/11/2015] [Accepted: 03/16/2015] [Indexed: 11/10/2022]
Affiliation(s)
- Hongting Tang
- State Key Laboratory of Microbial Technology; Shandong University; Jinan 250100 China
| | - Xiaoming Bao
- State Key Laboratory of Microbial Technology; Shandong University; Jinan 250100 China
| | - Yu Shen
- State Key Laboratory of Microbial Technology; Shandong University; Jinan 250100 China
| | - Meihui Song
- State Key Laboratory of Microbial Technology; Shandong University; Jinan 250100 China
| | - Shenghuan Wang
- State Key Laboratory of Microbial Technology; Shandong University; Jinan 250100 China
| | - Chengqiang Wang
- State Key Laboratory of Microbial Technology; Shandong University; Jinan 250100 China
| | - Jin Hou
- State Key Laboratory of Microbial Technology; Shandong University; Jinan 250100 China
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109
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Alves CS, Gilbert A, Dalvi S, Germain BS, Xie W, Estes S, Kshirsagar R, Ryll T. Integration of cell line and process development to overcome the challenge of a difficult to express protein. Biotechnol Prog 2015; 31:1201-11. [DOI: 10.1002/btpr.2091] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Revised: 04/22/2015] [Indexed: 12/13/2022]
Affiliation(s)
| | - Alan Gilbert
- Biogen, Cell Culture Development; 125 Binney St Cambridge MA 02142
| | - Swati Dalvi
- Biogen, Cell Culture Development; 125 Binney St Cambridge MA 02142
| | | | - Wenqi Xie
- Biogen, Cell Culture Development; 125 Binney St Cambridge MA 02142
| | - Scott Estes
- Biogen, Cell Culture Development; 125 Binney St Cambridge MA 02142
| | | | - Thomas Ryll
- Biogen, Cell Culture Development; 125 Binney St Cambridge MA 02142
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110
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A PiggyBac-mediated approach for muscle gene transfer or cell therapy. Stem Cell Res 2014; 13:390-403. [PMID: 25310255 DOI: 10.1016/j.scr.2014.08.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2014] [Revised: 08/27/2014] [Accepted: 08/29/2014] [Indexed: 11/22/2022] Open
Abstract
An emerging therapeutic approach for Duchenne muscular dystrophy is the transplantation of autologous myogenic progenitor cells genetically modified to express dystrophin. The use of this approach is challenged by the difficulty in maintaining these cells ex vivo while keeping their myogenic potential, and ensuring sufficient transgene expression following their transplantation and myogenic differentiation in vivo. We investigated the use of the piggyBac transposon system to achieve stable gene expression when transferred to cultured mesoangioblasts and into murine muscles. Without selection, up to 8% of the mesoangioblasts expressed the transgene from 1 to 2 genomic copies of the piggyBac vector. Integration occurred mostly in intergenic genomic DNA and transgene expression was stable in vitro. Intramuscular transplantation of mouse Tibialis anterior muscles with mesoangioblasts containing the transposon led to sustained myofiber GFP expression in vivo. In contrast, the direct electroporation of the transposon-donor plasmids in the mouse Tibialis muscles in vivo did not lead to sustained transgene expression despite molecular evidence of piggyBac transposition in vivo. Together these findings provide a proof-of-principle that piggyBac transposon may be considered for mesoangioblast cell-based therapies of muscular dystrophies.
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111
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Engineering cells to improve protein expression. Curr Opin Struct Biol 2014; 26:32-8. [PMID: 24704806 DOI: 10.1016/j.sbi.2014.03.005] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Revised: 02/24/2014] [Accepted: 03/10/2014] [Indexed: 12/22/2022]
Abstract
Cellular engineering of bacteria, fungi, insect cells and mammalian cells is a promising methodology to improve recombinant protein production for structural, biochemical, and commercial applications. Increased understanding of the host organism biology has suggested engineering strategies targeting bottlenecks in transcription, translation, protein processing and secretory pathways, as well as cell growth and survival. A combination of metabolic engineering and synthetic biology has been used to improve the properties of cells for protein production, which has resulted in enhanced yields of multiple protein classes.
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112
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Nishimiya D. Proteins improving recombinant antibody production in mammalian cells. Appl Microbiol Biotechnol 2013; 98:1031-42. [PMID: 24327213 DOI: 10.1007/s00253-013-5427-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2013] [Revised: 11/20/2013] [Accepted: 11/21/2013] [Indexed: 12/13/2022]
Abstract
Mammalian cells have been successfully used for the industrial manufacture of antibodies due to their ability to synthesize antibodies correctly. Nascent polypeptides must be subjected to protein folding and assembly in the ER and the Golgi to be secreted as mature proteins. If these reactions do not proceed appropriately, unfolded or misfolded proteins are degraded by the ER-associated degradation (ERAD) pathway. The accumulation of unfolded proteins or intracellular antibody crystals accompanied by this failure triggers the unfolded protein response (UPR), which can considerably attenuate the levels of translation, folding, assembly, and secretion, resulting in reduction of antibody productivity. Accumulating studies by omics-based analysis of recombinant mammalian cells suggest that not only protein secretion processes including protein folding and assembly but also translation are likely to be the rate-limiting factors for increasing antibody production. Here, this review describes the mechanism of antibody folding and assembly and recent advantages which could improve recombinant antibody production in mammalian cells by utilizing proteins such as ER chaperones or UPR-related proteins.
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Affiliation(s)
- Daisuke Nishimiya
- New Modality Research Laboratories, R&D Division, Daiichi Sankyo Co., Ltd., 1-2-58 Hiromachi, Shinagawa-ku, Tokyo, 140-8710, Japan,
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113
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Bire S, Ley D, Casteret S, Mermod N, Bigot Y, Rouleux-Bonnin F. Optimization of the piggyBac transposon using mRNA and insulators: toward a more reliable gene delivery system. PLoS One 2013; 8:e82559. [PMID: 24312663 PMCID: PMC3849487 DOI: 10.1371/journal.pone.0082559] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2013] [Accepted: 10/23/2013] [Indexed: 12/23/2022] Open
Abstract
Integrating and expressing stably a transgene into the cellular genome remain major challenges for gene-based therapies and for bioproduction purposes. While transposon vectors mediate efficient transgene integration, expression may be limited by epigenetic silencing, and persistent transposase expression may mediate multiple transposition cycles. Here, we evaluated the delivery of the piggyBac transposase messenger RNA combined with genetically insulated transposons to isolate the transgene from neighboring regulatory elements and stabilize expression. A comparison of piggyBac transposase expression from messenger RNA and DNA vectors was carried out in terms of expression levels, transposition efficiency, transgene expression and genotoxic effects, in order to calibrate and secure the transposition-based delivery system. Messenger RNA reduced the persistence of the transposase to a narrow window, thus decreasing side effects such as superfluous genomic DNA cleavage. Both the CTF/NF1 and the D4Z4 insulators were found to mediate more efficient expression from a few transposition events. We conclude that the use of engineered piggyBac transposase mRNA and insulated transposons offer promising ways of improving the quality of the integration process and sustaining the expression of transposon vectors.
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Affiliation(s)
- Solenne Bire
- GICC, UMR CNRS 7292, Université François Rabelais, Tours, France
- Institute of Biotechnology, University of Lausanne, and Center for Biotechnology UNIL-EPFL, Lausanne, Switzerland
- PRC, UMR INRA-CNRS 7247, Centre INRA Val de Loire, Nouzilly, France
| | - Déborah Ley
- Institute of Biotechnology, University of Lausanne, and Center for Biotechnology UNIL-EPFL, Lausanne, Switzerland
| | - Sophie Casteret
- PRC, UMR INRA-CNRS 7247, Centre INRA Val de Loire, Nouzilly, France
| | - Nicolas Mermod
- Institute of Biotechnology, University of Lausanne, and Center for Biotechnology UNIL-EPFL, Lausanne, Switzerland
| | - Yves Bigot
- PRC, UMR INRA-CNRS 7247, Centre INRA Val de Loire, Nouzilly, France
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114
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Haredy AM, Nishizawa A, Honda K, Ohya T, Ohtake H, Omasa T. Improved antibody production in Chinese hamster ovary cells by ATF4 overexpression. Cytotechnology 2013; 65:993-1002. [PMID: 24026344 DOI: 10.1007/s10616-013-9631-x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2013] [Accepted: 08/10/2013] [Indexed: 12/11/2022] Open
Abstract
To improve antibody production in Chinese hamster ovary (CHO) cells, the humanized antibody-producing CHO DP-12-SF cell line was transfected with the gene encoding activating transcription factor 4 (ATF4), a central factor in the unfolded protein response. Overexpression of ATF4 significantly enhanced the production of antibody in the CHO DP-12-SF cell line. The specific IgG production rate of in the ATF4-overexpressing CHO-ATF4-16 cells was approximately 2.4 times that of the parental host cell line. Clone CHO-ATF4-16 did not show any change in growth rate compared with the parental cells or mock-transfected CHO-DP12-SF cells. The expression levels of mRNAs encoding both the antibody heavy and light chains in the CHO-ATF4-16 clone were analyzed. This analysis showed that ATF4 overexpression improved the total production and specific production rate of antibody without affecting the mRNA transcription level. These results indicate that ATF4 overexpression is a promising method for improving recombinant IgG production in CHO cells.
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Affiliation(s)
- Ahmad M Haredy
- Department of Biotechnology, Graduate School of Engineering, Osaka University, Suita, Osaka, 565-0871, Japan
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115
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MAR elements and transposons for improved transgene integration and expression. PLoS One 2013; 8:e62784. [PMID: 23646143 PMCID: PMC3640020 DOI: 10.1371/journal.pone.0062784] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2013] [Accepted: 03/24/2013] [Indexed: 01/01/2023] Open
Abstract
Reliable and long-term expression of transgenes remain significant challenges for gene therapy and biotechnology applications, especially when antibiotic selection procedures are not applicable. In this context, transposons represent attractive gene transfer vectors because of their ability to promote efficient genomic integration in a variety of mammalian cell types. However, expression from genome-integrating vectors may be inhibited by variable gene transcription and/or silencing events. In this study, we assessed whether inclusion of two epigenetic control elements, the human Matrix Attachment Region (MAR) 1–68 and X-29, in a piggyBac transposon vector, may lead to more reliable and efficient expression in CHO cells. We found that addition of the MAR 1–68 at the center of the transposon did not interfere with transposition frequency, and transgene expressing cells could be readily detected from the total cell population without antibiotic selection. Inclusion of the MAR led to higher transgene expression per integrated copy, and reliable expression could be obtained from as few as 2–4 genomic copies of the MAR-containing transposon vector. The MAR X-29-containing transposons was found to mediate elevated expression of therapeutic proteins in polyclonal or monoclonal CHO cell populations using a transposable vector devoid of selection gene. Overall, we conclude that MAR and transposable vectors can be used to improve transgene expression from few genomic transposition events, which may be useful when expression from a low number of integrated transgene copies must be obtained and/or when antibiotic selection cannot be applied.
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