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Zhang K, Barbieri E, LeBarre J, Rameez S, Mostafa S, Menegatti S. Peptonics: A new family of cell-protecting surfactants for the recombinant expression of therapeutic proteins in mammalian cell cultures. Biotechnol J 2024; 19:e2300261. [PMID: 37844203 DOI: 10.1002/biot.202300261] [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: 06/02/2023] [Revised: 08/08/2023] [Accepted: 10/05/2023] [Indexed: 10/18/2023]
Abstract
Polymer surfactants are key components of cell culture media as they prevent mechanical damage during fermentation in stirred bioreactors. Among cell-protecting surfactants, Pluronics are widely utilized in biomanufacturing to ensure high cell viability and productivity. Monodispersity of monomer sequence and length is critical for the effectiveness of Pluronics-since minor deviations can damage the cells-but is challenging to achieve due to the stochastic nature of polymerization. Responding to this challenge, this study introduces Peptonics, a novel family of peptide and peptoid surfactants whose monomer composition and sequence are designed to achieve high cell viability and productivity at a fraction of chain length and cost of Pluronics. A designed ensemble of Peptonics was initially characterized via light scattering and tensiometry to select sequences whose phase behavior and tensioactivity align with those of Pluronics. Selected sequences were evaluated as cell-protecting surfactants using Chinese hamster ovary (CHO) cells expressing therapeutic monoclonal antibodies (mAb). Peptonics IH-T1010, ih-T1010, and ih-T1020 afforded high cell density (up to 3 × 107 cells mL-1 ) and viability (up to 95% within 10 days of culture), while reducing the accumulation of ammonia (a toxic metabolite) by ≈10% compared to Pluronic F-68. Improved cell viability afforded high mAb titer (up to 5.5 mg mL-1 ) and extended the production window beyond 14 days; notably, Peptonic IH-T1020 decreased mAb fragmentation and aggregation ≈5%, and lowered the titer of host cell proteins by 16% compared to Pluronic F-68. These features can improve significantly the purification of mAbs, thus increasing their availability at a lower cost to patients.
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Affiliation(s)
- Ka Zhang
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina, USA
- KBI Biopharma, Durham, North Carolina, USA
| | - Eduardo Barbieri
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina, USA
- LigaTrap Technologies LLC, Raleigh, North Carolina, USA
| | - Jacob LeBarre
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina, USA
| | | | | | - Stefano Menegatti
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina, USA
- LigaTrap Technologies LLC, Raleigh, North Carolina, USA
- Biomanufacturing Training and Education Center (BTEC), North Carolina State University, Raleigh, North Carolina, USA
- North Carolina Viral Vector Initiative in Research and Learning (NC-VVIRAL), North Carolina State University, Raleigh, North Carolina, USA
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2
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Rajan SAP, Sherfey J, Ohri S, Nichols L, Smith JT, Parekh P, Kadar EP, Clark F, George BT, Gregory L, Tess D, Gosset JR, Liras J, Geishecker E, Obach RS, Cirit M. A Novel Milli-fluidic Liver Tissue Chip with Continuous Recirculation for Predictive Pharmacokinetics Applications. AAPS J 2023; 25:102. [PMID: 37891356 DOI: 10.1208/s12248-023-00870-x] [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: 07/26/2023] [Accepted: 10/12/2023] [Indexed: 10/29/2023] Open
Abstract
A crucial step in lead selection during drug development is accurate estimation and optimization of hepatic clearance using in vitro methods. However, current methods are limited by factors such as lack of physiological relevance, short culture/incubation times that are not consistent with drug exposure patterns in patients, use of drug absorbing materials, and evaporation during long-term incubation. To address these technological needs, we developed a novel milli-fluidic human liver tissue chip (LTC) that was designed with continuous media recirculation and optimized for hepatic cultures using human primary hepatocytes. Here, we characterized the LTC using a series of physiologically relevant metrics and test compounds to demonstrate that we could accurately predict the PK of both low- and high-clearance compounds. The non-biological characterization indicated that the cyclic olefin copolymer (COC)-based LTC exhibited negligible evaporation and minimal non-specific binding of drugs of varying ionic states and lipophilicity. Biologically, the LTC exhibited functional and polarized hepatic culture with sustained metabolic CYP activity for at least 15 days. This long-term culture was then used for drug clearance studies for low- and high-clearance compounds for at least 12 days, and clearance was estimated for a range of compounds with high in vitro-in vivo correlation (IVIVC). We also demonstrated that LTC can be induced by rifampicin, and the culture age had insignificant effect on depletion kinetic and predicted clearance value. Thus, we used advances in bioengineering to develop a novel purpose-built platform with high reproducibility and minimal variability to address unmet needs for PK applications.
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Affiliation(s)
| | - Jason Sherfey
- Javelin Biotech Inc, 299 Washington street, Woburn, Massachusetts, 01801, USA
| | - Shivam Ohri
- Javelin Biotech Inc, 299 Washington street, Woburn, Massachusetts, 01801, USA
| | - Lauren Nichols
- Javelin Biotech Inc, 299 Washington street, Woburn, Massachusetts, 01801, USA
| | - J Tyler Smith
- Javelin Biotech Inc, 299 Washington street, Woburn, Massachusetts, 01801, USA
| | - Paarth Parekh
- Javelin Biotech Inc, 299 Washington street, Woburn, Massachusetts, 01801, USA
| | - Eugene P Kadar
- Pfizer Global Research and Development, Groton Laboratories, Eastern Point Road, Groton, Connecticut, 06340, USA
| | - Frances Clark
- Pfizer Global Research and Development, Groton Laboratories, Eastern Point Road, Groton, Connecticut, 06340, USA
| | - Billy T George
- Pfizer Global Research and Development, Groton Laboratories, Eastern Point Road, Groton, Connecticut, 06340, USA
| | - Lauren Gregory
- Pfizer Global Research and Development, Groton Laboratories, Eastern Point Road, Groton, Connecticut, 06340, USA
| | - David Tess
- Pfizer Global Research and Development, Groton Laboratories, Eastern Point Road, Groton, Connecticut, 06340, USA
| | - James R Gosset
- Pfizer Worldwide Research and Development, 610 Main Street, Cambridge, Massachusetts, 02139, USA
| | - Jennifer Liras
- Pfizer Worldwide Research and Development, 610 Main Street, Cambridge, Massachusetts, 02139, USA
| | - Emily Geishecker
- Javelin Biotech Inc, 299 Washington street, Woburn, Massachusetts, 01801, USA
| | - R Scott Obach
- Pfizer Global Research and Development, Groton Laboratories, Eastern Point Road, Groton, Connecticut, 06340, USA
| | - Murat Cirit
- Javelin Biotech Inc, 299 Washington street, Woburn, Massachusetts, 01801, USA.
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3
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Legrand C, Cheeks M, Sellick C, Mantle M. MRI hydrodynamic characterization of an ambr15® bioreactor. Biochem Eng J 2022. [DOI: 10.1016/j.bej.2021.108304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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4
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Sharma R, Harrison STL, Tai SL. Advances in Bioreactor Systems for the Production of Biologicals in Mammalian Cells. CHEMBIOENG REVIEWS 2021. [DOI: 10.1002/cben.202100022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Rajesh Sharma
- University of Cape Town Centre for Bioprocess Engineering Research (CeBER) Department of Chemical Engineering Faculty of Engineering and the Built Environment Private Bag 7701 Rondebosch South Africa
| | - Susan T. L. Harrison
- University of Cape Town Centre for Bioprocess Engineering Research (CeBER) Department of Chemical Engineering Faculty of Engineering and the Built Environment Private Bag 7701 Rondebosch South Africa
| | - Siew Leng Tai
- University of Cape Town Centre for Bioprocess Engineering Research (CeBER) Department of Chemical Engineering Faculty of Engineering and the Built Environment Private Bag 7701 Rondebosch South Africa
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Afeyan NB, Cooney CL. Professor Daniel I.C. Wang: A Legacy of Education, Innovation, Publication, and Leadership. Biotechnol Bioeng 2021; 117:3615-3627. [PMID: 33616929 PMCID: PMC7839494 DOI: 10.1002/bit.27644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Affiliation(s)
- Noubar B Afeyan
- Flagship Ventures, One Memorial Drive, 7th Floor, Cambridge, Massachusetts.,Sloan School of Management, Massachusetts Institute of Technology, 50 Memorial Drive, Cambridge, Massachusetts
| | - Charles L Cooney
- Department of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts
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Kok ADX, Mohd Yusoff NF, Sekeli R, Wee CY, Lamasudin DU, Ong-Abdullah J, Lai KS. Pluronic F-68 Improves Callus Proliferation of Recalcitrant Rice Cultivar via Enhanced Carbon and Nitrogen Metabolism and Nutrients Uptake. FRONTIERS IN PLANT SCIENCE 2021; 12:667434. [PMID: 34149763 PMCID: PMC8207202 DOI: 10.3389/fpls.2021.667434] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 04/27/2021] [Indexed: 05/12/2023]
Abstract
Pluronic F-68 (PF-68) is a non-ionic surfactant used in plant tissue culture as a growth additive. Despite its usage as a plant growth enhancer, the mechanism underlying the growth-promoting effects of PF-68 remains largely unknown. Hence, this study was undertaken to elucidate the growth-promoting mechanism of PF-68 using recalcitrant MR 219 callus as a model. Supplementation of 0.04% PF-68 (optimum concentration) was shown to enhance callus proliferation. The treated callus recorded enhanced sugar content, protein content, and glutamate synthase activity as exemplified in the comparative proteome analysis, showing protein abundance involved in carbohydrate metabolism (alpha amylase), protein biosynthesis (ribosomal proteins), and nitrogen metabolism (glutamate synthase), which are crucial to plant growth and development. Moreover, an increase in nutrients uptake was also noted with potassium topping the list, suggesting a vital role of K in governing plant growth. In contrast, 0.10% PF-68 (high concentration) induced stress response in the callus, revealing an increment in phenylalanine ammonia lyase activity, malondialdehyde content, and peroxidase activity, which were consistent with high abundance of phenylalanine ammonia lyase, peroxidase, and peroxiredoxin proteins detected and concomitant with a reduced level of esterase activity. The data highlighted that incorporation of PF-68 at optimum concentration improved callus proliferation of recalcitrant MR 219 through enhanced carbohydrate metabolism, nitrogen metabolism, and nutrient uptake. However, growth-promoting effects of PF-68 are concentration dependent.
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Affiliation(s)
- Andrew De-Xian Kok
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, Malaysia
| | - Nur Fatihah Mohd Yusoff
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, Malaysia
| | - Rogayah Sekeli
- Biotechnology and Nanotechnology Research Centre, Malaysian Agricultural Research and Development Institute (MARDI), Kuala Lumpur, Malaysia
| | - Chien-Yeong Wee
- Biotechnology and Nanotechnology Research Centre, Malaysian Agricultural Research and Development Institute (MARDI), Kuala Lumpur, Malaysia
| | - Dhilia Udie Lamasudin
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, Malaysia
| | - Janna Ong-Abdullah
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, Malaysia
- *Correspondence: Janna Ong-Abdullah
| | - Kok-Song Lai
- Health Sciences Division, Abu Dhabi Women's College, Higher Colleges of Technology, Abu Dhabi, United Arab Emirates
- Kok-Song Lai
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7
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Kok ADX, Wan Abdullah WMAN, Tan NP, Ong-Abdullah J, Sekeli R, Wee CY, Lai KS. Growth promoting effects of Pluronic F-68 on callus proliferation of recalcitrant rice cultivar. 3 Biotech 2020; 10:116. [PMID: 32117677 PMCID: PMC7024072 DOI: 10.1007/s13205-020-2118-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Accepted: 02/04/2020] [Indexed: 12/14/2022] Open
Abstract
This study was undertaken to evaluate growth-promoting effects of Pluronic F-68 (PF-68) on recalcitrant MR 219 rice callus. Our study shows that calli grown on Murashige and Skoog medium supplemented with 0.04% PF-68 significantly increased callus proliferation by 58.80% (fresh weight) and 23.98% (dry weight) while root formation from callus was enhanced by 28.57%. Enhanced callus proliferation was supported by biochemical analysis, whereby highest amount of soluble sugar (1.77 mg/mL) and protein (0.17 mg/mL) contents were recorded in calli grown on 0.04% PF-68. Furthermore, enhanced expression of sucrose synthase (2.65-folds) and NADH-dependent glutamate synthase (1.86-folds) genes in calli grown on 0.04% PF-68 also correlates with enhanced callus proliferation. In contrast, high concentration of PF-68 (0.10%) recorded highest amount of phenolic (0.74 mg/mL), flavonoid (0.08 mg/mL), and hydrogen peroxide content (0.06 mg/mL) as compared to other treatment groups indicates activation of plant defence mechanism towards stress. Similarly, high expression of 4-coumarate:CoA ligase 3 (1.28-folds), chalcone-flavonone isomerase (1.65-folds) and ascorbate peroxidase (1.61-folds) genes were observed in calli grown on 0.10% PF-68 further supports increasing stress caused by the high concentration of PF-68. Taken together, our study revealed that optimum concentration of PF-68 could improve recalcitrant rice callus proliferation via enhanced sugar metabolism and amino acid biosynthesis which are crucial towards plant growth and development. However, at high concentration, PF-68 induces stress in plant which enhance the production of secondary metabolite to maintain cellular homeostasis.
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Affiliation(s)
- Andrew De-Xian Kok
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, Selangor Malaysia
| | - Wan Muhamad Asrul Nizam Wan Abdullah
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, Selangor Malaysia
| | - Ngai-Paing Tan
- Department of Land Management, Faculty of Agriculture, Universiti Putra Malaysia, Serdang, Selangor Malaysia
| | - Janna Ong-Abdullah
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, Selangor Malaysia
| | - Rogayah Sekeli
- Biotechnology and Nanotechnology Research Centre, Malaysian Agricultural Research and Development Institute (MARDI), Kuala Lumpur, Malaysia
| | - Chien-Yeong Wee
- Biotechnology and Nanotechnology Research Centre, Malaysian Agricultural Research and Development Institute (MARDI), Kuala Lumpur, Malaysia
| | - Kok-Song Lai
- Health Sciences Division, Abu Dhabi Women’s College, Higher Colleges of Technology, 41012 Abu Dhabi, United Arab Emirates
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8
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Narayanappa AT, Mwilu S, Holdread S, Hammett K, Bu G, Dodson EC, Brooks JW. A rapid cell-based assay for determining poloxamer quality in CHO suspension cell culture. Biotechniques 2019; 67:98-109. [PMID: 31347927 DOI: 10.2144/btn-2019-0070] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Poloxamers are water-soluble polymers that are widely used in cell culture bioprocessing to protect cells against shearing forces. Use of poor-quality poloxamers may lead to a drastic reduction in cell growth, viabilities and productivities in cell culture-based manufacturing. In order to evaluate poloxamer quality and promote more consistent performance, a rapid cell membrane adhesion to hydrocarbon assay was developed based on the adhesive properties of cell membranes to selective hydrocarbons. The assay can identify a poor-performing poloxamer characterized by significant drop in viable cell density and percent viability. The assay was verified across multiple good and bad poloxamer lots, and the results were in agreement with established cell growth and high-performance liquid chromatography assays.
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Affiliation(s)
| | - Sam Mwilu
- Advanced Bioprocessing, Thermo Fisher Scientific, 250 Schilling Circle, Hunt Valley, MD 21030, USA
| | - Stacy Holdread
- Advanced Bioprocessing, Thermo Fisher Scientific, 250 Schilling Circle, Hunt Valley, MD 21030, USA
| | - Kimesha Hammett
- Advanced Bioprocessing, Thermo Fisher Scientific, 250 Schilling Circle, Hunt Valley, MD 21030, USA
| | - George Bu
- Advanced Bioprocessing, Thermo Fisher Scientific, 250 Schilling Circle, Hunt Valley, MD 21030, USA
| | - Elizabeth C Dodson
- Advanced Bioprocessing, Thermo Fisher Scientific, 250 Schilling Circle, Hunt Valley, MD 21030, USA
| | - James W Brooks
- Advanced Bioprocessing, Thermo Fisher Scientific, 250 Schilling Circle, Hunt Valley, MD 21030, USA
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9
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Numerical Simulation of Bubble-Liquid Two-Phase Turbulent Flows in Shallow Bioreactor. ENERGIES 2019. [DOI: 10.3390/en12122269] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
An improved second-order moment bubble-liquid two-phase turbulent model is developed to predict the hydrodynamic characteristics of the shallow bioreactor using two height-to-diameter ratios of H/D = 1.4 and H/D = 2.9. The two-phase hydrodynamic parameters, the bubble normal and shear stress, the bubble energy dissipation rate, the bubble turbulent kinetic energy, etc. were numerically simulated. These parameters increased along with flow direction and constituted a threat to cells living at far distance away from the gas jetting inlet regions, rather than a finding of higher cell damage at near the jetting inlet region, as reported by Babosa et al. 2003. A new correlation named the turbulent energy production of bubble-liquid two-phase flow was proposed to successfully verify this experimental observation. A smaller H/D ratio makes more contributions to the generation of lower turbulent energy productions, which are in favor of the alleviation of cell damage. The extremely long and narrow shape of the bioreactor is deteriorative for cell living.
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10
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López-Rosales L, Sánchez-Mirón A, Contreras-Gómez A, García-Camacho F, Battaglia F, Zhao L, Molina-Grima E. Characterization of bubble column photobioreactors for shear-sensitive microalgae culture. BIORESOURCE TECHNOLOGY 2019; 275:1-9. [PMID: 30572257 DOI: 10.1016/j.biortech.2018.12.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 12/04/2018] [Accepted: 12/05/2018] [Indexed: 06/09/2023]
Abstract
The shear-sensitive marine algal dinoflagellate Karlodinium veneficum was grown in a cylindrical bubble column photobioreactor with an internal diameter of 0.044 m. Initial liquid height varied from 0.5 to 1.75 m, superficial gas velocities from 0.0014 to 0.0057 ms-1, and nozzle diameter from 1 to 2.5 mm. Computational fluid dynamics was used to characterize the flow hydrodynamics and energy dissipation rates. Experimental gas holdup and volumetric mass transfer coefficient strongly depended on the liquid height and correlated well with the Froude number. Energy dissipation near the head space (EDtop) was one order of magnitude higher than the average energy dissipation in the whole reactor (EDwhole), and the value in the sparger zone (EDspar) was one order of magnitude higher than EDtop. Cultures of K. veneficum were limited by CO2 transfer at low EDwhole and severely stressed above a critical value of EDwhole.
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Affiliation(s)
| | - Asterio Sánchez-Mirón
- Dept. of Chemical Engineering, University of Almería, 04120 Almería, Spain; Research Center in Agrifood Biotechnology, University of Almería, 04120 Almería, Spain.
| | | | - Francisco García-Camacho
- Dept. of Chemical Engineering, University of Almería, 04120 Almería, Spain; Research Center in Agrifood Biotechnology, University of Almería, 04120 Almería, Spain
| | - Francine Battaglia
- Department of Mechanical and Aerospace Engineering, University at Buffalo, NY 14260, USA
| | - Lei Zhao
- Department of Mechanical Engineering, Virginia Tech, Blacksburg, VA 24061, USA
| | - Emilio Molina-Grima
- Dept. of Chemical Engineering, University of Almería, 04120 Almería, Spain; Research Center in Agrifood Biotechnology, University of Almería, 04120 Almería, Spain
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11
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He C, Ye P, Wang H, Liu X, Li F. A systematic mass-transfer modeling approach for mammalian cell culture bioreactor scale-up. Biochem Eng J 2019. [DOI: 10.1016/j.bej.2018.09.019] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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12
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Sandner V, Pybus LP, McCreath G, Glassey J. Scale-Down Model Development in ambr systems: An Industrial Perspective. Biotechnol J 2018; 14:e1700766. [PMID: 30350921 DOI: 10.1002/biot.201700766] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Revised: 10/16/2018] [Indexed: 11/08/2022]
Abstract
High-Throughput (HT) technologies such as miniature bioreactors (MBRs) are increasingly employed within the biopharmaceutical manufacturing industry. Traditionally, these technologies have been utilized for discrete screening approaches during pre-clinical development (e.g., cell line selection and process optimization). However, increasing interest is focused towards their use during late clinical phase process characterization studies as a scale-down model (SDM) of the cGMP manufacturing process. In this review, the authors describe a systematic approach toward SDM development in one of the most widely adopted MBRs, the ambr 15 and 250 mL (Sartorius Stedim Biotech) systems. Recent efforts have shown promise in qualifying ambr systems as SDMs to support more efficient, robust and safe biomanufacturing processes. The authors suggest that combinatorial improvements in process understanding (matching of mass transfer and cellular stress between scales through computational fluid dynamics and in vitro analysis), experimental design (advanced risk assessment and statistical design of experiments), and data analysis (combining uni- and multi-variate techniques) will ultimately yield ambr SDMs applicable for future regulatory submissions.
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Affiliation(s)
- Viktor Sandner
- Process Design, Process Development, FUJIFILM Diosynth Biotechnologies, Belasis Avenue, Billingham, TS23 1LH, United Kingdom.,School Engineering, Merz Court University of Newcastle, Newcastle Upon Tyne, NE1 7RU, United Kingdom
| | - Leon P Pybus
- Mammalian Cell Culture, Process Development, FUJIFILM Diosynth Biotechnologies, Belasis Avenue, Billingham, TS23 1LH, United Kingdom
| | - Graham McCreath
- Process Design, Process Development, FUJIFILM Diosynth Biotechnologies, Belasis Avenue, Billingham, TS23 1LH, United Kingdom
| | - Jarka Glassey
- School Engineering, Merz Court University of Newcastle, Newcastle Upon Tyne, NE1 7RU, United Kingdom
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Heathman TR, Nienow AW, Rafiq QA, Coopman K, Kara B, Hewitt CJ. Agitation and aeration of stirred-bioreactors for the microcarrier culture of human mesenchymal stem cells and potential implications for large-scale bioprocess development. Biochem Eng J 2018. [DOI: 10.1016/j.bej.2018.04.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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14
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Villiger TK, Neunstoecklin B, Karst DJ, Lucas E, Stettler M, Broly H, Morbidelli M, Soos M. Experimental and CFD physical characterization of animal cell bioreactors: From micro- to production scale. Biochem Eng J 2018. [DOI: 10.1016/j.bej.2017.12.004] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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15
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Determination of Effective Parameters for Alpha-Amylase Production in a Modified Rotating Drum Bioreactor. ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING 2018. [DOI: 10.1007/s13369-017-3055-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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16
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Quantifying the potential for bursting bubbles to damage suspended cells. Sci Rep 2017; 7:15102. [PMID: 29118382 PMCID: PMC5678173 DOI: 10.1038/s41598-017-14531-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Accepted: 10/09/2017] [Indexed: 11/12/2022] Open
Abstract
Bubbles that rise to the surface of a cell suspension can damage cells when they pop. This phenomenon is particularly problematic in the biotechnology industry, as production scale bioreactors require continuous injection of oxygen bubbles to maintain cell growth. Previous studies have linked cell damage to high energy dissipation rates (EDR) and have predicted that for small bubbles the EDR could exceed values that would kill many cells used in bioreactors, including Chinese Hamster Ovary (CHO) cells. However, it’s unclear how many cells would be damaged by a particular bursting bubble, or more precisely how much volume around the bubble experiences these large energy dissipation rates. Here we quantify these volumes using numerical simulations and demonstrate that even though the volume exceeding a particular EDR increases with bubble size, on a volume-to-volume basis smaller bubbles have a more significant impact. We validate our model with high-speed experiments and present our results in a non-dimensionalized framework, enabling predictions for a variety of liquids and bubble sizes. The results are not restricted to bubbles in bioreactors and may be relevant to a variety of applications ranging from fermentation processes to characterizing the stress levels experienced by microorganisms within the sea surface microlayer.
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17
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Chang D, Fox R, Hicks E, Ferguson R, Chang K, Osborne D, Hu W, Velev OD. Investigation of interfacial properties of pure and mixed poloxamers for surfactant-mediated shear protection of mammalian cells. Colloids Surf B Biointerfaces 2017; 156:358-365. [DOI: 10.1016/j.colsurfb.2017.05.040] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 05/10/2017] [Accepted: 05/13/2017] [Indexed: 11/27/2022]
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18
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Impact of Pluronic ® F68 on hollow fiber filter-based perfusion culture performance. Bioprocess Biosyst Eng 2017; 40:1317-1326. [PMID: 28577048 DOI: 10.1007/s00449-017-1790-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2017] [Accepted: 05/24/2017] [Indexed: 10/19/2022]
Abstract
High cell density is an important factor in achieving high bioreactor productivity. To meet the oxygen demand with density at >100 × 106 cells/mL, a frit sparger is often used. In this study, the impact of Pluronic® F68 on a perfusion process using a frit sparger was studied. The perfusion process was developed using an alternating tangential flow device with a 0.2 µm PES hollow fiber filter. Pluronic® F68 at 2 g/L was sufficient in preventing cell damage at gas flow rate of ~0.20 vvm from a drilled hole sparger (0.5 mm) but inadequate at ~0.025 vvm from a frit sparger (20 µm). Increase of Pluronic® F68 concentration to 5 g/L prevented cell death at up to ~0.10 vvm from the frit sparger and was able to maintain high cell density at high viability in the range of 60-80 × 106 cells/mL. Such positive effect was demonstrated in both 3- and 200-L bioreactors. Supplementing additional Pluronic® F68 was also effective in restoring cell growth/viability from low viability cultures. Increased Pluronic® F68 concentration had no adverse impact on target antibody, HCP, and Pluronic® F68 transmissions.
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19
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Pawar SB. Process Engineering Aspects of Vertical Column Photobioreactors for Mass Production of Microalgae. CHEMBIOENG REVIEWS 2016. [DOI: 10.1002/cben.201600003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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20
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Neunstoecklin B, Villiger TK, Lucas E, Stettler M, Broly H, Morbidelli M, Soos M. Pilot-scale verification of maximum tolerable hydrodynamic stress for mammalian cell culture. Appl Microbiol Biotechnol 2015; 100:3489-98. [DOI: 10.1007/s00253-015-7193-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Revised: 11/17/2015] [Accepted: 11/20/2015] [Indexed: 10/22/2022]
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21
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Villiger TK, Morbidelli M, Soos M. Experimental determination of maximum effective hydrodynamic stress in multiphase flow using shear sensitive aggregates. AIChE J 2015. [DOI: 10.1002/aic.14753] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Thomas K. Villiger
- Dept. of Chemistry and Applied Biosciences; Institute for Chemical and Bioengineering; ETH Zurich 8093 Zurich Switzerland
| | - Massimo Morbidelli
- Dept. of Chemistry and Applied Biosciences; Institute for Chemical and Bioengineering; ETH Zurich 8093 Zurich Switzerland
| | - Miroslav Soos
- Dept. of Chemistry and Applied Biosciences; Institute for Chemical and Bioengineering; ETH Zurich 8093 Zurich Switzerland
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22
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Tharmalingam T, Goudar CT. Evaluating the impact of high Pluronic® F68 concentrations on antibody producing CHO cell lines. Biotechnol Bioeng 2014; 112:832-7. [PMID: 25384465 DOI: 10.1002/bit.25491] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2014] [Revised: 09/13/2014] [Accepted: 11/03/2014] [Indexed: 02/03/2023]
Abstract
Pluronic® F68 (P-F68) is an important component of chemically-defined cell culture medium because it protects cells from hydrodynamic and bubble-induced shear in the bioreactor. While P-F68 is typically used in cell culture medium at a concentration of 1 g/L (0.1%), higher concentrations can offer additional shear protection and have also been shown to be beneficial during cryopreservation. Recent industry experience with variability in P-F68-associated shear-protection has opened up the possibility of elevated P-F68 concentrations in cell culture media, a topic that has not been previously explored in the context of industrial cell culture processes. Recognizing this gap, we first evaluated the effect of 1-5 g/L P-F68 concentrations in shake flask cultures over ten 3-day passages for cell lines A and B. Increase in terminal cell density and cell size was seen over time at higher P-F68 concentrations but protein productivity was not impacted. Results from this preliminary screening study suggested no adverse impact of high P-F68 concentrations. Subsequently fed-batch bioreactor experiments were conducted at 1 and 5 g/L P-F68 concentrations with both cell lines where cell growth, viability, metabolism, and product quality were examined under process conditions reflective of a commercial process. Results from these bioreactor experiments confirmed findings from the preliminary screen and also indicated no impact of elevated P-F68 concentration on product quality. If additional shear protection is desired, either due to raw material variability, cell line sensitivity, or a high-shear cell culture process, our results suggest this can be accomplished by elevating the P-F68 concentration in the cell culture medium without impacting cell culture performance and product quality.
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Affiliation(s)
- Tharmala Tharmalingam
- Cell Science & Technology, Process & Product Development, Amgen Inc. One Amgen Center Drive, Thousand Oaks, 91320, California
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23
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Tescione L, Lambropoulos J, Paranandi MR, Makagiansar H, Ryll T. Application of bioreactor design principles and multivariate analysis for development of cell culture scale down models. Biotechnol Bioeng 2014; 112:84-97. [DOI: 10.1002/bit.25330] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Revised: 06/01/2014] [Accepted: 06/30/2014] [Indexed: 11/10/2022]
Affiliation(s)
- Lia Tescione
- Biogen Idec, Cell Culture Development; 14 Cambridge Center Cambridge Massachusetts 02142
| | - James Lambropoulos
- Biogen Idec, Cell Culture Development; 14 Cambridge Center Cambridge Massachusetts 02142
| | - Madhava Ram Paranandi
- Biogen Idec, Cell Culture Development; 14 Cambridge Center Cambridge Massachusetts 02142
| | - Helena Makagiansar
- Biogen Idec, Cell Culture Development; 14 Cambridge Center Cambridge Massachusetts 02142
| | - Thomas Ryll
- Biogen Idec, Cell Culture Development; 14 Cambridge Center Cambridge Massachusetts 02142
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24
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Peng H, Hall KM, Clayton B, Wiltberger K, Hu W, Hughes E, Kane J, Ney R, Ryll T. Development of small scale cell culture models for screening poloxamer 188 lot-to-lot variation. Biotechnol Prog 2014; 30:1411-8. [DOI: 10.1002/btpr.1967] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Revised: 06/20/2014] [Indexed: 12/12/2022]
Affiliation(s)
- Haofan Peng
- Cell Culture Development, Biogen Idec; Research Triangle Park; 5000 Davis Drive NC 27709
| | - Kaitlyn M. Hall
- Cell Culture Development, Biogen Idec; Research Triangle Park; 5000 Davis Drive NC 27709
| | - Blake Clayton
- Cell Culture Development, Biogen Idec; Research Triangle Park; 5000 Davis Drive NC 27709
| | - Kelly Wiltberger
- Cell Culture Development, Biogen Idec; Research Triangle Park; 5000 Davis Drive NC 27709
| | - Weiwei Hu
- Cell Culture Development, Biogen Idec; Research Triangle Park; 5000 Davis Drive NC 27709
| | - Erik Hughes
- Manufacturing Sciences, Biogen Idec; Research Triangle Park; NC 27709
| | - John Kane
- Manufacturing Sciences, Biogen Idec; Research Triangle Park; NC 27709
| | - Rachel Ney
- Manufacturing Sciences, Biogen Idec; Research Triangle Park; NC 27709
| | - Thomas Ryll
- Cell Culture Development, Biogen Idec; Cambridge MA 02142
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25
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Walls PLL, Bird JC, Bourouiba L. Moving with bubbles: a review of the interactions between bubbles and the microorganisms that surround them. Integr Comp Biol 2014; 54:1014-25. [PMID: 25096288 DOI: 10.1093/icb/icu100] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Bubbles are ubiquitous in biological environments, emerging during the complex dynamics of waves breaking in the open oceans or being intentionally formed in bioreactors. From formation, through motion, until death, bubbles play a critical role in the oxygenation and mixing of natural and artificial ecosystems. However, their life is also greatly influenced by the environments in which they emerge. This interaction between bubbles and microorganisms is a subtle affair in which surface tension plays a critical role. Indeed, it shapes the role of bubbles in mixing or oxygenating microorganisms, but also determines how microorganisms affect every stage of the bubble's life. In this review, we guide the reader through the life of a bubble from birth to death, with particular attention to the microorganism-bubble interaction as viewed through the lens of fluid dynamics.
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Affiliation(s)
- Peter L L Walls
- *Boston University, 730 Commonwealth Avenue, Boston, MA 02215, USA; Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - James C Bird
- *Boston University, 730 Commonwealth Avenue, Boston, MA 02215, USA; Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Lydia Bourouiba
- *Boston University, 730 Commonwealth Avenue, Boston, MA 02215, USA; Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
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26
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Liu Y, Li F, Hu W, Wiltberger K, Ryll T. Effects of bubble-liquid two-phase turbulent hydrodynamics on cell damage in sparged bioreactor. Biotechnol Prog 2013; 30:48-58. [DOI: 10.1002/btpr.1790] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2013] [Revised: 06/08/2013] [Accepted: 07/18/2013] [Indexed: 11/11/2022]
Affiliation(s)
- Yang Liu
- Dept. of Chemical and Bimolecular Engineering; North Carolina State University; Raleigh NC
| | - Fanxing Li
- Dept. of Chemical and Bimolecular Engineering; North Carolina State University; Raleigh NC
| | - Weiwei Hu
- Dept. of Cell Culture Development; Biogen Idec Inc., Research Triangle Park; NC
| | - Kelly Wiltberger
- Dept. of Cell Culture Development; Biogen Idec Inc., Research Triangle Park; NC
| | - Thomas Ryll
- Dept. of Cell Culture Development; Biogen Idec Inc.; Cambridge MA
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27
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Borchers S, Freund S, Rath A, Streif S, Reichl U, Findeisen R. Identification of growth phases and influencing factors in cultivations with AGE1.HN cells using set-based methods. PLoS One 2013; 8:e68124. [PMID: 23936299 PMCID: PMC3732265 DOI: 10.1371/journal.pone.0068124] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2012] [Accepted: 05/30/2013] [Indexed: 01/16/2023] Open
Abstract
Production of bio-pharmaceuticals in cell culture, such as mammalian cells, is challenging. Mathematical models can provide support to the analysis, optimization, and the operation of production processes. In particular, unstructured models are suited for these purposes, since they can be tailored to particular process conditions. To this end, growth phases and the most relevant factors influencing cell growth and product formation have to be identified. Due to noisy and erroneous experimental data, unknown kinetic parameters, and the large number of combinations of influencing factors, currently there are only limited structured approaches to tackle these issues. We outline a structured set-based approach to identify different growth phases and the factors influencing cell growth and metabolism. To this end, measurement uncertainties are taken explicitly into account to bound the time-dependent specific growth rate based on the observed increase of the cell concentration. Based on the bounds on the specific growth rate, we can identify qualitatively different growth phases and (in-)validate hypotheses on the factors influencing cell growth and metabolism. We apply the approach to a mammalian suspension cell line (AGE1.HN). We show that growth in batch culture can be divided into two main growth phases. The initial phase is characterized by exponential growth dynamics, which can be described consistently by a relatively simple unstructured and segregated model. The subsequent phase is characterized by a decrease in the specific growth rate, which, as shown, results from substrate limitation and the pH of the medium. An extended model is provided which describes the observed dynamics of cell growth and main metabolites, and the corresponding kinetic parameters as well as their confidence intervals are estimated. The study is complemented by an uncertainty and outlier analysis. Overall, we demonstrate utility of set-based methods for analyzing cell growth and metabolism under conditions of uncertainty.
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Affiliation(s)
- Steffen Borchers
- Institute for Systems Theory and Automatic Control, Otto-von-Guericke University, Magdeburg, Germany
- International Max Planck Research School, Magdeburg, Germany
| | - Susann Freund
- International Max Planck Research School, Magdeburg, Germany
- Max Planck Institute for Dynamics of Complex Technical Systems, Magdeburg, Germany
- Institute of Process Engineering, Otto-von-Guericke University, Magdeburg, Germany
| | - Alexander Rath
- Max Planck Institute for Dynamics of Complex Technical Systems, Magdeburg, Germany
| | - Stefan Streif
- Institute for Systems Theory and Automatic Control, Otto-von-Guericke University, Magdeburg, Germany
| | - Udo Reichl
- Max Planck Institute for Dynamics of Complex Technical Systems, Magdeburg, Germany
- Institute of Process Engineering, Otto-von-Guericke University, Magdeburg, Germany
| | - Rolf Findeisen
- Institute for Systems Theory and Automatic Control, Otto-von-Guericke University, Magdeburg, Germany
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28
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Sieblist C, Jenzsch M, Pohlscheidt M. Influence of pluronic F68 on oxygen mass transfer. Biotechnol Prog 2013; 29:1278-88. [PMID: 23843368 DOI: 10.1002/btpr.1770] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2012] [Revised: 05/27/2013] [Accepted: 05/17/2013] [Indexed: 11/09/2022]
Abstract
Pluronic F68 is one of the most used shear protecting additives in cell culture cultivations. It is well known from literature that such surface-active surfactants lower the surface tension at the gas-liquid interface, which influences the mass transfer. In this study, the effect of Pluronic F68 on oxygen mass transfer in aqueous solutions was examined. Therefore, the gassing in/gassing out method and bubble size measurements were used. At low concentrations of 0.02 g/L, a 50% reduction on mass transfer was observed for all tested spargers and working conditions. An explanation of the observed effects by means of Higbie's penetration or Dankwerts surface renewal theory was applied. It could be demonstrated that the suppressed movement of the bubble surface layer is the main cause for the significant drop down of the kL a-values. For Pluronic F68 concentrations above 0.1 g/L, it was observed that it comes to changes in bubble appearance and bubble size strongly dependent on the sparger type. By using the bubble size measurement data, it could be shown that only small changes in mass transfer coefficient (kL ) take place above the critical micelle concentration. Further changes on overall mass transfer at higher Pluronic F68 concentrations are mainly based on increasing of gas holdup and, more importantly, by increasing of the surface area available for mass transfer.
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Affiliation(s)
- Christian Sieblist
- Pharmaceutical Biotech Production, Roche Diagnostics GmbH, Penzberg, Germany
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29
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Freund S, Rath A, Barradas OP, Skerhutt E, Scholz S, Niklas J, Sandig V, Rose T, Heinzle E, Noll T, Pörtner R, Zeng AP, Reichl U. Batch-to-batch variability of two human designer cell lines - AGE1.HN and AGE1.HN.AAT - carried out by different laboratories under defined culture conditions using a mathematical model. Eng Life Sci 2013. [DOI: 10.1002/elsc.201200111] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- Susann Freund
- Bioprocess Engineering; Max Planck Institute for Dynamics of Complex Technical Systems; Magdeburg Germany
| | - Alexander Rath
- Bioprocess Engineering; Max Planck Institute for Dynamics of Complex Technical Systems; Magdeburg Germany
| | - Oscar Platas Barradas
- Institute of Bioprocess and Biosystems Engineering; Hamburg University of Technology; Hamburg Germany
| | - Eva Skerhutt
- Institute of Cell Culture Technology; University of Bielefeld; Bielefeld Germany
| | - Sebastian Scholz
- Institute of Cell Culture Technology; University of Bielefeld; Bielefeld Germany
| | - Jens Niklas
- Biochemical Engineering Institute; Saarland University; Saarbrücken Germany
| | | | | | - Elmar Heinzle
- Biochemical Engineering Institute; Saarland University; Saarbrücken Germany
| | - Thomas Noll
- Institute of Cell Culture Technology; University of Bielefeld; Bielefeld Germany
| | - Ralf Pörtner
- Institute of Bioprocess and Biosystems Engineering; Hamburg University of Technology; Hamburg Germany
| | - An Ping Zeng
- Institute of Bioprocess and Biosystems Engineering; Hamburg University of Technology; Hamburg Germany
| | - Udo Reichl
- Bioprocess Engineering; Max Planck Institute for Dynamics of Complex Technical Systems; Magdeburg Germany
- Bioprocess Engineering; Otto-von-Guericke University; Magdeburg Germany
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30
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Velez-Suberbie ML, Tarrant RDR, Tait AS, Spencer DIR, Bracewell DG. Impact of aeration strategy on CHO cell performance during antibody production. Biotechnol Prog 2012; 29:116-26. [PMID: 23074084 DOI: 10.1002/btpr.1647] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2012] [Revised: 10/12/2012] [Indexed: 12/20/2022]
Abstract
Stirred tank bioreactors using suspension adapted mammalian cells are typically used for the production of complex therapeutic proteins. The hydrodynamic conditions experienced by cells within this environment have been shown to directly impact growth, productivity, and product quality and therefore an improved understanding of the cellular response is critical. Here we investigate the sub-lethal effects of different aeration strategies on Chinese hamster ovary cells during monoclonal antibody production. Two gas delivery systems were employed to study the presence and absence of the air-liquid interface: bubbled direct gas sparging and a non-bubbled diffusive silicone membrane system. Additionally, the effect of higher gas flow rate in the sparged bioreactor was examined. Both aeration systems were run using chemically defined media with and without the shear protectant Pluronic F-68 (PF-68). Cells were unable to grow with direct gas sparging without PF-68; however, when a silicone membrane aeration system was implemented growth was comparable to the sparged bioreactor with PF-68, indicating the necessity of shear protectants in the presence of bubbles. The cultures exposed to increased hydrodynamic stress were shown by flow cytometry to have decreased F-actin intensity within the cytoskeleton and enter apoptosis earlier. This indicates that these conditions elicit a sub-lethal physiological change in cells that would not be detected by the at-line assays which are normally implemented during cell culture. These physiological changes only result in a difference in continuous centrifugation performance under high flow rate conditions. Product quality was more strongly affected by culture age than the hydrodynamic conditions tested.
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Affiliation(s)
- M Lourdes Velez-Suberbie
- The Advanced Centre of Biochemical Engineering, Dept. of Biochemical Engineering, University College London, Torrington Place, London, WC1E 7JE, U.K
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31
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Kondragunta B, Han J, Joshi BH, Brorson KA, Puri RK, Uplekar S, Moreira AR, Rao G. Genomic analysis of a hybridoma batch cell culture metabolic status in a standard laboratory 5 L bioreactor. Biotechnol Prog 2012; 28:1126-37. [PMID: 22837152 DOI: 10.1002/btpr.1605] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2012] [Revised: 07/11/2012] [Indexed: 01/14/2023]
Abstract
Currently, there is a gap in the knowledge of the culture responses to controlled bioreactor environment during the course of batch cell culture from early exponential phase to stationary-phase. If available, such information could be used to designate gene transcripts for predicting cell status and as a quality predictor for a controlled bioreactor. In this study, we used oligonucleotide microarrays to obtain baseline gene expression profiles during the time-course of a hybridoma batch cell culture in a 5 L bench-scale bioreactor. Gene expression changes that were up or down modulated from early-to-late in batch culture, as well as invariant gene profiles with significant expression were identified using microarray. Typical cellular functions that seemed to be correlated with transcriptomics were oxidative stress response, DNA damage response, apoptosis, and cellular metabolism. As confirmatory evidence, microarray findings were verified with a more rigorous semiquantitative gene-specific Reverse transcriptase-polymerase chain reaction (RT-PCR). The results of this study suggest that under predefined bioreactor culture conditions, significant gene changes from lag to log to stationary phase could be identified, which could then be used to track the culture state.
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Affiliation(s)
- Bhargavi Kondragunta
- Center for Advanced Sensor Technology and Dept. of Chemical and Biochemical Engineering, University of Maryland, Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250, USA
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32
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Hu W, Berdugo C, Chalmers JJ. The potential of hydrodynamic damage to animal cells of industrial relevance: current understanding. Cytotechnology 2011; 63:445-60. [PMID: 21785843 PMCID: PMC3176934 DOI: 10.1007/s10616-011-9368-3] [Citation(s) in RCA: 102] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2008] [Accepted: 06/11/2011] [Indexed: 11/25/2022] Open
Abstract
Suspension animal cell culture is now routinely scaled up to bioreactors on the order of 10,000 L, and greater, to meet commercial demand. However, the concern of the 'shear sensitivity' of animal cells still remains, not only within the bioreactor, but also in the downstream processing. As the productivities continue to increase, titer of ~10 g/L are now reported with cell densities greater than 2 × 10(7) cells/mL. Such high, and potentially higher cell densities will inevitably translate to increased demand in mass transfer and mixing. In addition, achieving productivity gains in both the upstream stage and downstream processes can subject the cells to aggressive environments such as those involving hydrodynamic stresses. The perception of 'shear sensitivity' has historically put an arbitrary upper limit on agitation and aeration in bioreactor operation; however, as cell densities and productivities continue to increase, mass transfer requirements can exceed those imposed by these arbitrary low limits. Therefore, a better understanding of how animal cells, used to produce therapeutic products, respond to hydrodynamic forces in both qualitative and quantitative ways will allow an experimentally based, higher, "upper limit" to be created to guide the design and operation of future commercial, large scale bioreactors. With respect to downstream hydrodynamic conditions, situations have already been achieved in which practical limits with respect to hydrodynamic forces have been experienced. This review mainly focuses on publications from both the academy and industry regarding the effect of hydrodynamic forces on industrially relevant animal cells, and not on the actual scale-up of bioreactors. A summary of implications and remaining challenges will also be presented.
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Affiliation(s)
- Weiwei Hu
- Cell Culture Development, Biogen Idec Inc., 5000 Davis Drive, RTP, NC 27709 USA
| | - Claudia Berdugo
- Scientist / Research & Development, BD Biosciences, 54 Loveton Circle, Sparks, MD 21152 USA
| | - Jeffrey J. Chalmers
- William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, 140 West 19th Ave., Columbus, OH 43210 USA
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Sandadi S, Pedersen H, Bowers JS, Rendeiro D. A comprehensive comparison of mixing, mass transfer, Chinese hamster ovary cell growth, and antibody production using Rushton turbine and marine impellers. Bioprocess Biosyst Eng 2011; 34:819-32. [PMID: 21505815 DOI: 10.1007/s00449-011-0532-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2010] [Accepted: 02/17/2011] [Indexed: 11/30/2022]
Abstract
Large scale production of monoclonal antibodies has been accomplished using bioreactors with different length to diameter ratios, and diverse impeller and sparger designs. The differences in these physical attributes often result in dissimilar mass transfer, mechanical stresses due to turbulence and mixing inside the bioreactor that may lead to disparities in cell growth and antibody production. A rational analysis of impeller design parameters on cell growth, protein expression levels and subsequent antibody production is needed to understand such differences. The purpose of this study was to examine the impact of Rushton turbine and marine impeller designs on Chinese hamster ovary (CHO) cell growth and metabolism, and antibody production and quality. Experiments to evaluate mass transfer and mixing characteristics were conducted to determine if the nutrient requirements of the culture would be met. The analysis of mixing times indicated significant differences between marine and Rushton turbine impellers at the same power input per unit volume of liquid (P/V). However, no significant differences were observed between the two impellers at constant P/V with respect to oxygen and carbon dioxide mass transfer properties. Experiments were conducted with CHO cells to determine the impact of different flow patterns arising from the use of different impellers on cell growth, metabolism and antibody production. The analysis of cell culture data did not indicate any significant differences in any of the measured or calculated variables between marine and Rushton turbine impellers. More importantly, this study was able to demonstrate that the quality of the antibody was not altered with a change in the impeller geometry.
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Affiliation(s)
- Sandeepa Sandadi
- BioProcess Development, Merck Research Laboratories, 1011 Morris Avenue, Union, NJ 07083, USA.
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34
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Clincke MF, Guedon E, Yen FT, Ogier V, Roitel O, Goergen JL. Effect of surfactant pluronic F-68 on CHO cell growth, metabolism, production, and glycosylation of human recombinant IFN-γ in mild operating conditions. Biotechnol Prog 2010; 27:181-90. [PMID: 21312365 DOI: 10.1002/btpr.503] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2010] [Revised: 06/24/2010] [Indexed: 11/11/2022]
Abstract
The control of glycosylation to satisfy regulatory requirements and quality consistency of recombinant proteins produced by different processes has become an important issue. With two N-glycosylation sites, γ-interferon (IFN-γ) can be seen as a prototype of a recombinant therapeutic glycoprotein for this purpose. The effect of the nonionic surfactant Pluronic F-68 (PF-68) on cell growth and death was investigated, as well as production and glycosylation of recombinant IFN-γ produced by a CHO cell line that was maintained in a rich protein-free medium in the absence or presence of low agitation. Under these conditions, a dose-dependent effect of PF-68 (0-0.1%) was shown not only to significantly enhance growth but also to reduce cell lysis. Interestingly, supplementing the culture medium with PF-68 led to increased IFN-γ production as a result of both higher cell densities and a higher specific production rate of IFN-γ. If cells were grown with agitation, lack of PF-68 in the culture medium decreased the fraction of the fully glycosylated IFN-γ glycoform (2N) from 80% to 65-70% during the initial period. This effect appeared to be due to a lag phase in cell growth observed during this period. Finally, a global kinetic study of CHO cell metabolism indicated higher efficiency in the utilization of the two major carbon substrates when cultures were supplemented with PF-68. Therefore, these results highlight the importance of understanding how media surfactant can affect cell growth as well as cell death and the product quality of a recombinant glycoprotein expressed in CHO cell cultures.
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Affiliation(s)
- Marie-Françoise Clincke
- Laboratoire Réactions et Génie des Procédés, UPR-CNRS 3349, ENSAIA-INPL, Nancy Université, Vandoeuvre-lès-Nancy, France
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35
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Toye D, Galifi A, Salmon T, Marchot P, Verdin E, Crine M. Influence of medium composition on oxygen transfer rate in animal cell culture. CAN J CHEM ENG 2010. [DOI: 10.1002/cjce.20302] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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36
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Xing Z, Kenty BM, Li ZJ, Lee SS. Scale-up analysis for a CHO cell culture process in large-scale bioreactors. Biotechnol Bioeng 2009; 103:733-46. [PMID: 19280669 DOI: 10.1002/bit.22287] [Citation(s) in RCA: 133] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Bioprocess scale-up is a fundamental component of process development in the biotechnology industry. When scaling up a mammalian cell culture process, it is important to consider factors such as mixing time, oxygen transfer, and carbon dioxide removal. In this study, cell-free mixing studies were performed in production scale 5,000-L bioreactors to evaluate scale-up issues. Using the current bioreactor configuration, the 5,000-L bioreactor had a lower oxygen transfer coefficient, longer mixing time, and lower carbon dioxide removal rate than that was observed in bench scale 5- and 20-L bioreactors. The oxygen transfer threshold analysis indicates that the current 5,000-L configuration can only support a maximum viable cell density of 7 x 10(6) cells mL(-1). Moreover, experiments using a dual probe technique demonstrated that pH and dissolved oxygen gradients may exist in 5,000-L bioreactors using the current configuration. Empirical equations were developed to predict mixing time, oxygen transfer coefficient, and carbon dioxide removal rate under different mixing-related engineering parameters in the 5,000-L bioreactors. These equations indicate that increasing bottom air sparging rate is more efficient than increasing power input in improving oxygen transfer and carbon dioxide removal. Furthermore, as the liquid volume increases in a production bioreactor operated in fed-batch mode, bulk mixing becomes a challenge. The mixing studies suggest that the engineering parameters related to bulk mixing and carbon dioxide removal in the 5,000-L bioreactors may need optimizing to mitigate the risk of different performance upon process scale-up.
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Affiliation(s)
- Zizhuo Xing
- Process Sciences, Biologics Manufacturing and Process Development, Worldwide Medicines Group, Bristol-Myers Squibb Company, Syracuse, NY 13221-4755, USA
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Abstract
The specific characteristics of mammalian cells discussed in Chap. 2 require adapted solutions for bioreactor design and operation. Especially, cell damage by shear stress and aeration has to be considered. Therefore this chapter starts with a detailed discussion of shear stress effects on mammalian cells (anchorage-dependent and suspendable cells) in model systems and bioreactors, respectively, and consequences for reactor design. Appropriate oxygen supply is another critical issue, as adapted oxygen supply systems are required. Techniques for immobilization of cells, either grown on microcarriers in suspension culture or within macroporous carriers in fixed bed or fluidized bed reactors, are discussed as well. With respect to the operation of bioreactors, the characteristics of different culture modes (batch, fed-batch, chemostat, perfusion) are introduced and practical examples are given. Finally, concepts for monitoring of bioreactors, including offline and online methods as well as control loops (e.g. O2, pH), are considered.
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Affiliation(s)
- P. Czermak
- Institute of Biopharmaceutical Technology, University of Applied Sciences Giessen-Friedberg, Giessen, Germany ,Department of Chemical Engineering, Kansas State University, Durland Hall 105, KS 66506-5102 Manhattan, USA
| | - R. Pörtner
- Institute of Bioprocess and Biosystems Engineering, Hamburg University of Technology (TUHH), Denickestr. 15, D-21073 Hamburg, Germany
| | - A. Brix
- Department of Chemical Engineering, Kansas State University, Durland Hall 105, KS 66506-5102 Manhattan, USA
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An investigation of small-molecule surfactants to potentially replace pluronic F-68 for reducing bubble-associated cell damage. Biotechnol Bioeng 2008; 101:119-27. [DOI: 10.1002/bit.21872] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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Tharmalingam T, Ghebeh H, Wuerz T, Butler M. Pluronic enhances the robustness and reduces the cell attachment of mammalian cells. Mol Biotechnol 2008; 39:167-77. [PMID: 18327558 DOI: 10.1007/s12033-008-9045-8] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
The addition of the non-ionic surfactant, Pluronic F-68, to serum-free CHO cultures causes multi-functional effects that enhance cell yield in agitated cultures and reduce cell adhesion in stationary cultures. Three independent CHO cell lines were subjected to high liquid shear in assay systems that either included or excluded a liquid-gas interface. In the absence of Pluronic, there was a loss in cell viability in either assay system, although there was an intrinsic variability in sensitivity of the cell lines to shear damage. Supplementation with Pluronic prevented loss of cell viability, indicating protection in either a gas sparged or bubble-free environment. However, we found no evidence of long-term protection of cells once Pluronic was removed. Pluronic was capable of repairing trypsin-damaged cells as evidenced by enhanced growth, reduced membrane porosity, and improved robustness under liquid shear. The proportion of adherent cells was reduced to a minimal level by the presence of Pluronic although its effect was rapidly reversible with a high proportion (70%) of adherent cells observed within a few culture passages of its removal. The observed effects of Pluronic on these cultures are compatible with a mechanism in which the polymer forms a protective layer on the cell membrane, which has a significantly lower hydrophobicity.
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Affiliation(s)
- T Tharmalingam
- Department of Microbiology, University of Manitoba, Manitoba, Winnipeg, Canada R3T 2N2
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Gigout A, Buschmann MD, Jolicoeur M. The fate of Pluronic F-68 in chondrocytes and CHO cells. Biotechnol Bioeng 2008; 100:975-87. [DOI: 10.1002/bit.21840] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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Weyand B, Israelowitz M, Schroeder H, Vogt P. Fluid Dynamics in Bioreactor Design: Considerations for the Theoretical and Practical Approach. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2008. [DOI: 10.1007/10_2008_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Koynov A, Tryggvason G, Khinast JG. Characterization of the localized hydrodynamic shear forces and dissolved oxygen distribution in sparged bioreactors. Biotechnol Bioeng 2007; 97:317-31. [PMID: 17154313 DOI: 10.1002/bit.21281] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Detailed, high-resolution numerical simulations of the bubbly flows, used for oxygen delivery and mixing in mammalian cell suspensions, have been performed. The hydrodynamics, shear and normal forces, mass transfer and mass transport from and around individual bubbles and bubble clusters were resolved for different operating conditions, that is, Weber, Morton, and Schmidt numbers. Suspended animal (e.g., mammalian, insect) cells are known to be susceptible to damage potentially leading to cell death, caused by hydrodynamic stresses and oxygen deprivation. Better knowledge of the magnitude of the shear forces and the extent of mixing of the dissolved oxygen in sparged bioreactors can have a significant impact on their future design and optimization. Therefore, the computed liquid-phase velocity fields were used to calculate and compare the local shear in different types of single bubble wakes and in bubble clusters. Oxygen mass transfer and dissolved oxygen transport were resolved to examine oxygen supply to the cells in the different types of flows.
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Affiliation(s)
- Athanas Koynov
- Department of Chemical and Biochemical Engineering, Rutgers University, Piscataway, New Jersey 08845-8058, USA
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Kim L, Toh YC, Voldman J, Yu H. A practical guide to microfluidic perfusion culture of adherent mammalian cells. LAB ON A CHIP 2007; 7:681-94. [PMID: 17538709 DOI: 10.1039/b704602b] [Citation(s) in RCA: 225] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Culturing cells at microscales allows control over microenvironmental cues, such as cell-cell and cell-matrix interactions; the potential to scale experiments; the use of small culture volumes; and the ability to integrate with microsystem technologies for on-chip experimentation. Microfluidic perfusion culture in particular allows controlled delivery and removal of soluble biochemical molecules in the extracellular microenvironment, and controlled application of mechanical forces exerted via fluid flow. There are many challenges to designing and operating a robust microfluidic perfusion culture system for routine culture of adherent mammalian cells. The current literature on microfluidic perfusion culture treats microfluidic design, device fabrication, cell culture, and micro-assays independently. Here we systematically present and discuss important design considerations in the context of the entire microfluidic perfusion culture system. These design considerations include the choice of materials, culture configurations, microfluidic network fabrication and micro-assays. We also present technical issues such as sterilization; seeding cells in both 2D and 3D configurations; and operating the system under optimized mass transport and shear stress conditions, free of air-bubbles. The integrative and systematic treatment of the microfluidic system design and fabrication, cell culture, and micro-assays provides novices with an effective starting point to build and operate a robust microfludic perfusion culture system for various applications.
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Affiliation(s)
- Lily Kim
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Rm 36-824, Cambridge, MA 02139, USA
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Radl S, Tryggvason G, Khinast JG. Flow and mass transfer of fully resolved bubbles in non-Newtonian fluids. AIChE J 2007. [DOI: 10.1002/aic.11211] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Afeyan NB, Cooney CL. Professor Daniel I.C. Wang: A legacy of education, innovation, publication, and leadership. Biotechnol Bioeng 2006; 95:206-217. [PMID: 16933287 DOI: 10.1002/bit.21078] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Noubar B Afeyan
- Flagship Ventures, One Memorial Drive, 7th Floor, Cambridge, Massachusetts
- Sloan School of Management, Massachusetts Institute of Technology, 50 Memorial Drive, Cambridge, Massachusetts
| | - Charles L Cooney
- Department of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139-4307
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Reactor engineering in large scale animal cell culture. Cytotechnology 2006; 50:9-33. [PMID: 19003068 DOI: 10.1007/s10616-006-9005-8] [Citation(s) in RCA: 205] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2006] [Accepted: 03/29/2006] [Indexed: 10/24/2022] Open
Abstract
This article mainly addresses the issues associated with the engineering of large-scale free suspension culture in agitated bioreactors >10,000 L because they have become the system of choice industrially. It is particularly concerned with problems that become increasingly important as the scale increases. However, very few papers have been written that are actually based on such large-scale studies and the few that do rarely address any of the issues quantitatively. Hence, it is necessary very often to extrapolate from small-scale work and this review tries to pull the two types of study together. It is shown that 'shear sensitivity' due to agitation and bursting bubbles is no longer considered a major problem. Homogeneity becomes increasingly important with respect to pH and nutrients at the largest scale and sub-surface feeding is recommended despite 'cleaning in place' concerns. There are still major questions with cell retention/recycle systems at these scales, either because of fouling, of capacity or of potential and different 'shear sensitivity' questions. Fed-batch operation gives rise to cell densities that have led to the use of oxygen and enriched air to meet oxygen demands. This strategy, in turn, gives rise to a CO(2) evolution rate that impacts on pH control, pCO(2) and osmolality. These interactions are difficult to resolve but if higher sparge and agitation intensities could be used to achieve the necessary oxygen transfer, the problem would largely disappear. Thus, the perception of 'shear sensitivity' is still impacting on the development of animal cell culture at the commercial scale. Microcarrier culture is also briefly addressed. Finally, some recommendations for bioreactor configuration and operating strategy are given.
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Lim SF, Chuan KH, Liu S, Loh SOH, Chung BYF, Ong CC, Song Z. RNAi suppression of Bax and Bak enhances viability in fed-batch cultures of CHO cells. Metab Eng 2006; 8:509-22. [PMID: 16860584 DOI: 10.1016/j.ymben.2006.05.005] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2006] [Revised: 05/11/2006] [Accepted: 05/31/2006] [Indexed: 11/17/2022]
Abstract
Bcl-2 family proteins play a crucial role in the regulation of the mitochondrial pathway that leads to apoptosis. Members of the Bcl-2 family can be divided into the anti-apoptotic proteins such as Bcl-2 and Bcl-X(L), and the pro-apoptotic proteins such as Bax and Bak and the BH3-only proteins. In this study, siRNA constructs to silence the Bax and Bak genes in Chinese hamster ovary (CHO) cells were generated. Stable CHO cell lines in which the expression of Bax and Bak were significantly knocked down were screened by Western blot analysis and confirmed by RT-PCR. CHO cells with both Bax and Bak knocked down showed a clear resistance against cytotoxic lectins and UV irradiation-induced apoptosis. Compared to original CHO-K1 cells, these cells also survived longer when cultured under extreme conditions such as complete nutrient depletion or in high-osmolality medium. CHO cells with both Bax and Bak genes knocked down displayed an extended lifespan as well as higher viable cell densities in fed-batch cultures, both in adherent form on microcarrier beads and in suspension. The IFN-gamma productivity by a rCHO IFN-gamma cell line in which both Bak and Bax were knocked down increased by 35% compared to the control cells. These results indicate that the genetic inactivation of Bax and Bak in recombinant CHO cells can be an effective strategy in delaying the onset of apoptosis in batch and fed-batch cultures.
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Affiliation(s)
- Sing Fee Lim
- Bioprocessing Technology Institute, Agency for Science, Technology and Research, 20 Biopolis Way, 06-01 Centros, Singapore 138668, Singapore
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Sobczuk TM, Camacho FG, Grima EM, Chisti Y. Effects of agitation on the microalgae Phaeodactylum tricornutum and Porphyridium cruentum. Bioprocess Biosyst Eng 2005; 28:243-50. [PMID: 16247611 DOI: 10.1007/s00449-005-0030-3] [Citation(s) in RCA: 109] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2005] [Accepted: 09/12/2005] [Indexed: 11/25/2022]
Abstract
The effect of mechanical agitation on the microalgae Phaeodactylum tricornutum and Porphyridium cruentum was investigated in aerated continuous cultures with and without the added shear protectant Pluronic F68. Damage to cells was quantified through a decrease in the steady state concentration of the biomass in the photobioreactor. For a given aeration rate, the steady state biomass concentration rose with increasing rate of mechanical agitation until an upper limit on agitation speed was reached. This maximum tolerable agitation speed depended on the microalgal species. Further increase in agitation speed caused a decline in the steady state concentration of the biomass. An impeller tip speed of >1.56 m s(-1) damaged P. tricornutum in aerated culture. In contrast, the damage threshold tip speed for P. cruentum was between 2.45 and 2.89 m s(-1). Mechanical agitation was not the direct cause of cell damage. Damage occurred because of the rupture of small gas bubbles at the surface of the culture, but mechanical agitation was instrumental in generating the bubbles that ultimately damaged the cells. Pluronic F68 protected the cells against damage and increased the steady state concentration of the biomass relative to operation without the additive. The protective effect of Pluronic was concentration-dependent over the concentration range of 0.01-0.10% w/v.
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Affiliation(s)
- T Mazzuca Sobczuk
- Department of Chemical Engineering, University of Almería, 04071, Almería, Spain
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Barbosa MJ, Albrecht M, Wijffels RH. Hydrodynamic stress and lethal events in sparged microalgae cultures. Biotechnol Bioeng 2003; 83:112-20. [PMID: 12740938 DOI: 10.1002/bit.10657] [Citation(s) in RCA: 100] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The effect of high superficial gas velocities in continuous and batch cultures of the strains Dunaliella tertiolecta, Chlamydomonas reinhardtii wild-type and cell wall-lacking mutant was studied in bubble columns. No cell damage was found for D. tertiolecta and C. reinhardtii (wild-type) up to superficial gas velocities of 0.076 and 0.085 m s(-1), respectively, suggesting that high superficial gas velocities alone cannot be responsible for cell death and, consequently, bubble bursting cannot be the sole cause for cell injury. A death rate of 0.46 +/- 0.08 h(-1) was found for C. reinhardtii (cell wall-lacking mutant) at a superficial gas velocity of 0.076 m s(-1), and increased to 1.01 +/- 0.29 h(-1) on increasing superficial gas velocity to 0.085 m s(-1). Shear sensitivity is thus strain-dependent and to some extent the cell wall plays a role in the protection against hydrodynamic shear. When studying the effect of bubble formation at the sparger in batch cultures of D. tertiolecta by varying the number of nozzles, a death rate of 0.047 +/- 0.016 h(-1) was obtained at high gas entrance velocities. D. tertiolecta was cultivated in a pilot-plant reactor under different superficial gas velocities of up to 0.026 m s(-1), with relatively low gas entrance velocities and no cell damage was observed. There is some indication that the main parameter causing cell death and damage was the gas entrance velocity at the sparger.
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Affiliation(s)
- Maria J Barbosa
- Food and Bioprocess Engineering Group, Wageningen University, P.O. Box 8129, 6700 EV Wageningen, The Netherlands.
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