1
|
Sripada SA, Hosseini M, Ramesh S, Wang J, Ritola K, Menegatti S, Daniele MA. Advances and opportunities in process analytical technologies for viral vector manufacturing. Biotechnol Adv 2024; 74:108391. [PMID: 38848795 DOI: 10.1016/j.biotechadv.2024.108391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 03/14/2024] [Accepted: 05/29/2024] [Indexed: 06/09/2024]
Abstract
Viral vectors are an emerging, exciting class of biologics whose application in vaccines, oncology, and gene therapy has grown exponentially in recent years. Following first regulatory approval, this class of therapeutics has been vigorously pursued to treat monogenic disorders including orphan diseases, entering hundreds of new products into pipelines. Viral vector manufacturing supporting clinical efforts has spurred the introduction of a broad swath of analytical techniques dedicated to assessing the diverse and evolving panel of Critical Quality Attributes (CQAs) of these products. Herein, we provide an overview of the current state of analytics enabling measurement of CQAs such as capsid and vector identities, product titer, transduction efficiency, impurity clearance etc. We highlight orthogonal methods and discuss the advantages and limitations of these techniques while evaluating their adaptation as process analytical technologies. Finally, we identify gaps and propose opportunities in enabling existing technologies for real-time monitoring from hardware, software, and data analysis viewpoints for technology development within viral vector biomanufacturing.
Collapse
Affiliation(s)
- Sobhana A Sripada
- Department of Chemical and Biomolecular Engineering, North Carolina State University, 911 Partners Way, Raleigh, NC, 27695, USA
| | - Mahshid Hosseini
- Joint Department of Biomedical Engineering, North Carolina State University, and University of North Carolina, Chapel Hill, 911 Oval Dr., Raleigh, NC 27695, USA
| | - Srivatsan Ramesh
- Department of Chemical and Biomolecular Engineering, North Carolina State University, 911 Partners Way, Raleigh, NC, 27695, USA
| | - Junhyeong Wang
- Joint Department of Biomedical Engineering, North Carolina State University, and University of North Carolina, Chapel Hill, 911 Oval Dr., Raleigh, NC 27695, USA
| | - Kimberly Ritola
- North Carolina Viral Vector Initiative in Research and Learning (NC-VVIRAL), North Carolina State University, 890 Oval Dr, Raleigh, NC 27695, USA; Neuroscience Center, Brain Initiative Neurotools Vector Core, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Stefano Menegatti
- Department of Chemical and Biomolecular Engineering, North Carolina State University, 911 Partners Way, Raleigh, NC, 27695, USA; North Carolina Viral Vector Initiative in Research and Learning (NC-VVIRAL), North Carolina State University, 890 Oval Dr, Raleigh, NC 27695, USA; Biomanufacturing Training and Education Center, North Carolina State University, 890 Main Campus Dr, Raleigh, NC 27695, USA.
| | - Michael A Daniele
- Joint Department of Biomedical Engineering, North Carolina State University, and University of North Carolina, Chapel Hill, 911 Oval Dr., Raleigh, NC 27695, USA; North Carolina Viral Vector Initiative in Research and Learning (NC-VVIRAL), North Carolina State University, 890 Oval Dr, Raleigh, NC 27695, USA; Department of Electrical and Computer Engineering, North Carolina State University, 890 Oval Dr, Raleigh, NC 27695, USA.
| |
Collapse
|
2
|
Schimek A, Ng JK, Basbas I, Martin F, Xin D, Saleh D, Hubbuch J. An HPLC-SEC-based rapid quantification method for vesicular stomatitis virus particles to facilitate process development. Mol Ther Methods Clin Dev 2024; 32:101252. [PMID: 38774583 PMCID: PMC11107205 DOI: 10.1016/j.omtm.2024.101252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Accepted: 04/18/2024] [Indexed: 05/24/2024]
Abstract
Virus particle (VP) quantification plays a pivotal role in the development of production processes of VPs for virus-based therapies. The yield based on total VP count serves as a process performance indicator for evaluating process efficiency and consistency. Here, a label-free particle quantification method for enveloped VPs was developed, with potential applications in oncolytic virotherapy, vaccine development, and gene therapy. The method comprises size-exclusion chromatography (SEC) separation using high-performance liquid chromatography (HPLC) instruments. Ultraviolet (UV) was used for particle quantification and multi-angle light scattering (MALS) for particle characterization. Consistent recoveries of over 97% in the SEC were achieved upon mobile phase screenings and addition of bovine serum albumin (BSA) as sample stabilizer. A calibration curve was generated, and the method's performance and applicability to in-process samples were characterized. The assay's repeatability variation was <1% and its intermediate precision variation was <3%. The linear range of the method spans from 7.08 × 108 to 1.72 × 1011 VP/mL, with a limit of detection (LOD) of 7.72 × 107 VP/mL and a lower limit of quantification (LLOQ) of 4.20 × 108 VP/mL. The method, characterized by its high precision, requires minimal hands-on time and provides same-day results, making it efficient for process development.
Collapse
Affiliation(s)
- Adrian Schimek
- ViraTherapeutics GmbH, Bundesstraße 27, 6063 Rum, Austria
| | - Judy K.M. Ng
- ViraTherapeutics GmbH, Bundesstraße 27, 6063 Rum, Austria
| | - Ioannes Basbas
- ViraTherapeutics GmbH, Bundesstraße 27, 6063 Rum, Austria
| | - Fabian Martin
- ViraTherapeutics GmbH, Bundesstraße 27, 6063 Rum, Austria
| | - Dongyue Xin
- Boehringer Ingelheim Pharmaceuticals Inc, 900 Ridgebury Road, Ridgefield, CT 06877, USA
| | - David Saleh
- Boehringer Ingelheim Pharma GmbH & Co. KG, Birkendorfer Str. 65, 88397 Biberach, Germany
| | - Jürgen Hubbuch
- Karlsruhe Institute of Technology, Institute of Process Engineering in Life Sciences, Section IV Biomolecular Separation Engineering, Fritz-Haber-Weg 2, 76131 Karlsruhe, Germany
| |
Collapse
|
3
|
Vaz TA, Rodrigues AF, Coroadinha AS. Exploring nutrient supplementation and bioprocess optimization to improve the production of lentiviral vectors in serum-free medium suspension cultures. Biotechnol J 2024; 19:e2300212. [PMID: 37903159 DOI: 10.1002/biot.202300212] [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: 05/11/2023] [Revised: 10/20/2023] [Accepted: 10/25/2023] [Indexed: 11/01/2023]
Abstract
The use of lentiviral vectors (LV) in gene therapy has been growing in recent years. To meet the increasing clinical demand, LV production platforms will benefit from improved productivity and scalability to enable cost-effective manufacture of LV-based therapies. Here we report the adaptation of 293T cells to serum-free suspension cultures and the improvement of LV yields through transfection parameters optimization, process intensification and medium supplementation with nutrient boosters. Cells were sequentially adapted to different serum-free culture media, transfection parameters were optimized and the two best-performing conditions were selected to explore process intensification by increasing cell density at the time of transfection. LV production at higher cell densities increased volumetric titers up to 12-fold and lipid supplementation was the most efficient metabolic optimization strategy further enhancing LV productivity by 3-fold. Furthermore, cell concentration was identified and validated as an important source of transfection variability impairing cellular uptake of DNA polyplexes, impacting transfection efficiency and reducing LV titers down to 6-fold. This work contributes to improving LV-based gene therapy by establishing new scalable manufacturing platforms and providing key metabolic insights, unveiling important bioreaction parameters to improve vector yields.
Collapse
Affiliation(s)
- Tiago A Vaz
- iBET, Instituto de Biologia Experimental e Tecnológica, Oeiras, Portugal
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Ana F Rodrigues
- iBET, Instituto de Biologia Experimental e Tecnológica, Oeiras, Portugal
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
- LASIGE, Faculdade de Ciências da Universidade de Lisboa, Lisboa, Portugal
| | - Ana S Coroadinha
- iBET, Instituto de Biologia Experimental e Tecnológica, Oeiras, Portugal
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| |
Collapse
|
4
|
Kilgore R, Minzoni A, Shastry S, Smith W, Barbieri E, Wu Y, LeBarre JP, Chu W, O'Brien J, Menegatti S. The downstream bioprocess toolbox for therapeutic viral vectors. J Chromatogr A 2023; 1709:464337. [PMID: 37722177 DOI: 10.1016/j.chroma.2023.464337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 08/24/2023] [Accepted: 08/27/2023] [Indexed: 09/20/2023]
Abstract
Viral vectors are poised to acquire a prominent position in modern medicine and biotechnology owing to their role as delivery agents for gene therapies, oncolytic agents, vaccine platforms, and a gateway to engineer cell therapies as well as plants and animals for sustainable agriculture. The success of viral vectors will critically depend on the availability of flexible and affordable biomanufacturing strategies that can meet the growing demand by clinics and biotech companies worldwide. In this context, a key role will be played by downstream process technology: while initially adapted from protein purification media, the purification toolbox for viral vectors is currently undergoing a rapid expansion to fit the unique biomolecular characteristics of these products. Innovation efforts are articulated on two fronts, namely (i) the discovery of affinity ligands that target adeno-associated virus, lentivirus, adenovirus, etc.; (ii) the development of adsorbents with innovative morphologies, such as membranes and 3D printed monoliths, that fit the size of viral vectors. Complementing these efforts are the design of novel process layouts that capitalize on novel ligands and adsorbents to ensure high yield and purity of the product while safeguarding its therapeutic efficacy and safety; and a growing panel of analytical methods that monitor the complex array of critical quality attributes of viral vectors and correlate them to the purification strategies. To help explore this complex and evolving environment, this study presents a comprehensive overview of the downstream bioprocess toolbox for viral vectors established in the last decade, and discusses present efforts and future directions contributing to the success of this promising class of biological medicines.
Collapse
Affiliation(s)
- Ryan Kilgore
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695, United States.
| | - Arianna Minzoni
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695, United States
| | - Shriarjun Shastry
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695, United States; Biomanufacturing Training and Education Center (BTEC), North Carolina State University, Raleigh, NC 27695, United States
| | - Will Smith
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695, United States
| | - Eduardo Barbieri
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695, United States
| | - Yuxuan Wu
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695, United States
| | - Jacob P LeBarre
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695, United States
| | - Wenning Chu
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695, United States
| | - Juliana O'Brien
- Department of Chemistry, North Carolina State University, Raleigh, NC 27695, United States
| | - Stefano Menegatti
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695, United States; Biomanufacturing Training and Education Center (BTEC), North Carolina State University, Raleigh, NC 27695, United States; North Carolina Viral Vector Initiative in Research and Learning, North Carolina State University, Raleigh, NC 27695, United States
| |
Collapse
|
5
|
He Z, Kwee EJ, Cleveland MH, Cole KD, Lin-Gibson S, He HJ. Quantitation and integrity evaluation of RNA genome in lentiviral vectors by direct reverse transcription-droplet digital PCR (direct RT-ddPCR). Sci Rep 2023; 13:14470. [PMID: 37660227 PMCID: PMC10475045 DOI: 10.1038/s41598-023-41644-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: 06/05/2023] [Accepted: 08/29/2023] [Indexed: 09/04/2023] Open
Abstract
Lentiviral vectors (LV) have proven to be powerful tools for stable gene delivery in both dividing and non-dividing cells. Approval of these LVs for use in clinical applications has been achieved by improvements in LV design. Critically important characteristics concerning quality control are LV titer quantification and the detection of impurities. However, increasing evidence concerning high variability in titration assays indicates poor harmonization of the methods undertaken to date. In this study, we developed a direct reverse transcription droplet digital PCR (Direct RT-ddPCR) approach without RNA extraction and purification for estimation of LV titer and RNA genome integrity. The RNA genome integrity was assessed by RT-ddPCR assays targeted to four distant regions of the LV genome. Results of the analyses showed that direct RT-ddPCR without RNA extraction and purification performs similarly to RT-ddPCR on purified RNA from 3 different LV samples, in terms of robustness and assay variance. Interestingly, these RNA titer results were comparable to physical titers by p24 antigen ELISA (enzyme-linked immunosorbent assay). Moreover, we confirmed the partial degradation or the incomplete RNA genomes in the prepared 3 LV samples. These results may partially explain the discrepancy of the LV particle titers to functional titers. This work not only demonstrates the feasibility of direct RT-ddPCR in determining LV titers, but also provides a method that can be easily adapted for RNA integrity assessment.
Collapse
Affiliation(s)
- Zhiyong He
- Material Measurement Laboratory, National Institute of Standards and Technology, 100 Bureau Drive, MS 8312, Gaithersburg, MD, 20899, USA.
| | - Edward J Kwee
- Material Measurement Laboratory, National Institute of Standards and Technology, 100 Bureau Drive, MS 8312, Gaithersburg, MD, 20899, USA
| | - Megan H Cleveland
- Material Measurement Laboratory, National Institute of Standards and Technology, 100 Bureau Drive, MS 8312, Gaithersburg, MD, 20899, USA
| | - Kenneth D Cole
- Material Measurement Laboratory, National Institute of Standards and Technology, 100 Bureau Drive, MS 8312, Gaithersburg, MD, 20899, USA
| | - Sheng Lin-Gibson
- Material Measurement Laboratory, National Institute of Standards and Technology, 100 Bureau Drive, MS 8312, Gaithersburg, MD, 20899, USA
| | - Hua-Jun He
- Material Measurement Laboratory, National Institute of Standards and Technology, 100 Bureau Drive, MS 8312, Gaithersburg, MD, 20899, USA.
| |
Collapse
|
6
|
Tran MY, Kamen AA. Production of Lentiviral Vectors Using a HEK-293 Producer Cell Line and Advanced Perfusion Processing. Front Bioeng Biotechnol 2022; 10:887716. [PMID: 35774066 PMCID: PMC9237754 DOI: 10.3389/fbioe.2022.887716] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 05/24/2022] [Indexed: 12/03/2022] Open
Abstract
The field of lentiviral vector (LV) production continues to face challenges in large-scale manufacturing, specifically regarding producing enough vectors to meet the demand for treating patients as well as producing high and consistent quality of vectors for efficient dosing. Two areas of interest are the use of stable producer cell lines, which facilitates the scalability of LV production processes as well as making the process more reproducible and robust for clinical applications, and the search of a cell retention device scalable to industrial-size bioreactors. This manuscript investigates a stable producer cell line for producing LVs with GFP as the transgene at shake flask scale and demonstrates LV production at 3L bioreactor scale using the Tangential Flow Depth Filtration (TFDF) as a cell retention device in perfusion mode. Cumulative functional yields of 3.3 x 1011 and 3.9 x 1011 transducing units were achieved; the former over 6 days of LV production with 16.3 L of perfused media and the latter over 4 days with 16 L. In comparing to a previously published value that was achieved using the same stable producer cell line and the acoustic filter as the perfusion device at the same bioreactor scale, the TFDF perfusion run produced 1.5-fold higher cumulative functional yield. Given its scale-up potential, the TFDF is an excellent candidate to be further evaluated to determine optimized conditions that can ultimately support continuous manufacturing of LVs at large scale.
Collapse
|
7
|
Li G, Zhang Q, Han Z, Zhu Y, Shen H, Liu Z, Zhou Z, Ding W, Han S, He J, Yin Z, Zhou J, Ou R, Luo M, Liu S. IL-7 and CCR2b Co-Expression-Mediated Enhanced CAR-T Survival and Infiltration in Solid Tumors. Front Oncol 2021; 11:734593. [PMID: 34778046 PMCID: PMC8579717 DOI: 10.3389/fonc.2021.734593] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 10/06/2021] [Indexed: 01/06/2023] Open
Abstract
Chimeric antigen receptor T (CAR-T) cells are not effective in solid tumor treatment due to reduced invasion and expansion, and short survival time. This study aimed to explore whether interleukin (IL)-7 and CCR2b expression could improve GD2-CAR-T cell survival and infiltration in neuroblastoma and melanoma treatment. IL-7 and CCR2b were inserted into the classical second-generation CAR structure to construct 7×2b CAR. The 7×2b CAR-T cell phenotypes were evaluated by flow cytometry and the chemokine levels by ELISA. The 7×2b CAR-T cell migration and anti-tumor abilities were detected by Transwell assay and animal experiments in vivo. We report that compared with that of CAR-T cells, 7×2b CAR-T cell IL-7 secretion and CCR2b expression did not affect the T cell surface expression of CAR or CAR-T specificity and efficacy against tumor cells. The 7×2b CAR-T cells could induce IFN-γ secretion in GD2-positive tumor cells, killing them as well as conventional CAR-T cells. Moreover, IL-7 and CCR2b co-expression enhanced the 7×2b CAR-T cell survival and migration. Similar to conventional CAR-T, 7×2b CAR-T cells could also inhibit tumor growth and increase IFN-γ, Gzms-B, and IL-2 expression. Finally, unlike in mice injected with CAR-T cells, CD3 expression was the most abundant in the spleen and tumor tissues in mice injected with 7×2b CAR-T cells. Our study demonstrates that IL-7 and CCR2b co-expression in GD2-CAR-T cells exhibit stronger anti-tumor activity than classical second-generation CAR-T cells, shedding light on the potential novel GD2-positive neuroblastoma and melanoma treatment approach.
Collapse
Affiliation(s)
- Guangchao Li
- Department of Hematology, Guangdong Second Provincial General Hospital, Guangzhou, China.,Department of Research and Development, Guangzhou Bio-gene Technology Co., Ltd, Guangzhou, China
| | - Qing Zhang
- Department of Hematology, Guangdong Second Provincial General Hospital, Guangzhou, China
| | - Zeping Han
- Department of Laboratory, Central Hospital of Panyu District, Guangzhou, China
| | - Yangmin Zhu
- Department of Hematology, Guangdong Second Provincial General Hospital, Guangzhou, China
| | - Huijuan Shen
- Department of Hematology, Guangdong Second Provincial General Hospital, Guangzhou, China
| | - Zhi Liu
- Department of Hematology, Guangdong Second Provincial General Hospital, Guangzhou, China
| | - Zhao Zhou
- Department of Research and Development, Guangzhou Bio-gene Technology Co., Ltd, Guangzhou, China
| | - Wen Ding
- Department of Research and Development, Guangzhou Bio-gene Technology Co., Ltd, Guangzhou, China
| | - Siqi Han
- Department of Medical Oncology, Jinling Hospital, Nanjing Clinical School of Southern Medical University, Nanjing, China
| | - Jinhua He
- Department of Laboratory, Central Hospital of Panyu District, Guangzhou, China
| | - Zhao Yin
- Department of Hematology, Guangdong Second Provincial General Hospital, Guangzhou, China
| | - Jie Zhou
- Department of Hematology, People's Hospital of Deyang City, Deyang, China
| | - Ruiming Ou
- Department of Hematology, Guangdong Second Provincial General Hospital, Guangzhou, China
| | - Min Luo
- Department of Hematology, Guangdong Second Provincial General Hospital, Guangzhou, China.,Department of Research and Development, Guangzhou Bio-gene Technology Co., Ltd, Guangzhou, China
| | - Shuang Liu
- Department of Hematology, Guangdong Second Provincial General Hospital, Guangzhou, China
| |
Collapse
|
8
|
Do Minh A, Kamen AA. Critical Assessment of Purification and Analytical Technologies for Enveloped Viral Vector and Vaccine Processing and Their Current Limitations in Resolving Co-Expressed Extracellular Vesicles. Vaccines (Basel) 2021; 9:vaccines9080823. [PMID: 34451948 PMCID: PMC8402407 DOI: 10.3390/vaccines9080823] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2021] [Revised: 07/19/2021] [Accepted: 07/20/2021] [Indexed: 12/15/2022] Open
Abstract
Viral vectors and viral vaccines are invaluable tools in prevention and treatment of diseases. Many infectious diseases are controlled using vaccines designed from subunits or whole viral structures, whereas other genetic diseases and cancers are being treated by viruses used as vehicles for delivering genetic material in gene therapy or as therapeutic agents in virotherapy protocols. Viral vectors and vaccines are produced in different platforms, from traditional embryonated chicken eggs to more advanced cell cultures. All these expression systems, like most cells and cellular tissues, are known to spontaneously release extracellular vesicles (EVs). EVs share similar sizes, biophysical characteristics and even biogenesis pathways with enveloped viruses, which are currently used as key ingredients in a number of viral vectors and licensed vaccine products. Herein, we review distinctive features and similarities between EVs and enveloped viruses as we revisit the downstream processing steps and analytical technologies currently implemented to produce and document viral vector and vaccine products. Within a context of well-established viral vector and vaccine safety profiles, this review provides insights on the likely presence of EVs in the final formulation of enveloped virus products and discusses the potential to further resolve and document these components.
Collapse
|
9
|
Characterization of Extracellular Vesicles Secreted in Lentiviral Producing HEK293SF Cell Cultures. Viruses 2021; 13:v13050797. [PMID: 33946875 PMCID: PMC8145507 DOI: 10.3390/v13050797] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2021] [Revised: 04/23/2021] [Accepted: 04/28/2021] [Indexed: 12/15/2022] Open
Abstract
Lentiviral vectors (LVs) are a powerful tool for gene and cell therapy and human embryonic kidney cells (HEK293) have been extensively used as a platform for production of these vectors. Like most cells and cellular tissues, HEK293 cells release extracellular vesicles (EVs). EVs released by cells share similar size, biophysical characteristics and even a biogenesis pathway with cell-produced enveloped viruses, making it a challenge to efficiently separate EVs from LVs. Thus, EVs co-purified with LVs during downstream processing, are considered “impurities” in the context of gene and cell therapy. A greater understanding of EVs co-purifying with LVs is needed to enable improved downstream processing. To that end, EVs from an inducible lentivirus producing cell line were studied under two conditions: non-induced and induced. EVs were identified in both conditions, with their presence confirmed by transmission electron microscopy and Western blot. EV cargos from each condition were then further characterized by a multi-omic approach. Nineteen proteins were identified by mass spectrometry as potential EV markers to differentiate EVs in LV preparations. Lipid composition of EV preparations before and after LV induction showed similar enrichment in phosphatidylserine. RNA cargos in EVs showed enrichment in transcripts involved in viral processes and binding functions. These findings provide insights on the product profile of lentiviral preparations and could support the development of improved separation strategies aimed at removing co-produced EVs.
Collapse
|
10
|
Perry C, Rayat ACME. Lentiviral Vector Bioprocessing. Viruses 2021; 13:268. [PMID: 33572347 PMCID: PMC7916122 DOI: 10.3390/v13020268] [Citation(s) in RCA: 68] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 02/02/2021] [Accepted: 02/03/2021] [Indexed: 12/11/2022] Open
Abstract
Lentiviral vectors (LVs) are potent tools for the delivery of genes of interest into mammalian cells and are now commonly utilised within the growing field of cell and gene therapy for the treatment of monogenic diseases and adoptive therapies such as chimeric antigen T-cell (CAR-T) therapy. This is a comprehensive review of the individual bioprocess operations employed in LV production. We highlight the role of envelope proteins in vector design as well as their impact on the bioprocessing of lentiviral vectors. An overview of the current state of these operations provides opportunities for bioprocess discovery and improvement with emphasis on the considerations for optimal and scalable processing of LV during development and clinical production. Upstream culture for LV generation is described with comparisons on the different transfection methods and various bioreactors for suspension and adherent producer cell cultivation. The purification of LV is examined, evaluating different sequences of downstream process operations for both small- and large-scale production requirements. For scalable operations, a key focus is the development in chromatographic purification in addition to an in-depth examination of the application of tangential flow filtration. A summary of vector quantification and characterisation assays is also presented. Finally, the assessment of the whole bioprocess for LV production is discussed to benefit from the broader understanding of potential interactions of the different process options. This review is aimed to assist in the achievement of high quality, high concentration lentiviral vectors from robust and scalable processes.
Collapse
Affiliation(s)
- Christopher Perry
- The Advanced Centre for Biochemical Engineering, Department of Biochemical Engineering, University College London, Gower St, London WC1E 6BT, UK;
- Division of Advanced Therapies, National Institute for Biological Standards and Control, South Mimms EN6 3QG, UK
| | - Andrea C. M. E. Rayat
- The Advanced Centre for Biochemical Engineering, Department of Biochemical Engineering, University College London, Gower St, London WC1E 6BT, UK;
| |
Collapse
|