Innovative technologies and trends in cell line development
Biologics are one of the most successful classes of medicines today. In 2019, among 20 top selling medicines 10 were biologics. The top 10 best selling biologics generated the revenue $70,469.0 in 2019. Humira is one of the top-selling biologics ($19,169.0 in 2019). Biotherapeutics such as monoclonal antibodies, peptides, recombinant proteins, vaccines, blood-related products are developed and produced using genetically modified cell lines. Cell lines are one of the major tools used in research for studying the normal physiology, & biochemistry of cells, the effects of drugs & toxic compounds on the cells, drug screening, development & large scale manufacturing of biological compounds. In biomedical research, cell lines have a variety of applications including measuring the effects of radiation, drugs, chemicals, toxins, and viruses, and in the development of vaccines and pharmaceuticals. Cell lines are also used in virology laboratories for studies and cultivation of pathogenic viruses such as polio, measles, and emerging novel virus strains, and cancer research and drug discovery. The therapeutic proteins such as monoclonal antibodies, recombinant proteins are mostly produced by microorganisms (microbial systems) and mammalian cells (mammalian expression systems), and in rare cases by insect cells and plant cells. Mammalian expression systems are generally the preferred platform for manufacturing biopharmaceuticals, as these cell lines are able to produce large, complex proteins with post-translational modifications (PTMs; most notably glycosylation) similar to those produced in humans. CHO cells have been used most widely for the commercial production of therapeutic proteins.
The increasing demand of biologics or biosimilars owes a great deal to technological advancement in expression vector design, cell line engineering and clone screening to generate a stable and consistently expressing monoclonal cell line for the production high quantity and desired quality recombinant proteins through an efficient and cost-effective manufacturing process. The cell line development service global market generated revenue of $710.6 million in 2020 and is expected to grow at a CAGR of 11.5% to reach $1,702.2 million by 2028.
Creation of stable productive cell lines relies on three pillars: the cell line, the vector and the screening process. Host cell engineering represents a powerful approach to enhance production cell performance for biopharmaceutical manufacturing. The appropriate cell line selected is engineered to include features of better growth, no cell aggregation, more efficient metabolism like reduced lactate production, increased tolerance to cultural changes and nutritional changes. Some of the advances in cell line generation include new expression vectors and transfection technology to introduce the genes into cells, advanced screening technologies and targeted gene engineering of the cell lines. Directed integration of transgene at a specific genomic location reduced variability in the production of clones. The Cre-loxP system and the FLP/FRT system are some of the site-specific recombinases used for targeted transgene integration. Site-specific recombination allows stable cell clones with high productivity to be generated in a more controllable and predictable manner and is likely to significantly reduce the time required for cell line screening.
Successful integration of recombinant genes into areas in the chromatin where transcription is not silenced is one of the major challenges in recombinant protein expression. The discovery of regulatory genetic elements, such as ubiquitous chromatin opening elements (UCOEs) and Scaffold or Matrix Attachment Regions (S/MARs) completely revolutionized the field of cell line development. Furthermore, the recent transfer of the novel genome editing tools (CRISPR/Cas9, zinc finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs), and recombinase-mediated cassette exchange (RMCE) into the cell research area has paved the way for establishing cell lines showing multiple knockout phenotypes. The knockout/knockdown phenotypes are meaningful approaches to improve the PTMs of biopharmaceuticals in different production platforms. In addition, high-throughput omics contribute to a better understanding of the genes responsible for certain cellular phenotypes. Omics characterization of the cell lines allows for targeted engineering approaches to further enhance therapeutic antibody production. Companies are constantly focused on the development of these novel technologies for high levels of recombinant protein expression. For instance, in April 2019, Lonza launched GS piggyBac – a highly efficient gene integration technology and offers benefits for bioprocessing, particularly for challenging low-expressing proteins, helping to generate high-performing pools for material supply.
Screening of high producing cell clone is one of the important step in cell line development. Automated screening technologies helps to screen a large number of clones to identify the small subset of high producers. Nanofluidic technologies offer a promising solution to further miniaturize cell culture processes. One such technology platform has been developed by Berkeley Lights i.e optofluidic platform (single-cell screening and analysis technology) which significantly shortened the time required to identify and select the optimal cell line manufacturing clones within the CLD process. For instance, in November 2019, Samsung Biologics adopts Beacon optofluidic platform for cell line development from Berkeley Lights. In August 2020, Samsung Biologics launched, new proprietary CHO-based cell line technology, S-CHOice technology combination with Berkeley Lights’ Beacon technology, will emerge as the company’s excellent platform for cell line development.
The innovative technologies improved all aspects in cell line development, allowing for higher productivity levels and expression of proteins previously not eligible for manufacturing such as complex, non-natural or difficult-to-express proteins and paved the pathway for the development and production of novel therapeutics. Most of CDO or CDMO are developing advanced cell line development platforms to generate high-performance, highly stable, production cell lines. These advanced platforms will attract pharma or biotech companies to outsource cell line development, for the development and production of novel therapeutics. For instance, in the middle of a COVID -19 pandemic, there is heightened importance placed on the development of therapeutic modalities such as vaccines, nucleic acids, small molecules, convalescent serum, IgG and mAbs. In June 2020, Spicona, Inc. has signed an agreement with Catalent to develop virus-like protein (VLP)-based vaccine against COVID-19. Under this agreement, Catalent will use its proprietary GPEx cell line development technology to develop a cell line expressing the recombinant VLP.
The major players in the cell line development service market are Abzena PLC (U.K.), AGC Inc. (AGC Biologics) (Japan), Albany Molecular Research Inc. (AMRI) (U.S.), Boehringer Ingelheim International GmbH (Germany), Catalent Inc. (U.S.), Charles River Laboratories International Inc. (U.S.), Fujifilm Holdings Corporation (Fujifilm Diosynth Biotechnologies) (Japan), Genscript Biotech Corporation (China), JSR Corporation [JSR Life Sciences, LLC (KBI biopharma, Selexis SA, CrownBio)] (Japan), Lonza Group Ltd. (Switzerland), Rentschler Biopharma SE (Germany), Samsung Biologics Co. Ltd. (South Korea), Thermofischer Scientific Inc. (Patheon N.V.) (Brammer Bio) (U.S.), Wuxi Biologics (Cayman) Inc. (China), Sartious Group (Cellca, Bio Outsource) (Germany), Eurofins Scientific S.E (DiscoverX, GATC Biotech AG, Eurofins CDMO, Advinus) (Luxembourg).