Expression Platforms

HCP Antigens and Antibodies from Different CHO Cell Lines

Cell lines derived from Chinese hamster ovary (CHO) cells are widely used in therapeutic protein production because they can perform human-compatible posttranslational modifications, they are easy to use for manufacturing, and they do not propagate most human pathogenic viruses (1, 2). Expressed therapeutic proteins are secreted into CHO culture supernatant along with impurities originating from the host cells themselves. Such host cell proteins (HCPs) are important contaminants for monitoring because they directly affect drug quality, safety, and efficacy. HCPs are…

Simplification of Fed-Batch Processes with a Single-Feed Strategy

Chinese hamster ovary (CHO) cells commonly are used to produce recombinant proteins such as monoclonal antibodies (MAbs) for research, diagnostic, and therapeutic purposes. Culture processes typically rely on a fed-batch approach in which a basal medium enables initial cell growth. Concentrated feeds are used to prevent nutrient depletion, thereby extending culture duration and improving cell growth, viability, and protein titer. A neutral pH feed is desirable because culture pH should remain stable after feedings. The extremely low solubility of l-tyrosine…

Rapid Development of High-Quality, Robust Mammalian Cell Culture Manufacturing Processes

With increasing industry emphasis on providing both rapid and robust processes, companies are reaping the benefits of new tools for risk management and process analytical controls. As a current example of these approaches, Fujifilm Diosynth scientists have accelerated the development process from gene to finish by shortening the timeline, incorporating quality by design (QbD) principles, and designing the process to be as robust as possible. When the Apollo mammalian expression cell line was introduced three years ago, the time from…

Fucosylation of a Therapeutic Antibody: Effects on Antibody-Dependent, Cell-Mediated Cytotoxicity (ADCC) Potency and Efficacy

Product quality attributes are critical for the functionality and manufacturability of therapeutic antibodies. They can be significantly influenced by a number of production process parameters, such as cell culture media. The composition of growth and feed media can influence antibody glycosylation, including the concentration of ammonia, glutamine, glucose, and metal ions (1, 2). Thus, it is critical during media development and optimization to monitor and consider a culture medium’s impact on glycosylation. For therapeutic antibodies whose mechanism of action includes…

A Single-Use Process for Production of Recombinant Human Follicle-Stimulating Hormone

Follicle-stimulating hormone (FSH) is a heterodimeric glycoprotein consisting of noncovalently linked α and β subunits. It stimulates the growth of immature follicles in ovaries and primary spermatocytes in testes and thus plays an important role in human reproduction (1). Human menopausal gonadotropin for infertility treatment was first introduced into clinical practice in 1950 (2, 3). Subsequently, treatments with urinary FSH have been replaced by recombinant human FSH (rh-FSH), which has been shown to provide several advantages such as absence of…

Development, Qualification, and Application of a Bioreactor Scale-Down Process: Modeling Large-Scale Microcarrier Perfusion Cell Culture

Qualified scale-down models of large-scale cell culture processes are essential to conducting studies for applications such as investigating manufacturing deviations, enhancing process understanding, and improving process robustness. For example, scale-down models can be used for raw material investigations as well as evaluation and qualification of new good manufacturing practice (GMP) cell banks for manufacturing implementation. Process characterization studies are performed also with qualified scale-down models to improve process consistency (1, 2). Often it is impractical to conduct investigational studies at…

Heading for a CHO Revolution: The Need for Cell Line Engineering to Improve Manufacturing Cell Lines

The first recombinant protein licensed for use by the United States Food and Drug Administration (US FDA) was human insulin in 1982 (1). That approval was followed in 1987 by the development of tissue plasminogen activator (tPA), the first complex glycosylated protein generated in mammalian cells to be licensed for therapeutic use. Since then, this area of biology has rapidly expanded in clinics: The FDA approved an average of 15 new biological entities every year between 2006 and 2011 (2).…

30 Years of Upstream Productivity Improvements

We recently completed an analysis of the past 30 years of industry progress in commercial-scale expression titers and bioprocessing yields. These basic measures of biopharmaceutical manufacturing efficiency also benchmark the technological progress made in bioprocessing over recent decades. Titer and yield improvements generally indicate related bioprocessing cost savings, something most commercial-scale manufacturers work to improve. This focus on efficiency and productivity has led to constant bioprocessing improvements even for long-approved and -marketed products. Our findings indicate that although upstream titers…

Ask the Expert – Optimizing Cell Culture Media Supplements: Using Design of Experiments for CHO and HEK293 Cells

with Francesc Gòdia (chemical engineering professor at the Universitat Autònoma de Barcelona) Chemically defined media free of animal-derived components are required for bioprocess operations based on mammalian cells. Supplementation of commercial media with specific compounds was studied using a design of experiments (DoE) approach to screen the most efficient compounds for two cell lines and then determine their optimal conditions. DoE allowed simultaneous testing of several compounds to determine potential interactions among them in addition to their individual effects. Gòdia’s…

A Novel Solid-Media E. coli Platform: Comparison with Standard Fermentation Processes

MicroProtein Technologies Inc. has developed the MPTxpress high-yield, low‑cost, recombinant Escherichia coli manufacturing platform. Rather than using liquid culture media within stirred bioreactors, the system uses trays filled with semisolid (gelled) culture media overlaid with or without a permeable membrane on which the E. coli is cultured. Compared with conventional liquid fermentation platforms, the MPTxpress system reduces the number of steps in up- and downstream processing and required infrastructure, significantly improves yields, and lowers costs. It provides simplicity for mixing…