Bioprocess

About: Bioprocess is a research topic. Over the lifetime, 2219 publications have been published within this topic receiving 50972 citations.

ambr™ Mini-bioreactor as a high-throughput tool for culture process development to accelerate transfer to stainless steel manufacturing scale: comparability study from process performance to product quality attributes

Abstract: Background Enhancing throughput of bioprocess development has become increasingly important to rapidly screen and optimize cell culture process parameters. With increasing timeline pressures to get therapeutic candidates into the clinic, resource intensive approaches such as the use of shake flasks and bench-top bioreactors may limit the design space for experimentation to yield highly productive processes. The need to conduct large numbers of experiments has resulted in the use of miniaturized high-throughput (HT) technology for bioprocess development. One such high-throughput system is the ambrTM platform, a robotically driven, mini-bioreactor system developed by TAP-Sartorius. In this study we assessed and compared the performance parameters of ambrTM mini-bioreactor runs to 2L glasses , 80L and 400L stainless steel bioreactors using a CHO cell line producing a recombinant monoclonal antibody. The daily parameters monitored during the cultures were cell growth and cell viability, offline pH and dissolved oxygen, metabolite profiles (glucose, lactate and ammonia) and monoclonal antibody titer. In addition, we compared the product quality attributes (high and low molecular weight species, charge variants) of the clarified cell culture fluid post Protein-A elution generated in the mini-bioreactor run to the larger manufacturing scales. Materials and methods A genetically engineered Dihydrofolate Reductase (DHFR)-/ DG44 Chinese Hamster Ovary (CHO) cell line with Methotrexate (MTX) as a selective agent, expressing a recombinant monoclonal antibody was used. Cells were cultivated for 14 days in a fed-batch mode in a chemically defined medium and fed according to process description. Culture systems: Different bioreactor scales were used in this study : ambrTM48 (TAP -Sartorius Biosystems), an automated system with 48 disposable microbioreactor vessels, 2L stirred tank glasses bioreactors with Biostat B-DCUII control systems (Sartorius Stedim), 80L and 400L stainless-steel bioreactors (Zeta). Data was analysed using JMP statistical (SAS) program. All the experiments were conducted using the same cell bank at the same cell age at bioreactor inoculation. pH (7.0 +/0.2) was controlled using CO2 and base addition. The scale independent factors (pH, DO set point, seeding density, temperature, culture duration, media and feed composition), were the same for all the scales. The scale dependent factors (culture start volume, feed volumes) were linearly adapted. Agitation speed and aeration that were determined theoretically or though experiment. Sampling plans and sample volumes were especially adapted to the ambrTM system to take into account the low bioreactor volume. * Correspondence: frederic.delouvroy@ucb.com Upstream Process Sciences, Biotech Sciences, UCB Pharma S.A., Chemin du Foriest, Braine l’Alleud, Belgium Delouvroy et al. BMC Proceedings 2015, 9(Suppl 9):P78 http://www.biomedcentral.com/1753-6561/9/S9/P78

Combinatorial impact of Sec signal peptides from Bacillus subtilis and bioprocess conditions on heterologous cutinase secretion by Corynebacterium glutamicum

Abstract: The impact of Sec signal peptides (SPs) from Bacillus subtilis in combination with isopropyl-β- d-1-thiogalactopyranoside concentration and feeding profile was investigated for heterologous protein secretion performance by Corynebacterium glutamicum using cutinase as model enzyme. Based on a comprehensive data set of about 150 bench-scale bioreactor cultivations in fed-batch mode and choosing the cutinase yield as objective, it was shown that relative secretion performance for bioprocesses remains very similar, irrespective of the applied SP enabling Sec-mediated cutinase secretion. However, to achieve the maximal absolute cutinase yield, careful adjustment of bioprocess conditions was found to be necessary. A model-based, two-step multiple regression approach resembled the collected data in a comprehensive way. The corresponding results suggest that the choice of the heterologous Sec SP and its interaction with the adjusted exponential feeding profile is highly relevant to maximize absolute cutinase yield in this study. For example, the impact of Sec SP is high at low growth rates and low at high growth rates. However, promising Sec SPs could be inferred from less complex batch cultivations. The extensive data were also evaluated in terms of cutinase productivity, highlighting the well-known trade-off between yield and productivity in bioprocess development in detail. Conclusively, only the right combination of target protein, Sec SP, and bioprocess conditions is the key to success.

Microcarrier Culture Systems for Stem Cell Manufacturing

Abstract: Stem cells hold a great promise for the generation of new cell therapies for many currently untreatable diseases, for human disease modeling or drug discovery. Many of these applications, however, will require the production of very large numbers of cells. A versatile system for the large-scale production of stem cells under adherent conditions is provided by microcarrier culture technology, which has been originally developed for animal cell culture in suspension bioreactors. This chapter describes the main characteristics of stem cell culture on microcarriers, providing an overview of the different bioprocess development steps. General guidelines and methodologies for the selection of the most appropriate microcarrier and its adaptation for the different stem cell types are provided as well as strategies for cell inoculation, bioreactor operation, and efficient cell harvesting and downstream processing.

Hydrodynamics and bioprocess considerations in designing bioreactors for cardiac tissue engineering

Abstract: One of the most attractive fields in regenerative medicine and tissue engineering is cardiac cell regeneration due to the limited capacity of the heart muscle to regenerate itself. Recent advances in the field of stem cell bioprocess technology and biomaterials have accelerated progress in creating three-dimensional (3D) cardiac engineered tissues in vitro. Control of bulk and microscopic transport efficiency, which is determined by the choice of the bioreactor design and substrate material, poses direct influence on cell viability, proliferation and differentiation in vitro. This paper provides a critical review on the hydrodynamic considerations with respect to design aspects of the bioreactor and selection of substrate material for 3D cardiac tissue engineering.