Online prediction of product titer and solubility of recombinant proteins in Escherichia coli fed‐batch cultivations

Abstract

BACKGROUND A goal in the production of biopharmaceuticals is to replace the cost‐intensive, empirical ‘quality by testing’ approach with rational, knowledge‐based ‘quality by design’ concepts. The major challenges in this context are the complexity of bioprocesses and the limited online access to process variables related to product quality. The implementation of advanced monitoring strategies combined with chemometric‐based approaches represents a strategy to overcome this bottleneck. RESULTS A series of recombinant E. coli fed‐batch production processes was conducted to provide an accurate data set for development of predictive statistical models. The applicability of partial least squares regression and radial basis function artificial neural network‐based models to predict gene dosage, product titer, and solubility of the target protein was evaluated. In addition to signals from standard online measurements, multi‐wavelength fluorescence signals turned out to provide essential information for prediction of product titer and quality. CONCLUSIONS The application of advanced process monitoring concepts comprising recently established analytical targets and statistical modeling allows for real‐time prediction of product related not directly accessible process variables. Availability of such process information facilitates design of advanced process‐control strategies and will strongly support the implementation of quality by design in biopharmaceutical production. © 2014 Society of Chemical Industry

Exploring the capabilities of fluorometric online monitoring on chinese hamster ovary cell cultivations producing a monoclonal antibody

“…Fluorometric soft sensor applications are widely described in literature for the online monitoring of various yeast and bacterial batch fermentations as well as for fed‐batch fermentations using Escherichia coli strains and Saccharomyces cerevisiae . Teixeira et al () proved already that the method is also highly sensitive when used in mammalian cell cultivations with nonfluorescent feed media .…”

“…Fluorescent components that are involved in cell growth and metabolism change characteristically in the course of cultivation. The overall fluorescence signal of the cell culture is a mixture of fluorescence signals, which originate from components such as aromatic amino acids, ATP, NADH, FAD, and vitamins (riboflavin and pyridoxine) . Furthermore, some fluorophores are also supplemented to the culture with the feed medium.…”

Prediction of the Quantity and Purity of an Antibody Capture Process in Real Time

“…While in upstream processing many different online monitoring systems have been developed in the past few years, fewer approaches have been published for monitoring in the downstream processing (DSP) of biopharmaceuticals. This might be due to measurement time constraints.…”

“…Besides that, also in process development and scale-up, online monitoring systems can help to speed up the procedure. [5][6][7] While in upstream processing many different online monitoring systems have been developed in the past few years, [8][9][10][11] fewer approaches have been published for monitoring in the downstream processing (DSP) of biopharmaceuticals. This might be due to measurement time constraints.…”

Process Analytical Technologies in Biopharmaceutical Process Development

“…The next set of papers discusses applications of the various analytical tools towards creating PAT applications for upstream unit operations such as microbial fermentation and mammalian cell culture. The contribution from Ashton et al investigates the applicability of UV resonance Raman (UVRR) spectroscopy as a probe for residual cellular DNA and RNA in mammalian cell culture medium.…”