Real-time monitoring of the physiological state of CHO cells in bioreactor by using a dual spectroscopic strategy

Abstract

Background Bioprocesses of mammalian cell culture have become essential in pharmaceutical fields for the production of recombinant therapeutic proteins such as monoclonal antibodies or for tissue therapy. Following the FDA’s recommendation to apply Process Analytical Technology (PAT) approach as the mean to control production processes and ensure the quality of the end-product for patients, Near Infra-Red (NIR)and dielectric spectroscopic technologies have gained great attention over the past decade as online tools for cellular bioprocesses monitoring [1,2]. In such processes, cells are one of the most critical parameter, because their physiological state directly impacts the final product titer through their productivity as well as the product quality. Animal cells are typically classified into viable or dead entities via Trypan Blue exclusion technique, but lysed cells are not accounted for, although they could represent a significant proportion of the cell population in bioreactors. In addition to reducing productivity, cell lysis causes the release of intracellular proteases and glycosidases, which can degrade secreted recombinant protein of interest. Therefore, they should be considered for optimal control of processes. In this work, we propose the first online strategy combining NIR and dielectric spectroscopies for in-depth characterization of cellular growth and physiology of CHO (Chinese Hamster Ovary) cells cultivated in bioreactors.