Extracellular vesicles concentration is a promising and important parameter for industrial bioprocess monitoring

Abstract

Extracellular vesicles (EVs) are membrane vesicles that are produced by cells to be released into their microenvironment. In this study, we present the EV concentration as a new factor for optimization of industrial bioprocess control. The release of EVs depends on many cell properties, including cell activation and stress status, and cell death. Therefore, the EV concentration might provide a readout for identification of the cell state and the conditions during a bioprocess. Our data show that the EV concentration increased during the bioprocess, which indicated deteriorating conditions in the bioreactor. This increase in EV concentration in the fermentation broth was the consequence of two different processes: cell activation, and cell death. However, the release of EVs from activated living cells had a much weaker impact on EV concentration in the bioreactor than those released during cell death. EVs and cells in the bioprocess environment were quantified by flow cytometry. The most accurate data were obtained directly from unprocessed samples, making the monitoring of the EV concentration a rapid, easy, and cheap method. These EV concentrations reflect the conditions in the bioreactor and provide new information regarding the state of the bioprocess. Therefore, we suggest EV concentration as a new and important parameter for the monitoring of industrial bioprocesses.

Exploring the molecular content of CHO exosomes during bioprocessing

“…The only studies conducted yet on the matter of CHO exosomes claimed an increased growth (Takagi et al 2020) and attenuated apoptosis mediated by exosomes (Han and Rhee 2018). Others suggest exosomes as potential parameter for industrial bioprocess monitoring (Zavec et al 2016). Moreover, exosomes are considered potential drug delivery vehicle, due to their specific tropism, proposedly weak immunogenicity and the ability to cross the blood-brain-barrier (Liu and Su 2019).…”

Exosomes Enter Vaccine Development: Strategies Meeting Global Challenges of Emerging Infections

“…It has also been shown that virus like particles and viruses may be contaminated with exosomes and other extracellular particles . Even they can be used for bioprocess monitoring, because the exosome content reflects the metabolic state of the cells . Exosome research is one of the hottest topics in life science and biopharmaceutical development and is very promising because with exosomes we may really interfere with cell communication and specifically transmit information into micro environment of cells …”

Kinetic and functional analysis of abundant microRNAs in extracellular vesicles from normal and stressed cultures of Chinese hamster ovary cells

“…The practical implications of this study are twofold. Differential miR and protein cargo loading suggest a use for CHO EVs as a culture diagnostic tool; indeed, the use of EV concentration as a metric for CHO culture health has already been demonstrated (Zavec et al, 2016). Both RT‐PCR and our Qubit (total miR) and Bradford protein assays provide proof‐of‐concept for the relatively quick and simple evaluation of EV cargo.…”