Tilo Weber¹, Kristina Wagner¹, Joachim Wiest^2*

11th World Congress on Alternatives and Animal Use in the Life Science, Abstract overview, 2020, 114

1 German Animal Welfare Federation
2 cellasys GmbH

Corresponding author: wiest@cellasys.com

The use of fetal bovine serum (FBS) in cell culture media has different drawbacks. The
harvesting of FBS from bovine fetuses after slaughter of the pregnant parent (dam)
raises ethical and legal concerns. From a pure scientific point of view the use of FBS is
inacceptable since regional differences in type and concentration of ingredients exist
(Baker, 2016, van der Valk et al., 2010). Hence, a non-definable quality of FBS
undermines data reliability and decrease or even prevent experimental reproducibility.
However, the use of chemically defined cell culture media is still scarce.
The introduction of chemically defined cell culture media is a contribution to fight the
reproducibility crisis in the biomedical sciences and an approach to address animal
welfare concerns. Usage of chemically defined medium will eliminate some unknowns in
cell culture experiments. A procedure to develop serum free media was introduced by
van der Valk and colleagues (van der Valk et al., 2010). In the presented work, a detailed
recipe to prepare a defined DMEM / Ham’s F12 + ITS cell culture medium is given. This
medium has proven to work in our laboratory for L929 and Caco-2 cell lines in
combination with a certain plastic ware (Greiner Bio-One, Advanced-TC). To prepare the
chemically defined cell culture medium (DME /F12+ITS) mix 50% DMEM (e.g. Sigma
Aldrich, D5648) and 50% Ham’s F12 (e.g. Sigma Aldrich, N6760), add 14.7 mmol/l NaCl,
20.9 mmol/l NaCHO3 and 5 ml/l ITS (Sigma Aldrich, I3146) (cellasys, 2019). The medium
was developed for cell culture in a 5% CO2 incubator. The presented method was
employed to develop a chemically defined cell-based assay for cytotoxicity
determination according to ISO10993-5 (Wiest, 2017), furnishing a first proof of its
applicability as an alternative to cell culture media containing FBS.

Baker, M. (2016). Reproducibility: Respect your cells!. Nature 537, 433–435.
doi:10.1038/537433a;

cellasys (2019). https://www.cellasys.com/wpcontent/
uploads/2019/10/wwwSOP-G200-005_DME-F12-ITS_medium_preparation_V1_3-
1.pdf;

van der Valk, J., Brunner, D., De Smet, K. et al. (2010). Optimization of chemically
defined cell culture media – Replacing fetal bovine serum in mammalian in vitro
methods. Toxicology in Vitro 24(4), 1053–1063. doi:10.1016/j.tiv.2010.03.016;

van der Valk, J., Bieback, K., Buta, C. et al. (2018). Fetal Bovine Serum (FBS): Past – Present –
Future. ALTEX 35(1), 99–118. doi:10.14573/altex.1705101;

Wiest, J. (2017). Chemisch definiert – ein zellbasierter Zytotoxizitätsassay ohne fötales Kälberserum. BIOspektrum
23, 61. doi:10.1007/s12268-017-0768-6

cellasys, Technische Universität München and MatTek In Vitro Life Science Laboratories present recent updates about our “Tissue-on-a-Chip” at the 22nd European Congress on Alternatives to Animal Testing:

Tissue-on-a-Chip

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In this study we demonstrate a microphysiometric system based on IMOLA‑IVD device that will allow real-time measurement of multiple parameters in human small intestine tissue model (EpiIntestinalTM). The parameters are measured non-invasively, while the system provides fresh nutrients and allows programmable repeated dosing of test articles. In the presented set of experiments we have concentrated on trans-epithelial electric resistance (TEER) as this parameter was previously established to reflect an integrity of EpiIntestinal tissue model. The performance of the system was verified and baselines were established by long term incubation of EpiIntestinal tissue in IMOLA-IVD, followed by single application of 2% SDS.

The combination of classical engineering disciplines and knowledge from cell biology allows the construction of physiologically relevant models to predict processes in the human body in-vitro. In the symposium different aspects of tissue-on-a-chip systems are presented. These include a biopsy-based approach to develop personalized therapies for cancer patients. A bone-on-a-chip that allows the investigation of 3D bone organoids under mechanical load and it’s optimization using in-silico technologies. Further, the necessity of including immune cells into models of osteochondral tissues will be discussed. Examples about applications of dynamic magnetic fields to improve transfection and apply mechanical force inside living cells, a case study about a tissue-on-a-chip system for skin and intestine for applications in toxicology and aspects to employ living cells as biosensors in microphysiometrical systems are on the agenda.

At IEEE EMBC 2019 in Berlin / Germany cellasys co-organizes a symposia on:

Cells and tissue as prediction model for toxicology, drug development and personalized medicine ( organized by J. Wiest and F. Schulze )

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M. Brischwein: Development of personalized therapies for cancer with 3D tumor spheroids

Multicellular tumor spheroids are 3D models generated from various cell types, including heterogeneous tissues of solid human tumors. They have proven utility for predictive testing of patient samples to identify the most promising pharmaceutical anti-cancer treatment.

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F. Schulze: Mechanical loading of human osteoblasts in a bone-on-a-chip

Organ-on-chip systems are used to recreate the physiology of a certain tissue or organ of interest, thereby enabling more detailed investigations than conventional cell culture allows for. In this project a bone-on-a-chip system is presented that allows for control of oxygen levels and mechanical loading

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A. Lang: Modelling the crosstalk between immune cells and bone

Interaction between immune cells and bone metabolism plays a crucial role in the pathogenesis of several disorders affecting the musculoskeletal system. However, current engineering approaches exclude the immune system due to its complexity. Here, we aim to present the importance of modelling the crosstalk between immune cells and bone as exemplified by mimicking the initial phase of fracture healing in vitro.

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M. Koch: New magnetic field device for application with laser microscopes

A new digitally controlled field generator is integrated into a laser microscope. Magnetic particles powered non-invasively by the field generator treat cell populations inside a dish above the microscope lens, which can be observed in real time.

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J. Wiest: Tissue-on-a-chip

Microphysiometry is a powerful tool to monitor the energy metabolism and changes in morphology of living cells. Until now, the technique was mainly used for monitoring of cells in 2D monolayers. Now, the cellasys group showed that it is possible to monitor the extracellular acidification rate (EAR) and transepithelial electrical resistance (TEER) of 3D skin constructs in an automated assay maintaining an air liquid interface (ALI) with the IMOLA-IVD technology.

Meet us at The Lush Prize Conference 2018.

Welcome to Berlin for The Lush Prize Conference 2018: Is there an end in sight for animal testing? Can Organ-on-a-Chip replace animal use in safety testing with advanced human focused approaches?