Blog from cross-project collaboration: Successful use of 3DLife methodology across species

Today conferences are held online because of the coronavirus, and it is quite difficult to find new collaborators. But back in September 2019, the third annual conference of Digital Life Norway, that was held in Tromsø, resulted in a collaboration where knowledge from cultivating human cells in 3-dimensional (3D) matrices has improved cultivation of whale cells used for testing environmental pollutants in the sea.

The Digital Life 2019 conference brought together researchers from all over Norway working in a wide variety of scientific fields. At this conference, we presented our project 3DLife at NTNU/SINTEF with professor Berit L. Strand as project leader.

3DLife delegation at 3rd DLN conference, Tromsø. From left to right: Daria Zaytseva-Zotova, Andrea D. Hoel, Berit L. Strand, Maria B. Hesjedal, and Hanne Haslene-Hox.

In 3DLife, we design 3D materials that mimic properties of the microenvironment that surrounds cells, known as extracellular matrix. More and more studies reveal that the extracellular matrix is one of the key elements in the regulation of cell function: the chemical, biological, mechanical, and dynamic properties of the matrix can direct cell fate, and, hence, must be thoroughly investigated if we want to accurately replicate in vivo conditions.

Can 3D culture also make fish and whale cells thrive better?

After our talk in Tromsø, we met professor Anders Goksøyr and his colleagues from the dCod 1.0 project at the University of Bergen (UiB). They develop new tools for testing effects of environmental pollutants in the sea using in vitro models based on fish cells and whale cells as well as precision-cut fish liver tissue slices.

Cultivation of fish and whale cells is not a trivial task. The most practical approach is to culture the cells in regular plastic dishes. However, in plastic dishes cells can lose their tissue specific functions because in nature they usually grow in 3D environment.

To study if the 3D culture can extend the culture time for the fish and whale cells and tissues beyond what is currently possible, we applied for a Digital Life Norway cross-project grant.

No advantage for cod liver tissue…

Our joint project consisted of two main parts. The first part was focused on cod liver tissue and cells. Cod precision-cut liver slices is a well-established experimental model used for screening of environmental pollutants. However, the liver slices lose metabolic activity during long-term cultivation.

We wanted to study if providing a 3D microenvironment can solve this issue. With this aim in mind and polymer solutions in my bag, I went to Bergen for one week.

During this period, we optimized protocols for immobilization of tissue slices and also isolation of primary cod hepatocytes. The main challenge was high fat content in cod liver (everyone in Norway is well aware of that) that resulted in some difficulties in embedding of the liver slices into highly hydrophilic materials that we use in 3DLife. Unfortunately, in our experiments we found that 3D materials do not provide any advantage for these liver constructs. Because of the lockdown announced at that time, we decided not to continue further studies in this direction.

…but a success for whale cells!

Fin whale fibroblasts in 3D gel at day 3 of culture. Green – F-actin staining, blue – DAPI stained nucleus.
(D. Zaytseva-Zotova, joint project dCod 1.0–3DLife )

We got more exciting results when we tried to culture fin whale fibroblasts in 3D. Only a few research groups in the world have knowledge of how to isolate and culture these rare cells, one of them is the group of professor Anders Goksøyr in Bergen. In the 3DLife project we mainly work with human primary fibroblasts. Whale fibroblasts are very different: interestingly, they are much bigger in size and grow extremely slowly. It took almost two months to grow a substantial amount of the cells for the experiment. But it was worth it! We were very lucky to see that viability of whale cells in 3D materials was high and morphological changes were observed in majority of the fibroblasts. The latter is an important indication that the provided microenvironment is suitable for these cells.

We would like to thank the Centre for Digital Life Norway for supporting this collaboration. I also would like to thank the dCod 1.0 team and especially professor Anders Goksøyr, dr. Roger Lille-Langøy, and dr. Fekadu Yadetie for inviting me to UiB and helping with all the experiments, and all my colleagues from 3DLife project, especially professor Berit L. Strand and our colleagues from SINTEF: Hanne Haslene-Hox, Øystein Arlov, and Anette Vikenes.

By Daria Zaytseva-Zotova, postdoc at Biopolymers and Biomaterials group, Department of Biotechnology and Food Science (IBT), NTNU
Published Mar. 16, 2021 1:25 PM - Last modified Apr. 6, 2021 3:01 PM