Overview of embryonic stem cells in cultivated meat
- European Molecular Biology Laboratory researchers grew self-organising bovine tissues from embryonic stem cells
- The tissues contained muscle, nerve and blood vessel cells
- Embryonic cells offer greater flexibility than conventional adult stem cells
- Current cell aggregates remain too small and costly for scaling
- The technique could improve cultivated meat research and tissue development insights
Cultivated steak is notoriously difficult to produce. But a new study could make it easier, at least in theory.
Researchers from the European Molecular Biology Laboratory (EMBL) Barcelona have developed a method to grow self-organising bovine tissues from embryonic bovine stem cells. These tissues contain nerve, muscle and blood vessel cells.
The process is not free of bottlenecks. Currently, the high cost and the small size of the cell aggregates (clusters of cells) mean that it would be difficult to scale. Nevertheless, it could allow researchers in cultivated meat to study muscle tissues in new ways.
Overcoming existing bottlenecks
At the moment, cultivated beef typically relies on stem cells taken from adult cows, according to EMBL. This poses several problems: while they do produce muscle, their capacity to divide is limited and they are already committed to becoming certain types of tissue.
Here, the team instead used embryonic bovine cells, which unlike adult cells proliferate for long periods and retain the ability to develop into many different cell types.
Guiding cell development, the researchers were able to generate three key components of muscle tissue: skeletal muscle cells, neurons, and endothelial cells (cells from the endothelium, the thin layer of cells that line blood vessels, heart and some body cavities), which can create blood vessels.
The cells organised themselves into three-dimensional tissue-like aggregates, without needing to be assembled. Currently, to make cultivated steaks, these cells often need to be assembled and do not self-organise.
Being able to produce endothelial cells is particularly important, according to EMBL. In living tissues, blood vessels deliver oxygen and nutrients to allow them to grow and remain healthy.
“One of the biggest challenges in cultivated meat is reproducing the complexity of real tissue,” says Marina Sanaki-Matsumiya, former postdoctoral fellow at the Ebisuya Group and currently assistant professor at the University of Tsukuba in Japan.
“Instead of growing each cell type separately and assembling them afterwards, we showed that embryonic stem cells can develop together and self-organise, mimicking real tissue development.”
The cell aggregates produced by the researchers are highly complex: within each one, muscle fibres are formed alongside endothelial cell networks and spinal neurons that interact with the muscle. This shows that multiple tissue types can be generated from the same process rather than assembled from derived adult cells.
Scaling may be costly
Yet they are still very small. While the method has been proposed as a way to improve cultivated steak production, the current scale would make this difficult.
“To produce something resembling a steak, we will need much larger tissues with more mature blood vessel networks that can support continued growth,” explains Miki Ebisuya, former group leader at EMBL Barcelona and current Humboldt Professor at PoL-TU Dresden.
Scaling would be a challenge. The process is highly expensive, due to the costs of cell culture media, making the prospect of scaling it up to fit the strictures of food production economically unfeasible.
What it could do, however, is help researchers understand how muscle tissues develop. As it contains multiple interacting cell types, it could help researchers explore the topic in ways that simpler cell cultures make difficult.
So is it the silver bullet for cultivated meat? No – the costs at the moment would simply be too high to use in mass market cultivated steak production.
But the research could be a pathway to greater understanding of how tissue in cultivated products is formed.
