Cell culture was initiated in the early 20th century with simple salt solutions. Over time, more complex solutions were developed – for example using sugar for energy supply and amino acids for protein production. Scientists also added various protein extracts from animals to make the cells grow. It took off in 1958 when researchers discovered that fetal bovine serum (FBS) was an additive that could make cells thrive, both normal and cancerous. It has worked very well, despite both animal ethics and scientific concerns – which is why no one has really tackled developing a medium with defined content and without animal proteins.
For example, animals cannot be used for cosmetic testing in Europe. But they are used indirectly through FBS, which is a by-product of the meat industry.
Despite both ethical and scientific shortcomings, it has been difficult to rule out FBS. But in 2018, researchers in Lund started using different human proteins needed for cell survival in a cell culture medium. It took until 2023 before the results were published.
"It was something unique and I wanted to trust it. We have developed a completely animal product-free cell medium and it worked immediately – we could repeat with great precision. We have used it on several different toxicological cell tests. What so many people have been working on for so long was surprisingly easy, after all," says Stina Oredsson, biology researcher at Lund University.
Giving away the recipe to all researchers
The researchers have now chosen to publish the 'recipe' openly, and since the composition – unlike FBS – is well-defined, anyone can produce it. This has sparked a lot of interest in many parts of Europe and also with the US Food and Drug Administration (US FDA), not least because it can be used to grow normal cells but also in cancer research.
"Adding FBS to a cell culture medium is like working with a black hole. You don't really know what it is because it can have a different composition due to different conditions. We show that it is possible to grow cells successfully with a completely defined and animal product-free medium," says Stina Oredsson.
Why are these results so interesting?
"There are major reproducibility problems in research. Research is also expensive and it takes a long time to develop drugs. Our results mean that growing human cells is closer to the environment in which they normally grow. It is scientifically better because we know what we are working with. A chef does not cook with unknown ingredients," says Stina Oredsson.
The scientific study was first published in Toxicology Reports.
Now a new scientific article containing both the recipe and method for producing the animal-free cell culture medium has been published in Methods X.