The science of cultured meat
To make cultured meat, and fish a reality, many innovations and breakthrough are still to be achieved. To the present day, the method of growing (animal) cells on a scale required to produce meat does not exist. To reach this level of technology research on new methods or using well established ones as a basis will be needed. There are four innovation areas where collaborative effort is necessary to make cultured meat a reality. Here you see a schematic overview of these innovations. For a more detailed explanation please look at the literature page.
Isolate and optimize cell line
Muscles are made of muscle tissue which is mostly made out of muscle cells. To make cultured meat we would need as much muscle cells as there are in a typical steak. If you can imagine that the first cultured hamburger (85gr) was made out of 10.000 muscle fibers, each containing 1.5 million cells you can understand the enormous amount of cells needed to make cultured meat on large scales.
While normally constant cell division happens in a cow or other animal, cells do not really like to divide too many times. One of the reasons for this is that high cell division might be a sign of uncontrolled growth. There is also a natural limit on the amount of time cell can dived, this is called the Hayflick limit. Muscle stem cells, also called satellite cells, have a large potential for cell division but have a lot of demands for growing conditions. To circumvent these difficulties we can make use of different types of stem cells like embryonic stem cells. Unfortunately there has been little to no success in growing these cells on mass scale. A third option is using a cell type called induced pluripotent stem cells (iPSC). These cell are made by reprogramming adult cell so that they behave like stem cells.
This type of cells are used worldwide and a great amount of knowledge has been accumulated about them. These type of cells have multiple advantages like: because they are stem cells they have the potential to divide without a limit, they can grow without a surface making them ideal to be grown in large silos. Furthermore, there are sustainable alternatives for the feed medium which now contains serum (serum is a blood product of cows).
Unfortunately there has been little research on the development of iPSC from animals like cows, pigs, salmon, and tuna. We want to change this! Without the availability of these cells for scientists, research will stagnate. When researchers want to investigate a specific organ in human or mice, they can order cell from a catalog but cells from other animals are very limited. The cultured meat foundation want to initiate and promote research on iPSC in deferent species. By doing so we open up the field for other researches who are interested and want to contribute in this new field.
Develop Feed Medium
Cells need nutrients. In an animal these nutrients come from the things the animal eats. The food is broken down inside the digestion system to the very small pieces cells can use as energy or structural components. If we want to grow cells outside of an organism we will need to feed these building blocks directly to the cells. These components are carbohydrates, amino acids, and salts. If cultured meat wants to be a sustainable alternative to meat, these components will also need to be produced sustainably. There are a couple of potential technologies like: electrochemical reduction of carbon dioxide, or making use of algae.
To make cells divide without the ques from a body we need to “speak” the langue of the cells. We do this by adding so called signaling molecules to the feed medium. The signal molecules are often proteins or peptides that are caught by the cell and reacts to that interaction by dividing or any other cell behavior we want. To know which proteins or molecules these are, and how to produce these sustainably, is a huge undertaking and is heavily underfunded at the moment. The status quo of supplying cells with these signals is using a blood product of cows called “serum”. Alternatives to serum are often expansive, come from animals, or are produces on small scale because of the difficulty for scaling. The cultured meat foundation wants to promote the development of affordable and sustainable alternatives by finding partners that can use the cell lines and optimize their growth medium for these cells.
Design Scaffold proteins
To make a piece of tissue, it is necessary to use a scaffold material. The scaffold proteins are crucial for cells to make tissue bigger than 100 micrometers. The scaffold provides structure and support to the cells so they can attach to each other to form a muscle. This type of materials are often used in medical science to make small pieces of organ tissue. We can learn much from the achievements in this field, however many adjustments will need to be made to make those achievements suitable for making cultured meat. The material should be eatable, non-toxic to cells, sustainable, and produced without animals.
3D Tissue engineering
The last step in the innovation ladder of cultured meat is to make pieces of tissue larger than 100 micrometers. This can only be done when the previous steps suffice to the sustainable and scalable criteria. To make large pieces of tissue the cells on the inside of the tissue will need to be supplied with oxygen and nutrients. Normally this is done through a network of arteries and veins. A network like this will need to be designed. This is extremely difficult since oxygen only diffuses 100 micrometers through tissue. This means that every 100 micrometer there needs to be an artery to bring the oxygen to the cells. How to do this is one of the major questions in the field of tissue engineering. We can learn a great deal from this field but the criteria for creating and transplanting an organ are very different from making a piece of tissue for consumption. That is why research will be needed to figure out what knowledge we can use for our goals and what will need to be discovered.
Schematic representation of making cultured meat.
This might seem like a huge amount of work and research but there already is a large amount of knowledge available about many of the subjects. Eventually breakthroughs in cultured meat could be used for medical applications. The cultured meat foundation believe that cultured meat is a realistic solution to the increasing problems that the meat and fish industry causes. Even tough cultured meat and fish are not yet available in stores it is important that we do this as fast as possible and the amount of money currently available for this needs to increase. The stakes are too high and the potential to big to not pursue this opportunity. Help us to make cultured meat a reality! Get In Touch or Donate to our foundation.