Researchers grow meat from 'immortal' stem cells: How it's advantageous
A team from Tufts University Center for Cellular Agriculture (TUCCA) in the US has developed immortalized bovine muscle stem cells (iBSCs). Interestingly, these iBSCs can grow rapidly and divide several hundred times, and perhaps even indefinitely. When compared to conventional methods, the stem cells which the TUCCA researchers have developed offer a couple of advantages, which include producing more meat.
Why does this story matter?
Lab-grown meat has garnered tremendous attention, perhaps more so after the FDA granted preliminary approval for cultured chicken. However, these products are expensive and pose a challenge when it comes to scaling up. That's where the immortalized stem cells come in. It will allow companies and researchers to develop new products without having to source cells from farm animals.
Stem cells sourced from animals can divide roughly 50 times
Producing cell-cultured meat requires muscle and fat cells to possess a high capacity to grow and divide. Normally, stem cells that are taken from live animals to initiate a culture can divide roughly 50 times before it starts to get "old" and cannot be used further. Theoretically speaking, these stem cells can yield a significant amount of meat.
How are immortalized bovine stem cells beneficial?
The immortalized stem cells developed by the TUCCA team provide great benefits. For one, they can help boost meat production. Also, by making the immortalized cells widely available, it could help bring down the costs incurred and tackle challenges that occur during the scale-up processes. Importantly, it can open up new avenues in the field of cellular agriculture.
Using bovine cell lines can make studies more relevant
"Typically, researchers have had to do their own isolations of stem cells from animals, which is expensive and laborious, or use model cell lines from less relevant species, like mouse muscle cells," said Andrew Stout, lead researcher of the project. "Using these new persistent bovine cell lines, their studies can be more relevant, literally getting right to the meat of the matter," he added.
Developing immortalized bovine muscle stem cells involved two main steps
So, how did researchers create immortalized bovine stem cells? There were two main steps involved. When most cells start aging, they lose the DNA sequences present at the ends of the chromosomes, which are known as telomeres. This can result in errors when DNA is copied or repaired, lead to loss of genes, and ultimately cause the death of the cell.
The chromosomes were engineered to remain "youthful"
The TUCCA team engineered the bovine stem cells so they could constantly reconstruct their telomeres, which would lead to the chromosomes remaining in a "youthful" state. The next step toward immortalizing stem cells involved inducing the cells to continually release a protein responsible for a crucial stage of cell division, thereby allowing cells to grow faster and speeding up the process.
Stem cells would have to differentiate into mature muscle cells
Do note that stem cells are not the final product. Along with growing and dividing, the cells would also have to differentiate into mature muscle cells exactly like or similar to what you would find in steak. Fortunately, the TUCCA team found that their bovine stem cells did differentiate into mature muscle cells, but were not exactly identical to animal muscle cells.
Cells might need more time to reach full maturity: Scientists
"It's possible that they are matured enough to replicate the flavor and texture of natural meat," said Stout, adding that the team will "explore further." "They are doubling at a very rapid rate, so they might need a little more time to reach full maturity."
'Bovine stem cells will become inert material when cooked'
"...Some may question whether it is safe to ingest immortalized cells, in fact, by the time the cells have been harvested, stored, cooked, and digested, there is no viable path to continued growth," said David Kaplan, TUCCA's director. "Like natural meat we eat today, the cells simply become inert material that we hope will taste delicious and provide a wide range of nutritious benefits."
