Scientists turn stem cells into pork
By MARIA CHENG, Physorg.com, January 15, 2010
Scientists at the Eindhoven University of Technology in the
Netherlands announced today creation of pig muscle from stem cells that one day
may serve as a new food source. Although the Dutch scientists have been growing
pig cells since 2006, they believe that their recent findings bring them closer
to actual tissue that can be consumed by humans.
"If we took the stem cells from one pig and multiplied it
by a factor of a million, we would need one million fewer pigs to get the same
amount of meat," said Mark Post, a biologist at Maastricht University who is
involved in the In-vitro Meat Consortium, a group of Dutch academic institutions
that are collaborating at developing edible products using cell culture
"Artificial" meat is grown in the laboratory using tissue
culture techniques that have been available for decades. This involves
providing the cells with a nutrient mixture that resembles the natural
environment in the body. While it has been previously known that cells can be
grown outside of the body and that hypothetically enough animal cells could be
made to generate a tissue that could be large enough to be eaten, the problem
historically has been that muscle cells do not multiply to the extent
necessary. Muscle and other cells typically reach a limit of multiplication
outside of the body, called the Hayflick limit, after which they can no longer
be expanded. This problem was solved in part by the use of muscle stem cells.
Many types of stem cells express the enzyme telomerase which allows the cells to
make copies of themselves with having to abide by the Hayflick limit.
Implications of artificial meat could be tremendous. From
a medical perspective, cells could be made that possess specific
characteristics, such as reduced fat, or enhanced concentration of nutrients.
Although it is possible to create whole animals through genetic engineering,
such as transgenic pigs, the ability to precisely control the genetic
manipulation is much higher when you are dealing with muscle stem cells as
opposed to a whole animal.
One interesting implication of artificial meat is the
impact it would have on the environment. Oxford University's Dr. Hanna Tuomisto,
an expert on environmental impact of food production stated that switching to
lab-produced meat could theoretically lower greenhouse gas emissions by up to 95
percent. Both land and water use would also drop by about 95 percent, she said.
"In theory, if all the meat was replaced by cultured meat,
it would be huge for the environment," she said. "One animal could produce many
thousands of kilograms of meat." In addition, lab meat can be nurtured with
relatively few nutrients like amino acids, fats and natural sugars, whereas
livestock must be fed huge amounts of traditional crops.
Unfortunately, using present tissue culture conditions the
cost to make one strip of bacon would be approximately $10,000 stated one
industry expert. Thus while the technology exists, feasible implementation
still seems far away using technologies available today.