Scientists have used embryonic stem cells to generate blood — a feat that could eventually lead to endless supplies of type O-negative blood, a rare blood type prized by doctors for its versatility.
“We literally generated whole tubes in the lab, from scratch,” said Robert Lanza, chief science officer at Advanced Cell Technologies.
People usually require blood transfusions that match their own blood type: A mismatch can be fatal. Type O-negative can be safely transferred into anyone, but is only possessed by about 7 percent of the population, leaving supplies perpetually short.
The new technique, devised by Lanza and colleagues at the Mayo Clinic and University of Illinois, is still preliminary. Its safety hasn’t yet been proved in animals, much less humans.
But because blood cells are short-lived and cannot divide, there’s reason to believe that stem cell-derived blood cells could pose fewer complications than other therapeutic stem cells, which can divide unpredictably.
“The beautiful thing is that you start with one line, expand them indefinitely and generate as many as you want,” said Lanza. “It’s a literally inexhaustible source of cells for therapy.”
Lanza’s team allowed a small culture of embryonic stem cells — naturally capable of becoming any other type of tissue in the body — to divide until it numbered a few billion cells. These they treated with a chemical cocktail that coaxed the cells into whatever type they wanted: A, B or O. If they’d started with a type O-negative line, said Lanza, they could just as easily have made that, too.
Tests showed the blood cells to be identical to each other, and able to carry oxygen as efficiently as their natural counterparts.
Science… well on its way to solve the dreaded donor shortage problem.
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