They aim to diminish the effects of a crippling condition called osteogenesis imperfecta, more commonly known as brittle bone disease, which causes the repeated fracture of bones even before birth. Trauma sustained during delivery can be fatal, and on average, infants who survive risk suffering up to 15 fractures each year.
The condition is caused by an inability of the body to produce collagen, the most integral protein in the formation of connective tissue and an essential structural component of bones, skin, and ligaments.
Brittle bone disease impacts around one in every 25,000 births for individuals of European descent. Those affected lead lives fraught with debilitating injuries and subsequent lifelong physical disabilities. As of yet, there is no cure.
Stem cell research provides scientists with the unprecedented opportunity to treat pernicious conditions like brittle bone disease by restoring damaged or altogether deficient tissues.
Stem cells are undifferentiated, meaning that they are not yet genetically defined and can therefore specialize as any type of cell in the body. The team plans to harvest stem cells from the inner cell mass of terminated pregnancies. They will then inject the fetal cells into babies whose DNA exhibits coding errors that result in osteogenesis imperfecta. Their hope is that the cells will target bone growth by effectively forming collagen.
Two children have previously received stem cell transplants in utero for the treatment of brittle bone disease.
“The oldest child to have received the treatment is now 13 and is performing better than expected and is still growing,” said Cecilia Gotherstrom of Karolinska Institutet’s Department of Clinical Sciences, Intervention and Technology.
But in order to know with certainty that the therapy is successful, researchers must conduct a full-scale clinical trial.
The trial will involve 30 babies, with half receiving treatment in utero and the other half receiving treatment after delivery. For the following two years, all participants will receive stem cell transplants every six months. The researchers will then compare the number of fractures incurred by the children who received stem cells in the womb with those who received injections after birth. Finally, they will compare results with data collected from children who suffer from brittle bone disease but who did not receive stem cell transplants at all.
“If we could reduce the fracture frequency, strengthen bone and improve growth it would have a huge impact,” Gotherstrom told the BBC. “It is the first in-man trial and, if successful, it will pave the way for other prenatal treatments when parents have no other option.”