Stem cells toughen up fetus's brittle bones
INJECTING stem cells into a developing fetus might sound risky, but it could prolong the lives of children with brittle bone disease.
Nicholas Fisk and colleagues at Imperial College London studied mouse models of human type III brittle bone disease, or osteogenesis imperfecta (OI). The genetic defect - detected in human fetuses by DNA testing or ultrasound - disrupts collagen production, leading to weak bones and stunted growth. Those with type III OI suffer fractures while in the womb and rarely survive beyond early adulthood.
Fisk's team injected human fetal mesenchymal stem cells through the wall of the uterus into 14-day mouse fetuses. At the age of 3 months, treated mice had suffered just one-third of the long-bone fractures compared with untreated mice. Their bones were also stronger and their leg bones longer.
While drugs exist to treat the disease, stem cell transplants seem to have extra benefits, such as this boost in limb length, says Fisk. In fact, the treatment has already been tried in the US on three children with OI whilst still in the womb, with promising early results seen after the babies were born. Fisk, who last week presented the work at the annual meeting of the International Society for Stem Cell Research in Cairns, Australia, believes the treatment should now be offered on a case-by-case basis. Other experts caution, however, that a full clinical trial in people is needed first.
