St. Jude researchers prove mesenchymal cell transplantation may benefit children with Osteogenesis Imperfecta

St. Jude Children's Research Hospital (ALSAC)
Thursday, 1 March 2001

(Memphis, Tennessee, March 1, 2001) Transplantation of bone marrow mesenchymal cells has the potential to correct inherited disorders of bone, cartilage and muscle, according to a study by researchers at St. Jude Children's Research Hospital, published in the March issue of Blood.

The findings suggest transplanted osteogeneic, or bone producing, donor cells engrafted in the recipient's bone could potentially lessen the clinical severity in pediatric patients suffering from the genetic disorder osteogenesis imperfecta (OI) or brittle bone disease. This disorder leads to deformities, excessive fragility, frequent bone fractures, short statures, and in its severe form death.

The St. Jude research showed for the first time that, when transplanted, mesenchymal cells – a special kind of cell found in bone marrow – have the potential to provide clinical benefits for these children. This finding is published two years to the day after St. Jude researchers published proof that mesenchymal cells could be transplanted during bone marrow transplantation.

"This is an exciting new approach because it shows for the first time that mesenchymal cell engraftment has the potential to correct inherited disorders," said Edwin Horwitz, M.D., Ph.D., a member of the department of hematology-oncology at St. Jude and the lead researcher of this study. "We believe patients with bone disorders who are treated with this approach will ultimately have a much greater chance of enhanced life since we are treating the underlying problem that causes the disorder, not just treating the symptoms."

The patients' growth rates accelerated early after treatment and were similar to those predicted for age-matched healthy children. With extended follow-up, the growth rates slowed but still exceeded the control rates. The first patient had a second growth spurt at 30 months after treatment.

Each of the patients was osteopenic (having decreased bone mass) at the time of treatment, with a total body bone mineral content (TBBMC) of 25 to 60 percent of that predicted for weight-matched healthy children. Researchers observed gains in total body bone mineral content (TBBMC) during the entire study period.

St. Jude scientists will continue to monitor the growth and bone mineralization of these patients and the durability of the engraftments.

St. Jude Children's Research Hospital, in Memphis, Tennessee, was founded by the late entertainer Danny Thomas. The hospital is an internationally recognized biomedical research center dedicated to finding cures for catastrophic diseases of childhood. The hospital's work is supported by the American Lebanese Syrian Associated Charities® (ALSAC®). All St. Jude patients are treated regardless of their families' ability to pay. ALSAC covers all costs of treatment beyond those covered by third party insurers and total costs for families who have no insurance.

For more information, or to contact St. Jude Children's Research Hospital (ALSAC), see their website at: www.stjude.org