Sufferers of osteogensis imperfecta have been given hope after researchers have developed a new treatment that tackles the root cause of the disease.
Osteogensis imperfecta, also known as brittle bone disease, is characterized by weak and brittle bones. The disease is caused by a lack of type 1 collagen. Without type 1 collagen, bones break easily. The disease affects around 1 in 15,000 people and can vary in severity from mild to severe. The disease is most commonly caused by a mutation in either the COL1A1 or COL1A2 genes.
Currently there is no cure for the disease. Treatments can be provided, but they are focused on correcting defective bone structure rather that targeting the root cause of the disease. A new treatment could be just on the horizon, as researchers at the University of Connecticut have developed a new stem cell treatment that has proven effective in a mouse model and targets the cause of the disease.
The researchers harvested stem cells from the bone marrow of a donor and transplanted the cells into the femurs of mice with osteogensis imperfecta. One month after the stem cell transplant, 18% of the endosteal surface – the inner surface of the medullary cavity of long bones – was found to be expressing osteoblasts. Osteoblasts produce the collagen which is lacking in patients with osteogensis imperfecta, and they are essential for the formation of healthy bone tissue.
The presence of the osteoblasts demonstrated the stem cells had differentiated and engrafted. This was confirmed at the 3-month and 6-month stage post transplantation. In areas where the stem cells had differentiated and replaced mutant collagen, bone structure and bone strength had improved.
“Locally transplanted donor bone marrow stromal cells (BMSCs) can improve cortical structure and strength and persist as continued source of osteoblast progenitors in the OIM mouse for at least 6 months,” wrote the researchers.
The study – Engraftment of skeletal progenitor cells by bone directed transplantation improves osteogenesis imperfecta murine bone phenotype – was recently published in the journal Stem Cells. DOI: 10.1002/stem.3133