Mesoblast Limited of Melbourne, Australia, a biotechnology company that develops adult mesenchymal precursor stem cell technology for the regeneration and repair of bone and cartilage, has announced that it will commence a pilot trial at the Royal Melbourne Hospital to assess the safety of its specialized stem cell technology in up to 10 patients suffering from nonunion of long-bone fractures. Harvesting, culturing, and expansion of patients' stem cells (an 8-week process) will take place at the Peter MacCallum Cancer Institute's cell therapies laboratory in Melbourne under cyclic GMP conditions. Results from the trial, including bone regeneration as an early indicator of efficacy, should be available by 3Q 2006. Preclinical in vivo studies have demonstrated that stem cells produced using Mesoblast's technology are capable of rapidly generating new bone growth and new blood vessels without the need for additional surgical procedures and bone grafts. 

Mesoblast intends to employ its adult stem cell technology in the treatment of a variety of bone and joint diseases, including bone fractures and spinal disease and degenerative intervertebral disc disease, as well as for the regeneration of damaged joint cartilage (knee arthroscopy for chronic osteoarthritis and acute cartilage tears). While initial studies will employ autologous mesenchymal stem cells, it is anticipated that allogeneic mesenchymal precursor cells will enable "off-the-shelf" products.

Mesenchymal precursor cells can be isolated from bone marrow, fat, skin, and a variety of other sites in human adults and are easily expanded in vitro. Under appropriate conditions, these cells can differentiate into bone, cartilage, fat, cardiac muscle, and blood vessels. They are capable of producing the type of proteoglycans that are lost from degenerated intervertebral discs, and inducing growth of new arterioles in the heart.