LONDON ¿ Cell therapy company Cellfactors plc completed a #2.5 million (US$3.66 million) fund raising and released further animal data on its bone regeneration product, Skeletex, showing it stimulates bone growth in vivo.

The funding will enable the company, based in Cambridge, to start a clinical trial of Skeletex in periodontal disease in 2002.

Skeletex is not a cell line, but cartilage matrix containing a mixture of the growth factors and other proteins that initiate the process of bone formation in humans. It is produced in a human chondrocyte cell line.

In animal studies, Skeletex induced the formation of significant new, vascularized bone. Apart from periodontal disease, Cellfactors said the product could be used in fixing dental implants and in oral and maxillo-facial surgery. It also intends to develop the product in orthopedic reconstruction surgery.

Last month the company received a notice of allowance from the U.S. Patent Office on Skeletex, which it claims will mean that anyone wanting to grow human cells that form bone needs a license from Cellfactors. Earlier this year it made a similar claim when it was granted a U.S. patent on its method of immortalizing human neural cells. That patent covers the immortalization of neural stem cell lines using any gene or other immortalizing agent, and the use of any mechanism to control the proliferation of the cells after administration.