Bony breaks

Among the successes recorded in
the field of tissue engineering (the
development of spare parts for the
body), the growth of bones is one.
"This is exciting because we have
been mimicking the natural process
of development," says A Hari Reddi,
of the biology and orthopaedics
department at the Johns Hopkin
Medical Centre at Baltimore, US.
The key to the recent success is the
knowledge of a family of molecules
called bone morphogenic proteins
(BMPs).

Charles Cohen, chief scientist at
Creative Biomolecules, working on
developing products from bone proteins, said, "We are working on the
body's own signalling molecules.
The BMP sign tells the cell to 'go'
and their neighbourhood tells the
cell whether to be bone or cartilage."