Injectable Bone

Here is a cool idea. Researchers in Britain have come up with injectable bone:

"Injectable bone is the first delivery system for stem cells and growth factors that forms a material with the strength of a bone," said Robin Quirk, a pharmacist and co-founder of RegenTec -- the University of Nottingham, In England, spin-off company commercialising the technology.

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Quirk said he hopes that injectable bone might one day reduce or eliminate the need for bone-grafts to repair skeletal defects and fractures -- which often require painful invasive surgery.

Not only does the technique reduce the need for dangerous surgery, it also avoids damaging neighbouring areas, said Kevin Shakesheff, a tissue engineer and drug delivery pharmacist at Nottingham who masterminded the breakthrough.

The technology's superiority over existing alternatives is the novel hardening process and strength of the bond, said Quirk. Older products heat-up as they harden, killing surrounding cells, whereas 'injectable bone' hardens at body temperature -- without generating heat -- making a very porous, biodegradable structure.

"Because the material does not heat-up, surrounding bone cells can survive and grow," added Shakesheff.

The invention emerged from a combination of research into implant able scaffolds that encourage new bone to grow and new techniques to deliver stem cells and drugs to specific sites. These studies spawned the new concept of an injectable matrix as the building block for tissue regeneration, said the researchers.

OK, so it is not bone in the strictest sense. What it appears to be a scaffold that hardens but also encourages the growth of osteocytes (the cells that make bone) and blood vessels.

This reminds me a story a while back where they were growing artificial hearts on protein scaffold taken from an animal heart. The significant common theme in both stories is the use of Extracellular Matrix (ECM) to help assist the growth and development of stem cells. ECM is the protein and polysaccharides that are between cells. It performs structural functions like holding tissue together, but we are beginning to understand that it also performs developmental functions like encouraging stem cells to differentiate into the right thing.

I am just speculating here, but it sounds to me like this injectable bone has co-opted this technique by mixing some biodegradable lattice with elements of the growth factors, ECM, and cells needed to differentiate into bone tissue. It would be interesting to find out whether you could growth and entire bone by putting it in a mold. Now that would be cool.

Hat-tip: Slashdot