Persistent knee problems cropping up at the most inconvenient times, such
the one that has prevented Mark Philippoussis playing at Wimbledon this
year, may become a thing of the past thanks to artificial cartilage
developed through research planned by the European Space Agency on the
International Space Station (ISS).

Every year tens of thousands of people suffer knee injuries as a result of
over-strenuous exercise or sports accidents. The ideal cure would be to
replace the defective cartilage with new material, having the same
properties as human tissue, that is readily accepted by the immune system.

Unfortunately, scientists are not yet able to produce artificial cartilage
for implantation, as under the influence of Earth’s gravity human cells
grow flat, like a pancake, rather than in the form of a sugar lump from
which the right shape can be modelled. With the benefit of weightlessness,
on the other hand, the necessary growth in all three directions might be

And that is exactly what scientists from Switzerland, Italy and Germany
are trying to test in an experiment to be carried out on the International
Space Station. Using a bioreactor, a device commonly used in laboratories
on Earth but specially adapted for use in space, the team wants to
investigate the factors that make human cells grow in three dimensions.

Once these have been understood in space, the intention is to test the
same mechanisms on Earth and use them for the routine production of human

For further information on the status of these investigations, contact:
Marc Heppener, Head of ISS Utilisation and Microgravity Division,
Directorate of Manned Spaceflight and Microgravity, European Space Agency;
phone: +31-71-565 5117, e-mail address:

The International Space Station is one of the greatest international
projects of all time, on which Europe is cooperating with the US, Russia,
Japan and Canada. Once completed, the 450-tonne ISS will have over 1200
cubic metres of pressurised space — enough room for seven crew and a vast
array of scientific experiments orbiting at some 400 km above Earth.

Europe, working through the European Space Agency, is responsible for two
key elements, the Columbus research laboratory and the Automated Transfer
Vehicle, a supply ship lifted into orbit by the Ariane 5 rocket. It is
also providing experiment facilities for the pressurised laboratories and
for the external research platforms of the Station.