14 Jun 2012

What are stem cells and iPS ?

Illustration for article: What are stem cells and iPS ?
Embryonic stem cells can give rise to all types of cells and tissues, but there are official issues involved in their use. Induced pluripotent stem cells are adult cells which have been reprogrammed to give them the potential of embryonic stem cells. But without the ethical problems! Because they can transform into different types of cells, stem cells have promising therapeutic prospects for rebuilding an injured organ or tissue.

A rejuvenation programme

Induced pluripotent stem cells (iPS) are produced from adult cells which have been differentiated to restore their pluripotency via genetic modifications.

In fact, researchers take cells from a given tissue (skin, blood, etc.) and insert a mixture of genes into them. These are used to dedifferentiate the cells which then have the ability to specialise and proliferate, specific to embryonic stem cells, restored.

A new source of cells

These cells are researchers' favourites because they have the same advantages as embryonic stem cells but without the ethical disadvantages (no manipulation of embryos involved).

They are therefore a valuable source of multipurpose cells, which can be used to test new drugs, for example. Used in cell therapy, they no longer carry the risk of rejection, because it is the patient's own cells which are being grafted. But for this last application, there is still a lot of work to be done to ensure that they are totally harmless, particularly regarding the risk of uncontrolled cell proliferation. We are still a long way from using them in clinical applications.