State of the researches
The 2007 report from the Agency of Biomedicine reminds that French teams have started research on human embryos from 2005, year of the first authorisations. At the end of the year 2007, 27 teams held an authorisation to research on embryonic stem cells (ESC).
In total, 88 authorisations have been delivered, of which 24 in 2007, and in France we are thinking about “the opportunity” to create a national bank of human embryonic stem cells.
Study and non therapy
The priority is now given to a fundamental cognitive research, an application in substitution cell therapy being further, in particular by the fact of an immunologic barrier and of the tumoricity of cells coming from embryonic stem cells.
It is interesting to note that the supporter of these researches want to erase the reference to the “therapeutic benefit”, currently being part of the law and previously necessary to any authorisation for research on human embryonic stem cells.
Induced pluripotent cells (IPS)
The report states: “in 2006-2007, new data have disrupted the landscape by describing a third source of stem cells which come from the reprogramming of adult somatic cells: the induced pluripotent stem cells – iPS, discovered by Pr Shinya Yamanaka. Despite the short time, these cells appear to have the same properties as CSEh, which explains the major interest they give rise in therapeutics, and this especially as, not coming from embryonic source, they are not subject to the same regulation and do create ethical problem” 1.
Despite these advances on cord blood and adult stem cells, acclaimed by the international scientific community, the Agency of Biomedicine carries on stating: “the adult stem cells are rare, most of them accessible with difficulty on a prospective way and amplifiable with difficulty. They have a potential generally limited to the tissue which shelters them, what restricts their therapeutic use. Data suggesting the existence of “pluripotent” ASC with a potential quite similar to that of HESC, in particular in the cord blood, are extremely debated”.
The future of the authorisations?
The scientific publications dedicated to promising results of adult stem cells multiply. For Jean-Claude Ameisen, chairman of the ethical committee of Inserm, “Yamanaka’s work proves that it is possible to reprogram ordinary stem cells and shows that the plasticity of cells is greater that we thought. With this technique, we cannot say anymore: There is no mean to do differently (than the research on the embryo, editor’s note)”.
Are the performances of these adult cells, whether they come from cord blood or called induced (IPS cells), not liable to challenge the authorisations of research on embryo? Indeed, these are only authorised, on an exceptional basis, “when they are susceptible to allow major therapeutic advances and on condition that they cannot be followed by an alternative method of comparable effectiveness”. The next bioethics law will have to answer this question.
1 – On these major scientific advances and more particularly on Yamanaka’s works on iPS capable of differentiate in several types of human cells, see Gènéthique No 90 and No 96.