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By injecting human adipose
tissue stem cells, some research teams from CNRS (French
National
Scientific Research Centre) and INSERM (French
National Institute for Health and Medical Research)
managed to regenerate human muscle cells, without any rejection reaction.
This work, promising in mice, is hopeful for the treatment of muscular
diseases, particularly Duchenne muscular dystrophy1.
Blood and cardiac cells
Based on the injection of immature cells
likely to acquire, in an enabling
environment, the morphology and the function of deficient cells in an
injured tissue, the cell therapy particularly concerns adipose tissues.
Adipose tissues represent about 10% of the mass of a healthy individual and
up to 50% in an obese individual; collecting adipose tissue is not an
ethical problem as the used cells result from surgery waste. In 2004, the
CNRS-Inserm team supervised by Louis Casteilla had showed it was possible to
obtain in vitro cardiac cells from fat cells. At the same
time, the Inserm teams supervised by Bernard Levy, in collaboration with
Louis Casteilla's team and Anne Bouloumié's one, demonstrated that in mice,
these cells could turn into cells that constitute blood vessels.
Reservoir of pluripotent
cells
The teams of Christian Dani, researcher for
the Inserm and director of the Laboratory “Stem cells and differentiation”,
and Gérard Ailhaud, UMR 6543 CNRS (Institute of signalling), managed to
obtain, from adipose tissue collected on young donors, pluripotent stem
cells called hMADS (Human Multipotent Adipose Derived Stem Cell). These
cells are more immature, thus have a greater potential, than the cells
obtained before. This work 1 demonstrates that in vitro, depending on
its environment, a same hMADS stem cell is able to generate a muscle, bone,
fat or cartilage cell. Once isolated and cultured, these cells showed a
strong proliferation capacity, normal chromosomes, no oncogenic character,
and no rejection reaction. The researchers noted that the cells only poorly
expressed the histocompatibility antigens responsible for graft rejection.
Duchenne muscular
dystrophy
In order to study repair potentials of the
stem cells, the team studied “mdx” mice, which are models of Duchenne
muscular dystrophy. The mice are dystrophin-deficient; dystrophin is a
protein that is necessary to the integrity of muscle fibres, for without
dystrophin muscle fibres cannot resist the strength of muscle contraction,
and then degenerate.
In humans, this genetic muscular dystrophy, transmitted by the mother,
affects 1 of 3,500 baby boys at birth in France. The dystrophy progressively
leads to muscular atrophy of skeletal, respiratory and cardiac muscles. When
transplanted in small quantity in dystrophic mice, and with no
immunosuppressive treatment, the adipose tissue stem cells were not rejected
and induced a strong, long-term human dystrophin expression. This work led
to international patenting.
1 - Journal of
Experimental Medicine, Transplantation of a multipotent cell population from
human adipose tissue induces dystrophin expression in the immunocompetent
mdx mouse, A.M Rodriguez, D. Pisani, C.A Dechesne, C. Turc-Carel, J.Y
Kurzenne, B. Wdziekonski, A. Villageois, C. Bagnis, J.P Breittmayer, H.
Groux, G. Ailhaud, C. Dani, 2 mai 2005.
.
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Created by the bioethics law, dating 6
August 2004, the Biomedicine agency has just been officially inaugurated
with the publication of the decree, dating 4 May 2005, that establishes the
functioning rules of the Agency 1.
Two fields of competency
The Biomedicine agency
is competent in two very vast fields: firstly, the field of grafts, for the
Agency replaces the French organisation for transplantations (Etablissement
français des greffes) – in this field, the Agency has to control the list of
patients that are waiting for a transplantation, as well as the register of
refusal for donation, and establishes the rules of good practice; secondly,
the field of reproduction, embryology and human genetics.
The Agency provides practitioner
accreditations in these fields and authorises prenatal and pre-implantation
diagnosis, as well as international movements of human gametes, embryos,
embryonic and fetal cells and tissues for research purposes. In both fields,
the Agency participates in establishing the rules of the activities named
above, and establishes recommendations. It announced the forthcoming
publication of the decrees about embryonic stem cells, saviour children and
living donors.
Research on embryos: the end of the
transition system
In order to come up to
the impatience of some researchers, a transition system had been established
after the bioethics law dating 6 August 2004: last February, the Ministers
of Health and of Research had authorised the importation of embryonic stem
cell lines (Gènéthique n°63). Today, the
Biomedicine Agency is competent to authorise research on spare embryos
resulting from in vitro fertilisation and not being anymore the
object of parental projects. Today, the number of frozen embryos is
estimated to nearly 120,000; 45% of these embryos are not anymore the object
of a parental project, and thus could be “used”. This number can be compared
to the 9,500 babies who were born resulting from an in vitro
fertilisation (IVF) every year in France.
« Saviour children »
The Agency is also
responsible for the authorisation for the pre-implantation diagnosis (PID),
with the objective to give birth to a child that will be helpful to the
treatment of a brother or a sister affected by a serious genetic disease.
With the approval of the law, this kind of PID overcomes another step in the
selection of in vitro human embryos; indeed, this kind of PID
consists in selecting, among the healthy embryos, the one that will be
helpful to the treatment of a child and in eliminating the others. In the
United States, to treat 9 children waiting for bone marrow transplantation,
199 embryos were conceived in vitro, 28 of which, being compatible,
were transferred in utero to give birth to 5 HLA-compatible babies.
Independence of the Agency
Within the Agency, the
streaming committee is responsible for the quality of medical and scientific
expert opinions, taking into account ethical issues. Alain Cordier has just
been appointed chairman of the committee. The composition of the committee
should counterbalance the powers of the scientists and allow the civil
society to express their concerns. The committee is composed of 24 members.
The decisions of the committee are taken by the majority of the present
members.
The annual report of the Agency
evaluates the progress of the research on embryos and stem cells, the
implementation of the PID "saviour child” and the opportunity to maintain
them. The report also assesses possible organ and gamete trafficking and
suggests measures against it. The report is then transmitted to the
ministers of Health and Research.
1 - Decree n°
2005-420 dating 4 May 2005 relative to the Biomedicine Agency (Agence de la
biomédecine) and modifying the public health code (rules and regulations
part), Official Journal dating 5 May. |
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Danielle Moyse and Nicole Diederich
carried out a study on prenatal ultrasound after the Perruche judgement. The
study was published in April 2005.
The
Perruche judgement
The judgement of the Supreme Court of Appeal,
dating 17 November 2000, declared that Nicolas Perruche should receive
compensation, for he was born disabled because his mother had contracted
rubella during her pregnancy and because of the absence of diagnosis, Mrs
Perruche “could not have an abortion”.
This decision, as well as two other
judgements of the Supreme Court of Appeal, dating 13 July and 28 November
2001, seemed to attribute to the involved doctor and laboratories the
responsibility of the disability and the birth of the child. This judgement
of the Supreme Court of Appeal admitted it was better not to come into
existence than coming into existence with a disability. The Parliament
suspended the Perruche jurisprudence thanks to a section in the law dating 4
March 2002, concerning patient rights: children cannot avail themselves of a
prejudice due to their birth and the compensation for the parents is
limited.
Towards prevention eugenics?
The initial function of
prenatal screening is to prepare labour envisaging, for example, a surgical
action at the end of delivery in case of abnormality. The Perruche judgement
might have led to prevention eugenics, as the prenatal diagnosis could have
become the tool for having the right to have a normal child. After this
decision was taken, sonographers and gynaecologists-obstetricians threatened
to cease their activity or to implement prevention eugenics by requesting
for medical abortions whenever there was the less doubt about the condition
of the foetus, in order to avoid any risk of subsequent legal action.
Practice evolution: investigation
According to an
investigation carried out between October 2002 and October 2004 among
obstetricians and sonographers, the Perruche judgement generated a great
suspension of activity - about 50%. The chairman of the association of
sonographers explained that “among radiologists that did less than 30% of
obstetrical ultrasounds within their global activity, the activity
suspension rate represented 50%”. He followed in these terms “Among
exclusive sonographers, the same activity suspension rate was found”. The
involved doctors explained that the disaffection was as well due to the fear
of legal actions and the increasing insurance premiums, as to ethics
concerns. According to practitioners, the obligation to give information
becomes problematic and the obligation to "say everything" generate anxiety,
which may induce requests for medical abortions that should not be
necessary. The phenomenon is reinforced by the progression of the deadline
for requested legal abortion, passing from 12 weeks to 14 weeks since the
law dating 4 July 2001.
In danger?
The national technical
committee for prenatal screening ultrasounds will shortly hand in a report
on fetal ultrasound to the Minister of Health. The report sounds the alarm.
The Perruche judgement forced many freelance practitioners to give up the
practice of fetal ultrasound and public hospitals are not in position to
compensate for the decreasing freelance ultrasound offer. Health care for
the poorest people is then reduced, regardless of the main objective of
ultrasounds: the diminution of perinatal and maternal mortality, and the
possibility to treat children as soon as they are born.
1 - L'échographie
prénatale après l'arrêt Perruche, Etudes, Danielle Moyse et Nicole
Diederich, April 2005.
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