Insulin with cord blood
According to a study carried out by Pr Colin McGuckin (Newcastle Center for
Cord Blood, Newcastle University) and Pr Larry Denner’s teams (Stark Diabete
Center, University of Texas Medical Branch), it is possible to create
insulin-producing cells from cord blood stem cells. These results open new
perspectives in the treatment of insulin-dependant diabetes (Type I diabetes),
which is a disease due to the destruction of pancreas cells which ensure the
synthesis of the hormone regulating the blood sugar level. In this study
published in Cell Proliferation of June 20071,
the researchers explain that they succeeded in transforming cord blood stem
cells into insulin-producing cells in 21 days.
Which therapeutic hopes?
These works could enable replacing the grafts of pancreatic tissue fragments
containing insulin-producing cells of the islets of Langerhans. Nico Forraz,
co-author of the study specifies “for people with type I diabetes, we
plan to use stem cells to create insulin secreting cells, but also immune
cells contained in cord blood, which could allow to “calm down” the
auto-immune roots of this disease which destroys areas of pancreatic tissue”.
Cord blood banks
If therapeutic interest of these studies is confirmed, the necessity to
obtain cord blood units in great amounts will impose quickly.
In France, the ethical and health authorities are opposed to the
establishment of private cord blood banks. For the National Consultative
Ethic Committee (CCNE), the constitution of private bank for a strictly
autologous use of cord blood is contrary to the principle of solidarity of
our health system. In 2002, the CCNE recommended public authorities to
promote an important development of cord blood private banks with
essentially allogeneic purposes2.
French situation
In January 2006, France had 5,150 stored units of cord blood, which only
ranked 16th at the global level in unit number per inhabitant. Today, in
June 2007,
5,800 cord blood units are preserved in French public banks. To be at
the same level as our European neighbours, our stock should be at 50,000.
Nevertheless, out of the four hospitals acting as public banks, two should
stop for financial reasons. Today only two cord blood banks are still
operating, in Bordeaux and in Besançon, and the bank of Saint Louis Hospital
in Paris should be operational in a short while.
This delay is tempered by French graft quality for which France is in the "leading
bunch". This way, the stake for France to remain internationally
competitive is to increase the size of its bank, while preserving the
excellent quality of its graft.
Delay to make up
The study which has just been published should contribute to recall the
emergency existing in our country to develop the preservation by freezing
umbilical cord blood. “In each cord blood, it is possible to obtain
around 500,000 stem cells", recalls Nico Forraz from the Stem Cell
Institute of Newcastle University. With 120 millions of children which are
born every day in the world, cord blood stem cells will be predominant in
the research on cell therapies.
The Virgin Health Bank
Sir Richard Branson, Virgin founder and chairman, announced in January 2007,
the creation of a new mode of cord blood bank. Virgin Health Bank will be
the first bank of this type both private and public. For around 2,270 euros,
the parents who wish it, will be able to preserve their child cord blood for
20 years.
Financed by its clients and its investors, Virgin Health Bank will give, for
free, 80% of each sample to a public bank. The remaining 20% will be the
exclusive property of the family.
Moreover, Sir Richard Branson agreed to refund all profits received by
Virgin Group to the research on adult stem cells.
1. Directed Engineering of umbilical cord blood stem cells
to produce C-peptide and Insuline ; L. Denner, Y. Bodenburg, J. G. Zhao,
M. Howe, J. Cappo, R. G. Tilton, J. A. Copland, N. Forraz, C. McGuckin, R.
Urban (2007); Cell Proliferation 40 (3), 367-380.
2. Opinion of the National Academy of Medicine of 19th November 2002 and
opinion of the CCNE of 12th December 2002.
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A revolutionary discovery
A Japanese researcher team (Pr Shinya Yamanaka, University of Kyoto) and two
American researcher teams (Whitehead Institute for Biomedical Research,
Cambridge, Massachusetts and Harvard Stem Cell Institute of Boston)
succeeded in transforming skin cells sampled from adult mice into
pluripotent cells.
Konrad Hochedlinger, from Harvard Stem Cell Institute of Boston, published
his results in the journal Cell Stem Cell. Both teams have published
their works on the Nature1
Internet site.
Pluripotent adult cells
Adult cells have been reprogrammed to be pluripotent. Up to now, the
scientific community agrees that it was impossible a differentiated cell
could return to the stage of undifferentiated and pluripotent cell. Today,
this experience shows the contrary1.
Applied to human species, these results would revolutionize all the
researches on stem cells and would make definitely useless the researches on
the embryo which raise so many serious ethical problems.
Yamanaka’s works
In last August, Mr Yamanaka has already discovered that by inserting 4 genes
in mice skin cells, called fibroblasts, these had an extraordinary potential,
during laboratory tests. But these cells called "iPS" still presented
difficulties. But then the three studies which have just been published show
that iPS cells revealed to have properties similar to those of embryonic
stem cells.
Researchers specify that they do not know if this experimental procedure may
be reproduced successfully with human cells. Moreover, one the gene inserted
is known to promote cancer. In this experience, mice which received iPS
cells have tumours.
In September 2006, Professor Yamanaka presented his precursor works during
the Congress in Rome on adult stem cells, organized by the Pontifical
Academy for Life, the International Federation of catholic medical
associations (FIAMC) and the Jérôme Lejeune Foundation (see Gènéthique
October 2006). Yet he announced to have identified the factors which
generate pluripotent stem cells from fibroblast cultures.
Today, his publications, confirmed by two other teams, win unanimous
support. For Hans Schöler, from Max Planck Institute for Molecular
Biomedicine of Munster, “it is a success as important as Dolly“, the
first cloned sheep in the world.
1. These works have been published in Nature and Cell Stem Cell from 6 June
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The cost of MAP
The Medically Assisted Procreation is expensive. In 2004, according to the
last figures from the Biomedicine Agency, 113,000 attempted MAP have been
registered in France and 17,791 children are born thanks to theses
techniques. But then, each attempted MAP costs between 3,500 and 5,000
euros.
Interviewed by Le Monde on 28th May 2007, and faced with the
increasing demands, often in situations non foreseen by law, Véronique
Fournier, public health doctor and director of the Clinical Ethics Centre of
Cochin Hospital, asks for a national debate: should national solidarity pay
for demands which are more matters of personal convenience than disease?
More and more borderline cases
Before talking about subrogate mothers or the access for homosexuals to
medically assisted procreation, we should wonder about the legitimacy of the
reimbursement of the MAP in more and more numerous borderline cases which
are subject to the appreciation of Clinical Ethics Centres?
The demands are often out of the framework imagined by the legislator: is
the recourse to MAP lawful to give a child to a 70 year-old man who froze
its sperm before chemotherapy and starts a new life with a young woman? What
should we think about a MAP demand by a 43 year-old woman who had tubal
ligation after having given birth to three children during a previous
unhappy union and wants to be again a mother?, etc.
The role of health insurance
Health insurance finances the cares which are necessary due to a disease;
its role is not to alleviate injustices; thus, Social Security does not
reimburse plastic surgery. Whereas it is planned to limit the access to
expensive technologies according to the patient age, Véronique Fournier
insists: “we should wonder collectively whether it is the role of the
society to pay for demands which are more matters of personal convenience
than disease?”.
The necessity of public debate
Véronique Fournier proposes that the disease-related infertility is
reimbursed and in the case an ethical answer would be too difficult, a
multidisciplinary commission must be seized to establish whether the
national solidarity assumes the financing of parental project. To put into
public debate what the national solidarity must finance or not, will become
an important question within the future years.
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