Biochemical
and Biotechnology -
Bone and Nerve Cells from the Placenta
Introduction
Special placental cells have recently
been cultured into nerve and bone cells, a breakthrough
that may pave the way to a regenerated cellular tissue
bank for the treatment of otherwise incurable disease.
The development has come from a blood storage facility
that has been offering umbilical cord blood for medical
treatment of leukemia and other disease. The day may
not be too far away, when placentas are used to treat
hard-to-cure ailments such as bone cancer and Parkinson's
disease, which damages nerve cells.
It has been known that mesenchymal stem cells, which
develop into bone and nerve cells, exist in bone marrow.
The Institute of Medical Science at Tokyo University
discovered that mesenchymal stem cells also exist placental
villi, tiny branchlike structures that supply oxygen
and nutrition to a baby in the womb while carrying off
carbon dioxide and metabolic by-products. Dr. Takahashi
of cell processing section developed a combination of
medicines to enhance the growth of placental mesenchymal
stem cells into nerve cells. After 24 hours of cultivation,
about 30 percent of the mesenchymal stem cells became
nerve cells. Calcium was detected from another group
of cultivated mesenchymal stem cells, which indicates
the formation of bone cells.
Stem cells extracted from embryos have attracted worldwide
attention but the use of embryonic stem (ES) cells for
medical studies has raised intense ethical debate on
the social acceptability of experimenting with fertilized
eggs that could grow to become a baby. But the use of
mesenchymal stem cells does not raise that kind of problem,
because the cells have been abandoned after serving
their natural purpose. Also, if they are stored in advance
and the type of human leukocyte antigen matches that
of recipient, anyone can receive the cells. However,
mesenchymal stem cells can develop into limited kinds
of cells such as bone and nerve cells, whereas the ES
cell can become cells of the liver, pancreas and all
other internal organs. Research is being conducted to
evolve a practical use of the method for human medical
treatment.
If the safety and effectiveness of the method is ensured,
cord blood banks may offer new medical materials to
patients with various kinds of hard-to-cure diseases.
It was often believed that the placenta was a treasure
box containing stem cells that could become various
cells and organs, and the results have upheld this belief.
Although the practical applications would be realized
in due course, the culturing of bone and nerve cells
from placenta is a major step forward in regenerative
medicine as it paves the way for utilizing placentas,
which are now a medical waste product.
Regenerative medicine is a field in which researchers
aim to produce human tissues and organs from human cells
and genes to use them for medical treatment. In-spite
of the ethical resistance, researchers all over the
world are studying ES cells extracted from fertilized
eggs as the ultimate resource cells. In March '02 Japanese
government approved the production of ES cells. But
mainstream studies use mesenchymal stem cells from bone
marrow, instead of embryonic stem cells, to produce
bone and nerve cells. The technique has already seen
practical use. For example, researchers at Nara Medical
University produced bone pieces using the technique
and transplanted one to a patient suffering from a disease
that deforms bone joints. This finding of mesenchymal
stem cells inside the placenta (and its successful culturing
to bone and nerve cells) may help cope with the shortage
of cells as input material for that kind of treatment.
Contact for more
information
Science & Technology
Wing Embassy of India
2-2-11, Kudan Minami, Chiyoda-ku
Tokyo 102-0074, Japan
Tel: +81-3-3262-2391 to 97,
Fax: +81-3-3234-4866
E-mail:tandonus@hotmail.com
