Spinal cord injuries can result in partial or full paralysis, depending on
how extensive the damage is and the injury's location. When the nerves in the
spinal cord are damaged, conventional medicine does not have a way of repairing
them. Stem cell therapy for spinal cord injury is a controversial option that
has the potential to heal nerve damage.
The spinal cord contains the nerves by which the brain communicates with the
rest of the body. Just as an appliance cannot work if someone cuts its power
cord, the brain will not be able to communicate through damaged nerves in the
spine. The part of the spine that contains the damaged nerves will be the point
below which the individual could become paralyzed, as nerve impulses will no
longer be able to pass through those nerves.
Stem cell therapy for spinal cord injury works by reestablishing the severed
nerve connections in the spine with new nerve cells. Doctors do this by
injecting stem cells into the damaged area of the spine. These are cells that
are what scientists call pluripotent, meaning they are undifferentiated cells
that can become any kind of cell in the human body. When these undifferentiated
stem cells are placed with cells of a particular type, they transform themselves
into that kind of cell. Therefore, when stem cells are injected into an area
containing nerve cells, they will turn into new nerve cells. These new nerves
can recreate the connection between the part of the spine above the injured area
and the part of the spine below the injured area.
This therapy has the possible benefit of helping cure paralysis due to a
damaged spine, but the use of stem cells makes it a controversial topic. One
source of these stem cells is fertilized human blastocysts, the stem of cells
that grows into an embryo, that laboratories create from donated eggs and sperm.
These embryonic stem cells are removed from the blastocyst, and scientists allow
the individual stem cells to continue dividing into new stem cells. This process
eventually creates large stem cell lines for use in research or medicine. Many
individuals say that using these stem cells is immoral because they believe that
harvesting stem cells from a human blastocyst is the moral equivalent aborting a
human fetus.
Research is uncovering new sources of adult stem cells that doctors could use
in stem cell therapy for spinal cord injury. These are stem cells that are
present inside the adult body, such as in bone marrow, and not harvested from
blastocysts. Since these stem cells come from an individual's own body, their
use does not attract the kind of controversy that surrounds the use of embryonic
stem cells.
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