Stem cells hold medical promise
Stem cells are the most versatile of cells: cells capable of
reproducing themselves and also of growing into different kinds of body tissue.
Stem cells are found in embryos and umbilical cords. Reservoirs of specialized
stem cells also exist within our bodies, where they wait for the signal to go
into action, repairing or replacing tissues damaged by age, injury or
disease.
When someone cuts a finger, stem cells kick in to make new skin.
They are also the reason injured lizards can grow new body parts.
If these building blocks of life can be controlled, they hold out
the promise of cures for a variety of debilitating diseases, possibly within
the next 10 years. Researchers hope stem cells will provide cures for diseases
caused by cell failure and for repairing tissues that do not repair themselves.
Heart damage, spinal cord injuries, Parkinsons disease, leukemia, bone
marrow disease and diabetes are among diseases named in connection with stem
cell research. Some researchers also hope that stem cells might eventually be
prompted to make new organs for transplant organs that might not be
rejected by the body.
Scientists say stem cell research may also hold the key to slowing
down the aging process. Among dramatic recent breakthroughs in stem cell
research, scientists have learned to rejuvenate telomeres, regulators that shut
off stem cell division, a major factor in aging.
Researchers are working at stimulating stem cells into growth in
the laboratory and learning how to direct them to diseased or damaged parts of
the body. A major challenge is how to get the beneficial cells to their
intended destinations without triggering immunities or other potentially
serious side effects. Another is how to signal the cells to turn on
and do what researchers want them to do once they get where theyre
supposed to go. Still another is how to prevent the reproducing cells from
turning into malignancies.
Excerpted from Stem cells hold promise of cures by
Pamela Schaeffer, published in NCRs special report on human
reproduction and ethics, Oct. 22, 1999. Articles are available on
NCRs Web site, www.natcath.org. Click on NCR Online
and Search NCR. Use keywords human destiny.
National Catholic Reporter, September 8,
2000
|