By
Suzanne Leigh, Medical Tribune News Service
A new study marks another milestone in scientists' quest to find
high-tech human-repair methods.
Published
Friday in the journal Science, the report follows last year's
announcement of the successful isolation and test-tube culture
of human embryo cells. These embryo cells are theoretically capable
of maturing into any type of human body cell, and scientists are
hoping one day to use them to grow human tissue, such as skin
and organs, for transplants. This breakthrough also holds promise
for pharmaceutical research, because the mature cells could be
used in developing new drugs.
Now
Mark F. Pittenger and colleagues from the Baltimore-based biotech
company Osiris Therapeutics have succeeded in culturing mesenchymal
stem cells (MSCs). These cells, which are found in adult bone
marrow, were manipulated to form cartilage, bone and fat cells
that researchers believe are identical to the human versions.
Unlike
the embryonic cells, which can theoretically produce any cell
type in the body, MSCs mature into a smaller number of highly
specialized tissues, a process known as differentiation. These
tissues can then be put back in the body to engineer their regeneration.
In
Pittenger's study, researchers isolated cells from the bone marrow
of 350 donors. The MSCs of three donors were then cultured in
test tubes under conditions favorable for differentiation. After
one to three weeks, the cells became highly differentiated. In
contrast, cultures from normal skin fibroblasts, a different type
of connective-tissue cell, did not undergo any such differentiation.
According
to Thomas Doetschman, professor of molecular genetics at the University
of Cincinnati, the culture of MSCs represents a significant advance
in the treatment of diseased or damaged bone, cartilage and muscle.
``Unlike
embryonic cells, which can be theoretically used to produce any
cell type, mesenchymal cells can differentiate directly into many
different types of tissues, making them ideal for tissue re-engineering,''
he said.
MSCs
are currently being used experimentally for breast cancer patients
whose bone marrow has been damaged by chemotherapy. At the Skeletal
Research Center at Case Western Reserve University in Cleveland,
tests are also underway using MSCs to repair torn Achilles tendons
and ripped knee cartilages, injuries that do not heal on their
own.
Next
Update