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Transplanting living tissue
from person to person is a
standard surgical procedure.
Successful organ
transplants between humans
have created an increased
demand for donor organs.
This demand has vastly
outgrown the supply of
organs available.
Closing the gap between
supply and demand is not
easy. The tissue of the
donor and the recipient need
to be compatible, so that
rejection does not occur.
The tissue also needs to be
collected in a strict
medical environment.
Around half of all people
who need a transplant die
while on waiting lists. The
need for organs and tissues
for transplantation
increases the pressure on
researchers to find other
ways of providing the needed
tissues.
Other ways of providing
tissues include using:
- human cells in tissue
culture
- embryonic or other
stem cells to grow new
cell types.
Tissue culture is the
term used to describe
growing specialised human
cells such as skin, blood
and ligament cells in the
laboratory. Tissue culture
is a very important method
of providing healthy tissue
for transplantation. It is a
very useful technique,
because the tissue produced
has developed from a
patient's own cells; the
body may try to reject cells
from a different person.
For more than 25 years,
skin cells have been cloned
to produce healthy skin for
people who require skin
grafts after burns or
accidents. Healthy cells are
removed from the person who
requires the cultured
tissue, separated, placed in
a container of liquid
nutrients and kept under
conditions that enable them
to multiply.
Specialised adult cells
can also be cloned in this
way, but they usually stop
dividing after about 20 cell
divisions. Therefore, with
current technology, very
large patches of skin cannot
be produced.
Increased understanding
of the mechanisms of
transplant organ rejection
means that organs from other
species may soon be used as
an alternative to human
tissues to help alleviate
organ shortages. |
