Transplantable hearts grown in petri dishes and the regeneration of amputated
limbs were once the things of science
fiction.

But a major
breakthrough brought those dreams closer to reality on Tuesday after researchers
announced they were able to turn the clock back on skin cells and transform them
into stem cells, the mutable building blocks of organs and
tissues.

"This is truly the
Holy Grail: To be able to take a few cells from a patient – say a cheek swab or
few skin cells – and turn them into stem cells in the laboratory," Robert Lanza
of Advanced Cell Technology
said.

"It’s bit like
learning how to turn lead into
gold."

While the research is
still in its infancy, the potential benefits are "tremendous" said Lanza, who
has already found ways to cut the death rate following heart attacks in half,
restore blood to limbs which would otherwise have to be amputated and construct
a functioning kidney using stem
cells.

The use of skin cells
will eventually allow doctors to create stem cells with a specific
patient’s genetic code, eliminating the risk that the body would reject
transplanted tissues or
organs.

It also will lead to a
virtual explosion in the availability of research materials used to test new
drugs and understand how diseases like cancer, diabetes and Alzheimer’s
function. That’s because stem cells are able to infinitely replicate
themselves and can be turned into any of 220 different types of cells in the
human body. But access to stem cells has been restricted because of the
complications, both ethical and technical, of harvesting human embryos.

The new technique, while far
from perfected, is so promising that the man who managed to clone the
world’s first sheep, Dolly, is giving up his work cloning embryos to focus
on stem cells derived from skin
cells.

"The fact that (the)
introduction of a small number of proteins into adult human cells could produce
cells that are equivalent to embryo stem cells takes us into an entirely new era
of stem cell biology," said Ian Wilmut, the Scottish researcher who first
created a viable clone by transferring a cell nucleus into a new
embryo.

"We can now envisage a
time when a simple approach can be used to produce stem cells that are able to
form any tissue from a small sample taken from any of
us."

One of the greatest
advantages of the new technique is its simplicity: it takes just four genes

to turn the skin cell back
into a stem cell. This, unlike the complex and expensive process developed by
Wilmut, can be done in a standard biological lab. And skin cells are much easier
to harvest than embryos.

The
main hurdle to overcome is finding a safe way to transform the skin cells. The
current method, developed by two teams of researchers in the US and Japan,
raises the risk of cellular mutation because a retrovirus was used to deliver
four genes to the cell.

Via Times of India