Researchers find easier way to make stem cells

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Researchers find easier way to make stem cells

'Sprinkling' a chemical onto regular skin cells causes transformation

http://www.msnbc.msn.com/id/27149523/

Researchers trying to find ways to transform ordinary skin cells into

powerful stem cells said on Sunday they found a shortcut

by " sprinkling " a chemical onto the cells.

Adding the chemical allowed the team at the Harvard Stem Cell

Institute in Massachusetts to use just two genes to transform

ordinary human skin cells into more powerful induced pluripotent stem

cells or iPS cells.

" This study demonstrates there's a possibility that instead of using

genes and viruses to reprogram cells, one can use chemicals, " said

Dr. Doug Melton, who directed the study published in the journal

Nature Biotechnology.

Melton said Danwei Huangfu, a postdoctoral researcher in his lab,

developed the new method.

" The exciting thing about Danwei's work is you can see for the first

time that you could sprinkle chemicals on cells and make stem cells, "

Melton, a Medical Institute Investigator, said in a

statement.

Stem cells are the body's master cells, giving rise to all the

tissues, organs and blood. Embryonic stem cells are considered the

most powerful kinds of stem cells, as they have the potential to give

rise to any type of tissue.

Doctors hope to someday use them to transform medicine. Melton, for

instance, wants to find a way to regenerate the pancreatic cells

destroyed in type 1 diabetes and perhaps cure that disease.

Controversy over stem cells

But pluripotent stem cells such as the embryonic cells are difficult

to make, requiring the use of an embryo or cloning technology. Many

people also object to their use, and several countries, including the

United States, limit funding for such experiments.

In the past year, several teams of scientists have reported finding a

handful of genes that can transform ordinary skin cells into iPS

cells, which look and act like embryonic stem cells.

To get these genes into the cells, they have had to use retroviruses,

which integrate their own genetic material into the cells they

infect. This can be dangerous and can cause tumors and perhaps other

effects.

Last month U.S. researchers did the same thing using a harmless virus

called an adenovirus, but the method was not efficient. And last

week, Shinya Yamanaka of Kyoto University in Japan, who discovered

iPS cells in mice, used a loop of genetic material called a plasmid

to reformat the cells.

Huangfu tried treating the cells first with valproic acid. After she

did this, it only took two of the four usual genes to reprogram the

cells into iPS cells, she reported.