Researchers at Harvard Stem Cell Institute (HSCI) have used
the common cold virus to create induced pluripotent stem (iPS) cells in mice,
thus eliminating the need for potentially-dangerous retroviruses.
Scientists have known how to create iPS cells from adult
cells for some time; however questions over the safety of the technique have
hampered stem cell research in this area. These questions arose because, until
now, the technique relied upon retroviruses, which actually integrate
themselves into the DNA of the new cells, and have the potential to trigger
tumor growth.
However, Konrad Hochedlinger and colleagues at the HSCI say
that they have managed to create mouse iPS cells with adenoviruses – the
viruses responsible for the common cold. The great advantage of using
adenoviruses is that they deliver the necessary transcription factors to the
cells, but are cleared by the cells after a few cell divisions, thus meaning
that they are not integrated into their DNA. “This wouldn’t be harmful in any
way because the DNA of the new cells remains unaffected,” said Hochedlinger, an
assistant professor at Harvard’s Department of Stem Cell and Regenerative
Biology (SCRB) in a news release issued by the university. “The next step is to
reproduce this work using human cells, and there’s no reason why it can’t work.
This basically provides us with a system with which to test the question of
whether iPS cells are the equivalent of human embryonic stem cells. That’s a
question that, in my opinion, hasn’t been answered yet.”
Stadtfeld M, Nagaya M, Utikal J, Weir G, Hochedlinger K.
Induced pluripotent stem cells generated without viral integration. Science.
Published Online September 25, 2008. DOI: 10.1126/science.1162494
News release: Important new step toward producing stem cells for human treatment. Harvard University Website. September 26th 2008.
