05 Mar 2014 01:37

Creator of iPS cells decries '3 misconceptions' vs STAP cells

Shinya Yamanaka (Mainichi)
Shinya Yamanaka (Mainichi)

KYOTO (Kyodo) -- Nobel Prize-winning scientist Shinya Yamanaka decried "three misconceptions" Monday about induced pluripotent stem cells, or iPS cells, which he developed in comparison with STAP cells that hit the headlines lately.

At a news conference in Kyoto, the Kyoto University professor said one of the misconceptions is the assertion that iPS cells have a higher risk of developing cancer than STAP cells, which like iPSs can transform into any tissue in the body.

While iPS has for years been a viable alternative to the ethically challenged embryonic stem cells, a team of researchers led by Haruko Obokata, a biologist at the Riken Center for Developmental Biology in Kobe, developed STAP, or stimulus-triggered acquisition of pluripotency, cells in mice and announced the news late last month.

"What hurt us were a lot of reports that concluded STAP cells are safer than iPS cells," Yamanaka said. "The iPS cells announced in 2006 using mice and the iPS cells created now use totally different techniques. I find it quite regrettable that the reports made comparisons with the old technique."

Yamanaka, a professor at the Kyoto University Center for iPS Cell Research and Application, added that the safety of human iPS cells is being confirmed in clinical research.

The other two misconceptions he pointed out were the descriptions that the "production efficiency" for iPS cells is said to be 0.1 percent, against 30 percent for STAP cells, and that iPS cells are said to be more difficult to engineer than STAP cells.

IPS cells are made by reprogramming adult cells through the introduction of four genes into them and have been made from human and pig cells. Both iPS and STAP cells have created a buzz for their potential for regenerative medicine.

But reports say there is concern that iPS cells are more susceptible to cancer when they are implanted into the body because they are made through genetic changes, while STAP cells, which undergo no genetic changes in their making, are said to pose no such concern.

At the news conference, Yamanaka suggested that his lab would also do research into STAP cells, calling on Riken's Obokata to "allow us to do whatev

February 11, 2014(Mainichi Japan)