A recent University of Wisconsin study found stem cells induced from adult cells are not entirely ready to be used in place of embryonic stem cells.

Professor of anatomy and author of the study Su-Chun Zhang said the study was initially proposed because induced pluripotent stem cells, which were originally created from human skin cells at UW in 2007, had previously been observed to perform the same tasks as embryonic cells, which can transform into any type of cell in the body.

He said iPS cells are preferable to embryonic cells because they can be taken from anybody and do not provoke the controversy associated with embryonic cells.

“People were excited about our ability to generate iPS cells from everybody, including you and me,” Zhang said.

The recent study focused on iPS cells used to produce nerve cells and was based on two major questions, according to Zhang. First, it was wondered whether iPS cells could produce nerve cells at all. Second, it was tested whether the iPS cells could be used as effectively as embryonic cells.

According to Waisman Center Assistant Scientist Baoyang Hu, the study compared five lines of embryonic cells to 12 lines of iPS cells that have been guided toward producing nerve cells.

Once the study was complete, the researchers found mixed answers, Zhang said. They found iPS cells can indeed be used to create nerve cells, but are not nearly as effective or predictable as embryonic cells.

Hu said the results were a disappointment.

“It’s kind of negative results we got,” Hu said. “For the field we believe it’s very important at this moment.”

Zhang said the problems lie in iPS cells’ ability to differentiate, adding they do a poor job compared to embryonic cells.

He said the group suspects the reason for the poor differentiation is the way the iPS cells are generated, adding the next step for researchers will be to try to create iPS cells that behave like embryonic cells.

“The study really points us in a different direction,” Zhang said. “We need to look for alternative ways to generate iPS cells.”