[media-credit name=’UW Communications’ align=’alignnone’ width=’648′][/media-credit]Stem-cell research is one step closer to clinical applications in humans due to a new discovery reducing contamination in the potentially beneficial therapy.

University of Wisconsin and WiCell Research Institute scientists have created a recipe that allows researchers to efficiently develop stem cells without the use of mouse-derived “feeder” cells, which scientists have long suspected could interfere with clinical treatment in humans.

This new discovery follows a recent study conducted at the University of California that confirmed scientists’ suspicions of the existence of animal proteins in most, if not all, federally approved stem-cell lines. This experiment encouraged supporters of stem-cell research to further advocate for the controversial creation of additional stem-cell lines.

Currently, most researchers use mouse feeder cells grown from mouse embryos to create an environment for stem cells to grow. The undifferentiated stem cells can then be coerced into hundreds of different cell types in the body and could potentially be beneficial in regenerating cells in humans, such as neurons in Parkinson’s or Alzheimer’s disease patients.

But the presence of animal materials in stem cells could potentially prevent clinical trials in humans because approval from the United States Department of Agriculture to use contaminated stem cells would be unlikely.

Senior WiCell scientist and lead researcher Ren-He Xu made the discovery, which was published Thursday in the journal Nature Methods. UW professor of anatomy James Thompson, who was the first to culture embryonic stem cells, also co-authored the paper.

Xu found the protein known as fibroblast growth factor 2 can accomplish the same role as the feeder cells, but without the contamination.

The depletion of animal products in stem cells would allow for scientists to grow cells more efficiently, according to Xu. He said the process was previously very tedious because scientists were required to generate mouse feeder cells.

However, Xu said, now scientists simply have to purchase his solution and add it to the culture.

“I am very happy that we can reduce workload and make the culture [of cells] easier,” Xu said.

UW associate professor of human oncology Steven Clark said although the new development is not surprising, it is still a good, practical breakthrough.

Clark added this advancement would aid in the many developments that must still be discovered to use stem cells in a person’s brain. He explained the stem cells must be developed into different types of cells, such as motor neuron cells, because the direct insertion of stem cells into a person causes benign tumors.

“It will make it easier to maintain the cells [and also to] coax the cells into developing different cell types,” Clark said.

Xu and the other researchers have been studying embryonic stem cells for the past year, and they plan to continue research aimed at narrowing the scope of their work by observing how a single molecule affects stem cells. Xu also expressed the urgency in his research to make further developments.

“It will be a fascinating new area to study,” Xu said.

Although the largest source of contamination from the feeder cells is no longer a problem for researchers, there are still several other possibilities for contaminants, and thus scientists have more work to do before stem cells benefit humans directly.