The absence of tumor formation in these pigs suggests that iPSCs can safely incorporate into tissues without tumor formation, despite previous results seen in the mouse.

“Being able to safely use iPSCs without the potential of causing tumors is essential for this promising stem cell therapy to become a viable treatment option,” said Stice, a Georgia Research Alliance Eminent Scholar in the College of Agricultural and Environmental Sciences.

“We now have graduate students working on making neural cells from the human and pig stem cells to help further the studies,” he said. “The human stem cells were effective in a rodent model for stroke, but rodent studies are not rigorous enough to start human clinical trials.”

“Over 700 drug treatments have gone to human clinical trials for stroke alone based on findings in rodents and have turned out not to be viable in humans. The pigs are much more human like, and they are going to be a much better model to study strokes” said West, who is heading up a cooperative project between the UGA Regenerative Bioscience Center and stroke researchers at Georgia Health Sciences University.

“This project will improve the speed and efficiency of treatment development for stroke and many other conditions and potentially reduce the number of non-human primates used in research,” West said.

Breeding success

In addition, the group has now bred these pigs produced from iPSCs and proved the stem cells did pass to the offspring. This also opens the door for producing better animal-sourced tissue for human regenerative medicine such as islet cells that produce insulin for diabetic patients.

To further their progress, the UGA Regenerative Bioscience Center, using iPSC technology, is working with researchers at Emory University to make pigs whose cells from the pancreas would demonstrate decreased rejection in human treatments.

“The next step would be to put these pig insulin-producing cells into other animals, potentially dogs or cats suffering from diabetes to see if it will produce insulin for them without being rejected,” Stice said. “So, it’s moving forward. Never as fast as we like, but it’s moving.”

Results of these studies were published in the October issue of Stem Cells.