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NEW ORLEANS -- Using undifferentiated stem cells to grow pancreatic beta cells and transplanting edited porcine beta cells were two novel approaches to curing diabetes that researchers discussed here.

The first method involves taking stem cells and "training" them to become beta cells that could then be transplanted into a human with diabetes, said , of Harvard University's stem cell research department.

"Our mission is to teach cells to become insulin-producing beta cells," said Cowan at at the annual meeting of the American Diabetes Association. "We're already making a mature insulin producing beta cell that is glucose sensitive," he added, "so the first step is already done."

And at least a couple of companies, including ViaCyte and , have already begun phase I trials of transplanted cells that were grown in a lab, said Cowan. derived from stem cells, but "encapsulates" them so that immunosuppressants aren't needed.

But Cowan added that their lab is exploring another possibility that wouldn't involve encapsulation: biologically modifying the cells so that the body won't recognize them as foreign. The dream would be to have a "quality controlled, off-the-shelf" product, said Cowan, but conceded that the possibility is at least a decade off. But one encouraging sign is that the work that the lab has done was done at a large enough scale that it could potentially treat people.

"It wasn't easy," he said, adding that it took a decade of work to get there.

Do Pigs Have the Cure?

There are only about 7,000 or 8,000 deceased donors who have a pancreas that can be transplanted, said , at the University of Pittsburgh, in the same session. Given that limitation, he pointed to another possibility: using beta cells from pigs.

"Clearly, we'll never solve the problem of diabetes through deceased human donor islets," he said. "And so we'll have to look somewhere else if we want to solve it."

A stumbling block to using animal sources, such as pigs, for islets has been the human body's propensity to reject them. Cooper's solution: edit the their genes, which he said is possible with the latest advances in gene editing. "It's the first time that we can actually modify the donor rather than just treat the recipient, and that's a very big step," said Cooper. "The pig will be the answer to this problem."

But he has had difficulty funding for his research, he said. The , which provides funding for diabetes research, rejected Cooper's request for funding. He estimated that they could do a monkey trial, in which the primate is made diabetic and then given new, functioning beta cells -- with $2 million.

have been done before, with mixed results, but the idea is feasible. However, much more research is needed to understand safety and efficacy, according to . "The evidence is very minimal that transplantation could hurt the patient," said Cooper. The pigs would come from clean, bio-secure facilities, of which there are a couple already in the U.S., he said.

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