Scientists find recipe to grow insulin-secreting cells

WASHINGTON — Scientists announced a breakthrough that could one day free millions of diabetes sufferers from a lifetime of insulin injections.

The discovery described in the journal Cell on Thursday and led by stem cell researcher Douglas Melton is a method of growing billions of precious insulin-secreting cells en masse using human stem cells. Patients could receive a single transplant with the newly generated cells, which would have the ability to read out the amount of sugar in the blood and squirt out just the right amount of the hormone insulin.

Melton, a co-director of the Harvard Stem Cell Institute and whose son and daughter have Type 1 diabetes, said the resulting cells were “exquisitely accurate” in producing the amount of insulin a patient needed.

Cell therapy has become one of the most promising areas of diabetes treatment in those with Type 1 of the disease, in which the body is missing insulin-producing cells in the pancreas and is usually diagnosed in children and young adults. In recent years, a growing number of patients have been successfully treated through transplanted cells from cadavers.

The roadblock has been the supply of cells. They have proved incredibly tricky to produce artificially. And they are so difficult to collect from cadavers that less than 1000 patients are estimated to have undergone this procedure so far.

While Melton’s work involved transplanting human cells into mice and much has to be done before they can be tested on actual patients, diabetes researchers said they believed that the hurdles were surmountable and on Thursday were already talking about what needed to happen after they reached that next milestone.

“You’ll be able to create buckets and buckets of cells. Numbers will no longer be a limitation,” said Albert Hwa, a scientist at JDRF, a New York-based advocacy group focused on diabetes that partially funded the Harvard research.

Susan Solomon, chief executive of The New York Stem Cell Foundation, said the discovery is so significant that it would shift the direction of diabetes research. “It’s a new game,” she said.

Solomon said scientists at the stem cell foundation have already begun trying to replicate Melton’s work and are using robotics to see if the process can be scaled. She said she also expects more resources to be shifted in the coming months to the question of how to keep the body from rejecting the transplanted cells. Patients transplanted with cadaver cells have to take immunosuppresants, which can have severe side effects, to prevent their bodies from fighting off the foreign cells.

“If you don’t solve the autoimmune attack that killed those cells in the first place you are basically doing stupid mouse tricks as they say,” she explained.

The process of mass producing the cells involves coaxing human stem cells to turn into the beta cells of the pancreas that are responsible for producing insulin. Melton described the work, which took 15 years, as akin to creating a new recipe for a “very fancy” raspberry chocolate cake with vanilla frosting. In a conference call with reporters, he said that it was clear what components needed to go in the mix but it took a very long time to perfect the order and timing.

“These cells respond to multiple glucose challenges,” Melton said. “You can think of it as breakfast, lunch and dinner. Each time we gave them a sugar challenge they secreted the right amount of insulin.”

Jose Olberholzer, a professor of bioengineering at the University of Illinois whose research is focused on diabetes, described the treatment as akin to creating a new “mini-organ” in a patient’s body.

“It would be a functional cure for a patient,” Olberholzer said. “The underlying disease would still be present but the fact that these insulin-producing cells are there would mean that they would effectively have normal lives.”