Future Diabetes Treatment: Spleen Cells
Regeneration of Insulin-Making Cells Reverses Type 1 Diabetes in Mice
Nov. 13, 2003 -- It may soon be possible to halt -- or even cure -- type 1 diabetes. The unexpected key: Spleen cells.
The surprising findings come from Denise Faustman, MD, PhD, and her team at Massachusetts General Hospital's Immunobiology Laboratory. The researchers hit on a way to regenerate the insulin-making islets in the pancreas that function in response to blood sugars.
"We have found that it is possible to rapidly regrow islets from adult precursor cells, something that many thought could not be done," Faustman says in a news release. "By accomplishing effective, robust, and durable islet regeneration, this discovery opens up an entirely new approach to diabetes treatment."
Faustman and colleagues report the findings in the Nov. 14 issue of Science.
Halting Immune Destruction
Type 1 diabetes is the result of a haywire immune system. This happens when white blood cells known as T cells go bad. The T cells mistake insulin-making cells as foreign enemies and lead a devastating attack on them.
In earlier work, Faustman and colleagues found that they could stop this process. First they used part of the body's checks-and-balances system -- a protein called tumor necrosis factor alpha or TNF-alpha -- to destroy the bad T cells. Then they injected diabetic mice with spleen cells from nondiabetic mice, teaching the animals' immune systems to tolerate their bodies' own tissues.
It worked. But this still didn't take care of the damaged pancreas. Faustman thought islet transplants would be needed.
Regeneration From Adult Cells
A strange thing happened. Most of the mice, it turned out, did not need islet transplants. Somehow, their islet cells regenerated themselves.
Further study showed that the spleen-cell injections didn't just retrain the animals' immune systems. They did two other things:
- The spleen cells triggered self-regeneration of islets.
- Some of the spleen cells themselves became part of the new islets.
"These exciting findings ... suggest that patients who are developing this disease could be rescued from further destruction of their insulin-producing cells," David M. Nathan, MD, director of the MGH Diabetes Center, says in a news release. "In addition, patients with fully established diabetes possibly could have their diabetes reversed."
From Type 1 Diabetes to Lupus, Crohn's Disease, and More
Faustman's T-cell retraining technique may help other diseases besides type 1 diabetes. Misguided T cells also are at the heart of other autoimmune diseases such as lupus and Crohn's disease.
Kathryn Hentz is president of the Iacocca Foundation, which funds innovative approaches to a diabetes cure.
"It may someday be possible to apply [Faustman's] technique in reversing rheumatoid arthritis, multiple sclerosis, and lupus," Hentz says in a news release.