Pancreatic mesenchyme plays central role in the formation of mature beta cells

November 20, 2017

There's a long way to go before we can generate the type of cell that we are born with, but that's where the field needs to go, according to Hebrok. "Those are the most effective cells we can get," he added.


For the last several decades, much of the work in the field has focused on the pancreatic epithelium -- the tissues and cells in developing embryos that give rise to the mature organ and all the mature cells therein. But in recent years, Hebrok and others have turned their attention to the mesenchyme, a gelatinous mass of cells in the embryo that surrounds the developing pancreas and eventually forms much of the body's connective tissue.

The mesenchyme's role in diabetes has been something of a mystery -- largely because it is difficult to study. Even so, scientists have known for a few years that the mesenchyme provides some sort of chemical signals that drive early development of the pancreas.

Wanting to know the specific role the mesenchyme plays at each stage of a mammal's development, Hebrok and his colleagues found a way to manipulate it, making it disappear at various stages in mice by injecting it with a toxin that specifically targeted its cells. This allowed them to take snapshots of the mesenchyme's role in development.

Surprisingly, they found that it has a profound effect on the pancreas and its mature beta cells even late in development. Targeting the mesenchyme at these later stages caused the mice to lose their full number of beta cells.

"We now know that the mesenchyme is required for the expansion of pancreatic cells, including beta cells," Hebrok said.

With the system worked out, the researchers now can begin to search for the molecules that the mesenchyme produces at those different stages. Those could then be used to generate functional beta cells in the laboratory and may suggest ways to keep mature beta cells alive in adults.

Source: University of California, San Francisco