Diabetes researchers, investigating how the body supplies itself with insulin, discovered to their surprise that adult stem cells, which they expected to play a crucial role in the process, were nowhere to be found. Many researchers had proposed that adult stem cells develop into insulin-producing cells, called beta cells, in the pancreas.
Instead, the beta cells themselves divide, although slowly, to replenish their own population.
In animal tissue, insulin-producing beta cells glow red and green with dyes that indicate mulitple rounds of cell division. Credit: Children's Hospital of Philadelphia