Tissue engineers have demonstrated the ability to grow small amounts of structured organ tissue called organoids in recent years, and have done so with liver, kidney, and now pancreatic cells, among others:
[Researchers] have developed a three-dimensional culture method which enables the efficient expansion of pancreatic cells. The new method allows the cell material from mice to grow vividly in picturesque tree-like structures. The method offers huge long term potential in producing miniature human pancreas from human stem cells. These human miniature organs would be valuable as models to test new drugs fast and effective - and without the use of animal models.
The cells do not thrive and develop if they are alone, and a minimum of four pancreatic cells close together is required for subsequent organoid development. "We found that the cells of the pancreas develop better in a gel in three-dimensions than when they are attached and flattened at the bottom of a culture plate. Under optimal conditions, the initial clusters of a few cells have proliferated into 40,000 cells within a week. After growing a lot, they transform into cells that make either digestive enzymes or hormones like insulin and they self-organize into branched pancreatic organoids that are amazingly similar to the pancreas."
"We think this is an important step towards the production of cells for diabetes therapy, both to produce mini-organs for drug testing and insulin-producing cells as spare parts. We show that the pancreatic cells care not only about how you feed them but need to be grown in the right physical environment. We are now trying to adapt this method to human stem cells."