Even though a stem population has been identified and studied in the gastrointestinal tract, Wellcome Trust Researchers have identified a new source of GI-based stem cells that have the ability to repair damage from inflammatory bowel disease when transplanted into mice. This work comes to us from the Wellcome Trust-Medical Research Council Cambridge Stem Cell Institute at the University of Cambridge and BRIC at the University of Copenhagen, Denmark. This work could translate into patient-specific regenerative therapies for inflammatory bowel diseases such as ulcerative colitis.
Adult tissues contain specialized stem cells populations that maintain individual tissues and organs. Adult stem cells tend to be restricted to their tissue of origin and also tend to have the ability to differentiate into a limited subset of adult cell types. Stem cells found in the gut, for example, typically can typically contribute to the replenishment of the gut whereas stem cells in the skin will only contribute to maintenance of the skin.
When examining the developing intestinal tissue in a mouse embryos, Kim Jensen and her team discovered stem cell population hat were quite different from those adult stem cells that have been described in the gut. These cells actively divided and also could be grown in the laboratory over long periods of time without undergoing differentiation into mature cells. Under specific culture conditions, however, these cells could be induced to differentiate into mature intestinal tissue.
When these cells were transplanted into mice that suffered from an inflammatory bowel disease, The implanted stem cell attached to the damaged areas within the intestine, and began to integrate into the existing tissue, within three hours of implantation.
The lead researcher in this study, Dr. Kim Jensen, a Wellcome Trust researcher and Lundbeck foundation fellow, said: “We found that the cells formed a living plaster over the damaged gut. They seemed to respond to the environment they had been placed in and matured accordingly to repair the damage.
“One of the risks of stem cell transplants like this is that the cells will continue to expand and form a tumour, but we didn’t see any evidence of that with this immature stem cell population from the gut.”
Cells with similar characteristics were isolated from both mice and humans. Jensen’s team also generated similar cells by reprogramming adult human cells to make induced Pluripotent Stem Cells (iPSCs) that were also grown under the appropriate culture conditions.
“We’ve identified a source of gut stem cells that can be easily expanded in the laboratory, which could have huge implications for treating human inflammatory bowel diseases. The next step will be to see whether the human cells behave in the same way in the mouse transplant system and then we can consider investigating their use in patients,” added Dr Jensen.