This sort of regenerative medicine research will in the long term help to decipher the signaling produced by different sorts of stem cells in different tissues. Researchers will ultimately remove the need for cell transplants to boost regenerative capabilities and rebuild damaged organs, and produce these effects by controlling existing cell populations:
Amniotic fluid stem (AFS) cells were harvested from rodent amniotic fluid and given to rats with necrotizing enterocolitis (NEC). Other rats with the same condition were given bone marrow stem cells taken from their femurs, or fed as normal with no treatment, to compare the clinical outcomes of different treatments. NEC-affected rats injected with AFS cells showed significantly higher survival rates a week after being treated, compared to the other two groups. Inspection of their intestines, including with micro magnetic resonance imaging (MRI), showed the inflammation to be significantly reduced, with fewer dead cells, greater self-renewal of the gut tissue and better overall intestinal function.
While bone marrow stem cells have been known to help reverse colonic damage in irritable bowel disease by regenerating tissue, the beneficial effects from stem cell therapy in NEC appear to work via a different mechanism. Following their injection into the gut, the AFS cells moved into the intestinal villi - the small, finger-like projections that protrude from the lining of the intestinal wall and pass nutrients from the intestine into the blood. However, rather than directly repairing the damaged tissue, the AFS cells appear to have released specific growth factors that acted on progenitor cells in the gut which in turn, reduced the inflammation and triggered the formation of new villi and other tissues.
"Stem cells are well known to have anti-inflammatory effects, but this is the first time we have shown that amniotic fluid stem cells can repair damage in the intestines. [Although] amniotic fluid stem cells have a more limited capacity to develop into different cell types than those from the embryo, they nevertheless show promise for many parts of the body including the liver, muscle and nervous system."