Digestive Disease Week (DDW) 2015 Luca Cicalese, MD –
What if people with seriously diseased or damaged intestines could use their own stem cells to grow new “bio-artificial” intestinal tissue to replace parts of their bowels?
It certainly would be a life-changing and life-saving discovery for countless children who are born with congenital conditions, such as short bowel syndrome, as well as adults suffering from injuries, tumors, or painful intestinal ailments such as Crohn disease.
After nearly 10 years of work, my colleagues and I believe that we are on the verge of a major breakthrough. We have demonstrated for the first time the ability to create fully functioning “bio-artificial” tissue grown from intestinal stem cells in the bowels of laboratory rats. Our team from the University of Texas Medical Branch at Galveston presented our work to the scientific community at this year’s Digestive Disease Week, the world’s largest gathering of physicians and researchers in gastroenterology, hepatology, endoscopy, and gastrointestinal surgery.
Other attempted cures for diseased or damaged intestines have been problematic. Intravenous feeding, although initially effective, is associated with severe complications and poor quality of life. Transplantation is potentially curative but remains challenging because of a shortage of donors, high infection rates, and potent immunosuppression due to the danger of organ rejection.
Initially, we were able to create a piece of bio-artificial intestine by detaching a segment of intestine from a pig and removing all of its cells, creating a decellularized biologic scaffold. This matrix of collagen fibers was created for implanting intestinal cells from rats—and it grew into a piece of intestinal tissue. And, because our tissue scaffold came from something that already existed in nature, it was not subject to rejection by the body.
However, this success was only superficial. We created new tissue, but it was artificial and nonfunctional.
In our current experiment, we demonstrated that the newly formed intestinal segments that were transplanted into 20 rats have become fully functioning. After 12 weeks of growth, we tested the new intestinal tissue with urine and blood samples and showed that it was absorbing nutrients as effectively as normal intestinal tissue.
We are planning up to 3 years of work on larger animals, after which we hope to be ready for human clinical trials.
If we can eventually use this technique in humans, it could eliminate the need for intravenous feeding, surgery, or transplants. And, if we can successfully create portions of new human intestine, the potential to cure diseases by regenerating new organ tissue could open up countless new fields of cure.