Researchers have engineered small intestinal tissue from human cells, and when placed in mice, the transplants were able to digest and absorb like the real thing. The work, published in the American Journal of Physiology: Gastrointestinal and Liver Physiology this week, could help treat one of the major causes of intestinal failure in premature babies and newborns.
Previous studies by Children’s Hospital Los Angeles (CHLA) researchers showed how tissue-engineered small intestine (TESI) could be generated from taking human small intestine donor tissue and then implanting it into immunocompromised mice. But only basic components of the intestine were replicated. To be useful, the TESI must form a healthy barrier while still absorbing nutrients or exchanging electrolytes.
Now, CHLA’s Tracy Grikscheit and colleagues have found that mouse TESI is very similar to the TESI derived from human cells—and that both contain key building blocks such as the precursors (both stem and progenitor cells) that will go on to regenerate a living tissue replacement intestine. These cells are found within the engineered tissue near other specialized cells known to be necessary for healthy, fully functioning intestine.
After taking a small sample of both mouse and human intestine, grinding it up, and soaking it in a digestive enzyme solution, New Scientist explains, the team placed the mixture on a polymer scaffold and implanted into the abdominal cavity of an immunodeficient mouse. Four weeks later, the transplanted scaffolds seeded with human gut tissue had grown several features typical of our small intestine: mucus-packed goblet cells and specialized cells that release gastrointestinal hormones, New Scientist reports. Furthermore, the TESI could break complex sugars down into simple glucose.
“We have shown that we can grow tissue-engineered small intestine that is more complex than other stem cell or progenitor cell models that are currently used to study intestinal regeneration and disease, and proven it to be fully functional as it develops from human cells,” Grikscheit says in a news release. “Demonstrating the functional capacity of this tissue-engineered intestine is a necessary milestone on our path toward one day helping patients with intestinal failure.”