Scientists from Children’s Hospital Los Angeles have discovered a method for growing functional, human intestinal tissue inside a laboratory, the findings of which have been published in a study in the American Journal of Physiology: GI & Liver.

With the discovery, the team can move forward in their exploration of short bowel syndrome (SBS), a devastating condition involving an undersized small intestine. People with SBS face a host of health challenges, including malnutrition and the inability to feed themselves. Unfortunately, the invasive go-to method for treating SBS, intestinal transplantation, comes with its own set of drawbacks. The new tissue-engineered intestines may offer patients a therapeutic alternative.

"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," said senior author of the study and assistant professor of surgery at the University of Southern California, Dr. Tracy Grikscheit, in a statement.

The work builds on a vast network of stem-cell-based approaches to organ development. In April of last year, scientists successfully built a lab-grown vagina for several teenage girls who suffered from underdeveloped reproductive organs, due to a condition known as Mayer-Rokitansky-Hauser syndrome. Within the last two years, stem cells have also been used to grow human stomachs, blood vessels, bones, corneas, sperm, skin, and have been used in multiple trials to quell the effects of cancer and diseases of the nervous system.

Premature babies and newborns with congenital deficiencies in their intestines stand the most to gain from the tissue-engineered small intestine, or TESI. Without intervention, they risk developing a disease called necrotizing enterocolitis, or NEC. It occurs most often in babies who weigh less than 3 pounds, 5 ounces, at roughly a 10-percent incidence rate. The disease forces intravenous feeding, due to a lack of intestinal length, and it may also produce liver damage. Approximately one quarter of babies with NEC will die from it.

TESI hopes to change that. The new structures mimic the original version of the organ in their replication of the mucosal lining, the ability to absorb sugars, and even in their so-called ultrastructural components, which let the lab-grown intestine maintain cellular connections. Prior work in 2011 showed mouse models could serve as reliable hosts for the human tissue. Now, the team says, TESI contains the important building blocks of progenitor and stem cells that are necessary to keep regenerating the replacement tissue.

"Demonstrating the functional capacity of this tissue-engineered intestine is a necessary milestone on our path toward one day helping patients with intestinal failure," Grikscheit said.

Source: Grant C, Salvador G, Sala F, et al. Human and Mouse Tissue-Engineered Small Intestine Both Demonstrate Digestive And Absorptive Function. American Journal of Physiology: GI & Liver. 2015.