A new dimension to intestinal surgery

Long considered one of the worst abdominal injuries, intestines damaged by trauma or illness are almost impossible to heal, and the injuries are fatal under certain circumstances. New technology may change that: 3D printing intestines from a subject’s own cells is fast approaching commercial viability. And John Geibel, DSc, MD, MS, FW ’88, professor of surgery (gastrointestinal), of cellular and molecular physiology, vice chair of the Department of Surgery, and director of surgical research, is at the forefront of efforts to bring 3D-printed intestines to market.

“Imagine, God forbid, you’ve been stabbed, or shot, as often happens during war, or you develop some condition that damages your intestines [radiation treatment, traumatic injury, or genetic abnormality that reduces functional intestine]. Soon, we’ll be able to fix that,” said Geibel.

Fixing pieces or lengths of intestine using 3D printing was something Geibel had considered, but it wasn’t until he partnered with a company called Organovo that he had the equipment to begin trials. Initial testing was promising, with lengths of intestine holding up well to volume and pressure, so he decided to push the limits, and developed a procedure capable of printing intestines even faster.

“The key to commercial viability with this process is being able to make durable pieces of intestine that won’t rupture, in a short enough timeframe that the patient can benefit from it quickly. We think we have such a procedure,” said Geibel.

Drawn to the intestine partly because of his surgical focus on gastroenterology, Geibel said that focusing on printing this particular organ provides another advantage to people looking to bring it online quickly as a therapeutic option: its relative simplicity.

“The heart has seven cell types with multiple chambers, multiple valves. The kidney has 26 different cell types and 2 million nephrons, not counting connective tissue and vasculature. The intestines have seven cell types,” Geibel said. “Furthermore, if you implant a piece of intestine grown outside the body, that intestine will actually integrate into the rest of the system, so it can absorb nutrients and be more than just a length of flexible tubing.”

The absorption of nutrients is one of the key difficulties for people suffering from diseases, conditions, or injuries that affect the intestine. Initial trials have been very promising, and 3D-printed intestinal sections that have been implanted to plug holes or cuts made in healthy intestines in a laboratory setting have been successful in animal models.

Although there are troubling technical aspects to forming viable lengths of intestine, Geibel feels that his technique addresses all concerns. Now, he’s working with ways to print the intestine faster while also strengthening the printed organ so that it can endure the vast amounts of liquid, salts, nutrients, and waste products it will be expected to carry. The final step will be to test it in people. Geibel is eager to advance to this point, and to give people who are suffering from life-altering health complications hope for a viable replacement that can restore functionality to damaged tissue.