Engineered Esophagus Rebuilds Missing Organ Segment in Pig Models
Children born without a functioning esophagus may someday get a new one grown from their own cells and a pig-derived scaffold. Scientists at Great Ormond Street Hospital and University College London have demonstrated the concept in pigs — a meaningful step toward a clinical reality that has so far remained out of reach.
The team published their results in Nature Biotechnology on Friday. The approach involves taking a pig esophagus, stripping out all its cells to leave just the support structure, then repopulating it with muscle cells and fibroblasts taken from the recipient animal. The repopulated scaffold is kept in a bioreactor for a week before implantation. In eight recipient minipigs, all survived the critical first 30 days. By six months, the engineered organs had developed functional muscle, nerves, and blood vessels — allowing the animals to eat normally.
The clinical motivation is clear. Children born with long-gap esophageal atresia have a gap too wide to close immediately after birth. The standard options — repositioning the stomach or intestine — work but carry significant complications. A tissue-engineered esophagus using the child own cells would, in theory, integrate without rejection and grow with the patient, eliminating the need for lifelong immunosuppression.
Marco Pellegrini, senior researcher at the UCL GOS Institute of Child Health and a co-lead on the study, put it plainly: the technology could build a child a new esophagus using their own cells, collected during a surgery they are already having, combined with a ready-prepared scaffold from pig tissue.
But the path from pig to human is not short. Experts not involved in the research are flagging a critical gap: there is no evidence that the construct can accommodate somatic growth. Professor Dusko Ilic of King College London, who commented via the Science Media Centre, noted that the study shows remodeling and functional integration over six months, but the graft is implanted at a fixed length. Whether it can elongate and scale as the animal — or child — grows remains unstudied.
This is not a trivial concern, Ilic said. Demonstrating true growth would require long-term studies with direct measurements of graft expansion and evidence of a self-renewing progenitor niche supporting coordinated tissue development. He added that persistent fibrosis and stricture formation in the animal model suggest the current construct behaves as a remodeling scaffold rather than a dynamically growing tissue.
The team is now working to generate longer grafts, standardize manufacturing, and carry out further safety testing. They hope to begin a first-in-human research trial within five years. That timeline is reasonable for early-phase work but means the intervention is not close to clinical use for the children who need it now.
The bigger context is that regenerative medicine has produced remarkable proof-of-concept demonstrations for complex organs — but has consistently hit the same wall when trying to move from animal models to pediatric use. The esophagus is hollow, mechanically complex, and must function from the day of implantation while also growing with the patient. Engineering something that can do both is the unsolved problem.
What this study demonstrates is that the scaffold-plus-cells approach can produce a functional organ in a large animal. That is real progress. The remaining questions — growth, scale-up, long-term safety — are the difference between a promising laboratory result and a therapy that can be deployed in a hospital.
Sources: GEN News (March 20, 2026) | Nature Biotechnology (DOI: 10.1038/s41587-026-03043-1) | Science Media Centre expert reaction