豚の肝臓と腎臓の機能 36時間 脳死人間

Pig organs survived 36 hours in a brain‑dead 53‑year‑old man.

Six‑Edit Pig Genome

The donor pig carried six precise edits: three human genes inserted to mitigate clotting risks and three pig genes removed to reduce immunogenicity. Xuyong Sun’s team at the Second Affiliated Hospital of Guangxi Medical University in Nanning, China, performed the transplant on a clinically dead patient whose liver was healthy but kidneys were failing.

Within 19 hours, the pig liver began secreting bile and the patient’s creatinine and urea levels fell to normal, indicating functional kidneys. The pig organs operated as intended for almost five days, a record for multi‑organ xenotransplantation.

Early Rejection Signals

At 36 hours, the team detected early rejection: pig cells in the liver and kidneys were gradually replaced by human cells, and small necrotic zones appeared in the liver. Elevated S100A12⁺ inflammatory cells suggested immune activation. These findings point to a window where targeted immunosuppression could prolong graft survival.

Leonardo Riella of Massachusetts General Hospital noted that while single‑organ xenotransplants are already in clinical trials, adding a second organ dramatically increases operative time and complication risk.

Implications for Future Xenotransplants

Riella and Sun both agree that widespread multi‑organ xenotransplants are not imminent. However, the procedure could benefit patients with combined liver and kidney failure, a scenario where human donor organs are scarce. Sun plans further trials in clinically dead humans and living monkeys, with a focus on viral and bacterial transmission risks.

Wayne Hawthorne of the University of Sydney highlighted that the study demonstrates feasibility, but long‑term graft survival remains uncertain. Targeting S100A12⁺ cells with drugs could become a strategy to mitigate rejection.

The 36‑hour survival milestone suggests that with refined genome editing and immunomodulation, pig organs may one day bridge the donor shortage for complex organ failures.

Source: In a first, scientists transplanted both a pig liver and kidneys into a person who was brain-dead
Domain: scientificamerican.com