Regeneration of the Human Intrahepatic Nervous System in Living Donor Liver Transplantation Recipients

Nerve fibers in the liver help to regulate blood flow and metabolism. They spread from the porta hepatis along the Glissonean sheath (GS) to the hepatocytes and the surrounding areas. In liver transplants, these nerves are completely resected, but their regeneration is not well known. This study examined how and when these nerves regenerate following living donor liver transplantation (LDLT).

The study included 7 patients who underwent LDLT, with follow-up periods ranging from 5 to 27 years. Six patients underwent follow-up biopsies, and 1 patient underwent whole-liver re-transplantation. A biopsy specimen obtained during transplantation was used as the control. Nerve regeneration was assessed using synaptophysin immunohistological staining to detect nerve fibers.

In 6 cases, nerve fibers disappeared soon after the transplant and were not observed for months or years. In three cases with follow-up periods exceeding 15 years, nerve fibers were observed around the GS only after more than 15 years had elapsed. In the re-transplanted liver, thick nerve fibers grew around the large GS, but thin fibers did not appear around the smaller GS or within liver lobules.

Nerve fibers from donor liver diminished immediately after LDLT. They grew mainly around the medium to large GS, with little or no growth within the lobules.