Korean J Transplant.  2023 Nov;37(Suppl 1):S80. 10.4285/ATW2023.F-6620.

In vivo porcine study of 3D-printed biodegradable paclitaxel-eluting stent for biliary stricture after liver transplantation

• Kim J
• Choi Y
• Suh KS
• Lee KW
• Yi NJ
• Hong SK
• Hong Sy
• Lee JM

• KMID: 2551667
• DOI: http://doi.org/10.4285/ATW2023.F-6620

Abstract

Background
Liver transplantation is the gold standard treatment for end-stage liver disease, but biliary stricture can occur in 25%–30% of cases, leading to complications. Current methods of treating biliary strictures involve endoscopic stent insertion, which can cause restricture, bleeding, and bowel perforation. We aimed to develop a biodegradable stent loaded with paclitaxel that could be inserted during surgery, without requiring separate removal. We conducted an in vivo study in a porcine model to evaluate the safety and efficacy of this stent.
Methods
Fourteen pigs were used and a biodegradable paclitaxel-eluting stent was inserted after duct-to-duct anastomosis. The pigs were divided into four groups based on the type of stent used: no stent group (NS, n=3), bare stent group (BS, n=3), 300 ug paclitaxel stent group (300, n=4), and 900 ug paclitaxel stent group (900, n=4). The pigs were followed up for 3 months after surgery, and computed tomography was performed to confirm the location and degradation of the stent at the 3-month mark. An autopsy was conducted to obtain common bile duct tissue samples, and inflammation and fibrosis thickness were measured under a microscope.
Results
Microscopic examination showed that the inflammation scores for each group were 2.67, 5.33, 3.25, 4.0, respectively (P=0.115). As most tissues had already resolved inflammatory reactions by the 3-month mark, few inflammatory cells were ob-served. Submucosal layer fibrosis was evaluated after Masson-Trichrome staining, and although statistical significance was absent due to the small sample size, the thinnest fibrosis thickness was observed in the 900 ug group (359.08±167.23 um).
Conclusions
Our study demonstrated the safety of paclitaxel-eluting biodegradable biliary stents and their positive effect on fibrosis in an ischemic bile duct porcine model. Further studies are needed to determine their efficacy in actual liver transplantation situations. This biodegradable stent represents a promising approach to overcome the complication barrier associated with biliary stricture after liver transplantation.