Islet isolation and autotransplantation in pigs

Area of Science:

• Transplantation Biology
• Endocrinology
• Surgical Research

Background:

• Porcine pancreatic islets are crucial for diabetes research, but functional integrity after isolation and transplantation requires further validation.
• Previous studies have focused on isolation and purification, yet comprehensive assessment of post-transplant metabolic function in pigs is limited.

Purpose of the Study:

• To investigate the feasibility, technical challenges, and post-transplant metabolic function of islet transplantation in pigs.
• To evaluate islet preparation, transplantation techniques (intraportal vs. intrasplenic), and associated complications.

Main Methods:

• Utilized intraductal collagenase perfusion for islet isolation in 27 landrace and 8 minipigs.
• Transplanted islets via intraportal or intrasplenic routes, with some preparations purified using dextran gradients.
• Monitored islet yield, portal vein pressure, complications, and graft function, including intravenous glucose tolerance tests.

Main Results:

• Successful islet isolation and transplantation were achieved, with varying rates of normoglycemia (25-50%) depending on pig breed and transplant site.
• Portal vein thrombosis occurred in 4 animals, associated with significantly elevated portal pressure.
• Landrace pigs exhibited higher perioperative mortality (11/27) compared to minipigs (0/8).

Conclusions:

• Islet transplantation is a feasible procedure in both landrace and minipigs, with demonstrable improvements in glucose metabolism and longevity in normoglycemic recipients.
• The landrace pig model presents higher susceptibility to perioperative mortality, suggesting areas for procedural optimization.
• This study provides critical data on the functional outcomes and challenges of porcine islet transplantation, advancing its potential for diabetes research.