An islet-stabilizing implant constructed using a preformed vasculature.

Area of Science:

• Biomedical Engineering
• Regenerative Medicine
• Endocrinology

Background:

• Islet transplantation is a promising treatment for insulin-sensitive diabetes.
• Limited islet survival posttransplantation hinders its clinical success.
• Current strategies require enhancement to improve graft function and longevity.

Purpose of the Study:

• To develop and evaluate a tissue-engineered prevascularized pancreatic encapsulating device (PPED) for improved islet survival.
• To assess the functionality and viability of encapsulated islets in vitro and in vivo.
• To investigate the role of the PPED in supporting intraislet vasculature.

Main Methods:

• Isolated islets were encapsulated in collagen gels within a PPED.
• In vitro studies assessed insulin release and glucose response.
• PPEDs were implanted subcutaneously into immunodeficient mice for survival assessment (7, 14, 28 days).
• Immunohistochemical analysis detected insulin and intraislet endothelial cells.

Main Results:

• Encapsulated islets in collagen gels showed fourfold higher insulin release compared to controls.
• In vitro tests confirmed islet functionality and glucose responsiveness.
• In vivo studies demonstrated sustained insulin localization and intact intraislet endothelial cells at all time points.
• PPED implantation supported islet viability and vascular structure.

Conclusions:

• The PPED enhances pancreatic islet survival posttransplantation.
• The device promotes islet viability and maintains intraislet vasculature, crucial for graft function.
• This tissue-engineered approach offers a promising strategy to overcome limitations in islet transplantation for diabetes.