Implantable vascularized endocrine constructs for clinically scalable insulin delivery

Area of Science:

• Regenerative Medicine
• Biomaterials Science
• Endocrinology

Background:

• Extrahepatic islet transplantation is promising but limited by poor vascularization and microenvironment support.
• Current methods face challenges in achieving long-term islet survival and function post-transplantation.

Purpose of the Study:

• To engineer vascularized endocrine constructs (VECs) for improved extrahepatic islet transplantation.
• To evaluate the efficacy of a novel amniotic membrane hydrogel (Amniogel) scaffold in supporting islet and endothelial cell co-culture.

Main Methods:

• Coencapsulation of pancreatic islets and human blood outgrowth endothelial cells within a GMP-compliant amniotic membrane hydrogel (Amniogel).
• Assessment of endothelial self-assembly, islet viability, function, and vascularization after subcutaneous implantation in diabetic mouse models.
• Evaluation of Amniogel's immunomodulatory properties in vitro.

Main Results:

• Engineered VECs demonstrated enhanced islet viability, function, and restored glucose-responsive insulin secretion.
• Implanted VECs successfully anastomosed with host vasculature, leading to sustained normoglycemia in diabetic mice.
• Amniogel exhibited concentration-dependent inhibition of cytotoxic T cell migration, suggesting immune-protective properties.

Conclusions:

• The developed VECs using Amniogel offer a clinically relevant strategy for enhanced vascularization and immune modulation in islet transplantation.
• This approach represents a significant advancement toward durable beta-cell replacement therapies for type 1 diabetes.
• Amniogel serves as a supportive and protective scaffold, overcoming key limitations in current islet transplantation protocols.