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Updated: Jun 20, 2026
09:01
Intraportal Transplantation of Pancreatic Islets in Mouse Model
Published on: May 5, 2018
Impaired proinsulin processing is a characteristic of transplanted islets
A M Klimek1, G Soukhatcheva, D M Thompson
1Department of Pathology and Laboratory Medicine, British Columbia Children's Hospital, Child and Family Research Institute, University of British Columbia, Vancouver, BC, Canada.
Summary
Islet transplant recipients show impaired proinsulin processing, similar to type 2 diabetes. This involves higher total proinsulin and altered ratios of proinsulin to insulin and C-peptide, indicating a potential post-transplant complication.
Area of Science:
- Endocrinology
- Transplantation Immunology
- Metabolic Disorders
Background:
- Proinsulin processing is crucial for regulated insulin secretion.
- Defective proinsulin processing is a hallmark of type 2 diabetes.
- Islet transplantation aims to restore endogenous insulin production.
Purpose of the Study:
- To investigate proinsulin processing defects in islet transplant recipients.
- To compare islet allo- and autotransplant recipients with healthy controls.
- To assess the impact of islet transplantation on proinsulin processing over time.
Main Methods:
- Serum samples from islet transplant recipients and healthy controls were analyzed.
- Immunoassays measured insulin (I), total proinsulin (TP), and C-peptide (CP).
- Ratios of TP/TP+I and TP/CP were calculated to assess processing efficiency.
Main Results:
- Islet allotransplant recipients had elevated TP levels compared to controls.
- Both allo- and autotransplant recipients showed significantly higher TP/TP+I and TP/CP ratios.
- TP/CP ratios increased post-transplant and were higher in recipients with lower islet graft mass.
Conclusions:
- Islet transplant recipients exhibit proinsulin processing defects.
- These defects resemble those seen in type 2 diabetes.
- Impaired proinsulin processing may be a consequence of islet transplantation or graft dysfunction.
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