P-247

Subcutaneous transplantation may not be an appropriate approach for the islets embedded in the collagen gel scaffolds

J. Xu¹, G. Miao¹, Y. Zhao², J. Wei¹

¹ Department of General Surgery, Beijing Hospital, Beijing, China; ² Institute of Geriatric Medicine, Ministry of Health, Beijing, China

Background: Synthetic extracellular matrix (ECM) has been demonstrated efficient in preserving better function of transplanted islets. In this study, we tried to determine whether subcutaneous transplantation, which may be a more convenient and easier procedure, may achieve normoglycemia using a mouse model.

Methods: In vitro test was done to make sure that embedded islets survived better than the non-embedded islets with morphologic observation and western blotting. Streptozotocin induced diabetic mice (BALB/c) were transplanted with ECM-embedded syngeneic islets via the subcutaneous (SC) and subrenal capsule (SRC) routes. Data were taken between SC (n=5) and SRC (n=6) groups: 1) Mean blood glucose level at various points from pre-transplantation day to postoperative day 14, and 2) Immunohistochemistry staining for insulin in the transplant grafts on the post-transplant day 14.

Results: Islets transplanted with ECM gel retained better stucture and developed a functional islet vasculature. Western blotting demonstrated that more Caspase-3 was expressed in the non-embedded islets, which indicates more islet cells were undergoing apoptosis. On the first day after transplantation, the glucose level was significantly decreased in the SRC group compared with SC group(383.33±44.50 to 80.67±16.85 v.s.414.00±92.33 to 278.28±121.80, P<0.05). The glucose levels were maintained better in the SRC group than SC group during the 14 days. Immunohistochemistry staining for insulin showed fewer islets were found in the SC group.

Conclusion: Embedded islets with ECM gel functioned better than non-embedded ones in vitro. However, subcutaneous route may not be an ideal site for islet transplantation.

P-247

Subcutaneous transplantation may not be an appropriate approach for the islets embedded in the collagen gel scaffolds

J. Xu¹, G. Miao¹, Y. Zhao², J. Wei¹

¹ Department of General Surgery, Beijing Hospital, Beijing, China; ² Institute of Geriatric Medicine, Ministry of Health, Beijing, China

Background: Synthetic extracellular matrix (ECM) has been demonstrated efficient in preserving better function of transplanted islets. In this study, we tried to determine whether subcutaneous transplantation, which may be a more convenient and easier procedure, may achieve normoglycemia using a mouse model.

Methods: In vitro test was done to make sure that embedded islets survived better than the non-embedded islets with morphologic observation and western blotting. Streptozotocin induced diabetic mice (BALB/c) were transplanted with ECM-embedded syngeneic islets via the subcutaneous (SC) and subrenal capsule (SRC) routes. Data were taken between SC (n=5) and SRC (n=6) groups: 1) Mean blood glucose level at various points from pre-transplantation day to postoperative day 14, and 2) Immunohistochemistry staining for insulin in the transplant grafts on the post-transplant day 14.

Results: Islets transplanted with ECM gel retained better stucture and developed a functional islet vasculature. Western blotting demonstrated that more Caspase-3 was expressed in the non-embedded islets, which indicates more islet cells were undergoing apoptosis. On the first day after transplantation, the glucose level was significantly decreased in the SRC group compared with SC group(383.33±44.50 to 80.67±16.85 v.s.414.00±92.33 to 278.28±121.80, P<0.05). The glucose levels were maintained better in the SRC group than SC group during the 14 days. Immunohistochemistry staining for insulin showed fewer islets were found in the SC group.

Conclusion: Embedded islets with ECM gel functioned better than non-embedded ones in vitro. However, subcutaneous route may not be an ideal site for islet transplantation.