Insulin secretion from pancreatic islets in fibrin glue clots at different fibrinogen and thrombin concentrations

Abstract

Background: Fibrin glue has proven to be a good delivery system for cell transplantation but the factors that influence the fibrin-cell relationships are not well understood. The purpose of this study was to assess the effect of different concentrations of fibrin glue components (thrombin and fibrinogen) on the function of pancreatic islets.

Method: Islets were isolated from rat pancreata and combined with 6 different fibrin glue formulations. Each islet sample was incubated sequentially with RPMI containing low and high glucose, and culture supernatants were harvested for insulin determination using enzyme-linked immunosorbent assay (ELISA).

Results: The control group (no fibrin glue) and group 3 (with thrombin 50 U/mL and fibrinogen 10 mg/mL) had the highest insulin secretion in response to glucose stimulation. These were followed by groups 5 and 4 with 2.6 and 1.8 stimulation indexes, respectively. Group 2 (with thrombin 50 U/mL and fibrinogen 5 mg/mL) and group 6 (commercial kit with thrombin 250 U/mL and fibrinogen 75-115 mg/mL) had the lowest insulin response after glucose stimulation.

Conclusion: This study demonstrates that different fibrin glue formulations significantly impact pancreatic islets function. In the future, when using fibrin glue as a carrier for pancreatic islet transplantation, lower concentrations of fibrinogen and thrombin are recommended to obtain more viable and functional grafts.