Introduction: Pancreatic islet transplantation has recently emerged as one of the most promising therapeutic approaches for improving glycemic control in type 1 diabetes patients. However, one of the problems with islet transplantation is that it is impossible to culture the isolated islet for extended periods to while recipients are selected, tested and prepared for surgery. To address this problem, we developed the islet preservation solution, and to improve the function of the preservation solution, we added taurine and conducted a preservation experiment. Taurine is antioxidant activity and it is not a classical free radical scavenger. Therefore, its mechanism remains unclear but it controls osmotic pressure. Our hypothesis is that taurine supplementation can improve islet recovery and enhance islet function after low temperature preservation.

Methods: CMRL 1066 medium (Corning) was used as a control group, and a comparison group was prepared some compounds OPTI(Optipharm presevation) solution (with taurine) and OPTI-T solution (without taurine). To confirm the preservation effect of these solutions, we isolated islet from adult Yucatan pig’s pancreas using standard enzymatic digestion (Nordmark) followed by Ficoll purification, these islets were preserved in a humidified tissue culture incubator with preservation solutions and preserved in 4℃ for up to 4 weeks. We compared islet survival in groups of islets. To islet viability and islet functionality, we utilized Glucose Stimulated Insulin Secretion (GSIS) for measuring insulin release, calculated stimulation index (SI) and AO/PI viability staining for during the preservation period.

Results: Highest islet recovery was preserved in the group of pig islets cultured with Taurine as compared to the group of islets hypothermically preserved in standard tissue culture media over the 4 week preservation period (p<0.001 using ANOVA). The porcine islet viability/cell number ratio in the OPTI solution maintained a high survival rate for up to 2 weeks (94%). In contrast, porcine islet in OPTI-T solution and CMRL 1066 supplemented media significantly reduced viability after 1 weeks. OPTI solution (with taurine) was significantly higher than OPTI-T solution (without taurine) and CMRL 1066 during 4 weeks after preservation. Glucose stimulation insulin secretion test was performed for functional analysis. As a result, a level of porcine insulin was higher during 2 weeks in the OPTI solution than OPTI-T solution and CMRL 1066. But after 3 weeks preservation, insulin level in high glucose, significantly decreased. Therefore, the viability and functionality of islets were improved by adding taurine to the developed preservation solution.

Conclusion: Taurine supplementation has been shown to highest islet recovery, viability and insulin secretion level for 2 weeks. Based on this data, we have performed 2 weeks cold storage of isolated islets for current clinical islet transplantation.