Ductal injection of preservation solution increases islet yields in islet isolation and improves islet graft function.

For islet transplantation, it is important to obtain an available islet mass adequate for diabetes reversal from a single donor pancreas. A recent report demonstrated that the use of M-Kyoto solution instead of UW solution improved islet yields in the two-layer method for pancreas preservation. The present study investigated whether the ductal injection of a large volume of preservation solution (UW and M-Kyoto solution) before pancreas storage improves islet yields. Islet yield both before and after purification was significantly higher in the ductal injection (+) group compared with the ductal injection (-) group. TUNEL-positive cells in the ductal injection (+) group were significantly decreased in comparison to the ductal injection (-) group. The ductal injection of preservation solution increased the ATP level in the pancreas tissue and reduced trypsin activity during the digestion step. Annexin V and PI assays showed that the ductal injection prevents islet apoptosis. In a transplant model, the ductal injection improved islet graft function. These findings suggest that the ductal injection of preservation solution, especially the M-Kyoto solution, leads to improved outcomes for pancreatic islet transplantation. Based on these data, this technique is now used for clinical islet transplantation from non-heart-beating donor pancreata or living donor pancreas.