Study of isolation efficiency of new islet isolation solution for mouse islets / 器官移植

ABSTRACT

Objective To investigate the isolation and protective effect of a new islet purification solution (IPS)-Optiprep solution on the islet in mouse models. Methods The digested pancreatic islets were divided into the IPS and UW groups according to the islet volume. The pancreatic islets were isolated by the continuous gradient density centrifugation using IPS-Optiprep or UW-Optiprep solutions. The purification efficiency and isolated islet activity of purification solution were compared between two groups. The diabetic mouse models were successfully induced and randomly assigned into three groups. In the experimental group (n=10), the mice received pancreatic islet transplantation using islets isolated and purified by the IPS-Optiprep solution. In the control group (n=10), the mice underwent pancreatic islet transplantation using islets isolated and purified by the UW-Optiprep solution. In the sham surgery group (n=5), the mice merely underwent surgery without pancreatic islet transplantation. Postoperative blood glucose levels were detected and compared among three groups. The blood glucose levels of intraperitoneal glucose tolerance test at postoperative 21 d were statistically compared between the experimental and control groups. The cost of the preparation of two isolation solutions was also compared. Results Compared with the UW group, the islet equivalent (IEQ), islet purity, recovery rate and islet integrity were significantly higher in the IPS group. Islet morphological observation revealed that the islet membrane was complete and the islet diameter in the IPS group was considerably larger than that in the UW group. The activity of purified islets in the UW group was significantly higher than that in the IPS group [(88±5)% vs. (84±3)%, P<0.01]. Compared with the UW-Optiprep solution, identical in vivo islet function was obtained in the IPS-Optiprep solution.The cost of IPS-Optiprep solution was significantly less than that of the UW-Optiprep solution. Conclusions The new IPS-Optiprep solution yields higher islet isolation efficiency, purification, integrity and recovery rate and significantly reduces the purification cost compared with the UW-Optiprep solution. Nevertheless, IPS-Optiprep solution exerts a less protective effect on the activity of islet cells, which is probably correlated with the high islet integrity and the endotoxin in the IPS-Optiprep solution.