Improved human islet isolation by a tube method for collagenase infusion

Background. Collagenase infusion into the pancreatic duct is an essential s tep in human islet isolation. We developed a new method for ductal canulati on and collagenese infusion. Methods. A total of 53 pancreata were divided into two groups: group 1 (n=2 3), the new tube method, and group 2 (n=30), the standard angiocatheter met hod. In group I, a polyethylene tube was inserted into the duct and pushed to the tail. The tail was first expanded, followed by expansion of the body and then the head, by pulling out the tube, Results. Total islet number and number/g pancreas (mean+/-SE) were signific antly higher in group 1 (481,123+/-43,218 and 8,010+/-722) (mean+/-SE) than in group 2 (300,974+/-35,122 and 5,090+/-515, P<0.01). Total islet equival ent number and islet equivalent number per gram pancreas were also signific antly higher in group 1 (319,176+/-39,354 and 5,455+/-652) than in group 2 (202,022+/-23,331 and 3,722+/-468, P<0.04). Islet purity and fragmentation showed no differences between the groups. Conclusions. The tube method improved islet yields. We recommended this met hod for human islet isolation.