Large-Scale Purification of Human Islets Utilizing Discontinuous Albumin Gradient on IBM 2991 Cell Separator

A new method is described for the large-scale purification of human pancreatic islets with a discontinuous gradient of bovine serum albumin formed on an IBM 2991 cell separator. Fifteen human pancreases were processed, and after density-gradient centrifugation, a mean of 2643 islets/ml pancreatic digest were recovered with a mean purity of 63% and contained in 430 μm mean vol. Viability of gradient-isolated islets was compared with that of non-densitygradient islets (handpicked) and showed no difference in function. This technique allows isolation of intact, viable human islets of Langerhans of sufficient purity for potential human transplantation.