Diabetes, Vol 40, Issue 7 908-919, Copyright © 1991 by American Diabetes Association
Transplantation of purified islet cells in diabetic rats. I. Standardization of islet cell grafts
DG Pipeleers, M Pipeleers-Marichal, JC Hannaert, M Berghmans, PA In't Veld, J Rozing, M Van de Winkel and W Gepts
Department of Metabolism and Endocrinology, Vrije Universeit Brussel, Belgium.
A standardized procedure was developed for the preparation of rat islet
cell grafts with selected cell number and composition. After collagenase
digestion of pancreases and elutriation of tissue fragments, islets were
isolated and dissociated, and cells were purified by
autofluorescence-activated cell sorting. Approximately 30% of the initial
beta-cell mass was lost during digestion and elimination of small mostly
exocrine particles. Fifty percent was recovered in isolated islet
preparations and 30% in the purified beta-cell suspensions of greater than
95% purity and viability. Sorting according to cellular flavin adenine
dinucleotide content discriminated islet beta-cells from islet endocrine
non-beta-cells, fibroblasts, leukocytes, and exocrine cells. Purified
endocrine islet cell grafts were prepared by aggregating 10(6) pure
beta-cells with or without 8 x 10(5) pure endocrine non-beta-cells. In
contrast to intact islets, the purified aggregates were devoid of
nonendocrine and damaged cells. Intraportal implantation of a pure
beta-cell graft rapidly and permanently normalized the diabetic state of
streptozocin-administered animals. The standardized preparation of purified
beta-cell grafts allows us to address several metabolic and immunological
questions concerning islet cell transplantation in diabetes.