Preparation of Viable islet Cells from Dogs by a New Method

Abstract

A new method for the preparation of viable islet cells from the normal dog pancreas is described, based on the perfusion of the pancreatic duct with collagenase. Exposure of the acinar tissue to the highest concen-trations of collagenase results in improved islet yield with decreased acinar contamination. After the selec-tive digestion of the gland by ductal perfusion, me-chanical dissociation liberates single cells and clumps. Analysis of the procedure by insulin yield and amylase attrition indicates a 57 % B-cell recovery and a sixfold enrichment in B-cell concentration. The cells have been transplanted as autografts into dogs after pancreatectomy. In 5 of 7 transplanted dogs, normo-glycemia was achieved postoperatively. DIABETES 30:455-458, May 1981. There has been a great deal of interest in the trans-plantation of islets of Langerhans for diabetic con-trol. The isolation of islets has become a standardtechnique in many laboratories,1"4 and successful transplantation of isolated islets has been accomplished in rats.5"7 However, the recovery of islets in rats is sufficiently low that tissue from several donors is required to achieve normal carbohydrate metabolism in a single recipient.5"7 In large animals (and certainly humans) which have a more or-ganized and fibrous pancreas, the islet isolation techniques give an even poorer yield!4-8-9 The standard collagenase digestion techniques involve ductal distention, mincing, and incubation of the pancreatic fragments in collagenase. Ductal distention and disruption expose interlobular pianes to collagenase, which digests acinar and islet components indiscriminately.10 Mincing of the pancreas causes a 50 % loss of tissue insulin.11 Incuba-tion of the chopped pancreas in collagenase destroys mor