Related Experiment Video
Updated: Aug 14, 2026
A Simple High Efficiency Protocol for Pancreatic Islet Isolation from Mice
Published on: August 30, 2019
Adjustment of the ratio between collagenase class II and I improves islet isolation outcome
D Brandhorst1, S Huettler, A Alt
1Third Medical Department, University Hospital, Rodthohl 6, 35385 Giessen, Germany. Daniel.Brandhorst@innere.med.uni-giessen.de
Background:
Previous studies have clarified the distinct roles of collagenase class I (ccI) and class II (ccII) in enzymatic release of islets from pancreatic tissue. The present study sought to enhance the limited knowledge about the optimal ratio between collagenase classes.
Methods:
Rat islets were isolated utilizing 0.4 DMC-U of neutral protease and 20 PZ-U of fractionated NB-1 collagenase recombined to obtain a ccII/I ratio of 0.5, 1.0, and 1.5. Quality control included assessment of yield (islet equivalents), trypan-blue exclusion, insulin release during static glucose incubation, and transplant function in diabetic nude mice. Data are expressed as mean values +/- SEM.
Results:
Digestion time was only minimally influenced by different ccII/I ratios. The highest islet yield (P < .05) was obtained using a ccII/I ratio of 1.0. Purity and glucose stimulation index were only marginally affected by different ccII/I ratios. A significant loss of islet viability after 24-hour culture (P < .05) was observed only in islets isolated by means of a ccII/I ratio of 0.5 and 1.5 but not 1.0. Transplantation into diabetic nude mice revealed sustained islet graft function in all experimental groups.
Conclusions:
The present study indicates that the ratio between ccII and ccI is of significant relevance for optimizing islet yield and viability.
