Degraded collagenase deteriorates islet viability.

Objective: The utilization of purified enzyme blends consisting of collagenase class I (CI) and II (CII) and neutral protease is an essential step for clinical islet isolation. Previous studies suggested that the use of enzyme lots containing degraded CI reduced islet release from human pancreata. The present study sought to assess the effect of degraded collagenase on islet function in vitro and posttransplantation.

The ratio between collagenase class I and class II influences the efficient islet release from the rat pancreas.

Background: Previous studies indicated different roles of collagenase class I, class II and neutral protease in the enzymatic islet release from pancreatic tissue. Because no information has been available, this study was aimed to investigate the isolation efficiency of different ratios between collagenase class II and I (C-ratio) in the rat pancreas serving as model for the human pancreas without being restricted by the large variability observed in human donors.

Methods: Rat pancreata were digested using a marginal neutral protease activity and 20 PZ-U of purified collagenase classes recombined to create a C-ratio of 0.

Adjustment of the ratio between collagenase class II and I improves islet isolation outcome.

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.

The ratio between class II and class I collagenase determines the amount of neutral protease activity required for efficient islet release from the rat pancreas.

Unlabelled: Previous investigations clearly showed that the successful release of islets from the pancreas is mediated by both neutral protease (NP) and collagenase, consisting of subclasses I and II showing different capacities to cleave islets from the pancreas. Since no informations about the optimal ratio between class II and class I collagenase (II/I-ratio) are available yet, the present study sought to evaluate the efficient range for the II/I-ratio.

Methods: Following intraductal pancreas collagenase distension, rat islets were isolated utilizing 20 PZ-U Serva collagenase NB 1 and 1.

Optimization of neutral protease to collagenase activity ratio for islet of Langerhans isolation.

Aim: The optimal neutral protease to collagenase activity ratio has not been determined for islet isolation. We evaluated a new highly purified collagenase that can be blended with predetermined amounts of neutral protease (NP).

Methods: Islets were isolated from 7 groups of Sprague-Dawley rats.