Comparison of different collagenases in islet isolation from Chinese organ donors

Objective To retrospectively compare the efficacy of Serva NB1 collagenase with Vitacyte GOLD collagenase on islet isolation of pancreas. Methods All the human pancreata were obtained from Chinese organ donors. In GMP laboratory, the pancreata were trimmed and distended with Serva NB1 collagenase (Serva NB1, n =12) or Vitacyte GOLD collagenase (Vitacyte GOLD, n =5) and digested according to a modified Ricordi semi-automatic protocol, and the digestion duration was recorded. The digested islets were then collected and washed, followed by the continuous density purification in a Cobe 2991 cell separator. The islet yield, purity, viability and glucose-stimulated insulin release (GSI) were determined each time after purification. Quantity and quality of isolated islets were determined by digestion efficacy. Results The digestion duration in Vitacyte GOLD collagenase group was significantly shorter than in Serva NB1 collagenase group to achieve the same digestion endpoint ( P <0.05). The islets yields of different sizes were variable between the two groups. The Vitacyte GOLD collagenase digestion produced more islets with a diameter range of 50-100 μm than the ServaNB1 collagenase digestion ( P <0.05), but the latter yielded more islets with a diameter range of 251-300 μm and 301-350 μm ( P <0.05). There was no significant difference in total islets yields, viability, and GSI between two collagenase digestions ( P >0.05). Conclusion Both Vitacyte GOLD collagenase and Serva NB1 collagenase can be used for the clinical islet isolation in China.