title: Improvement of collagenase distribution with the ductal preservation for human islet isolation.
abstract: A delivery of collagenase at the islet-exocrine interface is crucial for successful human islet isolation. In this study, we investigated how the ductal preservation method at the procurement site affected collagenase distribution. At first, we analyzed human islet isolation data among groups using Serva collagenase with or without ductal injection (DI) or using new Liberase MTF with DI. Then, to assess the distribution of collagenase, human pancreata were classified into two groups: without DI (no DI, n = 5) and with DI at the procurement site (DI, n = 5). Collagenase with 1% marking dye was perfused in the same manner as in our clinical isolation. The distension of the pancreas and the microscopic distribution of the dyed collagenase in pancreas sections were examined. For microscopic analysis, islets were counted and classified into three criteria: unreached, dye didn't reach the islet surface; surface, dye resided on the surface of the islet but not inside; and inside, dye was found inside the islet. As a result, DI groups substantially improved islet yields. In addition, Liberase MTF with DI significantly improved efficacy of pancreas digestion. All pancreata were well distended macroscopically. However, microscopically, the majority of islets in the no DI group were untouched by the dyed collagenase. Ductal preservation substantially improved dyed collagenase delivery on the surface of islets. In conclusion, delivery of collagenase on the surface of islets was unexpectedly insufficient without DI, which was substantially improved by DI. Thus, ductal preservation is a potent method to improve collagenase delivery and islet yields.
authors.affiliation: Baylor University Medical Center at Dallas, Dallas, TX USA.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Shimoda
authors.forename: Takeshi
authors.initials: T
authors.lastname: Itoh
authors.forename: Koji
authors.initials: K
authors.lastname: Sugimoto
authors.forename: Shuichi
authors.initials: S
authors.lastname: Iwahashi
authors.forename: Morihito
authors.initials: M
authors.lastname: Takita
authors.forename: Daisuke
authors.initials: D
authors.lastname: Chujo
authors.forename: Jeffery A
authors.initials: JA
authors.lastname: Sorelle
authors.forename: Bashoo
authors.initials: B
authors.lastname: Naziruddin
authors.forename: Marlon F
authors.initials: MF
authors.lastname: Levy
authors.forename: Paul A
authors.initials: PA
authors.lastname: Grayburn
authors.forename: Shinichi
authors.initials: S
authors.lastname: Matsumoto
mesh_terms: D000328:Adult; D017364:Collagenases / Q000494:pharmacology*; D005260:Female; D006801:Humans; D007515:Islets of Langerhans / Q000166:cytology*; D016381:Islets of Langerhans Transplantation / Q000379:methods*; D008297:Male; D009926:Organ Preservation / Q000379:methods*; D010183:Pancreatic Ducts
chemical_list: D017364:Collagenases