title: Impact of the two-layer method on the quality of isolated pancreatic islets.
abstract: OBJECTIVE
  We have already reported that the two-layer method (UW/PFC) reduces warm and cold ischemic injuries before islet isolation, and results in improvement of islet yield and viability. In this study, we try to evaluate the effect of the two-layer method on isolated islets.
  
  
  METHODS
  We used male Wister rats. Isolated islets were cultured or preserved in various conditions for 24 hours. In group 1, islets were not cultured (control). In group 2, islets were cultured in RPMI at 37 degrees C. In groups 3 and 4, islets were cultured with "modified" two-layer method (RPMI/PFC) at 37 degrees C and 4 degrees C, respectively. In groups 5 and 6, islets were preserved in UW and with the two-layer method (UW/PFC), respectively at 4 degrees C. Islets in each group were evaluated in terms of function and viability in vitro.
  
  
  RESULTS
  Stimulation Indices were 1.3, 2.6, 3.7, 1.2, 1.4, and 2.4 in groups 1, 2, 3, 4, 5 and 6, respectively. Islets in groups 2, 3 and 6 showed clear response to glucose stimulation. Among these 3 groups, the total viability of islets assessed by FDA/PI staining was 88%, 92%, and 76% in groups 2, 3, 6, respectively.
  
  
  CONCLUSIONS
  Although in vivo studies are mandatory, the present study is supportive that the "modified" two-layer method (RPMI/PFC), which uses oxygenated PFC and RPMI, may be superior to conventional culture method with RPMI. This method may achieve further improvement of islet viability before implantation.
authors.affiliation: Division of Gastroenterological Surgery, Kobe University Graduate School of Medicine Kobe, Japan.
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Takahashi
authors.forename: Yasuki
authors.initials: Y
authors.lastname: Tanioka
authors.forename: Takeru
authors.initials: T
authors.lastname: Matsuda
authors.forename: Hirochika
authors.initials: H
authors.lastname: Toyama
authors.forename: Keitaro
authors.initials: K
authors.lastname: Kakinoki
authors.forename: Seijitu
authors.initials: S
authors.lastname: Li
authors.forename: Kunihiko
authors.initials: K
authors.lastname: Hiraoka
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Fijino
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Suzuki
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Kuroda
mesh_terms: D000241:Adenosine; D000493:Allopurinol; D000818:Animals; D003080:Cold Temperature; D011464:Epoprostenol; D005466:Fluorocarbons; D005973:Glutamine; D005978:Glutathione; D006895:Hydroxyethyl Starch Derivatives; D007328:Insulin / Q000378:metabolism; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000502:physiology* / Q000601:surgery; D008278:Magnesium Sulfate; D008297:Male; D009536:Niacinamide; D019188:Organ Preservation Solutions; D011887:Raffinose; D051381:Rats; D017208:Rats, Wistar; D014021:Tissue Preservation / Q000379:methods*; D014022:Tissue Survival; D020858:Tissue and Organ Harvesting; D014199:Trehalose
chemical_list: D005466:Fluorocarbons; D006895:Hydroxyethyl Starch Derivatives; D007328:Insulin; D019188:Organ Preservation Solutions; C431558:PFC-Kyoto solution; C055206:University of Wisconsin-lactobionate solution; D005973:Glutamine; D009536:Niacinamide; D000493:Allopurinol; D008278:Magnesium Sulfate; D014199:Trehalose; D011464:Epoprostenol; D005978:Glutathione; D000241:Adenosine; D011887:Raffinose