Improve islet yields and quality when clinical grade pancreata are preserved by the two-layer method.
BACKGROUND
Research grade pancreata preserved by the two-layer method (TLM) yield significantly greater numbers of islets than organs stored with University of Wisconsin solution (UW). The goal of this study was to determine whether this would hold true for pancreata that meet selection criteria for clinical grade organs.


METHODS
Pancreata were chosen based upon a pre-defined set of criteria used for selecting clinical grade pancreata. Thirteen of these organs were preserved in UW and five pancreata were preserved by the TLM. Islets were isolated and evaluated according to the Edmonton protocol.


RESULTS
The average preservation time was significantly longer for organ preserved with TLM (9.5 + 2.0 h) as compared to UW (5.8 + 0.6 h, p = 0.015). The pancreata of TLM group resulted in a significant increase in islet yields (3588 +/- 500 vs. 2536 +/- 312 IE/g pancreas, p<0.05). Visual scoring of islets indicated that islets were better from TLM group (8.3 +/- 0.3 vs. 7.3 +/- 0.2), and islet survival rates after culture were higher from organs stored with the TLM (87 +/- 17 vs. 55 +/- 7.4, p<0.05). Other parameters such as viability, insulin content, and stimulation index were similar between the two groups. All the preparations from the TLM group, but only 54% of preparations from the UW group, qualified for islet transplantation. The two recipients receiving islets from TLM group, daily insulin requirements were reduced and C-peptide levels were increased.


CONCLUSIONS
Compared to storage with UW, exposure of pancreata to the TLM resulted in greater islet yields and improved quality of islets despite longer preservation period. Consequently, pancreata that meet clinical grade status should be preserved by the TLM prior to islet isolation.
Zhang
Guangming
G
Northwest Tissue Center at the Puget Sound Blood Center, Seattle, WA 98104, USA.
Matsumoto
Shinichi
S
Newman
Helen
H
Strong
D Michael
DM
Robertson
R Paul
RP
Reems
Jo-Anna
JA
D000241:Adenosine; D000328:Adult; D000493:Allopurinol; D005978:Glutathione; D006801:Humans; D007328:Insulin; D007515:Islets of Langerhans; D008875:Middle Aged; D009926:Organ Preservation; D019188:Organ Preservation Solutions; D011887:Raffinose
D007328:Insulin; D019188:Organ Preservation Solutions; C055206:University of Wisconsin-lactobionate solution; D000493:Allopurinol; D005978:Glutathione; D000241:Adenosine; D011887:Raffinose