TY - JOUR
T1 - Effect of Human Islet Rescue Gradient Purification on Islet Yield and Fractional Beta Cell Viability
AU - Miki, A.
AU - Ricordi, C.
AU - Yamamoto, T.
AU - Mita, A.
AU - Barker, S.
AU - Khan, A.
AU - Alejandro, R.
AU - Ichii, H.
N1 - Funding Information:
Supported by: NIH, NIDDK, ICR, JDRF, and DRIF.
Copyright:
Copyright 2008 Elsevier B.V., All rights reserved.
PY - 2008/3
Y1 - 2008/3
N2 - It is difficult to consistently obtain sufficient postpurification islet numbers from younger donors because of the higher proportion of trapped islets after pancreas digestion. Continuous gradient purification (CGP), which is currently used in several islet processing centers, sometimes is not efficient in the purification of trapped islets. Rescue gradient purification (RGP) could improve postpurification islet yields, resulting in an increased number of islet cell products that could be transplanted. Sixty-eight human islet isolations, in which CGP was followed by RGP were analyzed. The quality of islets from CGP and RGP was assessed by β-cell fractional viability (βFV) and ADP/ATP ratio. Donor age negatively correlated with the proportion of the islets rescued by RGP (R = -0.52; P < .01) and to the percentage of trapped islets (R = -0.46; P < .01). Age-related differences were observed in pancreas weight, digestion time, and islet yields from CGP, respectively. Importantly, islets from RGP had an 11% higher βFV compared with islets from CGP. ADP/ATP ratio was also lower in RGP islets versus CGP islets. RGP improved the efficiency of islet purification from younger pancreata and did not affect islet cell viability, which was actually higher in RGP fractions, indicating that rescued trapped islets from the pellet and lower purity layers are not damaged by the extra purification step and may actually be more viable. RGP could be used to rescue high-quality islets from less than 30% pure islet fractions, which are often discarded in the clinical setting.
AB - It is difficult to consistently obtain sufficient postpurification islet numbers from younger donors because of the higher proportion of trapped islets after pancreas digestion. Continuous gradient purification (CGP), which is currently used in several islet processing centers, sometimes is not efficient in the purification of trapped islets. Rescue gradient purification (RGP) could improve postpurification islet yields, resulting in an increased number of islet cell products that could be transplanted. Sixty-eight human islet isolations, in which CGP was followed by RGP were analyzed. The quality of islets from CGP and RGP was assessed by β-cell fractional viability (βFV) and ADP/ATP ratio. Donor age negatively correlated with the proportion of the islets rescued by RGP (R = -0.52; P < .01) and to the percentage of trapped islets (R = -0.46; P < .01). Age-related differences were observed in pancreas weight, digestion time, and islet yields from CGP, respectively. Importantly, islets from RGP had an 11% higher βFV compared with islets from CGP. ADP/ATP ratio was also lower in RGP islets versus CGP islets. RGP improved the efficiency of islet purification from younger pancreata and did not affect islet cell viability, which was actually higher in RGP fractions, indicating that rescued trapped islets from the pellet and lower purity layers are not damaged by the extra purification step and may actually be more viable. RGP could be used to rescue high-quality islets from less than 30% pure islet fractions, which are often discarded in the clinical setting.
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U2 - 10.1016/j.transproceed.2008.02.008
DO - 10.1016/j.transproceed.2008.02.008
M3 - Article
C2 - 18374067
AN - SCOPUS:40949098663
VL - 40
SP - 360
EP - 361
JO - Transplantation Proceedings
JF - Transplantation Proceedings
SN - 0041-1345
IS - 2
ER -