Superiority of visipaque (iodixanol)-controlled density gradient over Ficoll-400 in adult porcine islet purification.
OBJECTIVE
Sufficient and favorable biological functions of islets are major problems hindering xenotransplantation. The aim of the present study was to evaluate the effects on harvesting, purity, viability, and function of using improved Visipaque (iodixanol) and Ficoll-400 for adult porcine islet purification.


METHODS
Twelve adult porcine pancreata were randomly divided into an Iodixanol-University of Wisconsin (UW) group and a Ficoll-400-UW group according to the purification method. Porcine pancreata were isolated by collagenase digestion. After isolation and purification, the islet yield and purity were evaluated by dithizone staining, and islet function assessed by in vitro insulin release assays and in vivo islet xenotransplantation.


RESULTS
There were no marked differences in the islet yield before purification (5254.67 +/- 189.44 IEQ/g vs 5092.67 +/- 178.94 IEQ/g, P > .05). After purification, there were significantly more islets harvested in Iodixanol-UW group than in the Ficoll-400-UW group: 4222.00 +/- 228.84 IEQ/g vs 3036.83 +/- 79.60 IEQ/g (P < .05). Islets from the two groups showed satisfactory insulin secretory ability. There were no significant differences in islet survival times between the two groups in diabetic rats: 8.2 +/- 1.619 days vs 6.9 +/- 1.197 days (P > .05).


CONCLUSIONS
The improved iodixanol-UW density gradient method was superior to Ficoll-400 method to improve the number, viability, and insulin secret of purified adult porcine islets although the benefits did not improve in vivo survival.
Min
T
T
Department of Hepatobiliary Surgery, First Affiliated Hospital, Medical College, Xi'an Jiaotong University, Xi'an, People's Republic of China.
Yi
L
L
Chao
Z
Z
Haitao
Z
Z
Wei
W
W
Liang
Y
Y
Bo
W
W
D000241:Adenosine; D000493:Allopurinol; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D002452:Cell Count / Q000379:methods; D002469:Cell Separation / Q000379:methods*; D002470:Cell Survival; D003287:Contrast Media; D003921:Diabetes Mellitus, Experimental / Q000601:surgery*; D005362:Ficoll; D005978:Glutathione; D007328:Insulin / Q000378:metabolism; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000166:cytology*; D016381:Islets of Langerhans Transplantation / Q000379:methods*; D019188:Organ Preservation Solutions; D011887:Raffinose; D051381:Rats; D017207:Rats, Sprague-Dawley; D013552:Swine; D014183:Transplantation, Heterologous; D014283:Triiodobenzoic Acids
D001786:Blood Glucose; D003287:Contrast Media; D007328:Insulin; D019188:Organ Preservation Solutions; D014283:Triiodobenzoic Acids; C055206:University of Wisconsin-lactobionate solution; D005362:Ficoll; D000493:Allopurinol; D005978:Glutathione; C044834:iodixanol; D000241:Adenosine; D011887:Raffinose