scholarly journals Chemical Oxygenation of Pancreatic Tissue Prior to Islet Isolation and Transplantation

10.5772/33175 ◽  
2012 ◽  
Author(s):  
Heide Brandhorst ◽  
Paul R. V. Johnson ◽  
Daniel Brandhorst
Keyword(s):  
Pancreatic Tissue ◽  
Islet Isolation

Amount and Distribution of Collagen in Pancreatic Tissue of Different Species in the Perspective of Islet Isolation Procedures

1995 ◽  
Vol 4 (6) ◽  
pp. 609-614 ◽  
Author(s):  
Paul T.R. van Suylichem ◽  
Jan-Erik H.M. van Deijnen ◽  
Gerrit H.J. Wolters ◽  
Reinout van Schilfgaarde
Keyword(s):  
Colorimetric Method ◽  
Pancreatic Tissue ◽  
Collagen Content ◽  
Human Pancreas ◽  
Islet Isolation ◽  
Secondary Importance ◽  
Enzymatic Dissociation ◽  
Tissue Sections ◽  
Dog Pancreas ◽  
General Experience

Because collagen is the major target in the enzymatic dissociation of the pancreas for islet isolation, we determined the amount of collagen and its distribution in a comparative study comprising normal pancreata of rat, dog, man, young pig, and adult pig. Collagen content was determined using a colorimetric method and its distribution was assessed in tissue sections stained with Sirius red. The collagen content is relatively low in the rat and adult pig pancreas, and the amount of collagen is relatively low in the septa of the rat and dog pancreas. Not the amount of collagen in the septa but collagen in the rest of the pancreas, mainly located between the acini, seems to determine the dissociation of the pancreatic tissue. This can be exemplified by the higher islet yields obtained from the adult vs. the young pig pancreas; the latter contains a higher total amount of collagen but a similar, relatively high, amount of collagen in the septa. A high amount of collagen surrounding the islets seems to be of secondary importance in islet isolations, because yields of the same magnitude are obtained from the canine and human pancreas containing a relatively low vs. high amount of collagen around the islets but a similar total collagen content. The rat pancreas contains both a low total amount of collagen and a high amount of collagen around the islets; therefore, the general experience that islet isolation procedures are effective in rats can be readily understood.

scholarly journals Combining Donor Characteristics with Immunohistological Data Improves the Prediction of Islet Isolation Success

2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Zuzana Berkova ◽  
Frantisek Saudek ◽  
Peter Girman ◽  
Klara Zacharovova ◽  
Jan Kriz ◽  
...  
Keyword(s):  
Pancreatic Tissue ◽  
Islet Isolation ◽  
Cold Ischemia Time ◽  
Cold Ischemia ◽  
Immunohistochemical Examination ◽  
Optimal Cutoff ◽  
Factors Associated ◽  
Donor Factors ◽  
Optimal Cutoff Point ◽  
Donor Characteristics

Variability of pancreatic donors may significantly impact the success of islet isolation. The aim of this study was to evaluate donor factors associated with isolation failure and to investigate whether immunohistology could contribute to organ selection. Donor characteristics were evaluated for both successful (n=61) and failed (n=98) islet isolations. Samples of donor pancreatic tissue (n=78) were taken for immunohistochemical examination. Islet isolations with 250000 islet equivalents were considered successful. We confirmed that BMI of less than 25 kg/m2(P<0.001), cold ischemia time more than 8 hours (P<0.01), hospitalization longer than 96 hours (P<0.05), higher catecholamine doses (P<0.05), and edematous pancreases (P<0.01) all unfavorably affected isolation outcome. Subsequent immunohistochemical examination of donor pancreases confirmed significant differences in insulin-positive areas (P<0.001). ROC analyses then established that the insulin-positive area in the pancreas could be used to predict the likely success of islet isolation (P<0.001). At the optimal cutoff point (>1.02%), sensitivity and specificity were 89% and 76%, respectively. To conclude, while the insulin-positive area, determined preislet isolation, as a single variable, is sufficient to predict isolation outcome and helps to improve the success of this procedure, its combination with the established donor scoring system might further improve organ selection.

Amount and distribution of collagen in pancreatic tissue of different species in the perspective of islet isolation procedures

1995 ◽  
Vol 4 (6) ◽  
pp. 609-614 ◽  
Author(s):  
P VANSUYLICHEM ◽  
J VANDEIJNEN ◽  
G WOLTERS ◽  
R VANSCHILFGAARDE
Keyword(s):  
Pancreatic Tissue ◽  
Islet Isolation

scholarly journals Inflammatory biomarkers in the blood and pancreatic tissue of organ donors that predict human islet isolation success and function

Islets ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 9-19
Author(s):  
Alina R. Oancea ◽  
Keiko Omori ◽  
Chris Orr ◽  
Jeffrey Rawson ◽  
Donald C. Dafoe ◽  
...  
Keyword(s):  
Pancreatic Tissue ◽  
Human Islet ◽  
Inflammatory Biomarkers ◽  
Organ Donors ◽  
Islet Isolation ◽  
And Function

Human pancreatic tissue dissociation enzymes for islet isolation: Advances and clinical perspectives

2020 ◽  
Vol 14 (2) ◽  
pp. 159-166
Author(s):  
Gopalakrishnan Loganathan ◽  
Appakalai N. Balamurugan ◽  
Subhashree Venugopal
Keyword(s):  
Pancreatic Tissue ◽  
Islet Isolation ◽  
Tissue Dissociation

scholarly journals Human Pancreatic Islet Isolation: Part I: Digestion and Collection of Pancreatic Tissue

10.3791/1125 ◽  
2009 ◽  
Author(s):  
Meirigeng Qi ◽  
Barbara Barbaro ◽  
Shusen Wang ◽  
Yong Wang ◽  
Mike Hansen ◽  
...  
Keyword(s):  
Pancreatic Islet ◽  
Pancreatic Tissue ◽  
Islet Isolation ◽  
Human Pancreatic Islet ◽  
Pancreatic Islet Isolation

Fractions from Commercial Collagenase Preparations: Use in Enzymic Isolation of the Islets of Langerhans from Porcine Pancreas

1996 ◽  
Vol 5 (5) ◽  
pp. 543-551 ◽  
Author(s):  
Gerd Klöck ◽  
Matthias B. Kowalski ◽  
Bernhard J. Hering ◽  
Martin E. Eiden ◽  
Astrid Weidemann ◽  
...  
Keyword(s):  
Islets Of Langerhans ◽  
Digestive Enzyme ◽  
Scale Up ◽  
Pancreatic Tissue ◽  
Neutral Protease ◽  
Islet Isolation ◽  
Lytic Enzymes ◽  
Porcine Pancreas ◽  
Vitro Assay

Transplantation of isolated islets of Langerhans is an intriguing possibility for the treatment of diabetes mellitus. The isolation of islets from pancreata requires the specific dissociation of the tissue. Commercial collagenases from Clostridium histolyticum are widely used for this purpose. Unfortunately, the effectiveness of these commercial enzymes is not predictable and differs considerably between suppliers and even from lot to lot. This is due mainly to differences in their specific collagenase activity and to the presence of other lytic enzymes, as well as to other contaminants. Free flow zone electrophoresis (FFZE) was used to separate the effective protein components from undesired compounds and to prepare a digestive enzyme mixture with controlled composition of lytic activities. Fractionation of crude collagenases by FFZE resulted in partially purified protein fractions that were enriched for collagenase and tryptic activities, and contained only trace amounts of neutral protease. These preparations proved to be highly effective in an in vitro assay for the liberation of viable islets from porcine pancreas. To scale up the production of these collagenases with defined enzyme composition, we fractionated two different lots of a commercial collagenase from C. histolyticum (one lot effective in islet isolation, the other not) by using fast protein liquid chromatography (FPLC) on hydroxyapatite. Again, high efficacy of islet release from pancreatic tissue was correlated to high specific tryptic and collagenase activities and low levels of neutral protease. The chromatographic protocol developed in this study converted a non-effective collagenase lot into a preparation that allowed successful islet isolation.

Can the density of native pancreatic tissue slices predict human islet isolation and purification outcome?

2004 ◽  
Vol 36 (9) ◽  
pp. 2845-2848 ◽  
Author(s):  
M. Eckhard ◽  
M.D. Brendel ◽  
D. Brandhorst ◽  
H. Brandhorst ◽  
R.G. Bretzel
Keyword(s):  
Pancreatic Tissue ◽  
Human Islet ◽  
Islet Isolation ◽  
Tissue Slices ◽  
Isolation And Purification

scholarly journals Evaluating the Effect of Serine Proteases on Collagenase Activity during Human Islet Isolation

2002 ◽  
Vol 11 (8) ◽  
pp. 821-826 ◽  
Author(s):  
Natisha L. Rose ◽  
Monica M. Palcic ◽  
Jonathan R. T. Lakey
Keyword(s):  
Serine Proteases ◽  
Islet Cells ◽  
Pancreatic Tissue ◽  
Human Islet ◽  
Activity Levels ◽  
Human Pancreas ◽  
Islet Isolation ◽  
Collagenase Activity ◽  
Collagenase Digestion ◽  
Endogenous Enzymes

Inconsistencies in human islet yields after collagenase digestion have been attributed to the activation of endogenous enzymes of the donor pancreas. It has been suggested that pancreatic serine proteases contribute to the proteolysis of collagenase. This study defined the effects of endogenous enzymes within the pancreas on pancreas dissociation during collagenase digestion. Levels of collagenase activity from samples taken throughout several steps in islet isolation procedures, both with and without the addition of the serine protease inhibitor Pefabloc, were determined by a spectrophotometric assay using N-[3-(2-furyl)acryloyl]-Leu-Gly-Pro-Ala as the substrate. Results clearly demonstrated that the level of collagenase activity remains stable throughout the isolation procedure despite differences in the donor factors from several cadaveric donor pancreases. This was further demonstrated by observing no difference in activity levels after incubating commercial collagenase preparations with serine proteases and analyzing by means of collagenase activity and SDS-PAGE. These data show that the presence of serine proteases does not affect the level of collagenase activity; however, they likely damage the islet cells upon prolonged digestion of the pancreatic tissue. Further efforts at examining exogenous and endogenous enzyme levels may result in the development of an enzyme cocktail that is both stable and effective for digesting the human pancreas while preserving islet function and viability.

scholarly journals 1H MAS NMR of Donor Pancreatic Tissue is a Useful Predictor of Islet Viability Prior to Islet Isolation

2020 ◽  
Author(s):  
Lisa M.H. Tanguay ◽  
Carolyn M. Slupsky ◽  
Toshiaki Toshiaki ◽  
Bruce Lix ◽  
Brian D. Sykes ◽  
...  
Keyword(s):  
Nmr Spectra ◽  
Pancreatic Tissue ◽  
Mas Nmr ◽  
Human Pancreas ◽  
Islet Isolation ◽  
Tissue Samples ◽  
1H Mas Nmr ◽  
University Of Wisconsin ◽  
Clinical Islet Transplantation ◽  
Glucose Responsiveness

AbstractA significant limitation and cost to any clinical islet program is the related to processing human pancreas and not recovering significant numbers of viable islets for clinical transplantation. The development of an assay system that could be utilized and provide an index of cell and tissue viability before islet isolation would provide a major impact on the scientific aspects of organ preservation and a huge cost saving to any clinical islet transplantation program.Metabolomic analysis by 1H MAS NMR was used to assess samples of donor pancreatic tissue taken prior to islet isolation. A significant correlation was observed between the ratio of the combined integrals of the sugar (3.5-4.5 ppm) and choline (3.0-3.5 ppm) regions to the integrals of the CH3 (0.9 ppm) and CH2 (1.3 ppm) peaks of the 1H MAS NMR spectra of pancreatic tissue samples taken prior to islet isolation and the glucose responsiveness, a measure of islet viability, of the isolated islets (P<0.05). The effect of the two-layer (University of Wisconsin solution/perfluorochemical [UW/PFC]) cold-storage method, previously shown to restore ischemically damaged pancreases by increasing oxygenation, was also studied using 1H MAS NMR spectroscopy. PFC recovery of the donor pancreas also correlated with an increase in the combined integrals of the sugar and choline regions to the CH3 and CH2 peaks of the 1H MAS NMR spectra (P<0.05). In addition, significant differences in the integrals of the sugar region and CH2 peaks were observed between the pre- and post-PFC samples (P<0.05). These results support the notion that specific metabolites observed in 1H MAS NMR can be used as a means to assess reversible/irreversible tissue damage and offers a means to assess donor pancreatic tissue prior to islet isolation for transplantation.

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