AUTHOR=Buemi Antoine , Mouard Nizar I. , Darius Tom , Devresse Arnaud , Kanaan Nada , Gianello Pierre , Mourad Michel 

TITLE=Continuous vs. discontinuous purification of isolated human islets: functional and morphological comparison

JOURNAL=Frontiers in Endocrinology

VOLUME=14

YEAR=2023

URL=https://www.frontiersin.org/journals/endocrinology/articles/10.3389/fendo.2023.1195545

DOI=10.3389/fendo.2023.1195545

ISSN=1664-2392

ABSTRACT=<sec><title>Background</title><p>The COBE 2991 cell processor, commonly used for pancreatic islet isolation, is no longer distributed in Europe, leading to a search for alternative purification procedures with equivalent efficacy. The aim of this study was to evaluate the efficacy of an alternative method based on the discontinuous purification of islets.</p></sec><sec><title>Methods</title><p>The conventional isolation procedure using a standard continuous islet purification with COBE 2991 of <italic>n</italic> = 4 human pancreas was compared to <italic>n</italic> = 8 procedures using a discontinuous purification with a “bottle” method from donors of similar characteristics. Islet equivalents, purity, and dynamic glucose-stimulated insulin secretion were evaluated.</p></sec><sec><title>Results</title><p>A similar islet yield was obtained using continuous vs. discontinuous purification methods (76,292.5 ± 40,550.44 vs. 79,625 ± 41,484.46 islet equivalents, <italic>p</italic> = 0.89). Islets from both groups had similar purity (78.75% ± 19.73% vs. 55% ± 18.16%, <italic>p</italic> = 0.08) and functionality both in terms of stimulation index (3.31 ± 0.83 vs. 5.58 ± 3.38, <italic>p</italic> = 0.22) and insulin secretion (1.26 ± 0.83 vs. 1.53 ± 1.40 mean AUC, <italic>p</italic> = 0.73). Moreover, the size of the islets was significantly larger in the discontinuous vs. continuous purification group (19.2% ± 10.3% vs. 45.4% ± 18.8% of islets less than 100 µm, <italic>p</italic> = 0.0097 and 23.7% ± 5.3% vs. 15.6% ± 5.8% of 200–250 µm islet size, <italic>p</italic> = 0.03).</p></sec><sec><title>Conclusion</title><p>Compared to the conventional purification procedure, discontinuous purification with a bottle method shows similar results with regard to isolation yield and islet secretory function. Furthermore, this alternative technique allows for obtaining larger islets.</p></sec>