In vitro effect of bioscaffolds on viability and insulin‑producing function of human islets of Langerhans

Abstract

The culture of islets of Langerhans with bioscaffolds – extracellular matrix (ECM) mimetics – can provide a native microenvironment suitable for islets. This is one of the main conditions for creating a pancreatic tissue equivalent.Objective: to compare the secretory capacity of viable human pancreatic islets in monoculture (control group) and cultured in the presence of two bioscaffolds: biopolymer collagen-based hydrogel scaffold (experimental group 1) and tissue-specific scaffold from decellularized deceased donor pancreas (experimental group 2).Materials and methods. Islets of Langerhans were isolated from the caudal pancreas using a collagenase technique. The viability of cultured islets was accessed by vital fluorescence staining, while secretory capacity was evaluated by enzyme-linked immunosorbent assay (ELISA).Results. Pancreatic islets cultured with bioscaffolds showed no signs of degradation and fragmentation, they remained viable throughout the entire period of observation (7 days). The monoculture of islets showed significant destructive changes during this period. Basal insulin levels in experimental groups 1 and 2 increased by 18.8% and 39.5% on day 1 of culture compared to the control group, by 72.8% and 102.7% on day 4 of incubation, and by 146.4% and 174.6% on day 7, respectively. The insulin secretion level of islets with tissue-specific scaffolds was 17.4% higher than that when cultured with biopolymer collagen-based scaffolds.Conclusion. Biopolymer and tissue-specific ECM mimetics contribute not only to preservation of the viability of isolated islets of Langerhans but also maintain their insulin secretion capacity for 7 days at a higher level in comparison with monoculture. The experiments revealed that the use of a tissue-specific scaffold for the creation of a pancreatic tissue equivalent has slight potential advantage over biopolymer scaffold.